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Quercetin (QCT) is a flavonoid with significant health benefits, necessitating sensitive detection methods for food safety and quality control. This study presents a novel UiO-66-TCPP ratiometric fluorescent probe for the quantitative and visual detection of QCT. Under optimal conditions, the fluorescence intensity of UiO-66-TCPP decreased linearly with increasing QCT concentration, with a detection limit of 26 nM. The probe demonstrated high specificity, showing no significant interference from various substances and QCT analogues. Practical applicability was confirmed by testing artificially contaminated juice samples, achieving recovery rates between 98.0% and 104.8%. Furthermore, a paper-based sensor was developed by incorporating UiO-66-TCPP onto Whatman#1 chromatography paper. This sensor exhibited stable fluorescence and a reliable, sensitive visual response to QCT concentrations, detectable via a smartphone-based color recognizer application. The UiO-66-TCPP ratiometric fluorescent probe provides a sensitive, specific, and practical method for detecting QCT in food matrices, offering significant potential for both laboratory and on-site applications. • A ratiometric fluorescent probe, namely UiO-66-TCPP, was synthesized for the detection of quercetin. • A paper-based sensor utilizing UiO-66-TCPP was fabricated for convenient on-site detection. • The ratiometric fluorescent probe exhibited remarkable sensitivity, with a detection limit as low as 26 nM. [ABSTRACT FROM AUTHOR]

[Display omitted] • A high SERS efficiency Au nanodendrite (AuND) structure was constructed by electro-deposition on a 3D nickel foam (NiF). • NiF with a highly porous structure and concave microchannel was employed as a sampling-diffusing medium. • AuND/NiF was situated onto a paper strip to construct a paper-based chromatography device (PP-AuND/NiF). • AuND/NiF substrate could detect R6G at 0.1 nM. • The PP-AuND/NiF could simultaneously separate and detect R6G in a mixture solution containing R6G and 2-NpSH. A simple paper-based chromatography coupling with nickel foam decorated Au nanodendrite (PP-AuND/NiF) was fabricated for simultaneous separation and surface-enhanced Raman scattering (SERS) detection of Rhodamine-6G (R6G) from a mixture of analytes. The three-dimensional porous nickel foam (NiF) was employed as a sampling diffusion platform, and AuND with a high surface active area beneficial for SERS efficiency was electro-deposited directly onto the NiF frame. The structure of AuND/NiF was characterized by X-ray diffraction and scanning electron microscopy. The AuND/NiF could detect R6G at 0.1 nM, and the enhancement factor was 1.84 x 106. The AuND/NiF was durable, with a slight signal decrease after 6 m of drop-testing. Also, upon three days of exposure to ambient air, the signal droped only 3.35 %. Subsequently, the PP-AuND/NiF was constructed by directly situating AuND/NiF on a paper strip, serving as a sample in and out to AuND/NiF. A mixture of two SERS active compounds, namely 2-Naphthalenethiol (2-NpSH) and Rhodamine 6G (R6G), was prepared in ethanol: water (1:1) solution to evaluate PP-AuND/NiF separation capability. Raman measurements along different distances of AuND/NiF were performed, and the signal of 2-NpSH was dismissed after 3.0 mm, while R6G's signals were observed throughout AuND/NiF. In general, the PP-AuND/NiF demonstrated effective separation and SERS measurement of analytes in a mixture, which could be applicable for more complex samples in the future, especially in clinical analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chromatography paper was used to develop an analytical device to detect salt. • Chloride ions reacted with silver nanoparticles and carboxymethyl cellulose. • Stability and interference against Cl− detection were good. • The device detected salt in twenty-five food samples. Using silver nanoparticles (AgNPs) and carboxymethyl cellulose (CMC), a simple distance-based paper analytical device (dPAD) was developed for the determination of chloride ions in food products. The determination of chloride ions was based on the Mohr argentometric method without the chromium compound. A hydrophobic barrier was created on chromatography paper using a wax-printing technique. The barrier protected a channel that was impregnated with AgNPs and CMC. In the presence of chloride, chloride ions moved along the channel, reacting with AgNPs, and forming an AgNPs-Cl sediment deposited as a white/gray precipitation in the orange-colored channel. The chloride ion concentration was interpreted from the length of the color change visualized with the naked eye without external equipment. The amount and volume of AgNPs and CMC impregnated on the chromatography paper were optimized. The response of the AgNPs-CMC/dPAD to the chloride ion was linear from 0.01 to 1.00 % w/v (r = 0.9931). In addition, the proposed device was stable for more than 28 days, with a relative response of 105 ± 3 % compared to day one, resulting in consistent and precise results. Intra-day (6 measurements) and inter-day (over 6 days) precision were excellent with RSDs less than 6 %. The developed dPAD was used to detect salt in twenty-five real samples, including instant noodles, condiments and sauces, and snacks. Recoveries ranged from 96 ± 5 to 105 ± 5 %. The proposed method showed acceptable accuracy, precision and good shelf life for monitoring chloride in food products at the point of need and demonstrated potential for commercial development. [ABSTRACT FROM AUTHOR]

[177Lu]Lu-DOTA-Ahx-Lys40-Exendin-4 ([177Lu]Lu-DOTA-Exendin-4) is a potential agent for radiotherapy of insulinomas owing to its specificity towards GLP-1 (Glucagon like peptide-1) receptors over-expressed on such cancers. The objective of the present study is to optimize the various radiochemistry parameters for the consistent formulation of the agent with high radiolabeling yield using carrier added [177Lu]LuCl 3 and also to evaluate its biological behaviour in small animal model. In order to optimize the radiolabeling parameters, DOTA-Exendin-4 was radiolabeled with [177Lu]LuCl 3 in two different buffer systems (sodium acetate and HEPES) at three different temperatures (45, 65 and 95 °C) using three different ligand to metal ratios (3:1, 4:1 and 5:1). The radiolabeled peptide was characterized by both paper chromatography and HPLC. The effect of addition of three different radio-protectors on complexation yield was also studied. Bio-distribution studies were carried out in healthy Swiss mice to evaluate the pharmacokinetic behaviour of the radiolabeled peptide as well as to determine the in vivo specificity of the radiotracer towards GLP-1 receptors (blocking studies). Urine and kidney lysate of the animals were analyzed at various post-administration time-points in order to determine the in vivo stability of the radiolabeled peptide. The [177Lu]Lu-DOTA-Exendin-4 complex could be prepared consistently with >95% radiolabeling yield using the optimized reaction conditions. Bio-distribution studies revealed early accumulation of [177Lu]Lu-DOTA-Exendin-4 in pancreas along with fast clearance via renal pathway. Significantly high accumulation of the radiotracer was observed in kidneys. Analyses of urine and kidney lysate of the animals revealed in vivo stability of [177Lu]Lu-DOTA-Exendin-4. Blocking studies showed displacement of significant amount of radiotracer from GLP-1 receptor-positive organs such as, pancreas and lungs (p <0.05) in presence of unlabeled peptide, indicating the specificity of the radiolabeled preparation towards GLP-1 receptors. Present study shows that [177Lu]Lu-DOTA-Exendin-4 could be formulated for radiotherapeutic application with high radiochemical purity and adequate in vivo stability using [177Lu]LuCl 3 produced via direct neutron irradiation. Findings of the present study will be helpful in preparing the patient dose of [177Lu]Lu-labeled Exendin for radiotherapy of insulinoma using carrier added [177Lu]LuCl 3 , produced in a medium flux reactor, without the requirement of post-labeling purification. [ABSTRACT FROM AUTHOR]

The adulteration of herbal medicines by dexamethasone or prednisolone is regarded as a serious problem in many communities. Herein, a novel platform for the separation and quantification of both target steroids in herbal medicines based on electrochemical paper-based analytical devices (ePADs) has been created. The ePAD was composed of Whatman SG81 chromatography paper, 3D-printed devices and a commercial screen-printed electrode. Whatman SG81 silica-coated paper was used for the separation of dexamethasone and prednisolone based on the difference in their partition coefficients during the flow of the mobile phase. The optimal mobile phase was composed of 60% ethyl acetate in cyclohexane and required 7 min for separation. The separated steroids on the paper were then quantified by electrochemical detection using differential pulse voltammetry, in which the 3D-printed devices facilitated the measurement. Analytical detection ranges of 10–500 μg mL−1 were obtained for both dexamethasone and prednisolone (r2 = 0.988 and 0.994, respectively). The limits of detection for dexamethasone and prednisolone were 3.59 and 11.98 μg mL−1, respectively, whereas the limits of quantification were 6.00 and 20.02 μg mL−1, respectively. The amounts of both target steroids derived from real herbal medicine samples determined by the proposed method were comparable to those obtained with assays using standard high-performance liquid chromatography. In addition, a simple evaporation step can be used to increase the concentration of the samples before analysis. These ePADs are simple, low-cost, rapid, and very promising for on-site quantitative detection. Image 1 • An ePAD is introduced for the first time quantification of adulterated dexamethasone and prednisolone in herbal medicines. • Prednisolone and dexamethasone were separated by means of differences in partition and detected by electrochemistry. • An in-house-3D-printed cassette facilitated and stabilised electrochemical signals on the ePAD. [ABSTRACT FROM AUTHOR]

A novel microfluidic paper-based analytical device (μPAD) was developed with benzoquinone (BQ)-mediated E. coli respiration method to measure the biotoxicities of pollutants. Functional units including sample injection, fluid-cell separation, all-carbon electrode-enabled electrochemical detection, were integrated on a piece of chromatography paper. The three-electrode, working electrode, counter electrode and reference electrode, were simultaneously screen-printed on the μPAD with conductive carbon ink. The satisfying electrochemical performance of the paper-based carbon three-electrode was confirmed by cyclic voltammetry detecting K 3 [Fe(CN) 6 ]. The process of cell toxication was considered that toxicants inhibited cell respiration and diminished the electrons on E. coli respiratory chain. It was quantitatively reflected by measuring oxidation current of hydroquinone (HQ) as a reduced state of the redox mediator BQ after the incubation of cells with pollutants. The current detection time, BQ concentration and E. coli incubation time were carefully optimized to establish the systematic optimized operations of BQ-mediated E. coli respiration method. Using the fabricated μPAD the half inhibitory concentration (IC 50) were Cu2+ solution 13.5 μg mL−1, Cu2+-soil 21.4 mg kg−1, penicillin sodium-soil 85.1 mg kg−1, and IC 30 of Pb2+ solution was 60.0 μg mL−1. Detection of pesticide residues in vegetable juices were accomplished in a similar way. The proposed method is fascinating on three points; 1) The generality in the biotoxicity detection depends on toxicants inducing cellular respiratory inhibition; 2) The portability and affordability make it convenient for practical applications, because of replacing incubators and centrifuges; 3) There is potential applicability in less-developed areas due to its simple operation and low-cost. Image 1 • Biotoxicities of multiple environmental pollutants were quantitatively measured and compared by using a μPAD. • Living microorganism E. coli was used as a direct biotoxicity indicator through its respiratory inhibition induced by toxicants. • Detection samples in the form of solution, soil and vegetable juice were all applicable to this μPAD. • The μPAD was fully screen-printed, including carbon three-electrode and all functional units. [ABSTRACT FROM AUTHOR]

[Display omitted] • New Schiff base sensor R4P developed using Rhodamine B fluorophore. • Highly sensitive and selective towards Al3+/Cu2+ in two solvent systems. • Low LOD, high K A , good anti-interference and reversibility properties. • Fabrication of strip for on-site detection using chromatography paper. • Low cytotoxicity of R4P makes it suitable for bio-imaging studies. In order to create a new Schiff base sensor R4P , rhodamine B hydrazide was directly combined with 4-propoxybenzaldehyde. The structure of this new sensor was completely revealed by spectroscopic methods, and a single crystal that could be used for X-ray diffraction techniques was produced. Under a UV lamp, the colourless and non-fluorescent R4P solution exhibits an orange fluorescence enhancement when Al3+ is present and showed a pink colour change when Cu2+ is present. Spectroscopic tools like UV, fluorescence, MS and NMR spectroscopy were used to study the recognition performance and complexation process of the sensor. The findings demonstrated that sensor R4P , with a limit of detection as low as 10-8 M and an association constant of ×104 M−1, is highly sensitive and selective towards both Al3+ and Cu2+ in two different solvent systems. Additionally, the designed system had a reasonable recovery range of above 89% for Al3+ and Cu2+ in two chosen water samples of natural mineral water and tap water. Moreover, a paper-based test strip that can detect target metal ions both colorimetrically and fluorometrically was created utilising chromatography paper. Aside from that, R4P 's minimal cytotoxicity marks it appropriate for bio-imaging studies on metal ion sensing using the fluorescence response in the HCT 116 cell line. [ABSTRACT FROM AUTHOR]

Paper spray ionization is a simple method to analyze samples by mass spectrometry (MS) without sample preparation. However, using paper substrates results in limited performance due to low lifetime, low reproducibility, severe analyte diffusion, and poor chromatography. To address these issues, a stereolithography 3D printed microfluidic paper-based column coupled to liquid chromatography-MS (µPC-LC-MS) was developed. The fabrication process created well-defined microchannels inside a single paper substrate in less than 1 s. The µPC-LC-MS significantly extended the lifetime of the substrate, up to 50 min per run with continuous gradient elution at a flow rate of 20 µL min-1 from regular LC pumps. A single µPC can be reused up to 5 cycles with an RSD of 9.5 % without signal reduction, overloading, or interference. Separation of three psychoactive substances/metabolites (methamphetamine, 7-aminonitrazepam, and morphine-3-glucuronide) was achieved with peak resolution from 0.50 to 1.21, high sensitivity (LOD between 0.5 and 1 ng mL-1) and accuracy (87.0–109.1 %), linearity from 5 to 500 ng mL-1 in both water and plasma, and coefficient of determination (R 2 ) from 0.993 to 1.000 using only 1 µL plasma. The µPC-LC-MS demonstrated robustness and sensitivity, making it a promising tool for bioanalysis based on paper-based microfluidics. [Display omitted] • Stereolithography 3D printed microfluidic paper-based columns extend PSI lifetime up to 50 min. • LC gradient was used for the first time in paper column chromatography. • A µPC showed 5-cycle reusability with 9.5 % RSD, no signal reduction, and no interference. • Plasma separation of 3 substances achieved with 0.50–1.21 peak resolution. • The method achieved a detection limit of 0.5–1 ng mL-1 using only 1 µL of plasma. [ABSTRACT FROM AUTHOR]

• A cellulose membrane serves as stationary phase for fractionation of human saliva. • Interaction between red wine and saliva was revealed by a dichromatic analysis. • A non-diffusible salivary fraction showed the highest affinity for wine components. • Diffusion of a diffusible salivary fraction declines due to interaction with wine. • A point of equivalence occurs when a wine/saliva mix shows no diffusible fraction. In-mouth interaction of red wine compounds with salivary proteins is a primary event allegedly responsible for eliciting the mouth-feel sensation of astringency. Those interactions have been currently associated with precipitation of salivary protein/polyphenol complexes. However, such single physicochemical evidence for interaction does not account for the complexity of astringency. This study aimed to develop a paper chromatography method to assess interactions between red wine and the salivary protein fraction using stepwise series of red wine/saliva binary mixtures from 100% wine to 100% saliva ("Alpha and Omega series"). Aliquots of each one of the mixtures were spotted on a cellulose membrane to scrutinize independently the distribution areas of wine components (naturally pink-colored) and salivary protein (stained blue in Coomassie Brilliant R-250). This double target detection revealed interactions between saliva and red wine components along most of the quantitative Alpha and Omega series, a point of equivalence corresponding to maximum interactivity for both complex reactants and a non-diffusible sub-fraction of saliva displaying the highest interactivity. The results indicate a novel way to assess quantitatively physicochemical interactions between red wines and human saliva but also provide new lights to approach the identification of molecular salivary structures involved in triggering astringency. [ABSTRACT FROM AUTHOR]

Microfluidic paper-based analytical devices (mPADs) have gained significant attention in recent years for applications ranging from clinical diagnostics to environmental testing. However, separation on mPADs remains challenging to implement, particularly in complex samples. This has revived interest in revisiting paper chromatography and paper electrophoresis in mPADs to address these needs. Here, laminated Parafilm-paper (l-paper) is applied to fabricate electrophoretic devices. This approach yields a free-standing channel, leading to improved peak resolution relative to previous electrophoretic separations in traditional wax-printed mPADs. Major factors influencing the separation, including Joule heating, electroosmotic flow, and electrophoretic mobility, were investigated. As a result of paper’s high ratio of surface area (78%) to pore volume (22%) resulting in slow heat dissipation, a usable applied field strength range of 0–200 V cm −1 was employed to avoid Joule heating. The electroosmotic flow of the system was found to be 2.5 × 10 −5 ± 7.7 × 10 −7  cm 2 V −1  s −1 and the electrophoretic mobility of chlorophenol red was 1.2 × 10 −4 ± 7.7 × 10 −7  cm 2 V −1  s −1 . Basic separation protocols were optimized using colorimetric detection of chlorophenol red and indigo carmine dyes as representative molecules. Paper type, channel width, and applied potential were then used to optimize the separations. Addition of an injection port to the device improved resolution and reduced peak broadening. Finally, the separation of fluorescein isothiocyanate (FITC) and l -glutamic acid (Glu) labeled with FITC, was successfully carried out using the l-paper electrophoretic device. Imaging with a microscope was found to achieve reduced peak broadening and increased resolution relative to imaging with a mobile camera, due to elimination of background signal, achieving a 72 ± 4% conjugation of Glu and FITC. [ABSTRACT FROM AUTHOR]

Background: Fermentation is a widely used method of natural food preservation that has consequences on the nutritional value of the transformed food. Fermented dairy products are increasingly investigated in view of their ability to exert health benefits beyond their nutritional qualities.Objective: To explore the mechanisms underpinning the health benefits of fermented dairy intake, the present study followed the effects of milk fermentation, from changes in the product metabolome to consequences on the human serum metabolome after its ingestion.Methods: A randomized crossover study design was conducted in 14 healthy men [mean age: 24.6 y; mean body mass index (in kg/m2): 21.8]. At the beginning of each test phase, serum samples were taken 6 h postprandially after the ingestion of 800 g of a nonfermented milk or a probiotic yogurt. During the 2-wk test phases, subjects consumed 400 g of the assigned test product daily (200 g, 2 times/d). Serum samples were taken from fasting participants at the end of each test phase. The serum metabolome was assessed through the use of LC-MS-based untargeted metabolomics.Results: Postprandial serum metabolomes after milk or yogurt intake could be differentiated [orthogonal projections to latent structures discriminant analysis (OPLS-DA) Q2 = 0.74]. Yogurt intake was characterized by higher concentrations of 7 free amino acids (including proline, P = 0.03), reduced concentrations of 5 bile acids (including glycocholic acid, P = 0.04), and modulation of 4 indole derivative compounds (including indole lactic acid, P = 0.01). Fasting serum samples after 2 wk of daily intake of milk or yogurt could also be differentiated based on their metabolic profiles (OPLS-DA Q2 = 0.56) and were discussed in light of the postprandial results.Conclusion: Metabolic pathways related to amino acids, indole derivatives, and bile acids were modulated in healthy men by the intake of yogurt. Further investigation to explore novel health effects of fermented dairy products is warranted.This trial was registered at clinicaltrials.gov as NCT02230345. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes mellitus (T2DM) is associated with coronary microvascular dysfunction in the absence of obstructive coronary artery disease (CAD). Cardiovascular magnetic resonance (CMR) T1-mapping at rest and during adenosine stress can assess coronary vascular reactivity. We hypothesised that the non-contrast T1 response to vasodilator stress will be altered in patients with T2DM without CAD compared to controls due to coronary microvascular dysfunction. Methods: Thirty-one patients with T2DM and sixteen matched healthy controls underwent CMR (3 T) for cine, rest and adenosine stress non-contrast T1-mapping (ShMOLLI), first-pass perfusion and late gadolinium enhancement (LGE) imaging. Significant CAD (>50% coronary luminal stenosis) was excluded in all patients by coronary computed tomographic angiography. Results: All subjects had normal left ventricular (LV) ejection and LV mass index, with no LGE. Myocardial perfusion reserve index (MPRI) was lower in T2DM than in controls (1.60 ± 0.44 vs 2.01 ± 0.42; p = 0.008). There was no difference in rest native T1 values (p = 0.59). During adenosine stress, T1 values increased significantly in both T2DM patients (from 1196 ± 32 ms to 1244 ± 44 ms, p < 0.001) and controls (from 1194 ± 26 ms to 1273 ± 44 ms, p < 0. 001). T2DM patients showed blunted relative stress non-contrast T1 response (T2DM: ΔT1 = 4.1 ± 2.9% vs. controls: ΔT1 = 6.6 ± 2.6%, p = 0.007) due to a blunted maximal T1 during adenosine stress (T2DM 1244 ± 44 ms vs. controls 1273 ± 44 ms, p = 0.045). Conclusions: Patients with well controlled T2DM, even in the absence of arterial hypertension and significant CAD, exhibit blunted maximal non-contrast T1 response during adenosine vasodilatory stress, likely reflecting coronary microvascular dysfunction. Adenosine stress and rest T1 mapping can detect subclinical abnormalities of the coronary microvasculature, without the need for gadolinium contrast agents. CMR may identify early features of the diabetic heart phenotype and subclinical cardiac risk markers in patients with T2DM, providing an opportunity for early therapeutic intervention. [ABSTRACT FROM AUTHOR]

We developed paper-based powder X-ray diffraction (PP-XRD) to implement phase identification and/or crystal structure determination on paper-based platforms. These aims are not possible with other paper-based detectors, such as Raman spectroscopy and mass spectrometry. PP-XRD overcomes these limitations. Here we reported the simple and low-cost in situ PP-XRD protocol for phase identifications of inorganic and organic materials. We demonstrated that sample amounts of lead nitrate on paper substrate can be reduced into 1/30 of conventional ones by using the standard glass substrate at the same signal-to-noise ratio (S/N) of the X-ray diffraction (XRD) pattern. The paper-based method was comparable in sample quantity and intensity with zero background holder method, even though single crystal Si(100) substrate as zero background holder was used for the specimen preparation of CTAB (C 19 H 42 BrN). More importantly, paper substrates helped reduce preferred orientation that was generally present in routine powder XRD. Also, combined with paper chromatography, overlap peaks were eliminated in the XRD detection patterns of lead nitrate and cobalt nitrate hexahydrate. This new PP-XRD protocol may accelerate the process to identify phase or determine the molecular structures of new materials using trace sample directly. It also includes a hyphenated technique of powder XRD with a simple paper-based microfluidic separation of chemical solutions. [ABSTRACT FROM AUTHOR]

By coupling shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) with paper chromatography, two birds with one stone method were developed for simultaneous on-site separation and optical detection of multiple components. The established method features high sensitivity of plasmon-enhanced sensing strategies and sufficient temporal and spatial resolution of planar chromatographic techniques. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple colourimetric µPAD for the real-time detection of bilirubin. • The developed µPAD can detect bilirubin concentrations up to 950 µM. • The detection is based on the formation of green-coloured copper-bilirubin complex. • Quantification of bilirubin using ImageJ software in RGB and LAB colour spaces. A paper-based colourimetric assay for the Point-of-Care Testing (PoCT) of bilirubin has been developed based on the formation of a green-coloured copper-bilirubin complex from a blue-coloured tetraamminecopper(II) sulphate complex. The reaction was studied and optimized by UV–Visible absorption spectroscopy and translated onto a paper strip. Hydrophobic circular well patterns on Whatman chromatography paper were created by wax printing. The tetraamminecopper(II) sulphate complex was drop cast and dried on the reagent zones in the wax-patterned paper. The images of reagent zones captured using a scanner were analyzed using ImageJ software. Bilirubin spiked blood serum was tested in the concentration range of 1.2 to 950 µM. The PAD exhibited sensitivities of 0.4197 a.u/μM and 0.1040 a.u/μM for concentration ranges of bilirubin 1.2 to 96 μM and 105 to 950 μM respectively and a low detection limit of 0.799 µM. The method is highly selective to bilirubin, even in the presence of other biomarkers in serum. A plasma separation membrane incorporated PAD was fabricated for the final testing and quantification of bilirubin from whole blood. [ABSTRACT FROM AUTHOR]

We developed an electrochemical paper-based device (ePAD) for the online separation and simultaneous determination of structurally similar carbofuran (CBF) and carbaryl (CBR). Our device combined paper chromatography and an electrochemical sensor as a single system for increasing the selectivity to simultaneous detection of the two pesticides. During the simultaneous detection of CBF and CBR, the separation of the two carbamate compounds depends on the differences between the movements of the substances on the chromatographic paper in the moving phase flow. The isolated pesticides were electrochemically measured using an amperometric method. Under optimal conditions, which include the effect of the mobile phase, separation channel, and the applied potential, the proposed device provides a linear range for the simultaneous determination of CBF and CBR from 0.1 to 2.0 and 0.5–7.5 mg L−1, with the limits of detection at 0.06 and 0.40 mg L−1, respectively. Furthermore, we successfully used the developed device to determine CBF and CBR in water, cucumber, and cabbage samples. The obtained results correspond to results obtained from a standard method. This developed ePAD is low-cost and uses a low sample volume (2 µL). Moreover, it is disposable, portable, and a promising tool for the on-site quantification of pesticides in actual samples. • Paper chromatography integrated with electrochemical detection (ePAD) is highlighted. • A separation-based ePAD was first developed for detection of CBF and CBR pesticides. • Online separation and simultaneous detection of structurally similar compound were achieved. • The ePAD provides highly selective and sensitive detection of CBF and CBR. • This sensor was successfully applied to determine CBF and CBR in real samples. [ABSTRACT FROM AUTHOR]

The surface azide content of polymeric nanoparticles (latex) was measured in three steps: 1) conjugating an alkyne derivative of Rhodamine (Rho-Alk); 2) using paper chromatography to separate the immobile latex particles from unreacted fluorophore; and, 3) on-paper fluorescence quantification of the latex-bound Rho-Alk. Paper chromatography with methanol elution was effective because the nanoparticles did not migrate during elution, whereas the unreacted dye did. This assay can be used to estimate the coupling yield of any alkyne simply by conducting a second stage click reaction with Rho-Alk to determine the content of azides not consumed in the first click reaction. [ABSTRACT FROM AUTHOR]

DNA extraction efficiency affects the success of PCR-based method applications. The Punch-it™ NA-Sample kit for extracting DNA by using paper chromatography is technically easy to use and requires just two reagents and only 10 min to complete. The Punch-it™ NA-Sample kit could be offered as a rapid, accurate, and convenient method for extracting bacterial and fungal DNA from blood culture bottles. We compared the efficiencies of the commercial kit (Punch-it™ NA-Sample kit) and an in-house conventional boiling method with Chelex-100 resin for DNA extraction from blood culture bottles. The efficiency of the two DNA extraction methods was assessed by PCR-reverse blot hybridization assay (PCR-REBA, REBA Sepsis-ID) for detecting Gram positive (GP) bacteria, Gram negative (GN) bacteria, and Candida species with 196 positive and 200 negative blood culture bottles. The detection limits of the two DNA extraction methods were 10 3 CFU/mL for GP bacteria, 10 3 CFU/mL for GN bacteria, and 10 4 CFU/mL for Candida . The sensitivity and specificity of the Punch-it™ NA-Sample kit by REBA Sepsis-ID were 95.4% (187/196) and 100% (200/200), respectively. The overall agreement of the two DNA extraction methods was 98.9% (392/396). Three of four samples showing discrepant results between the two extraction methods were more accurately matched up with the Punch-it™ NA-Sample kit based on conventional culture methods. The results indicated that the Punch-it™ NA-Sample kit extracted bacterial and fungal DNA in blood culture bottles and allowed extracted DNA to be used in molecular assay. [ABSTRACT FROM AUTHOR]

Besides hyperglycaemia and insulin resistance, several factors are associated with a higher cardiovascular risk in type 2 diabetes mellitus (T2DM), many of them being closely related to each other owing to common origins or pathways. The pathophysiological mechanisms underlying vascular dysfunctions in diabetes include reduced bioavailability of nitric oxide, increased ROS and prothrombotic factors production, as well as activation of receptors for advanced glycation end-products. These alterations contribute to create a pro-inflammatory/thrombotic state that ultimately leads to plaque formation and complication. This study aimed at identifying differentially expressed plasma proteins between T2DM and non-diabetic patients undergoing carotid endarterectomy, by means of two-dimensional electrophoresis coupled with LC-MS/MS. Before analysis, plasma samples were enriched in low-expression proteins through combinatorial hexapeptide ligand libraries. Both mono- and two-dimensional western blotting were performed for data validation. Differentially expressed proteins were mapped onto STRING v10 to build a protein-protein interaction network. Sixteen differentially expressed spots were identified with a high score. Among them, there were fibrinogen beta and gamma chains, complement C1r, C3 and C4-B subcomponents, alpha-1-antitrypsin (AAT), vitronectin and CD5 antigen-like. Protein-Protein interaction analysis evidenced a network among differentially expressed proteins in which vitronectin seems to represent a potentially pivotal node among fibrinolysis, complement dependent immune responses and inflammation in accordance with a number of in vitro and in vivo evidences for a contributory role of these proteins to the development of diabetic atherosclerosis. [ABSTRACT FROM AUTHOR]

The diagnosis of intermittent claudication (IC) is challenging. Imaging with radiopharmaceuticals provides a new method for detecting acute IC. Pentoxifylline improves blood flow to ischemic tissues via increasing erythrocyte elasticity and inhibiting platelet aggregation. Pentoxifylline was radio-iodinated with radioiodine-131 (131I) through a direct electrophilic substitution reaction. Furthermore, various factors that might influence the radiolabeling strategy were investigated. The radiochemical yield of [131I]iodopentoxiphyline was evaluated by using paper chromatography and HPLC methods. The biodistribution pattern of [131I]iodopentoxiphyline was studied, where Swiss albino mice was used as a model of acute limb ischemia-reperfusion. The maximum radiochemical yield of pentoxifylline was found to be 94.11 ± 2.35%. The biodistribution findings revealed that [131I]iodopentoxiphyline was significantly deposited at the ischemic site (left hind limbs), with encouraging target/non-target (T/NT) ratios. At 0.25 and 1 h post injection, the uptake of [131I]iodo-pentoxifylline was 5.30 ± 0.30 and 9.98 ± 1.12%, respectively. Also, the maximum T/NT ratio for [131I]iodo-pentoxifylline (9.45 ± 0.26) was obtained at 0.25 h post injection. Due to safety and selectivity, [131I]iodo-pentoxifylline may be a good prospective diagnostic tool for early identification of IC. Moreover, the outcome of this study can be expected to apply to I-123 as well. • Pentoxifylline radiolabeled with iodine-131. • Various factors affecting radiochemical yield percentage were studied. • In vivo biodistribution pattern of [131I]iodopentoxiphyline was studied. • [131I]iodopentoxiphyline showed a marked accumulation at the ischemic site. [ABSTRACT FROM AUTHOR]

• We developed a simple SYBR Green-based mtDNA qPCR method. • Experiments were performed following MIQE and other guidelines. • K562 DNA at 100 pg/µL was converted into 16,400 copies/µL mtDNA using plasmid DNA. • NIST SRM 2372a was quantified with differences of up to −35.0% for 1/10 solutions. • Precision, effects of PCR inhibitors, and cross-reactivity were evaluated. In forensic mitochondrial DNA (mtDNA) analysis, quantitative PCR (qPCR) is usually performed to obtain high-quality sequence data for subsequent Sanger or massively parallel sequencing. Unlike methods for nuclear DNA quantification using qPCR, a calibrator is necessary to obtain mtDNA concentrations (i.e., copies/µL). Herein, we developed and validated a mtDNA quantification method based on a SYBR Green assay by following MIQE [Bustin et al., Clin. Chem. 55 (2009) 611-22] and other guidelines. Primers were designed to amplify nucleotide positions 16,190–16,420 in hypervariable region 1 for qPCR using PowerUp SYBR Green and QuantStudio 5. The optimized conditions were 0.3 µM each primer and an annealing temperature of 60 °C under a 2-step cycling protocol. K562 DNA at 100 pg/µL was converted into a mtDNA concentration of 16,400 copies/µL using linearized plasmid DNA. This mtDNA calibrator was obtained by cloning the synthesized DNA fragments of mtDNA (positions 16,140–16,470) containing a 100-bp inversion. The linear dynamic range of the K562 standard curve was 10,000–0.1 pg/µL (r 2 ≥ 0.999). The accuracy was examined using NIST SRM 2372a, and its components A, B, and C were quantified with differences of −29.4%, −35.0%, and −22.0%, respectively, against the mtDNA concentrations calculated from published NIST data. We also examined the specificity of the primers, stability of the reaction mix, precision, tolerance against PCR inhibitors, and cross-reactivity against DNA from various animal taxa. Our newly developed mtDNA quantification method is expected to be useful for forensic mtDNA analysis. [ABSTRACT FROM AUTHOR]

Every day, thousands of diagnostic tests in nuclear medicine are performed on patients around the world wherein pertechnetate-based solutions are taken internally, requiring time-consuming quality controls. In this paper, we demonstrate the use of platinum ultramicroelectrodes coupled to differential pulse stripping voltammetry as an advantageous alternative to conventional quality control for radiopharmaceuticals using paper or thin-layer chromatography and gamma camera. Detection limits lower than 5 nM have been achieved during fast experiments in few minutes with ready-to-use pertechnetate-based physiological solutions. This method can be generic and transposed to other radiopharmaceuticals having an electrochemical activity at a potential different from each others. [ABSTRACT FROM AUTHOR]

Ascending paper chromatography of Hg+2has been performed with mixed acids as developing mobile phase. Effects of temperature, concentration, and composition of the mobile phase onRfvalues have been investigated. Hg+2has been selectively separated from several synthetic binary and multicomponent mixtures containing the toxic and heavy metal ions. Often these metal ions remain associated with it in its ores and alloy samples. Hg+2in trace level has been separated and detected from blood serum containing the congeners Zn+2, Cd+2, Pb+2, Bi+3, Th+4, Tl+3, and Cu+2. On the basis of the difference in the migration of the spots on the paper, twenty difficult separations have been achieved. Several thermodynamic parameters, ΔG, ΔH,and ΔShave been determined by differential variation of radii of the spot with respect to temperature utilizing the thermodynamic relationship. The partition equilibrium constant was also determined. Metal ions were detected by borohydride reduction on the paper strip. Separation factors have been correlated in terms of DesityFunctional (corrected hardness,η∗) Index. Fromη∗,hydrated radii of the metal ions have been determined. A plausible mechanism for the differential migration of diverse metal ions has been suggested. [ABSTRACT FROM PUBLISHER]

Two series of “papers” that were made from natural fibers and synthetic fibers, respectively, were examined for use in paper-spray mass spectrometry and the results were compared to chromatography paper that is currently being used. In the former case, four types of papers were used, including gampi paper, tengujou paper, glassine paper and cicada paper, and the findings show that the limit of detection can be improved when gampi paper was used. This is because gampi paper is very tough and extremely thin (thickness, <20 μm), which permits sample molecules to be translated and evaporated nearly instantly. Since ionization occurs within a very short period, an abundance of ions is formed, leading to a dramatic improvement in the limit of detection. Meanwhile, a series of tough, thin synthetic fibers, including a microarray membrane (hollow and fibrous) and nanofibers, were also tested. The papers were prepared from polycarbonate, polylactic acid and poly- l -lactic acid (PLLA), respectively, by means of a co-axial electrospinning technique. The findings show that the limit of detection also can be improved, when a PLLA nanofiber was used. This is because this type of paper-like nanofiber is also very thin, tough and hydrophobic, which permits to ionization to occur within a very short period. Detailed information on methods for synthesizing these fibers and their use in the analysis of a real sample are also reported. [ABSTRACT FROM AUTHOR]

A novel washing scheme following antigen–antibody reactions with analyte was used during construction of a fluorescent immunosensor to resolve the background problem in the lateral flow assay with human serum. An immuno-membrane strip was devised to simultaneously measure cardiac troponin I (cTnI), creatinine kinase-MB isoform (CK-MB), and myoglobin to diagnose acute myocardial infarction. This strip was then installed within a cartridge containing a built-in washing solution tank, which was used to supply the solution across the signal generation pad of the strip after the immune reactions. Such cross-flow washing was initiated by onset-signaling from the internal control and began to run automatically upon sample addition. Under optimal conditions, the immunosensor displayed a stably suppressed background baseline, enabling us to attain a low detection limit for cTnI (0.05 ng/mL) as well as favorable reproducibility for repetitive measurements (relative standard deviation <10%). No interference was observed among the different complex formations at the respective analyte sites, and no artifacts were caused by sample matrices. We tested the performance relationship with the Pathfast reference system for positive serum samples (36 for cTnI, 58 for CK-MB, and 17 for myoglobin), and the correlation coefficients were >0.98. This result suggests that the new immunosensor system based on two-dimensional chromatography can be used for clinical testing [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a method for production of yttrium silicate microspheres is reported. Yttrium silicate microspheres with approximate sizes of 20–50µm were obtained when an aqueous solution of Y(NO3)3 was added to tetraethyl orthosilicate (TEOS) and was pumped into silicone oil under constant stirring. The shapes of the particles produced by the proposed method were regular and nearly spherical. The spherical shapes, composition and element distribution were investigated by scanning electron microscopy (SEM), carbon/sulfur analysis and SEM/EDS mapping analysis. Paper chromatography was used to identify radiochemical impurities in the radioactive microspheres. The radionuclide purity was determined using a gamma spectrometry system and an ultra-low-level liquid scintillation spectrometer. The results indicated that the proposed silicone oil spheroidization method is suitable for the production of yttrium silicate microspheres. [Copyright &y& Elsevier]

Paper chromatography was a big breakthrough in the early of 20th century but it is rarely used due to the long separation time and the diffusion on the sample spots. In this work, for the first time, a paper-based chemiluminescence (CL) analytical device combined with paper chromatography was developed for the determination of dichlorvos (DDV) in vegetables without complicated sample pretreatment. The paper chromatography separation procedure can be accomplished in 12min on a paper support (0.8×7.0cm2) by using 5µL sample spotted on it. After sample developing, the detection area (0.8×1.0cm2) was cut and inserted between two layers of water-impermeable single-sided adhesive tapes. The paper-based chip was made by attaching the middle layer of paper onto the bottom layer. Then it was covered by another tape layer, which was patterned by the cutting method to form a square hole (0.8×1.0cm2) in it. 10μL mixed solution of luminol and H2O2 was dropped on the detection area to produce CL. A linear relationship was obtained between the CL intensity and the concentrations of DDV in the range between 10.0ngmL−1 and 1.0μgmL−1and the detection limit was 3.6ngmL−1. Water-soluble metal ions and vitamins can be developed at different spatial locations relative to DDV, eliminating interference with DDV during detection. The paper-based chromatographic chip can be successfully used for the determination of DDV without complicated sample preparation in vegetables. This study should, therefore, be suitable for rapid and sensitive detection of trace levels of organophosphate pesticides in environmental and food samples. [ABSTRACT FROM AUTHOR]

Abstract: An overview is presented of the impact of chromatographic method developments on the quality control of pharmaceuticals as of the 1950s up until the present times. This survey is mainly based on the changes in pharmacopeias starting with United States Pharmacopeia (USP) 16, issued in 1960, up to the presently effective USP 34 and European Pharmacopeia 7.2. At the beginning of this period the role of chromatographic methods was negligible and was restricted to classical column chromatography and paper chromatography. However, the invention of high-performance liquid chromatography (HPLC) initiated a rapid paradigm shift in the attitude toward, and the use of, chromatographic methods. As a result, HPLC began a “career” of rapid spreading and development, and by now has undoubtedly become the principal method in pharmaceutical analysis. Likewise, the role of thin-layer chromatography (TLC) and to a lesser extent gas chromatography is also remarkable. The role of these and electrophoretic methods in the identification, assay and purity check of drugs and drug products in the modern pharmacopeias is discussed. As a case study the stability investigation of Depersolone® injection carried out in the 1960s and 35 years later is presented and the information obtainable from the classical and modern approach is compared. [Copyright &y& Elsevier]

Abstract: Objective: 99mTc-Sn-PYP (Technetium-99m labeled tin pyrophosphate) has been widely used as a radiopharmaceutical for bone scanning as well as in nuclear cardiology. It is also found in the body in trace amounts. 177Lu is presently considered as an excellent radionuclide for developing bone pain palliation agents. PYP is an analogue of MDP and MDP has been labeled with 177Lu. No study on preparing a complex of 177Lu with PYP has been reported yet. Based on these facts, it was hypothesized that a bone-seeking 177Lu-PYP (Lutetium-177 labeled Pyrophosphate) radiopharmaceutical could be developed as an agent for palliative radiotherapy of bone pain due to skeletal metastases. Methods: 177Lu was produced by irradiating lutetium foil (11 mg) natural target at a flux ∼1.0×1014n/cm2/s for 12 h in the swimming pool type reactor. 177Lu in the form of 177LuCl3 was labeled with PYP. The radiochemical purity and labeling efficiencies were determined by paper chromatography. Labeling of 177Lu with PYP was optimized and a labeled sample was subjected to HPLC analysis. To determine the charge on the 177Lu-PYP complex, radio-electrophoresis was conducted for 1 h under a voltage of 300 V and 45 mA current using 0.025 M phosphate buffer (pH 6.9). Bioevaluation studies with rabbit under γ-camera were also performed to verify the skeletal uptake. Results: The quality control using paper radio-chromatography has shown >99% radiochemical purity of 177Lu-PYP complex. Radio-chromatography also showed maximum labeling at ligand/metal ratio=60:1. HPLC analysis showed 1.42±0.01 min retention time of 177Lu-PYP complex. No decrease in labeling was observed at higher temperatures. Gamma-camera images of 177Lu-PYP in normal rabbit at 24 h post injection also showed high skeletal uptake. Conclusion: The study demonstrated that sodium pyrophosphate could be labeled with 177Lu with high radiochemical yields (>99%). Negatively charged 177Lu-PYP complex retained stability for a day and at high temperatures too. Gamma-camera images of 177Lu-PYP in normal rabbit at 24 h post injection showed high skeletal uptake, suggesting that it may be useful as a bone-pain palliation agent for the treatment of bone metastases. [Copyright &y& Elsevier]

Abstract: The novel levansucrase produced from Bacillus subtilis NRC1aza yielded two types of levan L1 and L2 with different molecular weights 85.23kDa and 31.95kDa, respectively. The levan identification was detected by paper chromatography and high-pressure liquid chromatography. The antioxidant activity of levan and their derivatives (SL1 and SL2) exhibited a strong free radical scavenging activity with DPPH. The antitumor activity of SL1 was tested against different human cancer cell lines. The cell death was explored mechanistically through evaluation of Apoptosis/necrosis ratio, DNA fragmentation, histone deacetylase activity, mitochondrial transmembrane potential (Δψ m ), cytochrome C release, total caspases, caspase-3, and caspase-9, and cell cycle. SL1 showed high selective cytotoxicity against HepG2 cells. SL1 led to DNA damaging and fragmentation that was associated with induced apoptosis via mitochondrial pathway, which initiated by the impairment of Δψ m and then increased mitochondria, released cytochrome c, that in turn activated caspase-9 and caspase-3 and induced apoptosis. [Copyright &y& Elsevier]

Abstract: Aims: Use of probiotics, alone or as adjunct to other established therapies, has been reported to have potential benefits. Recently, we have reported protective potential of probiotic against Salmonella-induced liver injury. However, co-supplementation with prebiotics did not result in meaningful synergism at systemic level. Owing to the action of probiotics at the mucosal level and of arginine at systemic level, the present study was designed to evaluate the effect of Lactobacillus plantarum alone or in conjunction with arginine to combat endotoxin-mediated liver injury in rats. Main methods: Bacterial endotoxin/lipopolysaccharide (LPS) was injected intraperitoneally and animals were sacrificed 8h post-challenge. Efficacy of L. plantarum alone or in conjunction with l-arginine was determined on the basis of enzyme markers, histology, levels of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) in addition to identification of amino acids by paper chromatography. Key findings: Prior supplementation of LPS-challenged rats with L. plantarum (1010 CFU per rat given orally for 10days) demonstrated decreased levels of liver enzymes, NO and TNF-α. Interestingly, complementing Lactobacillus with arginine revealed a synergistic decrease not only in the liver markers but also in NO and TNF-α along with increased intensity of ornithine and methionine. Histological evidence also confirmed the protective efficacy of probiotic in conjunction with l-arginine. Significance: Presence of ornithine and methionine in the probiotic-arginine co-supplemented group suggests involvement of arginase-induced synthesis of polyamines. This study highlights that L. plantarum may direct l-arginine metabolism towards polyamine synthesis thereby exhibiting synergistic effect against liver injury. [Copyright &y& Elsevier]

Abstract: We developed a convenient method by coupling frontal elution paper chromatography with desorption corona beam ionization mass spectrometry (DCBI-MS) for rapid determination of chlorphenamine added in herbal medicines or dietary supplements. In this method, the ethanol extract of the herbal products was spotted directly onto an isosceles triangular filter paper sheet, and then the paper sheet was developed under strong elution condition with the sample zone migrating at the solvent front. The analyte was finally condensed at the V-shaped tip which could then be placed under the visible plasma beam of DCBI for ionization. The overall procedure took less than 5min. The frontal elution paper chromatography on a triangular plate used in this work improved the signal intensity of chlorphenamine by 30-fold due to the analyte condensing at the tip and the reduction of the background suppression. Furthermore, the paper sheet also functioned as a filter in the analysis of solid or powder samples, which can increase the analytical throughput by omitting the step of centrifugation. The proposed method in current study was successfully applied in the determination of chlorphenamine in herbal medicines. Chlorphenamine was detected in four of the twelve types of herbal medicines examined in this study. The limit of detection was 200ng/mL (2.0ng absolute) in full-scan positive-ion mode and the linear range was from 5.0μg/mL to 50μg/mL with satisfactory linear coefficient (R 2 (the square of the correlation coefficient)=0.895). Good reproducibility was achieved with relative standard deviations (RSDs) less than 15.0% and the recoveries of chlorphenamine ranged from 84.3 to 90.6%. [Copyright &y& Elsevier]

Objective: To evaluate alternative methods for radiochemical purity testing of indium (In)-111 capromab pendetide after the discontinuation of instant thin-layer chromatography silica gel (ITLC-SG) strips. Design: Descriptive experimental study. Setting:United States in 2009. Participants: Not applicable. Intervention: Paper chromatography using Whatman 3MM strips, paper chromatography using Whatman 31ET strips, and mini-column chromatography using silica Sep-Pak cartridges were evaluated in the radiochemical purity testing of 13 consecutive vials of In-111 capromab pendetide prepared for clinical patient imaging procedures. These methods also were evaluated by testing seven aliquots of In-111 capromab pendetide that had been spiked with 5% In 15% In-111 pentetate (diethylene triamine peutaacetic acid). Main outcome measures: Correlation coefficients, radiochemical purity values for each method compared with ITLC-SG, and procedure times. Results: Correlation coefficients of 0.988.0.996. and 0.979 were found for ITLC-SG compared with Whatman 3MM, Whatman 31ET, and silica Sep-Pak, respectively. Compared with ITLC-SG, mean (±SD)) radiochemical purity values differed by -0.8 ± 0.6 (range -2.5 to 0.4) for Whatman 3MM, -0.8 ± 0.6 (-2.3 to 0) for Whatman 31ET, and -0.5 ± 1.2 (-3.6 to 0.7) for silica Sep-Pak. The approximate time required to develop the chromatography strip or elute the mini-column was 3, 14, 5, and 6 minutes for ITLC-SG, Whatman 3MM, Whatman 31ET, and silica Sep-Pak, respectively. Conclusion: All three methods evaluated were acceptable alternatives to ITLC-SG for radiochemical purity testing of In-111 capromab pendetide. Based on its slightly higher correlation to ITLC-SG. slightly tighter SD and range, and slightly shorter development time. Whatman 31ET is preferred in our facility. [ABSTRACT FROM AUTHOR]

Aim of the study: The antitussive Chinese herb Madouling derived from Aristolochia species is banned due to aristolochic acid-induced nephropathy. A substitute is found dispensed as Madouling in Taiwan. This study aims to determine the source plant and verify the antitussive properties of the Madouling substitute used in Taiwan. Materials and methods: Forensically informative nucleotide sequencing (FINS) approach based on the trnL-trnF and psbA-trnH regions was applied to facilitate identification of the genuine species and substitute. The antitussive effect of both genuine Madouling and the substitute were evaluated in guinea pigs. Results: FINS approach based on the trnL-trnF and psbA-trnH regions readily identified the sample of Madouling in Taiwan to the seeds of Cardiocrinum giganteum var. yunnanense. Ethanol extracts of the substitute showed significant antitussive properties in guinea pigs. Conclusion: Cardiocrinum seeds may have potential as a replacement of Aristolochia fruits. [Copyright &y& Elsevier]

Abstract: A selective method has been developed for the extraction chromatographic separation of lead (II) with Versatic 911 (liquid cation exchanger) coated on silanised silica gel. Lead (II) has been extracted from 0.1M acetate buffer at the range of pH 4.5–6.5. The effects of pH, flow-rate, stripping agents on extraction and elution have been investigated. Exchange capacity of the prepared exchanger at different temperatures with respect to lead (II) has been determined. The extraction equilibrium constant (K ex) and different standard thermodynamic parameters have also been calculated by temperature variation method. The effect of pH on R f values in ion exchange paper chromatography has been investigated. In order to investigate the sorption isotherm, two equilibrium models, the Freundlich and Langmuir isotherms, were analyzed. Lead (II) has been separated from synthetic binary and multi-component mixtures containing various metal ions associated with it in ores and alloy samples. The method effectively permits sequential separation of lead (II) from synthetic quaternary mixture containing its congeners Cu (II), Sn (II), Hg (II) and Cu (II), Cd (II), Bi (III) of the same analytical group. The method was found effective for removal and recovery of lead (II) from industrial waste and standard alloy samples following its preconcentration on the column. A plausible mechanism for the extraction of lead (II) has been suggested. [Copyright &y& Elsevier]

Abstract: Dopamine–HCl and l-DOPA-α-glycosides were prepared by reaction with cyclomaltohexaose, catalyzed by Bacillus macerans cyclomaltodextrin glucanyltransferase. The reaction gave maltodextrins attached to dopamine and l-DOPA; the maltodextrins were trimmed by reactions with glucoamylase and β-amylase to produce α-glucosyl- and α-maltosyl-glycosides, respectively. The glucoamylase- or β-amylase-treated dopamine- and l-DOPA-α-glycosides were fractionated and purified by BioGel P-2 gel-filtration column chromatography and preparative descending paper chromatography. Analysis by MALDI-TOF mass spectrometry and one- and two-dimensional NMR showed that the purified glycosides of dopamine and l-DOPA were glycosylated at the hydroxyl groups of positions 3 and 4 of the catechol ring. The major product was found to be 4-O-α-glycopyranosyl l-DOPA, and it was shown to be more resistant to oxidative tolerance experiments, involving hydrogen peroxide and ferrous ion, than l-DOPA. l-DOPA-α-glycosides are possibly more effective substitutes for l-DOPA in treating Parkinson’s disease in that they are more resistant to oxidation and methylation, which renders l-DOPA ineffective and deleterious. [Copyright &y& Elsevier]

Abstract: The routine method of paper chromatography includes five steps: spotting, separating, drying, spraying/immersing and color development. In this paper, a pre-staining paper chromatography which only consisted of spotting, separating and color development was developed for quantitative analysis of γ-aminobutyric acid. Compared to the routine paper chromatography, the improved method is clean, rapid, inexpensive and reproducible. The effects of ninhydrin concentration, color temperature, color time and Cu2+ concentration on the color yield in the ninhydrin reaction were optimized. And then the pre-staining paper chromatography coupled with vis spectrophotometry was applied to γ-aminobutyric acid quantification. The results indicated that the limit of detection was 0.05mgmL−1 and the linear range was from 0.5 to 20.0mgmL−1. Furthermore, an excellent correlation coefficient was observed with an R 2 =0.998. The method is accurate (RSD<2.64%), and has good recoveries (102.7–103.9%). The validation of the modified technique was verified by a HPLC method. [Copyright &y& Elsevier]

Abstract: In the proposed simple, disposable forced flow paper chromatographic device the main features of the separation like the analysis of time, separation power were improved. The chromatographic paper strips embedded into a polydimethylsiloxane (PDMS) block can be considered as an adsorption column, on which the liquid can be pumped. In a single device numerous separations can be performed in multiplex mode. On-capillary spectrophotometric detection is capable to detect the separated zones with good sensitivity. [Copyright &y& Elsevier]

Overexpression of folate synthesis and folate receptor in a wide variety of tumors was reported. As a result, folate derivatives have emerged as a potential candidate for tumor imaging and therapy. Ethopabate is a structural analogue of para-aminobenzoic acid (PABA), a precursor of folic acid. Ethopabate was radiolabeled with radioiodine-131 (131I) via direct electrophilic substitution reaction. Several factors that might affect the radiolabeling yield were studied. Paper chromatography was utilized for testing and evaluation of [131I]iodoethopabate, and HPLC was used as a co-chromatographic tool to confirm the radiochemical yield. The biodistribution of [131I]iodoethopabate in normal and tumor-bearing mice was investigated. The radioiodination of ethopabate resulted in a radiochemical yield of 93.70 ± 0.19%. The biodistribution data revealed that [131I]iodoethopabate was taken up by tumors with promising target/non-target (T/NT) ratios. Where, the tumor to-blood ratios were 3.30 ± 0.40 and 4.06 ± 0.10 at 1 and 4 h post injection, respectively. As a result of these findings, [131I]iodoethopabate appears to have excellent tumor uptake and adequate stability to be used for diagnostic purpose in the future. • Ethopabate was radiolabeled with 131I. • In vivo biodistribution study of [131I]iodoethopabate in normal and tumor bearing mice was performed. • Results showed a marked accumulation of [131I]iodoethopabate at tumor site. • The obtained data exhibited the possibility of using [131I]iodoethopabate as a selective targeting agent for tumor imaging. [ABSTRACT FROM AUTHOR]

• Microfluidic origami biosensor provided facile, low-cost platform for peanut allergen-Ara h1. • Aptamer-decorated black phosphorus nanosheets enhanced detection sensitivity. • Good sensitivity (0.05 µA·ng/mL) and low detection limit (21.6 ng/mL) were achieved. • Black phosphorus nanosheets provided more catalytic active sites and large surface area. • Microfluidic origami aptasensor demonstrated the potential for point-of-need testing. In this study, an origami microfluidic electrochemical nano-aptasensor was developed for the rapid detection of the peanut allergen Ara h1. Specifically, the microfluidic aptasensor was fabricated through sequential folding of a piece of chromatography paper substrate patterned with microchannel and screen-printed electrodes. Aptamer-decorated black phosphorus nanosheets (BPNSs) were electrodeposited onto the paper-based electrode surface as sensing probes for enhanced electrochemical detection and high specificity and selectivity. Critical design parameters (the concentration of probe, time for self-assembly of aptamer and reaction time) were investigated to optimize the aptasensor performance. The prepared aptasensor was able to complete detection within 20 min and demonstrated a linear range from 50 ~ 1000 ng/mL with a detection limit of 21.6 ng/mL. The aptasensor was successfully used to detect the Ara h1 spiked cookie dough sample. The proposed method reduces the gap between complex lab testing and food allergen analysis at the point of need. [ABSTRACT FROM AUTHOR]

[Display omitted] • Turmeric and tartrazine were used to adulterate cassava flour. • CIELab and dye screening enabled dyes used to adulterate flour to be differentiated. • The presence of curcuminoids/tartrazine in cassava flour were corroborated by HPLC. • A classification tree for the quality control of cassava flour was developed. A variety of methods for producing cassava flour exist, resulting in very heterogeneous products that exhibit various colours, textures, granulometries, and flavours. To improve its attractiveness to consumers, some producers dye cassava flour with turmeric or tartrazine; however, this practice is illegal in Brazil. In this study, cassava flour samples were collected and evaluated for possible adulteration by the addition of dyes. Flours were analysed by CIELab and dye screening (paper chromatography and the turmeric-identification method) and a classification tree was developed using these data. Positive results for curcuminoid pigments or tartrazine were confirmed by HPLC-DAD or HPLC-UV–Vis, respectively. The developed approach is an innovative alternative chemometric-analysis method that facilitates highly practical screening; adulterated cassava flour, a product of great human-food importance, can be identified using CIELab parameters. [ABSTRACT FROM AUTHOR]

Over the past decade there has been a renewed interest in research and development of both dietary and nutritional supplements. Significant advancements have been made in the scientific assessment of the quality, safety, and efficacy of these products because of the strong interest in and financial support of these projects. As research in both fields continues to advance, opportunities to use new and innovative research technologies and methodologies, such as proteomics and metabolomics, are critical for the future progress of the science. The purpose of the symposium was to begin the process of communicating new innovative proteomic and metabolomic methodologies that may be applied by researchers in both the nutrition and the natural product communities. This symposium highlighted 2 proteomic approaches, protein fingerprinting in complex mixtures with peptoid microarrays and top-down mass spectrometry for annotation of gene products. Likewise, an overview of the methodologies used in metabolomic profiling of natural products was presented, and an illustration of an integrated metabolomics approach in nutrition research was highlighted. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: The aims of this study were to label the versatile amino acid l-lysine with 99mTc using 2,3-dimercapto-succinic acid (DMSA) as a chelator, and to assess its tumor imaging feasibility under in vivo and in vitro conditions, and finally to determine the subcellular biodistribution of this radiopharmaceutical. Materials and Methods: DMSA-l-lysine was chemically synthesized and labeled with sodium pertechnetate. Nuclear magnetic resonance (NMR) and mass spectral analysis of DMSA-l-lysine were conducted. Radiochemical purity was determined by thin-layer chromatography (TLC) and paper chromatography. Cellular uptake, competition and subcellular localization studies were performed in rat breast cancer cells (13762). In vivo studies of planar imaging and biodistribution studies were performed on female Fischer 344 rats. Medical Internal Radiation Dose (MIRD) dosimetry estimates were calculated. Results: Radiochemical purity (determined by radio-TLC and high-performance liquid chromatography) of these compounds was >95%. 99mTc-DMSA-l-lysine showed good uptake in in vitro cell culture assays and uptake was reduced in competition studies. 99mTc-DMSA-l-lysine accumulates in the nucleus as much as in the cytoplasm and it was also shown that accumulation of the 99mTc-DMSA-l-lysine in the nucleus increases as a function of a time. There was an increase in tumor-to-blood and tumor-to-muscle count density ratios. Tumor/background ratios were 5.75 at 1 hour and 6.87 at 2 hours. In vivo tissue distribution studies revealed that radiation dosimetry of blood-forming organs were within radiation dose limits. Conclusion: DMSA-l-lysine kits can be labeled with 99mTc easily and efficiently, with high radiochemical purity and cost-effectiveness. In vitro cellular uptake and scintigraphic imaging studies demonstrated the pharmacokinetic distribution and feasibility of using 99mTc-DMSA-l-lysine for tumor imaging. [Copyright &y& Elsevier]

The water-soluble acidic polysaccharide from Thalassodendron ciliatum (Forss.) den Hartog was successfully extracted, fractionated and purified. The phytochemical profile of the two water-soluble fractions (F1 and F2), were detected using different analytic techniques. GC-MS analysis revealed the presence of 22 saccharide. Acidic polysaccharide, galacturonic and glucuronic acid were the most abundant. Moreover, paper chromatography and electrophoresis also performed as a preliminary chemical characterization of the polymer. The hepatoprotective activity of the fractions against thioacetamide (TAA) induced liver failure; antioxidant potential and preliminary immunomodulatory activity were assigned in-vivo. The results revealed a potent competence to improve the liver function profile (ALT, AST, total bilirubin, total glyceride, etc.) and a remarkable improvement in liver architecture in comparison to the challenged intoxicated groups. Moreover, they showed high anti-oxidative properties and a promising immunomodulatory influence via Il6. These findings provide new insight into the possible role of polysaccharide purified two fractions in the treatment of acute liver injury. [Display omitted] • For the first time Thalassodendron anionic polysaccharide were studied. • Moisture content, lipids content and low molecular weight carbohydrate were estimated. • The polysaccharide composed of galactouronic, glucouronic, glucose and mannose, arabinose, fructose and sucrose. • In-vivo study of the hepatoprotective activity, histopathology sections and liver function profile tests were performed. • The polysaccharide fractions reveal a remarkable hepatoprotective activity, high anti-oxidative and immunomodulatory effect. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) and its halogenated analogs tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA) are common environmental contaminants and a method for their simultaneous determination is urgently needed. A paper-based analytical device (PAD) was prepared using a metal-organic framework of UiO-66-NH 2 coated with molecularly imprinted polymers (MIPs) using TBBPA as a template. The maximum adsorption capacity was 120.94 mg g−1 and the imprinting factor was 4.07. The selective recognition ability of this PAD enabled the effective separation of TBBPA, TCBPA and BPA based on paper chromatography. Subsequently, the PAD cut into segments were used individually to determine the presence of target chemicals using a highly sensitive fluorescent method. Under ultraviolet light irradiation, UiO-66-NH 2 acts as a photocatalyst to produce reactive oxygen species (ROS) that degrade TBBPA, TCBPA or BPA in the imprinted cavities and the fluorescent signal of 2′,7′-dichlorodihydrofluorescein diacetate (H 2 DCFDA) added as a ROS probe enabled the indirect determination of target chemicals. This method could determine BPA and its halogenated analogs in dust samples simultaneously with detection limits ranging from 0.14 to 0.30 ng g−1. The intraday relative standard deviation (RSD) was ≤6.8% and interday RSD was ≤8.1%. The recoveries ranged from 91.0 to 105.6% with RSD values that were ≤7.5%. The results stemmed from this method were consistent with those obtained from LC-MS/MS. It is an environmentally-friendly approach due to the degradation of target pollutants and possesses many advantages such as high selectivity, low cost and easy-to-fabrication. [Display omitted] • MIP@UiO-66-NH 2 @paper was fabricated for developing a paper-based analytical device. • The paper-based analytical device integrated recognition, separation and detection. • Paper chromatography achieved the separation of TBBPA, and TCBPA and BPA. • An environmentally-friendly method was proposed for the simultaneous detection of BPA and its halogenated analogs. [ABSTRACT FROM AUTHOR]

• ECL was coupled with paper chromatography for separation and detection of DBP and BPA. • The synthesis of CdSe quantum dots was optimized based on PL spectra and ECL emissions. • The carbon tape working electrodes was modified with MWCNTs and CdSe quantum dots. • The filter paper was modified with chitosan and integrated in the paper-based analytical device. [Display omitted] Electrochemiluminescence (ECL) is a powerful technique with the advantages of high sensitivity and a wide dynamic range. However, most of previous strategies based on ECL could only detect one analyte so that it is inevitable to investigate the selectivity and influences of interferences. Herein ECL integrated with paper chromatography was showed to be a potential platform for separation and detection of two environmental hormones (bisphenol A, BPA, and dibutyl phthalate, DBP). In our approach, carbon conductive tape was attached to an ITO glass and then modified with multi-walled carbon nanotubes (MWCNTs) and CdSe quantum dot (CdSe QDs) to fabricate the working electrodes for ECL detection. The synthesis of CdSe QDs was optimized based on their photoluminescence spectra and the ECL intensities. The modified electrode was then coupled in the paper-based analytical devices consisting of the filter paper modified with chitosan. Based on their quenching effect on the ECL emission of CdSe QDs, excellent linear relationships could be obtained between decreased ECL intensities and both the concentrations of DBP and BPA. Besides, DBP and BPA could be separated based on their retention time by tilting the filter paper for 30° and then detected with ECL. This study suggested that paper-based analytical devices could be potentially applied for separation and detection of multiple targets due to their ease of fabrication and convenient operation. [ABSTRACT FROM AUTHOR]

Herein, Microfluidic Paper-based Analytical Devices (μPAD) strips, also called microstrips, have been fabricated using a fused-deposition modeling (FDM) based 3D printer. A polycaprolactone (PCL) filament on a chromatography paper was harnessed to create hydrophobic boundaries of a microchannel. A pair of screen-printed electrodes, with known separation, were integrated on the microchannel to measure the time taken for fluid automatically. A mini electronic sub-system, amenable to connect with an android smartphone, consists of an easily programmable microcontroller, Bluetooth module and voltage booster circuit. The pluggable-and-playable disposable microstrip was utilized to measure the viscosity of various biological samples with an accuracy of >92% with respect to a benchtop viscometer. In particular, the protein denaturation of Bovine Serum Albumin (BSA) and Lysozyme, and viscosity variation of human saliva have been observed. With a competency to measure the viscosity between 0.5 cP to 10 cP, platform cost of 92%. [ABSTRACT FROM AUTHOR]

• First assessment of paper chromatography using large sample sizes and microbe DNA. • Chromatogram features did not vary consistently with gradients of soil condition. • Results imply context dependent response of chromatogram features to soil condition. • Paper chromatography needs more testing before being embraced for soil assessment. Although paper chromatography is being promoted as a cost-effective tool for rapid assessment of soil health, few studies have explored the quantitative relationship between chromatogram features and soil health variables, and no studies have investigated the association between chromatogram features and microbial diversity as determined using DNA sequences. We assessed 343 soil samples from varying land uses in southwestern Australia to investigate the relationship between total organic carbon, microbial activity and diversity, salinity and pH levels and 12 chromatogram features. Spearman's correlations and variance partitioning were used to detect relationships. Although total organic carbon and microbial activity displayed the strongest correlations with chromatogram features, they were not associated with greater development of radial features and median zone radius as expected. This was in contrast to what has been previously reported, implying context dependent responses of chromatogram features to gradients in soil variables. Microbial community structure was found to explain changes in chromatogram features better than the measured soil variables. These results indicate that further studies are necessary before paper chromatography is embraced as a tool for soil health assessment, and raises questions regarding the use of chromatography by community groups as a tool to measure soil health. [ABSTRACT FROM AUTHOR]