Search

In this study, total phenolic contents and antioxidant activity were determined in various products made from two cultivars of jamman fruit (Eugenia jambolana) i.e. improved (V1) and indigenous (V2). Five products were made from each cultivar such as jam, squash, ready-to-drink juice, pulp powder and seed powder. Fruit cultivars were endogenous to the typical region of Sindh-Pakistan. Total phenolic contents were analyzed by Folin-Ciocalteu colorimetric method, whereas, the total antioxidant activity was analyzed by using the 2, 2-diphenil-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The highest total phenolic contents and antioxidants were observed in freeze dried seed powder while the lowest contents were found in squash.

In this report we demonstrate the use of Citrus japonica (CJ) leaf extract for the first time as biological liquid to work as capping as well as reducing agent for synthesizing extremely stable silver nanoparticles (AgNPs) from its precursor silver salt. Different parameters such as pH, speed of reaction, silver salt concentrations and leaf extract were optimized for the formation of CJ-AgNPs. CJ-AgNPs were then characterized through techniques like Ultra-violet visible (UV–Vis) spectroscopy, Fourier transform infra-red (FTIR) spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), Zeta-potential analysis (ZPA) and dynamic light scattering (DLS). As-formed CJ-AgNPs were verified as highly sensitive, extremely selective, stable, economical, eco-friendly and rapidly responsive colorimetric sensor for Hg2+ detection based on color change in solution from yellow to brownish. The dynamic range of developed sensor worked linearly in the range of 0.3–7.3 µM with R2 value of 0.999 and limit of (LOD) and limit of quantification (LOQ) as 0.09 µM and 0.30 µM respectively. The sensor demonstrated negligible interference under the influence of ions like Mg2+, Zn2+, Cu2+, Co2+, Pb2+, Cd2+ and Fe2+ and corresponding anions. The developed sensor was successfully applied to detect Hg2+ at low level in some real water samples.

To attain maximum recovery of useful compounds from slaughterhouse waste (Suet, Tongue, Pancreas) of selected ruminant (cow, goat, lamb, and bull), the fat extraction efficiency of popular methods was compared along with fatty acid (FAs) composition. Four selected methods including Soxhlet (SOX), acid hydrolysis, Bligh & dyer (B&D), and Folch (FOL) were assessed. After methylation, extracted lipids were analyzed by Gas chromatography for FA composition. Data indicated that all selected methods were significantly (p < 0.05) different from each other, particularly higher differences were noticed for low lipid-containing products (Tongue, Pancreas) as well as their respective FA Composition. Based on Analysis of Variance and Principal component analysis, the effective method for lipid and FA Composition analysis was the FOL method. The Soxhlet method was only effective for samples with high-fat content i.e., suet, while the B&D method gave comparatively low lipid content in analyzed samples. Hence based on the results, excellent fat and fatty acid extraction was achieved with the FOL method.

Polymer capped metal nanoparticles have been used for numerous biomedical and analytical applications. In present study, highly stable gold nanoparticles (AuNPs) capped with polypropylene glycol (PPG) were synthesized using chemical reduction method. The characterization of PPG-AuNPs was accomplished by atomic force microscopy (AFM), zetasizer, fourier transform infrared spectroscopy (FT-IR) and UV–vis spectroscopy. Furthermore, PPG-AuNPs were utilized as colorimetric probe for third generation cephalosporin antibiotic, ceftriaxone (CEF). PPG-AuNPs permitted efficient, selective, quantitative and rapid recognition in concentration range of 0.1–100 μM in presence of numerous other drugs and salts. PPG-AuNPs have great potential for quantitative recognition of ceftriaxone in biological and environmental samples. Moreover, the developed sensor has capacity to be applied as quality control of pharmaceutical formulations containing ceftriaxone. The PPG-AuNPs based sensor permits quantitative and fast recognition of ceftriaxone away from a sophisticated laboratory setup.

In this study, a biodegradable natural polymer chitosan was modified with salicylaldehyde to prepare salicylaldehyde functionalized chitosan nanoparticles (N-Ch-Sal). The N-Ch-Sal was characterized by atomic force microscopy (AFM), scanning electron microscopy-energy-dispersive X-ray (SEM-EDX), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The salicylaldehyde functionalized chitosan nanoparticles (N-Ch-Sal) (~80 nm) were then used for the adsorption of three heavy metals viz., Cu(II), Cd(II) and Pb(II) ions. The above-mentioned techniques were also employed for evaluation of changes in N-Ch-Sal after metal adsorption. The parameters affecting the adsorption of metal ions including pH, contact time, amount of adsorbent, initial metal ion concentration and the effect of interfering ions, were studied thoroughly and optimized. The concentration of metal ions remaining in the aqueous system after adsorption experiments was analyzed by ICP-MS. At optimal conditions, sorption capacity of Pb(II) ion was found to be highest i.e., 123.67 followed by Cu(II) (84.60) and Cd(II) (63.71 mg/g). The adsorption process followed the pseudo-second-order kinetic model and fitted well with the Langmuir adsorption isotherm. The adsorption method was applied to a real tap water sample for the quantification and removal of Pb(II) ions. The concentration of Pb(II) ions in the tested sample was 4.88 ppb.

In this study, we prepare synthetic arsenic-imprinted polymer (As-IP) by simple precipitation polymerization method by using 4-vinyl pyridine and 2-hydroxyethyl methacrylate as ligand and functional monomer use for the selective elimination of arsenic (As3+) from the aqueous environment. To achieve maximum sorption capacity several factors, i.e., pH, agitation time, shaking speed and sorbent dose were optimized. This prepared polymer was characterized by using SEM, EDX and FT-IR. Adsorption isotherm and kinetic data of As3+ follow the Langmuir isotherm and pseudo-second-order kinetic model. The maximum sorption capacity of As-IP is 106.3 mg/g. The limit of detection and limit of quantification were found to be 0.87 and 2.9 µg/L, respectivley. The relative selectivity factors of As-IP as compared to NIP for As3+/Cr3+, As3+/Al3+, As3+/Ni2+, As3+/Cu2+, As3+/NO3−, As3+/PO43− and As3+/SO42− were 1.445, 1.779, 1.469, 1.168, 1.481, 1.802 and 2.367, respectively. The adsorption efficiency of As3+ ions by using As-IP from real water samples was approximately 99% which shows that As-IP has good sorption capability and highly selective for the extraction of arsenic ions. Graphical representation of As-IP

Background: Liquid chromatography is the workhorse of analytical laboratories of pharmaceutical companies for analysis of bulk drug materials, intermediates, drug products, impurities and degradation products. This efficient technique is impeded by its long and tedious analysis procedures. Continuous efforts of scientists to reduce the analysis time resulted in the development of three different approaches namely, HTLC, chromatography using monolithic columns and UHPLC. Methods: Modern column technology and advances in chromatographic stationary phase including silica-based monolithic columns and reduction in particle and column size (UHPLC) have not only revolutionized the separation power of chromatographic analysis but also have remarkably reduced the analysis time. Automated ultra high-performance chromatographic systems equipped with state-ofthe- art software and detection systems have now spawned a new field of analysis, termed as Fast Liquid Chromatography (FLC). The chromatographic approaches that can be included in FLC are hightemperature liquid chromatography, chromatography using monolithic column, and ultrahigh performance liquid chromatography. Results: This review summarizes the progress of FLC in pharmaceutical analysis during the period from year 2008 to 2017 focusing on detecting pharmaceutical drugs in various matrices, characterizing active compounds of natural products, and drug metabolites. High temperature, change in the mobile phase, use of monolithic columns, new non-porous, semi-porous and fully porous reduced particle size of/less than 3μm packed columns technology with high-pressure pumps have been extensively studied and successively applied to real samples. These factors revolutionized the fast high-performance separations. Conclusion: Taking into account the recent development in fast liquid chromatography approaches, future trends can be clearly predicated. UHPLC must be the most popular approach followed by the use of monolithic columns. Use of high temperatures during analysis is not a feasible approach especially for pharmaceutical analysis due to thermosensitive nature of analytes.

In the present study, As3+ imprinted polymer as an active detoxification material has been synthesized through microwave assisted preparation method. By inducing the microwave radiation during the polymerization process decreases the reaction time to about 10 folds than conventional method. The imprinted polymer is one of the best possible techniques for the removal of arsenic, and various other contaminants from drinking water. The SEM and FTIR analyses have been conducted to clarify microstructure, surface morphology and size distribution of the synthesized imprinted polymer. The main parameters affecting the pzc, pH, agitation time, shaking speed, concentration, the temperature of adsorbent and percent of sorption, have been examined and optimized by Taguchi design. Taguchi L9 orthogonal array was employed to optimize the important factors versus % sorption values with nine experimental runs at 3 levels. Moreover, to understand the reaction phenomenon Langmuir and Freundlich isotherms, kinetic models and thermodynamics of adsorption process were calculated. The relative selectivity coefficient of imprinted polymer for As3+/Cd2, As3+/Zn2+, As3+/Ni2+were respectively 45.93, 131.01, 262.63 times greater than for non-imprinted polymer. The limit of detections (LOD) and limit of quantification (LOQ) of the proposed procedure for As3+ ion was found to be 1.0 µg/L and 3.3 µg/L for the As3+ ion respectively, with the relative standard deviation (RSD) of 4%. The excellent adsorption performance along with their low cost and convenient synthesis makes this range of adsorbent highly promising for commercial applications in drinking water purification and water treatment.

The present study describes a simple and facile precipitation polymerization technique. For the synthesis of Cd2+ion-imprinted polymer for the selective detoxification of toxic Cd2+ ions from the aqueous samples. The resultant Cd2+-imprinted polymer was characterized by the EDX, SEM, and FTIR. Different parameters were optimized during the adsorption study to achieve the maximum adsorption capability i.e. pH, equilibrium time, temperature shaking speed, and adsorbent dose. The maximum adsorption capacity of Cd2+ion-imprinted polymer was 62.9 mg. g−1 at pH 6. The kinetic study was best defined by pseudo-second-order, while the Langmuir isotherm model well fitted to present data. Good linearity was achieved in (10–100 μg. L−1) concentration range with LOD 0.88 μg. L−1 and LOQ 2.95 μg. L−1. The relative selective factor (K’) of Cd2+-ion and interfering ions was greater than 1 due to the imprinting effect. The developed method was validated by the spiking addition method and obtained good results in accordance with spiking values in real samples. The synthesized ion-imprinted polymer shown higher adsorption capacity than previously reported methods for the selective removal of Cd2+-ions from aqueous samples.

Sensitive cathodic stripping voltammetric methods have been developed for two fluoroquinolone antibacterial drugs, norfloxacin and enoxacin. Dimethylformamide (DMF) and 0.1 M hydrochloric acid were used as media for norfloxacin and enoxacin respectively. Potassium chloride was used as base electrolyte. A reduction wave was observed for norfloxacin within the range of -1.02 to -1.13V and for enoxacin within -0.93 to -1.07V. Linear calibration ranges for norfloxacin and enoxacin were observed within 20-100μg/mL and 1-40μg/mL with detection limits of 10μg/mL and 50ng/mL respectively Relative standard deviations (RSD) for the analysis of 10μg/mL norfloxacin and 10μg/mL enoxacin (n=5) were observed 1.l% and 0.2%. The presence of glucose, lactose, sorbitol, gum arabic, starch, magnesium stearate, methylparaben and propylparaben did not affect the determination. The methods were used for the analysis of pharmaceutical preparations and quantitative recoveries were obtained with relative deviation within 1.6-4.75%.

Human body is greatly exposed to aluminum due to its high abundance in the environment. This nonessential metal is a threat to the patients of chronic renal disorders, as it is easily retained in their plasma and quickly accumulates in different tissues. Thus, there is great need to remove it from the aqueous environment. In this study, Al3+ imprinted semiinterpenetrating polymer network (semi-IPN)-based cryogel composite was prepared and applied for the purification of environmental and drinking water samples from aluminum. Poly (2-hydroxyethyl methacrylate) (pHEMA) discs were produced via cryogenic treatment and imprinted semi-IPN was introduced to the 3-(trimethoxysilyl) propyl acrylate-modified macroporous cryogel discs. The adsorption properties and selectivity of the aluminum (III) imprinted semi-IPN cryogel composite were studied in detail. The imprinted semi-IPN cryogel composite showed good selectivity towards aluminum (III) ions with the imprinting factor (IF) of 76.4 in the presence of competing copper (II), nickle (II), and iron (III) ions. The maximum adsorption capacity of 271 mu mol g(-1) was obtained for aluminum (III) at pH 7.0 within 10 min using imprinted semi-IPN cryogel composite. The good selectivity and reusability of aluminum (III)-imprinted semi-IPN cryogel composite makes this material an eligible candidate for the purification of drinking water from aluminum (III) leaving important minerals remained in the water.

Apricots (Prunus armeniaca L.) are valuable resources for functional foods and nutraceuticals. Recently, apricot seed/kernel has become popular as a nonconventional source of high-oleic oil. Different extraction techniques have been used to extract oil from the apricot kernel; however, cold pressing is reported to retain a higher level of bioactive components in apricot kernel oil (AKO). Cold pressed AKO is known as a good source of edible quality vegetable oil due to its nutritionally important fatty acids such as oleic and linoleic acids. Among various minor bioactives such as tocopherols, phenolics, and carotenoids, amygdalin (glycosides) is detected in AKO, which are of great value due to their anticancer and antiinflammatory properties. AKO is employed as a major constituent in cosmetic products, high-quality toilet soaps, lip balms, and creams. Owing to increased awareness, nowadays consumers prefer to use cold pressed vegetable oils due to their better organoleptic flavor/aroma and better oxidative stability as compared with solvent extracted oils. This chapter aims mainly to explore the nutritional and nutraceutical prospects of AKO with a special focus on the use of cold pressing as a means of oil extraction. Moreover, fatty acids and minor bioactives compositions of AKO along with its food science and health-promoting attributes are also highlighted.

The increased complexity of sample matrices resulted in the requirement of specific and sensitive molecular recognition systems. Although molecular imprinting is an old idea, its potential as molec...

Development of novel materials for different analytical applications such as optical sensors is one of the major topics of modern scientific research. In this study, a nanosensor based on highly stable silver nanoparticles (AgNPs) conjugated with polystyrene-block-poly(2-vinyl pyridine) [PS-b-P2VP or P(S-VP)] copolymer was synthesized using two-phase one pot protocol. The nanosensor was characterized by UV–vis spectroscopy, zetasizer, FTIR and AFM. Polystyrene-block-poly(2-vinylpyridine)-conjugated silver nanoparticles [P(S-VP)-AgNPs] were further utilized as colorimetric sensor for thiocarbamate pesticide, cartap. P(S-VP)-AgNPs nanosensor allowed for rapid and quantitative detection of cartap in concentration range of 0.036–0.36 μgL−1 with detection limit as low as 0.06 μgL−1. The prepared sensor efficiently detected cartap in presence of other interfering pesticides. P(S-VP)-AgNPs demonstrated great potential for in situ detection of cartap in water and blood plasma.

In this study, a quantitative colorimetric sensing strategy is developed for the rapid, sensitive and selective determination of melamine. The sensing system relies on the application of succinic acid as a selective recognition probe functionalized over Ag NPs. The synthesized Ag NPs were modified with cysteamine to induce positively charged atmosphere which allowed easy and favorable functionalization of succinic acid. The di-carboxyl nature of succinic acid enabled its binding to both cysteamine and melamine. The strong and favorable linkage between succinic acids carbonyl and amine moieties of melamine triggered aggregation of silver NPs producing a significant shift in the measured absorption excitation. This change in the excitation along with the colorimetric response was found linearly proportional to the melamine concentration in the range of 0.1–1.2 μM. The developed sensor system is simple and unlike electrostatic attraction based sensor system utilize selective linkage for the recognition of melamine. In addition to this, the developed optical probe can efficiently be used for the determination of melamine in milk samples.

Egusi seed shells (ESS) were used as precursor for the preparation of two activated carbons (ACs) following H3PO4 and ZnCl2 activation. The effect of factors controlling the preparation of ACs such as chemical activating agent concentration (2 - 10 M), activation temperature (400°C - 700°C) and residence time (30 - 120 min) were optimized using the Box-Behnken Design (BBD). The optimized activated carbons based H3PO4 (ACP) and ZnCl2 (ACZ) were characterized by N2 adsorption, elemental analysis, atomic force microscopy (AFM), Boehm titration and Fourier transformed infrared (FTIR) techniques. The specific surface area was found to be 1053.91 and 1009.89 m2·g-1 for ACP and ACZ respectively. The adsorbents had similar surface functionalities and were both microporous. The effect of various parameters such as initial pH, concentration, and contact time on the adsorption of nitrate ions on ACP and ACZ in aqueous solution was studied. ACZ demonstrated better adsorption capacity (8.26 mg·g-1) compared to ACP (5.65 mg·g-1) at the same equilibrium time of 20 min. The adsorption process was governed by a “physical interactions” phenomenon for both adsorbents.

Interfacial polymerization (IP) is recently evolved method to fabricate solvent resistant nanofiltration (SRNF) membrane. Herein the preparation of SRNF is presented which involves the polymerization of piperazine (PIP) and trimesoyl chloride (TMC) on the surface of inert support i.e. Celgard 2400. The extent of interfacial polymerization (IP) on Celgard 2400 membrane was examined afterwards by different analytical techniques including atomic force microscopy (AFM), scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR). Their outcome revealed obvious surface modification of Celgard 2400 with thin and homogenous polyamide layer. Furthermore, the sugar (dextrose, sucrose and raffinose) solutions were passed from SRNF membranes to calculate the molecular weight cutoff (MWCO). Based on sugar rejection, the value of MWCO of SRNF membranes come in the range of nanofiltration (> 300 Da). An economical, chemical resistant, homemade NF Cell was fabricated to conduct permeation study through these membranes. Effect of various reaction conditions i.e. monomer concentrations, curing temperature and reaction time on the synthesis of SRNF membranes was optimized. Bromothymol blue (BTB) was selected dye in ethanol to permeate across SRNF membranes. The rise in monomer concentrations augments the rejection of BTB thereby declining ethanol flux, owing to more even surface coverage of Celgard 2400 membrane. Moreover, the reaction time and curing temperature affect the BTB rejection and ethanol flux in the same way. The pore size in SRNF membranes was estimated theoretically by Hagen-Poiseuille as ~0.59 nm. In conclusion, PIP-TMC monomeric system synthesized stable, homogenous and effective SRNF membranes with distinct rejection and flux values.

In present work chitosan functionalized magnetic nanoparticles (CMNPs) were successfully prepared and investigated for the removal of Reactive Orange 107 dye (RO 107) from water. The chitosan was extracted from shrimp shells (Penaeus merguiensis) and was characterized by solubility test and fourier transform infrared spectroscopy (FTIR). Degree of deacetylation of chitosan was examined by 1H-NMR and potentiometric titration method. Thereafter, the chitosan was used for synthesis of CMNPs. The synthesized CMNPs were characterized by FTIR, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), thermal gravimetric analysis (TGA) and atomic force microscopy (AFM). Effects of various variables such as contact time, pH, stirring speed, adsorbent dosage, temperature, and concentration of electrolyte on extraction efficiency were evaluated. Freundlich isotherm model fits better that shows the removal of RO 107 with CMNPs by multilayer adsorption behaviour. Furthermore, kinetic study showed that adsorption process followed pseudo-second order kinetic model regulated by chemisorption. Thermodynamic analysis explained that adsorption of RO 107 onto CMNPs was endothermic as well as spontaneous. The developed CNMPs were applied to environmental remediation of spiked RO 107 treated waste water samples with 96.20% removal potential, hence, offered an effective sorbent for removal of RO 107 contaminated water samples.

Herein we demonstrate a simplistic microwave assisted chemical precipitation approach regarding the synthesis of zinc oxide nanoparticles. As-prepared ZnO nanoparticles (NPs) were characterized by UV–visible spectroscopy, Fourier transform infra-red spectroscopy, atomic force microscopy and x-ray diffractometry and scrutinized as photo-catalysts for degradation of 4-chlorophenol (4-CP) under sunlight. The study substantiated that 98.5% of 4-CP was degraded within 20 min in the absence of initiator like H2O2 which reflects an outstanding prospective use for ZnO NPs as photo-catalysts. The nanocatalysts were recycled four times and still showed catalytic efficiency up to 95.5% for degradation of 4-CP in the specified 20 min.

Cationic dyes are widely used colorants in textile and other related industries. These dyes are highly toxic for marine life and make a major fraction of the industrial effluents. In this study, we report the synthesis of ester derivative of calix[4]arene (EDC) impregnated polymer inclusion membrane (PIM) and employed it for the transfer of cationic dyes between two aqueous phases. EDC forms inclusion complex with cationic dyes having 1:1 M ratio as revealed by the Job’s plot, the log/log plot, and the Benesi-Hildebrand methods while using methylene blue (MB) as a model cationic dye. EDC was used as carrier with cellulose triacetate (CTA) as a base polymer, and 2-nitrophenyl octyl ether (2-NPOE) as a plasticizer for the synthesis of EDC-PIM. Membranes were characterized by Fourier Transform Infrared spectroscopy (FT-IR), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET), and Barrett-Joyner-Halenda (BJH) analysis. The extraction performance of the synthesized PIM was optimized by varying different external parameters including pH of the donor and the acceptor phases, temperature, stirring speed, and concentration of EDC and dye while using MB as a model cationic dye. More than 90% extraction was achieved under optimized conditions which is 4.5-fold more than EDC-free-PIM. The extraction efficiency of the EDC-PIM remained similar after ten consecutive cycles that demonstrates its reusability potential in context of economical industrial applications. Finally, the synthesized EDC-PIM was used for selective extraction of other cationic dyes (basic red and nile blue) at the optimized conditions from the real industrial effluents. The extraction efficiency of the EDC-PIM was reproducible in all cases. The reusability and robustness of the EDC-PIM makes it an excellent candidate for retrieving cationic dyes from the industrial effluents.

This study presents selective and efficient extraction of a medicinally important compound rosmarinic acid (RA) via molecular imprinting. Molecularly imprinted polymer (MIP) and its respective non-imprinted polymer (NIP) were synthesized using methacrylamide (MAAm), itaconic acid (IA), and 4-vinyl-1,3-dioxolan-2-one (VD) as functional monomers, and trimethylolpropane trimethacrylate (TRIM) as a crosslinker via bulk polymerization, and characterized by SEM, BET, FT-IR, and TGA. The adsorption properties of MIP were evaluated by batch rebinding experiments, Scatchard analysis, LF-isotherm, and kinetic models. The MIP showed higher adsorption capacity towards RA compared to the corresponding NIP: 41.9 mg/g compared to only 9.6 mg/g. In addition, the synthesized RA-MIP displayed a good selectivity towards RA compared to its structural analogs in competitive recognition studies, confirming the development of RA specific imprinting sites. HPLC was utilized to determine the concentration of RA and analogous compounds in competitive recognition tests and in the real sample analysis. Finally, RA-MIP was successfully utilized for the selective enrichment of RA from the ethanolic extract of Salvia hypoleuca. The obtained results show that RA-MIP can be a promising alternative to conventional extraction methods for the selective extraction and enrichment of RA from complex plant matrices.

The work describes fabrication of structurally attractive CuO nanostructures using facile hydrothermal route. The nanostructures were synthesized by the application of suberic acid (SA),utilized both as an effective growth modifier and functionalizing agent. The dicarboxylic nature of SA allowed controlled growth of nanostructures and easy surface bound carbonyl functionalization. The SA-functionalized CuO nanostructures were observed to demonstrate high electro-catalytic potential for the oxidation of formoterol fumarate (FF) in aqueous medium. The high anodic current with low over potential observed for the CuO modified electrode enabled development of sensor system sensitive upto 0.01 μM. The enhanced electrochemical response was considered a synergetic outcome of the high surface area of CuO nanostructures and the facilitated interactions between the surface bound suberic acid and FF. Moreover, the excellent recoveries obtained for the FF from the broiler feed matrix and human serum samples further reflects the analytical robustness of the developed sensor.

The extensive release of heavy metals into the natural water bodies has become globally prevalent from past few decades. Heavy metal toxicity is becoming a serious threat to human and the environment. Due to their prolonged half-life, potential accumulation in different parts of body, and non-biodegradability, metal ions are being obvious entities that can cause several hazardous health risks. A number of methods have been developed for the detection of heavy/toxic metals based on sensors. Among the various new technologies, chemical and optical nano sensors are emerging technology to detect toxic heavy metals. Several nano sensors have been developed using nano materials, synthesized from green or chemical methods. The nano sensors are convenient to prepare and provide enhanced limit of detection, limit of quantification, and onsite detection. This review covers the recent work reported from 2013 to 2019 for the detection of heavy metals using sensors based on nano materials synthesized by different routes. Graphical abstract.

Analysis of nutrients to develop new or update food composition database is costly and time consuming. An alternate approach is to add the data on nutrients from existing literature using guidelines set by International Network of Food Data Systems (INFOODS). The currently available database for food composition in Pakistan is fairly old (2001) and thus, needs to be updated. In the present study mineral content of various foods from Pakistan was collected from existing literature and scrutinized against a set of criteria for inclusion in updated food composition database of Pakistan. Data for 37 food items with eight minerals (calcium, iron, zinc, phosphorus, magnesium, potassium, sodium and copper) fits under the criteria therefore is included in updated database for foods of Pakistan. Additionally, chromium, cobalt, cadmium, lead, nickel and manganese were also updated for 16 food items. Further, selected mineral content (iron, zinc, phosphorus and calcium) was compared with food composition Table of Pakistan (published in 2001). Comparison results showed that mineral content for most of the foods vary among two databases. The present study demonstrates feasibility of updating food composition databases thorough scientific reports on food products of a particular country.

Anthocyanins ACNs are water soluble plant pigments having a vital role in plant physiology and human health Grewia asiatica L genus Tiliaceae is a fruit producing shrub originating from south Asia Pakistan India East Cambodia cultivated mainly for its comestible fruit and well reported diverse medicinal uses The current study was the first attempt to characterize ACNs from G asiatica native to Pakistan Results revealed that maximum anthocyanin extraction yield micro g g was obtained with acidified methanol as compared to other investigated solvents water methanol ethanol and their binary mixture Total seven ACNs were identified including non acylated delphinidin O glucoside peonidin O glucoside pelargonidin O malonyl glucoside acylated cyanidin peonidin and pelargonidin O rdquo acetylglucoside and pyranoanthocyanin Malvidin O glucoside pyruvic acid Among them cyanidin O quot acetylglucoside was the major ACN comprising micro g g of total ACNs composition followed by peonidin O glucoside consisting of micro g g and pelargonidin O rdquo acetyl glucoside micro g g Moreover the study of ACNs stability at the temperature deg C testified the better temperature tolerance by ACNs under dark at temperature ranging deg C Hence the results revealed that G asiatica is a potent fruit rich in ACNs and can be used as food colorant and nutraceutical

Poly(2-hydroxyethyl methacrylate-glycidyl methacrylate) [p(HEMA-GMA)] cryogel discs were prepared under sub-zero temperatures. Gelatin was attached covalently on the p(HEMA-GMA) cryogel discs and reversible immobilization of horseradish peroxidase (HRP) was performed. The p(HEMA-GMA) cryogel discs were characterized by swelling tests, scanning electron microscopy, and surface area measurements. HRP immobilization capacity of p(HEMA-GMA)/gelatin cryogel discs was 24.8 mg/g. Removal of phenol from aqueous solutions was performed using HRP immobilized p(HEMA-GMA)/gelatin cryogel. It was observed that within 2 h of contact time, the percentage of phenol removal reaches up to 91% in the presence of H2O2.

This study concerns the investigation of dissipation, adsorption, and degradation of triazophos in different soils from Pakistan. These processes help in the disappearance of pesticide from the environment. Gas chromatography was used for dissipation and adsorption analysis while for degradation study mass spectrometer was used in addition of gas chromatography (GC-MS). The dissipation rate of triazophos in three different soils was 90% over 30 days with average half-life of 9.059 days. From dissipation study it was inferred that rate is variable in each soil due to climatic changes, soil nature and soil-pesticide interactions. Adsorption experiment has revealed that the adsorption of this pesticide to soil follows the pseudo first order kinetic model with rate constant value of 0.479/h and Freundlich isotherm with adsorption capacity of 1.832 mol/g. Degradation study has displayed two major metabolites, one is phosphorothioic acid, S-[2-[(1-cyano-1-methylethyl) amino]-2-oxoethyl] O,O-diethyl ester at ret...

A monolithic column with high-performance liquid chromatography coupled with an ultraviolet detector was investigated for the determination of ochratoxin A in poultry feed. A systematic study was performed using solid phase extraction with a C-18 cartridge for sample pretreatment with three solvent systems. Ethyl acetate:methanol:formic acid (95:5:0.5) was found to be the most suitable. Pretreated samples were injected separately into packed and monolithic columns. The effects of the mobile phases on the chromatographic figures of merits were evaluated. Better peak symmetry, improved separation, and more theoretical plates were observed using an acetonitrile:water:formic acid (99:99:2) mobile phase. The repeatability and accuracy of the method were statistically evaluated and found to be satisfactory with a limit of detection of 40 mu gL(-1). The use of a monolithic column in conjunction with sample pretreatment provided good results for the determination of ochratoxin A in poultry feed.

A novel rhodium biphenylic imidazole phenanthroline metal-organic complex (BIP-MC) has been synthesised and characterised as a stable supramolecule. The structure of compound was established on the basis ESI, 1H NMR and UV–vis spectroscopic data. The selectivity of BIP-MC as a new fluorescent chemosensor for various antibiotics has been explored. The supramolecular interaction of amoxicillin with BIP-MC enhanced the fluorescence activity of BIP-MC. A linear response of the sensor was observed in the measuring ranges of excitation 240–298 nm and emission 290–360 nm with detection limits of up to 10 μg/ml at an optimum pH 8.0. Based on the observations made here, a new quantitative method for the determination of this drug in synthetic samples without the use of separation of matrix is developed. It is also inferred that the possible fluorescence enhancement is due to the formation of exciplex between the BIP-MC and amoxicillin. These finding will thus help in pharmacokinetics studies of drugs. The sensor w...

The effect of different cooking methods (Raw, steaming, microwave cooking, baking, grilling, pan frying and deep frying) on proximate composition and fatty acid profile of Labeo calbasu fish species from Pakistan were analyzed to determine the nutritional qualities in terms of the long chain n-3 PUFA particularly EPA and DHA. In all cooking methods moisture content decrease and protein content increased as compare to raw sample. The moisture content of fish sample seemed to be inversely related to the total extractable lipid content. In steamed, microwave, baked, grilled and pan fried methods MUFA were the abundant fatty acids followed by SFA and PUFA. Deep fried fish sample had the opposite trend having highest PUFA as contrast to MUFA and SFA. Long chain n-3 PUFA were found higher in contrast to n-6 PUFA in all other cooking methods excluding deep frying. The results indicates that steamed and grilled cooking are the best cooking method for healthy eating as they contain more n-3 PUFA (EPA and DHA). Losses of n-3 content in pan fried and deep fried fish were higher than those of fish cooked by other methods.

This paper reports a rapid, simple, and sensitive method for determination of vitamin D3, vitamin E acetate, and vitamin K1 in plasma using atmospheric pressure chemical ionization –high performance liquid chromatography–mass spectrometry. Plasma samples were prepared using solid phase extraction. The separation of compounds was achieved using a C18 monolithic column and a mobile phase composed of methanol and 0.1% formic acid in gradient elution mode at a flow rate of 1.0 mL min−1. Analytes were ionized using atmospheric chemical ionization in positive mode. Mass spectra were recorded at m/z = 385.23, 473.47, and 451.41 for vitamin D3, vitamin E, and vitamin K1, respectively. Vitamin D2 was used as an internal standard and its mass spectra was recorded at 397.28 m/z. The method was validated using ICH guidelines. The system suitability responses were calculated for retention time, number of theoretical plates, capacity factor, resolution, and the selectivity factor. System validation was evaluated for pr...

Three different gas chromatographic detection techniques were applied for the determination of deoxynivalenol (DON) present in poultry feed samples. Extraction and cleanup procedures were kept the same for GC–FID, GC–ECD and GC–MS methods. Although all three GC methods provided good and comparable results, but more attention was focused on GC–FID due to its lower cost and easy availability in many laboratories. Therefore, a short 15 m DB-1 short column was introduced for the determination of DON in poultry feed to reduce the time of analysis and initial cost of column. An inter-laboratory study for GC–FID was performed in two laboratories using four naturally DONS-contaminated feed samples and one spiked with standard. The relative standard deviations for repeatability (RSDr) and relative standard deviations for reproducibility (RSDR) of naturally contaminated feed were in the range 5–23 and 11–24 %, respectively. The Horwitz Ratio (HORRAT) was less than 1.0 in each sample. From the spiking test, recovery, RSDr, RSDR and value of HORRAT were 93, 5, 11 and 0.6 %, respectively. For GC–FID method, limit of quantification was found to be 6 μg kg−1. Thus, GC–FID method using 15 m DB-1 capillary column is sensitive and validated analytical method for the determination of DON for poultry feed.

The present investigation reports the fabrication of thin film composite nanofiltration (TFC-NF) membranes using interfacial polymerization technique for desalination. Ethylene diamine (EDA) and terephthaloyl chloride (TPC) were employed as aqueous and organic phase monomers, respectively to develop polyamide thin layer on the surface of Celgard 2400. The prepared membranes were characterized through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The molecular weight cutoff of TFC-NF membranes was estimated to be below 342 Da using dextrose, sucrose and raffinose solutions. A low cost dead end NF Cell was designed and manufactured domestically to conduct permeation experiments. The effect of different reaction conditions including concentration of monomers, residence time in each monomer and curing temperature on the membrane performance (water flux and MgCl 2 rejection) was also studied. The water flux was augmented linearly at higher applied pressure while MgCl 2 rejection was remained constant. The obtained water flux and MgCl 2 rejection were measured 33 L/m 2 h and 90%, respectively at 7 bar applied pressure. Beside this, membrane stability was analyzed, which confirmed the excellent constancy of ethanol and n -hexane fluxes even after an extended period. Hagen–Poiseuille equation was applied to estimate the TFC-NF membrane pore size ∼0.45 nm.

The present study was undertaken to investigate the flavonoid profile in four species of ber (Ziziphus mauritiana Lamk.) fruit. The 12 flavonoids identified were quercetin 3-O-robinobioside, quercetin 3-O-rutinoside, quercetin 3'-O-galactoside, quercetin 3'-O-glucoside, quercetin 3'-O-rhamnoside, quercetin 3'-O-pentosylhexoside, quercetin 3-O-6'malonylglucoside, quercetin 3'-O-malonylglucoside, luteolin 7-O-6'malonylglucoside, luteolin 7-O-malonylglucoside, myricetin 3-O-galactoside, and naringenin tri glycoside. This is the first report on extraction of nine additional flavonoids from the ber fruits. In addition, we also compared the impact of three different base hydrolysis techniques namely ultrasonic assisted base hydrolysis (UABH), microwave assisted base hydrolysis (MWABH), and pressurised liquid assisted base hydrolysis (PLABH) for the quantification of total phenolic acids. Nine phenolic acids, protocatechuic acid, p-hydroxybenzoic acid, ferulic acid, chlorogenic acid, vanillic acid, caffeic acid, vanillin, ortho- and para-coumaric acids, were identified and quantified. The three major phenolic acids identified in all four ber species were p-coumaric acid, vanillin and ferulic acids. Higher amounts (p

A new extremely sensitive method for the determination of paracetamol by differential pulse voltammetry (DPV) using a micro-crystalline natural graphite–polystyrene composite film modified electrode (CFE) was developed. The experimental parameters, such as pH of Britton–Robinson buffer and potentials for regeneration of the electrode surface, were optimized. Under optimized conditions in Britton–Robinson buffer (pH 4.0), linear calibration curves were obtained in the range of 0.02–100 μmol l −1 of paracetamol. The limit of determination was 0.034 μmol l −1 which shows high sensitivity of the developed method. The method was applied for the determination of paracetamol in pharmaceutical formulations and in human urine model samples.

Aim Calligonum polygonoides Linn. (Polygonaceae) is commonly known as ‘Phog’ contains number of phytochemical constituents' viz. flavonoids, alkaloids, proteins, tannins, steroids, phenols, carbohydrates, terpenoids etc. The aim of the present study was to isolate and characterize steroids from the roots of C. polygonoides. Method Methanol extract of the roots of plant was subjected to column chromatography and eluted with solvent mixtures of increasing polarity, composed of chloroform, chloroform–ethyl acetate mixtures and ethyl acetate to isolate phytochemical constituents. The identities of these compounds were checked by solubility, preliminary phytochemical test, melting point determination and TLC study. Finally the structure was elucidated by different chromatographic and spectroscopic methods. Results On the basis of chemical and spectral evidence and upon comparison with the literature data, the isolated compounds were identified as campesterol (1), stigmasterol (2), (3β,5α,24S)-stigmastan-3-ol (3) and stigmast-4-en-3-one (4). Conclusion The steroids were isolated from the roots of C. polygonoides may serve as a potential source of useful drugs in the near future. The steroids were isolated first time from this plant extract.

A simple and rapid method was developed for the determination of erucic acid in rapeseed oil by single bounce attenuated total reflectance (SB-ATR) Fourier transform infrared (FTIR) spectroscopy. The various ratios prepared from the three different types of oils (rapeseed, canola, and sunflower) were run on gas chromatograph to identify amount of erucic acid. Therefore, a wide range of erucic acid (0.5‐ 53.0%) was obtained for the calibration. The partial least squares (PLS) calibration was used for predicting erucic acid using spectral region at 2983‐657/cm. The root mean square error of prediction (RMSEP), root mean square error of calibration (RMSEC), and root mean square error of cross-validation (RMSECV) were also determined to assess the accuracy of the method. The regression coefficient (R 2 ) was obtained 0.999 with least errors of RMSEC (0.12%), RMSECV (1.96%), and RMSEP (1.38%). The accuracy of the FTIR method was evaluated by analyzing canola and rapeseed oil samples by GC-MS and the results of both the techniques were found to be comparable. Practical applications: Generally, GC is used for determination of erucic acid in vegetable oils. But it needs the very laborious process of derivatization of fatty acids into their respective volatile methyl esters. Furthermore, lot of health hazardous chemicals and reagents are involved in the process of derivatization which are potential source for environmental pollution. Generally, FTIR spectroscopy has been recognized as a very simple, rapid, and cost effective technique. During the last decade, several researchers have used multivariate regression to build up calibration models based on FTIR data. The use of multivariate calibration methods is able to provide, estimates of the precision of the analysis, and yields important qualitative, quantitative, and analytical information. The objective of the present study was to develop a simple methodology for the quantitative analysis of low and high levels of erucic acid in canola and rapeseed oil, respectively by SB-ATR FTIR spectroscopy with PLSs regression.

The aim of study is to investigate the removal ability of some natural adsorbents for fluoride ion from aqueous solution. The batch dynamic adsorption method was carried out at neutral pH as the functions of contact time, adsorbent dose, adsorbate concentration, temperature and effect of co-anions, which are commonly present in water. The sorption kinetics and equilibrium adsorption isotherms of fluoride on natural adsorbing materials had been investigated at afore-mentioned optimized. Equilibrium adsorption isotherms, viz., Freundlich and Langmuir isotherms were investigated. Lagergren and Morris-Weber kinetic equations were employed to find the rate constants. The negative enthalpy ΔH = -46.54 KJ·mol-1 and Gibbs free energy calculated was ΔG288-333—(2.07785, 3.08966, 4.1064, 4.90716 and 5.38036 KJ·mol-1) respectively, envisage exothermic and spontaneous nature of sorption.

This work reports the application of banana peel as a novel bioadsorbent for in vitro removal of five mycotoxins (aflatoxins (AFB1, AFB2, AFG1, AFG2) and ochratoxin A). The effect of operational parameters including initial pH, adsorbent dose, contact time and temperature were studied in batch adsorption experiments. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHpzc) analysis were used to characterise the adsorbent material. Aflatoxins' adsorption equilibrium was achieved in 15 min, with highest adsorption at alkaline pH (6-8), while ochratoxin has not shown any significant adsorption due to surface charge repulsion. The experimental equilibrium data were tested by Langmuir, Freundlich and Hill isotherms. The Langmuir isotherm was found to be the best fitted model for aflatoxins, and the maximum monolayer coverage (Q0) was determined to be 8.4, 9.5, 0.4 and 1.1 ng mg(-1) for AFB1, AFB2, AFG1 and AFG2 respectively. Thermodynamic parameters including changes in free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) were determined for the four aflatoxins. Free energy change and enthalpy change demonstrated that the adsorption process was exothermic and spontaneous. Adsorption and desorption study at different pH further demonstrated that the sorption of toxins was strong enough to sustain pH changes that would be experienced in the gastrointestinal tract. This study suggests that biosorption of aflatoxins by dried banana peel may be an effective low-cost decontamination method for incorporation in animal feed diets.