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A xanthene-based probe, Xanth-NPr, is developed as a molecular system that exhibits sensitivity for the highly acidic environments with fluorescence turn-on behavior. Xanth-NPr is designed on the principle of photoinduced electron transfer (PET), which controls the fluorescence profile of the probe. The structure of Xanth-NPr contains the dipropylaniline group as a PET promoting unit. Xanth-NPr exhibited quenched fluorescence as long as it is present in neutral or moderately acidic conditions. However, in the highly acidic pH range, it displayed a strong red-colored fluorescence at 592 nm as the protonation of dipropylaniline moiety inhibits the PET process. A model probe Xanth-M without any PET promoting unit was also synthesized. The model probe along with theoretical calculations was employed to explain the role of the PET process in regulating the fluorescence behavior of Xanth-NPr. Xanth-NPr showed linear fluorescence response as a function of pH in the range of 1 to 4.1 with the pKa value of 2.72. Likewise, its fluorescence profile is not altered by the presence of biologically relevant cations.

In this work, effective mineralization of antibiotics, oxytetracycline (OTC) and ampicillin (AMP) using WO3/BiOCl photocatalyst stacked to graphene sand composite (GSC) and chitosan (CT) was investigated. Common sugar and river sand were used as precursor for the preparation of GSC. Modified hydrolysis method was used to prepare WO3/BiOCl photocatalyst with different weight percentage ratios of WO3. 60%WO3/BiOCl displayed highest photocatalytic efficiency for OTC and AMP removal. Furthermore, 60%WO3/BiOCl was immobilized onto GSC and CT to prepare 60%WO3/BiOCl/GSC and 60%WO3/BiOCl/CT nanocomposites. The prepared photocatalysts were characterized using FESEM, TEM, HRTEM, EDX, FTIR, XRD, FT-RAMAN, BET, photoluminescence and UV-Visible reflectance spectral analysis. Both 60%WO3/BiOCl/GSC and 60%WO3/BiOCl/CT displayed significant photocatalytic activity for OTC and AMP removal. The adsorption effect of OTC and AMP photodegradation was also evaluated. The adsorption of OTC and AMP was described by pseudo second order kinetics. Simultaneous adsorption and photocatalysis had synergetic effect on antibiotic degradation. Power law model was applied to understand the complex nature of mineralization process. 60%WO3/BiOCl/GSC and 60%WO3/BiOCl/CT exhibited significant recycle efficiency and easier recovery of photocatalyst for 10 catalytic cycles as compared to 60%WO3/BiOCl. Keywords: WO3/BiOCl, Antibiotics, Supported photocatalysis, Adsorption, Mineralization, Kinetics

The present study explored the bioactive properties (antioxidant, antihaemolytic and antibacterial properties) of hydrolysates produced from quinoa and amaranth protein isolates. Various hydrolysates were produced using different enzymes (Bromelain, Chymotrypsin and Protease) at various time of hydrolysis (2, 4, 6 h). The results revealed that highest ABTS and DPPH radical scavenging activities were demonstrated by 2 h and 4 h chymotrypsin generated quinoa and amaranth protein hydrolysates (QC-2 and AC-4), respectively. For antibacterial activity, the zone of inhibition increased with increase in time of hydrolysis when tested against Staphylococcus aureus and the highest inhibition was shown by 6 h bromelain generated amaranth protein hydrolysate (AB-6). Highest Salmonella typhimurium, Escherichia. coli and Enterobacter aerogenes inhibition was revealed by 4 h bromelain (QB-4), 4 h protease (QP-4) and 2 h protease (QP-2) generated quinoa protein hydrolysates, respectively, compared to other hydrolysates. Moreover, 6 h bromelain and protease generated amaranth and quinoa protein hydrolysates displayed highest antihaemolytic activity. The outcomes of this study suggested that antioxidant, antimicrobial and antihaemolytic properties were significantly improved upon hydrolysis of quinoa and amaranth proteins. Therefore, quinoa and amaranth protein hydrolysates could be considered as a promising source of bioactive peptides with potential health promoting benefits.

Camel milk proteins are an important substrate for bioactive peptides generation. This study investigates in-vitro antidiabetic effect (via inhibition of α-amylase (AA), α-glucosidase (AG) and dipeptidyl peptidase IV (DPP-IV)) of bovine (BC) and camel casein (CC) hydrolysates. Further, effect of simulated gastrointestinal digestion (SGID) on inhibitory potential of generated hydrolysates was also explored. Both BC and CC hydrolysates displayed potent inhibitory properties against AA (IC50 value- 0.58 & 0.59 mg/mL), AG (IC50 value- 1.04 & 0.59 mg/mL) and DPP-IV (IC50 value- 0.62 & 0.66 mg/mL), respectively. Among different peptides identified in BC and CC hydrolysates, it was observed that FLWPEYGAL was predicted to be most potent inhibitory peptide against AA. While LPTGWLM, MFE and GPAHCLL as most active inhibitor of AG and HLPGRG, QNVLPLH and PLMLP were predicted to be active against DPP-IV. Overall, BC and CC hydrolysates can be proposed to be used in different food formulations as functional antidiabetic agents.

Drinking water supplies are now proven to contain pharmaceutical residues, which are becoming a huge global problem. Pharmaceutical residues in water are also responsible for developing drug-resistant superbugs, which has emerged as a significant threat to global health. To tackle the above challenges, the present manuscript reports the development of a chitosan-attached gold nanoparticle conjugated graphene oxide architecture-based multifunctional three-dimensional (3D) porous membrane which has the capability for effective separation and label-free surface enhanced Raman spectroscopy (SERS) identification of pharmaceutical contaminants from environmental samples. In the reported design, due to the formation of 3D pores, a multifunctional membrane acted as channels for water passage. On the other hand, due to the presence of several adsorption mechanisms, the hybrid 3D graphene oxide (GO) surface can be used to remove contaminants from water. Due to the presence of a plasmonic nanoparticle-based “hot spo...

Even in 21st century, prostate cancer remains the second leading cause of cancer death for men. Since normal prostate gland contains the most Zn(II) and there are huge differences in Zn(II) content between the healthy and malignant prostate cancer cells, mobile zinc can be used as a biomarker for prostate cancer prediction. Current article reports the design of novel and highly efficient surface enhanced Raman spectroscopy (SERS) probe using p-(imidazole)azo) benzenethiol attached gold nanoparticle as a Raman reporter, which has the capability to identify prostate cancer cells based on Zn(II) sensing. A facile synthesis, characterization and evaluation as Zn(II) sensing Raman probe has been reported. Reported data indicate that after binding with Zn(II), Raman reporter attached gold nanoparticle forms assembly structure, which allows selective detection of Zn(II) even at 100 ppt concentration. Theoretical full-wave finite-difference time-domain (FDTD) simulation has been used to understand huge enhancement of SERS signal. Reported SERS probe is highly promising for in-vivo sensing of cancer, where near IR light can be easily used to avoid tissue auto-fluorescence and to enhance tissue penetration depth. Reported data show that SERS probe can distinguish metastatic cancer cells from normal prostate cells very easily with sensitivity as low as 5 cancer cells/mL. Designed SERS probe has the capability to be used as chemical toolkit for determining mobile Zn(II) concentrations in the biological sample.

Herein, we report synthesis of graphitic carbon sand composite (GSC) and bentonite (BT) supported superparamagnetic MnFe2O4 nanoparticles to obtain MnFe2O4/GSC and MnFe2O4/BT nanocomposites. Graphitic carbon sand composite (GSC) was prepared by graphitization of sugar over river sand. The particle size of MnFe2O4/GSC and MnFe2O4/BT was found to be 50 and 60 nm respectively. BET adsorption experiments confirmed mesoporous nature of prepared photocatalysts. Magnetic studies revealed superparamagnetic behavior of MnFe2O4/GSC and MnFe2O4/BT. The band gaps of MnFe2O4/GSC and MnFe2O4/BT were 2.38 and 2.42 eV respectively. Both MnFe2O4/GSC and MnFe2O4/BT exhibited significant photocatalytic activity for the mineralization of ampicillin (AMP) and oxytetracycline (OTC) antibiotics under solar light. Simultaneous adsorption and degradation process (A + P) resulted in higher photodegradation of OTC and AMP. The applicability of power law model indicated intricacies of mineralization process. MnFe2O4/GSC and MnFe2O4/BT displayed significant recycle efficiency and easier recovery of photocatalyst for 10 consecutive catalytic cycles.

In order to address the existing limitations of the commercially available fluorescent probe CMAC (7-amino-4-chloromethylcoumarin), a new series of highly fluorescent donor-acceptor 7-hydroxy-coumarin derivatives was prepared and these derivatives were used as vacuole specific fluorescent probes for live cell imaging of unicellular parasitic protozoa L. donovani promastigotes and yeast cells S. pombe and S. cerevisiae. The synthesized 7-hydroxy-coumarins exhibited interesting photophysical properties and have advantages such as excitation in the visible region, good water solubility, photo-stability, good quantum yield and low cytotoxicity.

In present study, heterojunctioned Bi2O3/BiOCl (BO/BOC) was synthesized via in situ chemical reduction and oxidation of BiOCl nanoplates. BiOCl was reduced to metallic Bi in KHB4 solution followed by oxidation in H2O2 solution to produce BO/BOC. The BO/BOC was supported over graphene sand composite and also on chitosan using wet impregnation method to report BO/BOC/GSC and BO/BOC/CT nanocomposite. The morphology and compositional characteristics of BO/BOC/GSC and BO/BOC/CT were investigated by FESEM, TEM, HRTEM, FTIR, XRD, EDX, RAMAN, BET and UV–visible diffuse reflectance spectral analysis. The photocatalytic activity of BO/BOC/GSC and BO/BOC/CT was performed for mineralization of ampicillin (AMP) and oxytetracycline (OTC) antibiotics under solar light. The adsorption process had significant effect on photodegradation of AMP and OTC. The adsorption of both OTC and AMP onto BO/BOC/GSC and BO/BOC/CT followed pseudo second order kinetics. Simultaneous adsorption and degradation process (A + P) resulted in higher degradation rate of investigated antibiotics. The applicability of power law model indicates the intricacies of mineralization process. During A + P process, OTC and AMP were mineralized to CO2·H2O, NO3− and SO42− ions. Both BO/BOC/GSC and BO/BOC/CT exhibited significant recycle efficiency.

In the preset manuscript, we intend to examine the type of solute-solvent interactions present in such system which is valuable to food/pharmaceutical sector. A systematic knowledge of the volumetric properties in conjunction with other thermodynamic properties provides useful information about water-solute interactions. We examine, therefore, surface tension, density, speed of sound and viscosity for binary system contains cationic surfactant cetyltrimetylammonium bromide (CTAB) in aqueous glycine solution (0.2, 0.3 and 0.4) mol/kg at four different temperatures ranging from (298.15 to 313.15) K. The surface tension result indicates the change in critical micelle concentration (CMC) values in the presence of additive. Various thermodynamic and adsorption parameters like surface excess, Γmax, minimum area at air-liquid interface, Amin etc. have been evaluated form surface tension data. The density and speed of sound measurements have been used to calculate the apparent molar volume and adiabatic compression which reveals the kind of interactions present pertaining to hydrophilic-hydrophillic and ion-hydrophillic interactions. In addition, hydrophobic hydration also plays a key role especially at higher surfactant concentration. Viscosity data further strengthen the concept of hydrophobic interactions present in the binary solution taken into consideration the relative viscosity and viscous relaxation time parameters. The effect of temperature and additive for all the calculated parameters has also been discussed in detail.

The study investigates photocatalytic activity of hydroxyapatite supported BiOCl (BiOCl/HA) in the presence of H2O2. BiOCl/HA was prepared by simple hydrolysis method. BiOCl/HA was characterized using scanning electron microscopy (SEM), tunneling electron microscopy (TEM), Xray diffraction (XRD), energy diffraction X-ray (EDX), Fourier transform infrared spectroscopy (FTIR) and UV-visible (UV-vis)analysis. SEM results confirmed the dispersion of BiOCl onto hydroxyapatite. BiOCl/HA exhibited irregular pleats-like structure having average size of 80 nm. The band gap of BiOCl/HA was found to be 3.42 eV. The solar light was used as radiation source during photocatalysis. Both H2O2 and BiOCl/HA had synergistic effect on oxytetracycline removal. The simultaneous adsorption and photocatalysis (A+P) was most efficient process for OTC removal. The photocatalytic degradation of oxytetracycline obeyed pseudo first order kinetics. The effect of process parameters catalyst loading, H2O2 concentration, pH and OTC concentration was investigated on photocatalysis. The oxidative removal occurred through hydroxyl radical formation. BiOCl exhibited significant recycle efficiency due to easier separation and stability in reaction solution. Solar/H2O2/BiOCl/HA displayed excellent photocatalytic property for degradation of OTC from aqueous solution. Copyright © 2016 VBRI Press.

A series of Torin2, a second-generation ATP-competitive inhibitor, analogues were biologically characterized to identify their potential for ATR and mTOR kinase inhibition. Compound SPK 98 was observed to inhibit ATR/mTOR kinase selectively over ATM kinase in HCT 116 cell line. In addition to that, SPK 98 on 30 min incubation with human, mice and rat liver microsomes showed improved properties with an increased half-life (a maximum T ½ of 157 min) and internal clearance in mouse as compared to Torin2. Further, SPK 98 was also noticed to indulge in inducing premature chromatin condensation as a result of ATR/mTOR kinase inhibition at 50 nM. In a nutshell, our work presents the identification and characterization of SPK 98, a small molecule inhibitor, which exhibits improved specific inhibition for ATR at a lower concentration than Torin2.

The study aimed to characterize and identify anti-diabetic and anti-hypertensive bioactive peptides generated upon enzymatic hydrolysis of quinoa protein isolates. Different quinoa protein hydrolysates (QPHs) were produced using food grade enzymes like Bromelain, chymotrypsin and Pronase E at a hydrolysis interval of 2 h up to 6 h. QPHs were characterized for their physicochemical properties using degree of hydrolysis, SDS-PAGE, and their anti-diabetic properties via inhibition of dipeptidyl peptidase-IV (DPP-IV) and α-glucosidase (AG), and anti-hypertensive property via inhibition of angiotensin converting enzyme (ACE) were explored. IC50 for DPP-IV, AG and ACE inhibitory activities of QPHs were in the range of 0.72–1.12, 1.00–1.86 and 0.18–0.31 mg/mL, respectively. The chymotrypsin derived 6 h hydrolysate (QC6) was sequenced for peptides identification and 136 peptides were identified among which 35 peptides were predicted as potential bio-active peptides (BAPs) based on their Peptide Ranker score. Results showed that identified peptides were predicted to possess high potential in inhibiting the DPP-IV, AG and ACE. In particular, QHPHGLGALCAAPPST was found to bind to the highest number of active hotspots of the target enzymes that are involved in their enzymatic activities. In conclusion, quinoa protein hydrolysates were identified as potential sources of BAPs with inhibitory properties towards key enzymes involved in the control of type 2 diabetes and hypertension.

Tumor heterogeneity is one of the biggest challenges in cancer treatment and diagnosis. A multicolor optical ruler is essential to address the heterogeneous tumor cell complexity. Driven by this need, the current article reports the design of a multicolor long range nanoscopic ruler for screening tumor heterogeneity by accurately identifying epithelial cells and cancer stem cells (CSCs) simultaneously. A nanoscopic surface energy transfer (NSET) ruler has been developed using blue fluorescence polymer dots (PDs) and red fluorescence gold cluster dots (GCDs) as multicolor fluorescence donor and plasmonic gold nanoparticle (GNP) acts as an excellent acceptor. Reported experimental results demonstrated that the multicolor nanoscopic ruler's working window is above 35 nm distances, which is more than three times farther than that of Förster resonance energy transfer (FRET) distance limit. Theoretical modeling using Förster dipole-dipole coupling and dipole to nanoparticle surface energy transfer have been used to discuss the possible mechanism for multicolor nanoscopic ruler's long-range capability. Using RNA aptamers that are specific for the target cancer cells, experimental data demonstrate that the nanoscopic ruler can be used for screening epithelial and CSCs simultaneously from a whole blood sample with a detection capability of 10 cells per mL. Experimental data show that the nanoscopic ruler can distinguish targeted cells from non-targeted cells.

Tumor metastasis is responsible for 1 in 4 deaths in the United States. Though it has been well-documented over past two decades that circulating tumor cells (CTCs) in blood can be used as a biomarker for metastatic cancer, there are enormous challenges in capturing and identifying CTCs with sufficient sensitivity and specificity. Because of the heterogeneous expression of CTC markers, it is now well understood that a single CTC marker is insufficient to capture all CTCs from the blood. Driven by the clear need, this study reports for the first time highly efficient capture and accurate identification of multiple types of CTCs from infected blood using aptamer-modified porous graphene oxide membranes. The results demonstrate that dye-modified S6, A9, and YJ-1 aptamers attached to 20–40 μm porous garphene oxide membranes are capable of capturing multiple types of tumor cells (SKBR3 breast cancer cells, LNCaP prostate cancer cells, and SW-948 colon cancer cells) selectively and simultaneously from infected blood. Our result shows that the capture efficiency of graphene oxide membranes is ∼95% for multiple types of tumor cells; for each tumor concentration, 10 cells are present per milliliter of blood sample. The selectivity of our assay for capturing targeted tumor cells has been demonstrated using membranes without an antibody. Blood infected with different cells also has been used to demonstrate the targeted tumor cell capturing ability of aptamer-conjugated membranes. Our data also demonstrate that accurate analysis of multiple types of captured CTCs can be performed using multicolor fluorescence imaging. Aptamer-conjugated membranes reported here have good potential for the early diagnosis of diseases that are currently being detected by means of cell capture technologies.

Circulating tumor cells (CTC) are highly heterogeneous in nature due to epithelial–mesenchymal transition (EMT), which is the major obstacle for CTC analysis via “liquid biopsy”. This article reports the development of a new class of multifunctional fluorescent–magnetic multicolor nanoprobes for targeted capturing and accurate identification of heterogeneous CTC. A facile design approach for the synthesis and characterization of bioconjugated multifunctonal nanoprobes that exhibit excellent magnetic properties and emit very bright and photostable multicolor fluorescence at red, green, and blue under 380 nm excitation is reported. Experimental data presented show that the multifunctional multicolor nanoprobes can be used for targeted capture and multicolor fluorescence mapping of heterogeneous CTC and can distinguish targeted CTC from nontargeted cells.