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Aisha Javed,1 Shah Rukh Abbas,1 Muhammad Uzair Hashmi,1 Noor Ul Ain Babar,2 Irshad Hussain2 1Department of Industrial Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Science and Technology, Islamabad, 44000, Pakistan; 2Department of Chemistry, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore, 54792, PakistanCorrespondence: Shah Rukh AbbasDepartment of Industrial Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, H-12, Islamabad, PakistanTel +92 3355449622; +92 51-9085-6125Email sabbas@asab.nust.edu.pkBackground: Mycobacterium tuberculosis’ rapid detection is still a formidable challenge to have control over the lethal disease. New diagnostic methods such as LED fluorescence microscopy, Genexpert, Interferon Gamma Release Assay (IGRA) are limited on efficacy spectrum owing to their high cost, time-intensive and laborious nature, in addition their low sensitivity hinders their robustness and portability. Electroanalytical methods are now being considered as an excellent alternative, being currently employed for efficient detection of the analytes with the potential of being portable. This report suggests label-free electrochemical detection of Mycobacterium tuberculosis (Mtb) via its marker, insertion sequence (IS6110).Methods: In this pursuit, graphene oxide-chitosan nanocomposite (GO-CHI), a biocompatible matrix, having a large electroactive area with an overall positively charged surface, is fabricated and characterized. The obtained GO-CHI nanocomposite is then immobilized on the ITO surface to form a positively functionalized electrochemical sensor for the detection of Mtb. DNA probe, specific for the IS6110, was electrostatically anchored on a positively charged electrode surface and the resistance of charge transfer was investigated for the sensitive and specific (complementary vs non-complementary) detection of Mtb by cyclic voltammetry and differential pulse voltammetry techniques.Results: The cyclic voltammetry was found to be diffusion controlled facilitating the absorption of analyte on the electrode surface. The label-free “genosensor” was found to detect a hybridization efficiency with a limit of detection of 3.4 pM, and correlation coefficient R2=0.99 when analysed over a range of concentrations of DNA from 7.86 pM to 94.3pM. The genosensor was also able to detect target DNA from raw sputum samples of clinical isolates without DNA purification.Conclusion: This electrochemical genosensor provides high sensitivity and specificity; thus offering a promising platform for clinical diagnosis of TB and other infectious diseases in general.Keywords: label-free detection, DNA genosensor, Mycobacterium detection, tuberculosis, graphene oxide nanocomposites, GO nanocomposites electrochemical sensing

Evaluation of terrestrial shale gas resource potential is a hot issue in unconventional oil and gas exploration. Organic-rich shales are widely developed in the Jurassic strata of Tarim Basin, but their shale gas potential has not been described well. In the study, the Lower-Middle Jurassic fine-grained sedimentary rocks (Kangsu and Yangye Formations) in northern Kashi Sag, northwestern Tarim Basin, were taken as the study object. The comprehensive studies include petrology, mineralogy, organic geochemistry, and physical properties, which were used to characterize the organic matter and reservoir characteristics. Results show that the Jurassic terrestrial shale in the northern Kashi Sag was mainly deposited in lakes, rivers, and deltas. The thickness of black lacustrine shale developed in the Early-Middle Jurassic in the study area is generally over 100 m. The total organic carbon (TOC) content is rich, averaging 2.77%. The vitrinite reflectance ( R o ) values indicate that the Lower Jurassic shale organic matter is in the early mature–mature stage, while the Middle Jurassic is in the mature stage. Besides, organic matter is primarily II and III in kerogen types. The whole shale contains a large number of clay minerals, especially illite. The average brittle minerals such as quartz and feldspar are 28.67%, and the average brittleness index is 38.63%. Nanoscale pores containing intergranular pores, dissolution pores, and organic pores, coupled with microcracks, are well developed in Jurassic shale. The sample’s average pore volume is 0.017 cm3/g, and the specific surface area is 9.36 m2/g. Mesoporous contribute the most to pore volume, while the number of microporous is the largest. Both of them provide most of the surface area for the shale. Combined with regional geologic settings, we propose that the Jurassic terrestrial shale has good-excellent shale gas exploration potential and development prospects.

Emulsion template-guided strategy has been used to produce porous architectures with exquisite structure, tailored morphology, and exclusive features for ubiquitous applications. Notwithstanding, the practical water remediation is often marred by their transport-limited behavior and fragility. To circumvent these conundrums, we prepared hierarchically porous poly(acrylic acid)-alumina nanocomposite beads by solidifying the droplets of emulsions jointly stabilized by the organic surfactants and alumina nanoparticles. By virtue of their positive charge, the alumina nanoparticles got entrapped within the poly(acrylic acid) scaffolds that excluded the risk of secondary contamination typically observed with conventional nanocomposites. Being amenable to surface modification, the carboxyl moieties of the beaded polymer were further exploited to covalently tether branched polyethylenimine throughout the exterior and interior surface of the porous matrix via a grafting-to approach. The macropores expedite an active fluid flow and easier adsorbate transport throughout the functionalized nanocomposites whose overall higher density of positive charge over a certain pH range electrostatically attracts and effectively adsorbs the negatively charged Cr(VI) complexes and anionic congo red ions/molecules from water. This proof-of-concept synthetic approach and postsynthetic modification offer an improved mechanical robustness to these macrosized multifunctional nanocomposite beads for their easier processing, thereby paving the way for the point-of-use water purification technology development.

In this study, the essential oil composition and antibacterial activity of the resin of Canarium strictum Roxb. was investigated. The oil was extracted by microwave-assisted extraction and analyzed...

Herein, we report a polysaccharide-based hydrogel isolated from psyllium husk (a well-known dietary fiber) and evaluated for its swelling properties in deionized water (DW) at different physiological pH values, i.e., 1.2, 6.8 and 7.4. Swelling of psyllium hydrogel (PSH) in DW under the influence of temperature and at different concentrations of NaCl and KCl solutions was also examined. A pH-dependent swelling pattern of PSH was observed following the order DW > pH 7.4 > pH 6.8 > pH 1.2. Stimuli-responsive swelling and deswelling (on–off switching) behavior of PSH was observed in DW and ethanol, DW and normal saline, at pH 7.4 and pH 1.2 environments, respectively. Similar swelling behavior and on–off switching attribute of PSH-containing tablets indicated the unaltered nature of PSH even after compression. Scanning electron micrographs of swollen and then freeze-dried PSH via transverse and longitudinal cross-sections revealed hollow channels with an average pore size of 6 ± 2 μm. Furthermore, PSH concentration-dependent sustained release of theophylline from tablet formulation was witnessed for >15 h following the non-Fickian diffusion mechanism. Subacute toxicity studies revealed the non-toxic nature of PSH. Therefore, dietary fiber-based material, i.e., PSH could be a valuable pharmaceutical excipient for intelligent and targeted drug delivery.

The use of water splitting modules is highly desired for the sustainable production of H2 as a future energy carrier. However, the sluggish kinetics and demand of high anodic potential are the bottlenecks for half-the cell oxygen evolution reaction (OER), which severely hamper the overall conversion efficiency. Although transition metal oxides based electrocatalysts have been envisioned as cost-effective and potential contenders for this quest, nevertheless, their low conductivity, instability, and limited number of active sites are among the common impediments that need to be addressed to eventually enhance their inherent catalytic potential for enhanced OER activity. Herein, the controlled assembly of transition metal oxides, that is, Cu@CuOx nanoclusters (NCs, ≈2 nm) and Co@CoOx beaded nanoclusters (BNCs, ≈2 nm), on thiol-functionalized graphene oxide (G-SH) nanosheets is reported to form novel and highly efficient electrocatalysts for OER. The thiol (-SH) functionality was incorporated by selective epoxidation on the surface of graphene oxide (GO) to achieve chemically exfoliated nanosheets to enhance its conductivity and trapping ability for metal oxides in nanoscale dimensions (≈2 nm). During the electrocatalytic reaction, overpotentials of 290 mV and 310 mV are required to achieve a current density of 10 mA cm-2 for BNCs and NCs, respectively, and the catalysts exhibit tremendous long-term stability (≈50 h) in purified alkaline medium (1 m KOH) with no dissolution in the electrolyte. Moreover, the smaller Tafel slopes (54 mV/dec for BNCs and 66 mV/dec for NCs), and a Faradic efficiency of approximately 96 % indicate not only the selectivity but also the tailored heterogeneous electrons transfer (HET) rate, which is required for fast electrode kinetics. It is anticipated that such ultrasmall metal oxide nanoclusters and their controlled assembly on a conducting surface (G-SH) may offer high electrochemical accessibility and a plethora of active sites owing to the drastic decrease in dimensions and thus can synergistically ameliorate the challenging OER process.

Pesticide contamination of drinking water is of high concern due to their hazardous effects on ecosystems. Several detection methods are available which are associated with many drawbacks, e.g. slow response time and laborious procedural techniques. This limits their practicability. Therefore, there is a dire need to develop quick, simpler but equally sensitive and practical methods for pesticide detection. Herein, we report a highly sensitive assay using fluorescent AuNCs for the detection of a pesticide i.e., 2-methyl-4-chlorophenoxyacetic acid (MCPA). For this purpose, three different fluorescent Au nanoclusters stabilized by histidine (His-AuNCs), lysozyme (Lys-AuNCs) and RNase (RNase-AuNCs) were systematically studied as optical probes for the detection of MCPA using a turn-on assay. The fluorescence of these AuNCs was initially quenched with Cu2+ ions followed by the quantitative recovery of their fluorescent signals in the presence of MCPA. The sensitivity and selectivity of these clusters for MCPA were in a linear dynamic range, i.e., 110–180 nM, 100–170 nM and 90–160 nM in case of His-AuNCs, Lys-AuNCs and RNase-AuNCs, respectively. Also, the aforesaid clusters were having a different limit of detection (LOD) by each type, i.e., highest by His-AuNCs (21.87), intermediate by Lys-AuNCs (12.97) and lowest by RNase-AuNCs (9.26 nM). Hence, the RNase-AuNCs are found to be the most sensitive, whereas His-AuNCs are least sensitive for the detection of MCPA. These findings offer a rapid, sensitive and selective assay for MCPA detection and have potential implications for the on-site, real-time monitoring of noxious pollutants.

Neisseria gonorrhoeae is among the most multidrug-resistant bacteria in circulation today, and new treatments are urgently needed. In this work, we demonstrate the ability of 5-mercapto-2-nitrobenzoic acid-coated silver nanoclusters (MNBA-AgNCs) to kill strains of Neisseria gonorrhoeae. Using an in vitro bactericidal assay, MNBA-AgNCs had been found to show significantly higher anti-gonococcal bioactivity than the antibiotics ceftriaxone and azithromycin and silver nitrate. These nanoclusters were effective against both planktonic bacteria and a gonococcal infection of human cell cultures in vitro. Treatment of human cells in vitro with MNBA-AgNCs did not induce significant release of lactate dehydrogenase, suggesting minimal cytotoxicity to eukaryotic cells. Our results suggest that MNBA-AgNCs hold great potential for topical treatment of localized gonorrhoeae.

It is necessary to study the possible interactions among various chemical surfaces and analytes before applying them to biological systems. We report the synthesis of carbon nanotubes-iron oxide (SPIONs-CNT) nanocomposite material by using lecithin stabilized superparamagnetic iron oxide nanoparticles (SPIONs) obtained by facile hydrothermal technique. Various characterizations of the obtained nanocomposite were carried out and electrochemical studies were performed further to study the interaction capabilities of the nanocomposite with anti-TB drug Rifampicin. Obtained results by cyclic voltammetric studies of SPIONs-CNT nanocomposite with limit of detection (LOD) of 1.178 μM showed the enhanced electrochemical sensitivity and selectivity of anti-tuberculosis (anti-TB) drug Rifampicin (RIF).

Heliotropium crispum-mediated assembly of silver nanoparticles exhibit profound antibacterial and anti-biofilm effects against multiple drug-resistant bacteria, but its stability and biocompatibility remain a hurdle in commercialization. Herein, we adopted a surface chemistry-based steric repulsion approach to investigate the colloidal stability of H. crispum silver nanoparticles (HC-AgNPs) and determine its application as a commercial antibacterial formulation. Two primary silver nanoparticles (AgNPs) were synthesized, i.e., HC-AgNPs and citrate-HC-AgNPs initially, which were then modulated to assemble various derivatives of AgNPs using polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) as stabilizing agents. Various parameters were assessed to investigate the morphology, colloidal physio-chemistry, and surface capping using various analytical techniques, such as UV–Vis spectrophotometer, zeta–dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM, and transmission electron microscopy (TEM). Selective AgNPs were then screened on the basis of stability for up to 8 months, heat resistance at 100 °C, and bioactivity via MTT assay using HEP-2, MCF-7, and HCEC cell lines. The UV–Vis and electron microscope results revealed that HC-AgNPs confer near-spherical and slight triangular-shaped morphology and the size of all synthesized AgNPs is in the range of 400–450 nm. All AgNPs synthesized from HC-source have characteristic FTIR peaks recorded near 2931 cm−1, 1996 cm−1, and 825 cm−1. This study highlights promising evidence for the commercial application of HC-AgNPs as an antimicrobial agent. Additionally, it provides a methodology for modulating the surface capping of biological nanoparticles and assesses its corresponding effect on the stability.

Functionalized hypercrosslinked polymers have presented potential applications in various fields and are highly potent in bio-medical applications. Irrespective of random morphology, hypercrosslinked polymers with a spherical and hollow capsular shape are worthy of fabrication and functionalization. Based on the appealing performance of polymeric capsules, herein we report the synthesis of folate-functionalized biocompatible hollow capsules that have a reasonable potential for the delivery of anticancer drugs specifically to the cancer cells. The pyrene units are incorporated into these capsules to further enhance their scope for imaging applications. To improve the targeting efficiency, the folic acid was conjugated to the surface of hollow microporous organic capsules (HMOCs-FA) via a facile strategy using SiO2 nanoparticles as templates and the covalent attachment of FA on the surface of capsules. These microporous organic capsules exhibit a high surface area of up to 700 m2 g−1 and a maximum encapsulation drug efficiency of up to 86%. Moreover, the HMOCs-FA are highly biocompatible and are internalized by MCF-7 and MDA-MB-231 cell lines via folate receptor mediated endocytosis.

Artemisia vulgaris seeds extrude hydrogel (AVH), which shows extraordinary swelling in water, at pH 6.8, and 7.4, which follows second-order kinetics. AVH exhibits reversible swelling/deswelling in ethanol and normal saline as well at pH 7.4 and pH 1.2. Therefore, AVH shows stimuli-responsiveness in different physiological conditions, solvents, and electrolytes. The superporous nature of AVH in swollen/freeze-dried sculpture is exposed in their SEM micrographs. AVH-based aceclofenac tablet formulations offer sustained-release under simulated conditions of the gastrointestinal tract (GIT) in terms of pH and transit time. Pharmacokinetic studies also show the delay and prolonged plasma concentration with tmax of 8 h, therefore, such formulations can be used to enhance the bioavailability of aceclofenac. The swelling behavior of the AVH tablet is also assessed using MRI. The in vivo fate of the AVH tablet is monitored by X-ray during the transit through the GIT. Acute toxicity studies of AVH indicate the absence of any toxicity which reveals the safety profile of AVH. Therefore, AVH can be used for oral, topical and ophthalmic drug delivery systems. These results establish the potential of AVH as a stimuli sensitive, pH-dependent, and sustained-release biomaterial for targeted drug delivery.

Metal nanoclusters (NCs, size ≤2 nm) are emerging materials in catalysis owing to their unique catalytic and electronic properties such as high surface/volume ratio, high redox potential, plethora of surface active sites, and dynamic behavior on a suitable support during catalysis. Herein, in situ growth of ultrasmall and robust Co@β-Co(OH)2 NCs (≈2 nm) hosted in a honeycomb-like 3D N-enriched carbon network was developed for water-oxidation catalysis with extremely small onset potential (1.44 V). Overpotentials of 220 and 270 mV were required to achieve a current density of 10 mA cm-2 and 100 mA cm-2 , respectively, in alkaline medium (1 m KOH). More promisingly, at η10 =240 mV, the prolonged oxygen evolution process (>130 h) with faradaic efficiency >95 % at a reaction rate of 22 s-1 at 1.46 V further substantiated the key role of the ultrasmall supported NCs, which outperformed the benchmark electrocatalysts (RuO2 /IrO2 ) and NCs reported so far. It is anticipated that the high redox potential of NCs with regeneratable active sites and their concerted synergistic effects with the N-enriched porous/flexible carbon network are inherently worth considering to enhance the mass/charge transport owing to the nanoscale interfacial collaboration across the electrode/electrolyte boundary, thereby efficiently energizing the sluggish/challenging oxygen evolution process.

Tainting of waterbodies with noxious industrial waste is the gravest environmental concern of the day that continues to wreak inevitable havoc on human health. To cleanup these hard-to-remove life-threatening water contaminants, we have prepared hierarchically porous poly(acrylic acid) beads by emulsion templating. These emulsion-templated macroporous polymer beads not only mediate the synthesis of Fe3O4 nanoparticles inside their porous network using a coprecipitation approach but, in turn, create diverse anchoring sites to immobilize an additional poly(acrylic acid) active layer onto the nanocomposite beads. These post-synthetically modified nanocomposite beads with macropores and abundant acrylic acid moieties offer the ready mass transfer and fair advantage of relatively higher overall negative charge to efficiently adsorb lead [Pb(II)] and crystal violet with impressive performance-even superior to many of the materials explored in this regard so far. Furthermore, the strong entanglement of nanoparticles in the porous polymeric scaffolds tackles the curb of trade-off between all-round effective remediation and secondary pollution and the millimeter size eases their processing and recovery during the adsorption tests, thereby making these materials practically worthwhile.

Mesoporous silica (MPS) and MPS-Fe composite was prepared via sol–gel technique and characterized by BET, FTIR, XRD, SEM and pZc. The MPS and MPS-Fe adsorption efficiencies were evaluated for a cationic dye Turquoise-blue X-GB. The MPS-Fe composite showed pore size and BET values of 9.52 nm and 309 m2/g, respectively. XRD and SEM analysis revealed the amorphous nature and uniform distribution of spherical partciles with average particle size of 50 nm of MPS-Fe composite. The points of zero (pZc) charge found to be 2.3 and 6.3 for MPS and MPS-Fe, respectively. The MPS and MPS-Fe showed promising efficiency for the adsorption of Turquoise-blue X-GB as a function of medium pH, contact time, dye initial concentration and temperature. Among, Freundlich, Langmuir, Harkins–Jura, Temkin, Doubinin–Radushkevich isotherms, the Turquoise-blue X-GB followed Langmuir isothermal model with adsorption capacities of 83.34 mg/g and 74.07 mg/g for MPS and MPS-Fe composite, respectively. Among kinetics models, pseudo second order kinetic model fitted to the dye adsorption with R2 values of 0.998 and 0.988 for MPS and MPS-Fe composite, respectively. The negative values of enthalpy (ΔH) and free energy (ΔG) revealed exothermic and spontaneous adsorption of dye at room temperature. Results revealed that MPS and MPS-Fe composite have promising potential for Turquoise-blue X-GB dye adsorption and could possibly be extended for the adsorption of dyes from textile effluents.

Barley is the most imperative cereal crop and ranks on 4th around the world after wheat, corn and rice. The aim of present research work to determine the Nutritional, phytochemical and Mineral profile and mycotoxin load, 05 barley samples were collected from Hyderabad Division. The nutritional, phytochemical and mineral profile indicate that the barley contain significant level of carbohydrates, protein, Alkaloids, Flavonoids, tannins, saponins and antioxidants, the trace and mineral profile of the barley samples indicates the nutrient potential, in the present study the significant quantity of metals (Co, Ni, K, N, Mg, Zn, Ca and Fe) was observed in all barley samples of the Hyderabad division. The mycotoxins load (total aflatoxin) on the barley samples were estimated in ng/g , the highest load 47 ng/g of total aflatoxin was observed in the TA samples and level, the lowest level of the total aflatoxin was observed in the samples of MPK. Therefore it was concluded on presents facts that barley is nutrient rich cereals but due to the presence of mycotoxin the quality of nutrient present in barley has lost and can leaving the severe health effect on human when consumed aflatoxin contaminated barley chronically.

PurposeThis study aimed to present fabrication of novel poly(lactic acid) (PLA) mediated chitosan nanoparticles (CNPs) and their impregnation on cotton fabric for enhanced antibacterial and physical properties.Design/methodology/approachThe PLA-CNPs were characterized using scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared (FTIR) spectroscopy and zeta size analysis. The prepared PLA-CNPs were impregnated on cotton fabric via pad-dry-cure method. The finished cotton fabric was then characterized for its antibacterial activity, functional and other physical textile properties.FindingsThe spectral and optical properties demonstrate that the NPs expressed spherical morphologies with an average particle diameter of 88.02 nm. The antibacterial activity of treated fabrics ranged between 75 and 90 per cent depending on the concentration of PLA-CNPs.Practical implicationsBecause of enhanced awareness and desire for ecofriendly products, the use of sustainable and functional textiles is increasing day by day. For the said purpose, industries are using different chemical treatments to achieve desired end functionality. Currently, different synthetic antibacterial agents are in practice, but they lack sustainable approach to save the environment. In this study, the researchers have developed PLA mediated CNPs for sustainable antibacterial and physical properties of treated cotton fabric.Originality/valueTo the best of the authors’ knowledge, this is first attempt to fabricate PLA-incorporated CNPs for application on cotton fabric followed by a detailed characterization.

Significant efforts have been devoted to develop efficient visible-light-driven photocatalysts for the conversion of CO2 to chemical fuels. The photocatalytic efficiency for this transformation largely depends on CO2 adsorption and diffusion. However, the CO2 adsorption on the surface of photocatalysts is generally low due to their low specific surface area and the lack of matched pores. Here we report a well-defined porous hypercrosslinked polymer-TiO2-graphene composite structure with relatively high surface area i.e., 988 m2 g−1 and CO2 uptake capacity i.e., 12.87 wt%. This composite shows high photocatalytic performance especially for CH4 production, i.e., 27.62 μmol g−1 h−1, under mild reaction conditions without the use of sacrificial reagents or precious metal co-catalysts. The enhanced CO2 reactivity can be ascribed to their improved CO2 adsorption and diffusion, visible-light absorption, and photo-generated charge separation efficiency. This strategy provides new insights into the combination of microporous organic polymers with photocatalysts for solar-to-fuel conversion.

Copper nanoclusters (CuNCs) exhibit susceptibility to oxidation in the subnanometer size range. In this work, a facile and green protocol is reported for the successful synthesis of water soluble CuNCs, with poly(vinylpyrrolidone) as a template and ascorbic acid as a mild reducing agent. The as-prepared CuNCs exhibit a green fluorescence and high quantum yield (QY = 44.67%) in water, which is the highest among the reported water soluble CuNCs. The origin of their highly luminescent nature was also investigated. In addition, the obtained CuNCs show good tolerability to high ionic strength, superior antioxidation properties, good photostability, time-stability, a large Stokes shift and ultralow cytotoxicity, laying the foundation for living cell imaging in THP-1 macrophages. A bright green fluorescence can be observed from the cells, indicating the potential practicality of CuNCs as a fluorescence marker in bioapplications. Interestingly, the as-prepared CuNCs exhibit a good selective fluorescence quenching response towards trinitrophenol over other nitro compounds. Furthermore, CuNCs were employed for sensing trinitrophenol based on the inner filter effect. A good linear relationship was obtained in the low concentration range of trinitrophenol, with a limit of detection of 3.91 × 10-7 M in aqueous medium. This result suggests the potential application of CuNCs as a probe in sensing and monitoring toxic trinitrophenol in the field of environmental security.

Ocimum basilicum L. seed mucilage (OBM) was separated mechanically and esterified to form OBM succinate (OBMS) and sodium salt of OBMS (Na-OBMS). These products were then exploited for Cd(II) removal from spiked high hardness ground water (HGW) and distilled water (DW) solution. Na-OBMS was characterized by FT-IR (Fourier-transform infrared spectroscopy), SEM-EDS (scanning electron microscopy-energy dispersive spectroscopy), zero-point charge pH and solid-state CP/MAS 13C NMR (nuclear magnetic resonance spectroscopy). Na-OBMS was found to be a good sorbent for Cd(II) removal from DW and HGW. Effects of pH (1–7), temperature (290–343 K), interaction time (5–120 min) and sorbent dose (10–60 mg) on sorption capacity of the sorbent Na-OBMS were investigated. Negative values of different thermodynamic parameters (ΔG°, ΔS°, and ΔH°) indicated the exothermic and spontaneous nature of sorption. Different isothermal and kinetic models were applied on sorption data. Langmuir isothermal model and pseudo second order kinetic model provided best fit to the experimental sorption data. Maximum sorption capacity of Na-OBMS for Cd(II) uptake as determined by Langmuir isothermal model was found as 443.06 and 405.63 mg g−1 for DW and HGW, respectively. The sorbent was recovered simply by treating with brine and utilized again for sorption. A negligible decrease (9.5 and 11.4% for DW and HGW, respectively) was found in the efficacy of sorbent after 5 cycles of recovery.

The development of metal nanoparticles supported in porous materials is important for the development of highly efficient heterogeneous catalysis. Because of the quantum-size effect, the size of th...

The demand of high anodic potential for oxygen evolution reaction (OER) because of its sluggish kinetics limits the overall efficiency and practical applications of electrochemical water splitting ...

Bacterial multidrug resistance (MDR) is a serious healthcare issue caused by the long-term subtherapeutic clinical treatment of infectious diseases. Nanoscale engineering of metal nanoparticles has great potential to address this issue by tuning the nano–bio interface to target bacteria. Herein, we report the use of branched polyethylenimine-functionalized silver nanoclusters (bPEI–Ag NCs) to selectively kill MDR pathogenic bacteria by combining the antimicrobial activity of silver with the selective toxicity of bPEI toward bacteria. The minimum inhibitory concentration of bPEI–Ag NCs was determined against 12 uropathogenic MDR strains and found to be 10- to 15-fold lower than that of PEI and 2- to 3-fold lower than that of AgNO3 alone. Cell viability and hemolysis assays demonstrated the biocompatibility of bPEI–Ag NCs with human fibroblasts and red blood cells, with selective toxicity against MDR bacteria.

International audience; Aim: To fabricate and evaluate curcumin-loaded transfersomes (Cur-TF) for the targeted delivery and enhanced therapeutic efficacy of curcumin for the treatment of rheumatoid arthritis (RA). Methods: Modified thin-film hydration method was used to prepare Cur-TF which were then embedded into carbopol-934 gel. They were further evaluated through in vitro techniques and in an in vivo arthritis model. Results: Cur-TF had optimal particle size, spherical morphology, high encapsulation efficiency and sustained drug release profiles. The Cur-TF gel had better in vitro skin penetration than plain curcumin. In vivo findings demonstrated improved clinical, histological and x-ray scores and reduced pro-inflammatory cytokines through NF-κβ inhibition. Conclusion: Cur-TF gel delivered curcumin to the arthritic dermal tissue through a topical route and demonstrated promising therapeutic efficacy by significantly alleviating complete Freud's adjuvant (CFA)-induced arthritis.

Multidrug resistance (MDR) has been a potentiator for the exploration of antibiotics. Nano drug delivery systems have opened new avenues to overcome this challenge. Although antibacterial nanocarriers are extensively realized, their effect on the bacteria residing inside the tissues and their toxicity is rarely explored. This study investigated the effects of flavonoid coated gold nanoparticles (FAuNPs) on the colonization of Enterococcus faecalis in the mouse liver and kidneys. Flavonoids were extracted from the leaves of Berberis lycium Royle and used to stabilize gold following a green synthesis approach. FAuNPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (STEM), X-ray powder diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). FAuNPs showed significantly higher reduction in bacterial counts in in-vitro and in-vivo in mice organs as compared to the free flavonoids owing to their biocompatibility and effectiveness.

A facile, green synthesis of selenium doped zinc oxide nano-antibiotic (Se-ZnO-NAB) using the Curcuma longa extract is reported to combat the increased emergence of methicillin-resistant Staphylococcus aureus (MRSA). The developed Se-ZnO-NAB were characterized for their physicochemical parameters and extensively evaluated for their toxicological potential in an animal model. The prepared Se-ZnO-NABs were characterized via Fourier transformed infrared spectroscopy to get functional insight into their surface chemistry, scanning electron microscopy revealing the polyhedral morphology with a size range of 36 ± 16 nm, having -28.9 ± 6.42 mV zeta potential, and inductively coupled plasma optical emission spectrometry confirming the amount of Se and Zn to be 14.43 and 71.70 mg L-1 respectively. Moreover, the antibacterial activity against MRSA showed significantly low minimum inhibitory concentration at 6.2 μg mL-1 when compared against antibiotics. Also, total protein content and reactive oxygen species production in MRSA, under the stressed environment of Se-ZnO-NAB, significantly (p < 0.05) decreased compared to the negative control. Moreover, the results of acute oral toxicity in rats showed moderate variations in blood biochemistry and histopathology of vital organs. The teratogenicity and fetal evaluations also revealed some signs of toxicity along with changes in biochemical parameters. The overall outcomes suggest that Se-ZnO-NAB can be of significant importance for combating multi-drug resistance but must be used with extreme caution, particularly in pregnancy, as moderate toxicity was observed at a toxic dose of 2000 mg kg-1.

This study aims to introduce a simple, sensitive, and cost-effective method for the simultaneous determination of acetamiprid and its main metabolite 6-chloronicotinic acid in environmental samples by using a nonsuppressed ion chromatography hyphenated with an online postcolumn photoinduced fluorescence detection system. The fluorescence detector wavelengths λex /λem = 257/382 nm was set for up to 6.0 min for acetamiprid, while λex /λem = 231/370 nm programmed for 6-chloronicotinic acid for the rest of the analysis time. Both samples were treated by applying miniaturized quick, easy, cheap, effective, rugged, and safe method before the separation of analytes on an IonPac® AS11-HC column by pumping 40 mM NaOH having minuscule content of acetonitrile (5%, v/v) as an eluent. Both intrinsically nonfluorescent analytes were turned-on by online postcolumn photoinduced derivatization, avoiding the need for complex chemical derivatization or addition of a postcolumn extra pump. The developed method was appraised for the analysis of environmental samples, exhibiting excellent linearity (0.050-10 μg/mL) with a correlation coefficient greater than 0.9993 for both analytes. Whereas, obtained limit of detection (0.025-0.0072 μg/mL), recoveries (98.02-116.00%), and inter- and intraday precision (≤3.02 %) were satisfactory for both compounds in environmental samples.

We report the synthesis, characterization and evaluation of lecithin-drug hybrid nanocarriers (NCs) with enhanced oral bioavailability and anti-parasitic potential for poorly water-soluble drugs. Amphotericin B (AmB), a poor water-soluble drug with poor membrane penetrating ability, was selected as a model drug to demonstrate the potential of the lecithin-drug hybrid NCs. Lec-AmB NCs were prepared by the self-assembly of lecithin into nanoparticles (NPs) at a critical micellar concentration of 4 mg ml−1 and into liposomes at a critical liposomal concentration of 53 mg ml−1 in aqueous systems. The Lec-AmB NPs (200–300 nm) were further coated with polyethylene glycol (MW 600) and Tween 20, whereas the liposomes (70–90 nm) were used as such for this study. The Lec-AmB NCs were evaluated for their ability to boost in vivo oral pharmacokinetic parameters in rabbits and in vitro anti-leishmanial activity against the promastigotes of Leishmania tropica. A reciprocal relationship was observed between the size and drug encapsulation efficiency of the NPs, but no such relationship was observed in the case of the liposomes. More importantly, the oral bioavailability and anti-leishmanial activity of Lec-AmB NPs was enhanced up to 21- and 6.3-fold, and 21- and 2-fold, respectively, in the case of the liposomes. The improvement in the bioavailability and anti-leishmanial activity is very significant compared to the deoxycholate complex of AmB (water soluble, injectable market product: Anfotericina FADA®), and this study, thus shows the promising potential of easy-to-prepare NCs with improved therapeutic efficiency using phosphocholine-based biocompatible surfactants.

Present research demonstrated the crosslinking of Cydonia oblonga seeds hydrogel using citric acid (CA) and evaluated its stimuli-responsive swelling properties at different biomimetic pH, swelling/deswelling behavior against different fluids and sustained release potential in orally administered tablet formulation. Cross-linked C. oblonga hydrogel (CL-COH) was synthesized using four concentrations of CA, i.e., 1.25%, 2.5%, 5% and 10% and characterized through Fourier transform infrared (FTIR) spectroscopic analysis. CL-COH exhibited high swelling capacity at pH 6.8, 7.4 and in deionized water whereas, insignificant swelling was observed at pH 1.2. Swelling/deswelling response of CL-COH (2.5% CA) at pH 7.4 and 1.2, in deionized water and ethanol, and deionized water and normal saline were remarkable and reproducible results were obtained even after four cycles. Scanning electron microscopy (SEM) images of CL-COH indicated evenly distributed web of interconnected macro-pores. CL-COH was used as a pH-sensitive sustained release material for the preparation of oral tablet formulation of levosulpiride. In vitro drug release study revealed that the drug release followed zero-order kinetics and drug release mechanism was found as a super case II transport. Non-thrombogenic and non-hemolytic potential of CL-COH was ascertained through haemocompatibility studies. Therefore, CL-COH can be a versatile stimuli-responsive and biocompatible polysaccharide-based material for zero-order sustained release of drugs.

Microneedle patch is a prominent strategy with minimal invasion and painless application to improve skin penetration of drug molecules. Herein, we report microneedle patch (MNP) as an alternative to the oral route for the systemic delivery of tacrolimus (TM), an immunosuppressant drug. Thiolated chitosan (TCS) based microneedle patch was fabricated and characterized in vitro and in vivo for its mechanical strength, skin penetration, drug release, and skin irritation. The MNP having 225 needles with 575 μm showed good mechanical properties in terms of tensile strength and percentage elongation. The skin penetration showed 84% penetration with no breakage. Histology of the mice skin after insertion showed the penetration of needles into the dermis. In vitro release and ex vivo permeation studies through Franz diffusion cell showed the sustained release (82.5%) of TM from the MNP with significantly higher (p

Cadmium(II) complexes of thioureas, [Cd(Tu)(SO4)(H2O)2]n (1), [Cd(Dmtu)(SO4)(H2O)2]n (2) and [Cd(Mpy)2(SO4)]n (3) (Tu = thiourea, Dmtu = N,N′-dimethylthiourea and Mpy = 2-mercaptopyridine) were prepared and characterized by IR and NMR spectroscopy, and thermal analysis. While the solid state structure of 1 is known in the literature, the structures of 2 and 3 were determined by single crystal X-ray crystallography. Complexes 2 and 3 exist in the form of one-dimensional polymers. In 2, each cadmium atom is octahedrally coordinated by two doubly bridging Dmtu ligands, two sulfate ions and two water molecules. In 3, the octahedral coordination at the cadmium atom is attained by four bridging Mpy ligands and two sulfate ions. The results of the thermal analyses of 1 and 2 indicate a good correlation between the calculated and found weight loss values. The IR spectra of 1–3 were simulated and interpreted by means of periodic DFT calculations of their modelled polymeric solid state structures. The IR and NMR spectroscopic data are consistent with sulfur coordination of the thiones and oxygen coordination of the bridging sulfato group to the cadmium(II) ions. The antimicrobial activities of the complexes were evaluated by their minimum inhibitory concentrations and the results showed that the complexes exhibit moderate activities against gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). The activities against molds (Aspergillus niger and Penicillium citrinum) were poor, while the complexes were almost ineffective against yeasts (Candida albicans and Saccharomyces cerevisiae).

A new copper(II) complex containing cis-1,2-diaminocyclohexane (Dach) and azide as ligands, [Cu(Dach)2(N3)]Cl · 3H2O (1), was prepared and characterized by IR spectroscopy, thermal analysis and X-ray crystallography. The structure of 1 consists of a complex cation, [Cu(Dach)2(N3)]+, a chloride counter-ion and three water molecules. The coordination environment of the copper(II) atom in 1 is distorted square pyramidal attained by four nitrogen atoms of cis-1,2-diaminocyclohexane molecules and an azide ion. Thermogravimetric and differential scanning calorimetric analyses validated the molecular formula of complex 1.

We propose a facile, cost-effective and commercially viable method to prepare durable superhydrophobic surfaces using a bio-waste material. The naturally available nanostructured sawdust particles were combined with polychlroprene adhesive, carbon soot and silicon polymer to formulate superhydrophobic coatings. Saw dust particles were bonded on the substrate using polychloroprene adhesive, which was followed by depositing silicone by dip-coating to produce a superhydrophobic surface. To further improve the mechanical and superhdyrophobic properties, a thin layer of carbon soot was deposited and stabilized by second layer of silicone. Electron microscopy, spectroscopy and goniometry were employed for microstructural analysis, chemical nature and the contact angle measurements of the coatings. After quantifying the excellent response against mechanical abrasion, the superhydrophobic coating was employed on a mesh to demonstrate its application for oil/water separation. It was observed that the coated mesh successfully separated both light and heavy oils from oil/water mixtures with high separation efficiency and therefore has the potential for large-scale separation of oil/water mixtures.

Nano/microscale TiO2 materials and their composites have reached the pinnacle of their photocatalytic performances to destroy persistent organic pollutants and waterborne microorganisms, but their practical applications are limited by the drawbacks associated with their stability, leaching, processing and separation. To overcome these shortcomings, we have prepared hierarchically porous nanostructured TiO2 macrobeads via an exotemplating or nanocasting strategy by infiltrating the TiO2 sol into the emulsion-templated porous polyacrylamide scaffold followed by its gelation, drying and calcination. The nanoscale TiO2 building units tailor the shape of the porous polymeric network after calcination thereby retaining the macroscale morphology of polymer beads after template removal. A novel combination of the hierarchical macroporosity, orderly crystalline anatase nature, nanoscale feature and good surface area revealed by the relevant characterization tools makes these TiO2 scaffolds particularly effective for superior degradation of methylene blue with the enhanced rate constant and efficient disinfection of E. coli and S. aureus under UV light. The macrosize and mechanical stability of these purely TiO2 beaded architectures have several potential advantages over conventional TiO2 nanocomposites and slurry systems to address the inherent bottlenecks of secondary contamination, difficult operation and energy-intensive post-recovery processes that are indeed deemed to be the barriers to develop practically useful water treatment technologies.

Salmonella typhi infections are difficult to treat due to poor penetration of current antibiotic ciprofloxacin (CIP) modalities into the intracellular compartments of macrophages owing to poor solubilization and oral bioavailability. Poor penetration and dissolution of CIP lead to development of intracellular pathogens induced multi-drug resistance and resistant biofilms formation. Here we developed a novel strategy for the design and development of mucopenetrating self-emulsifying drug delivery system (SEDDS) of CIP to target intracellular Salmonella typhi bacterium with high specificity and selectivity. Oleic oil, Tween 80, and PEG 200 were selected as oil, surfactant and co-surfactant based on solubilizing capacity and pseudo ternary diagram emulsification capability. Mucopenetration feature of the SEDDS was enhanced by inclusion of poly-L-lysine functionalized carbohydrates (mannose, preactivated hyaluronic acid) co-block pluronic F127 (PLL-M-PTHA-F127) polymeric excipient. PLL-M-PTHA-F127 was developed as an amphiphilic muco-penetrating targeted anti-bacterial biological entity for intracellular targeting of Salmonella typhi infection reservoirs. Characterization of these self-nanoemulsifying carriers was carried out via dynamic light scattering (DLS), transmission electron microscopy (TEM) and fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), x-ray diffraction (XRD) and thermogravimetric analysis (TGA) The observed hydrodynamic diameter of PLL-M-PTHA-F 127 self- nano emulsifying drug delivery system (SEDDS) was 247 nm with low PDI and negatively charged zeta potential showing the stabilization of as-prepared formulation. In vitro drug release kinetics of nanocarriers exhibited 85% sustained release within 72 h under sink conditions. PLL-M-PTHA-F127 SEDDS of CIP showed very strong killing capability against Salmonella typhi strains even at lowest concentrations as compared to CIP and were found to be hemocompatible and biocompatible. The intracellular Salmonella typhi survival rate has been minimized with PLL-M-PTHA-F127 SEDDS as compared to CIP alone. Fluorescence microscopy images confirmed the proficient cellular uptake within the intracellular compartment of macrophages and rapid gallstone biofilm dispersion/clearance activity as compared to other formulations and CIP. In summary, PLL-M-PTHA-F127-SEDDS of CIP seemed to be an ideal candidate for eradication of Salmonella typhi intracellularly.

Hydroxyethylcellulose succinate-Na (HEC-Suc-Na) was designed and evaluated for removal of some heavy metal ions from aqueous solution. Pristine sorbent HEC-Suc-Na was thoroughly characterized by FTIR and solid-state CP/MAS 13C NMR spectroscopy, SEM-EDS and zero point charge analyses. Langmuir isotherm, pseudo second order kinetic and ion exchange models provided best fit to the experimental data of sorption of metal ions. Maximum sorption capacities of supersorbent HEC-Suc-Na for sorption of heavy metal ions from aqueous solution as calculated by Langmuir isotherm model were found to be 1000, 909.09, 666.6, 588 and 500 mg g−1 for Pb(II), Cr(VI), Co(II), Cu(II) and Ni(II), respectively. Competitive sorption of these heavy metal ions was carried out from galvanic and nuclear waste water simulated environment. The negative values of ΔG° and ΔH° indicated spontaneity and exothermic nature of sorption. The sorbent was efficiently regenerated with no significant decrease in sorption capacity after five cycles.