Excellent Adsorption of Lead (II) and Chromium (VI) from Water Using Zwitterions (-NH3+ and -COO-) Functionalized Nano Lanthanum Oxide: Kinetic, Isotherm, Thermodynamic, and Surface Mechanism.

Zwitterion amino acid l-cysteine functionalized lanthanum oxide nanoparticles (l-Cyst-La2O3 NPs) have been synthesized for the first time with lanthanum acetate as the precursor, NH4OH as the base, and l-cysteine as the in situ functionalized mediator. The typical size of l-Cyst-La2O3 NPs was obtained in the range of 15-20 nm from the TEM technique. A cytotoxicity test of l-Cyst-La2O3 NPs was performed in Raw 264.7 cell lines, which were shown to be highly biocompatible. The point zero charge pH (pHPZC) of bare and l-Cyst functionalized La2O3 NPs was obtained at pH 6 and 2. The maximum uptake capacities of l-Cyst-La2O3 NPs at temperatures 25-45 °C were obtained as 137-282 mg/g for Pb2+ and 186-256 mg/g for Cr6+. All of these values are much higher than those reported in the literature with other nanomaterials. The presence of -SH, -NH2, and -COOH functional groups in zwitterion l-cysteine provides multiple binding sites leading to the high adsorption of Pb2+ and Cr6+. Five-cycle desorption studies were successfully performed to regenerate the spent l-Cyst-La2O3 NPs.

Electrochemically microplastic detection using chitosan-magnesium oxide nanosheet.

Microplastics, an invisible threat, are emerging as serious pollutants that continuously affect health by interrupting/contaminating the human cycle, mainly involving food, water, and air. Such serious scenarios raised the demand for developing efficient sensing systems to detect them at an early stage efficiently and selectively. In this direction, the proposed research reports an electrochemical hexamethylenetetramine (HMT) sensing utilizing a sensing platform fabricated using chitosan-magnesium oxide nanosheets (CHIT-MgO NS) nanocomposite. HMT is considered as a hazardous microplastic, which is used as an additive in plastic manufacturers and has been selected as a target analyte. To fabricate sensing electrodes, a facile co-precipitation technique was employed to synthesize MgO NS, which was further mixed with 1% CHIT solution to form a CHIT_MgO NS composite. Such prepared nanocomposite solution was then drop casted to an indium tin oxide (ITO) to fabricate CHIT_MgO NS/ITO sensing electrode to detect HMT electrochemically using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. To determine the limit of detection (LOD) and sensitivity, DPV was performed. The resulting calibrated curve for HMT, ranging from 0.5 µM to 4.0 µM, exhibited a sensitivity of 12.908 µA (µM)-1 cm-2 with a detection limit of 0.03 µM and a limit of quantitation (LOQ) of 0.10 µM. Further, the CHIT_MgO NS/ITO modified electrode was applied to analyze HMT in various real samples, including river water, drain water, packaged water, and tertiary processed food. The results demonstrated the method's high sensitivity and suggested its potential applications in the field of microplastic surveillance, with a focus on health management.

Granular Hemostatic Composite of Alginate, Calcium, and Zinc for Rapid and Effective Management of Post-Traumatic Hemorrhage.

Post-traumatic hemorrhage, which can result from accidents or battlefield injuries, is a significant global concern due to the high prehospital mortality rate. Substantial efforts have been made to develop hemostatic agents that can effectively reduce hemorrhage in the immediate aftermath of a traumatic event. The present study investigated the potential efficacy of Ca2+ and Zn2+ supplemented sodium alginate-based dry hemostatic particles (SA-CZ DHP) to manage excessive blood loss or post-traumatic hemorrhage. SA-CZ DHP were developed, followed by their physical and biochemical characterization, cytocompatibility and hemocompatibility testing, and critical evaluation of the hemostatic potential in vitro and in vivo. The safe SA-CZ DHP showed high absorption and accelerated blood clotting kinetics with reduced coagulation time (≈70%, p < 0.0001) in whole human blood, observed with insignificant hemolysis and uninterrupted RBC morphology. SA-CZ DHP significantly reduced the mean blood loss (≈90% in SD rats tail incision), and bleeding time (≈60% in BALB/c mice tail incision) was at par with commercially available Celox hemostatic granules. In conclusion, the biocompatible SA-CZ DHP exhibited rapid and effective management of excessive blood loss. It is also pertinent to note that the developed formulation could be a cost-effective alternative to its commercial counterparts.

Nano-modified screen-printed electrode-based electrochemical immunosensors for oral cancer biomarker detection in undiluted human serum and saliva samples.

This proposed work reports the development of in-house made conductive ink-based screen-printed electrodes (SPEs) for label-free detection of oral cancer biomarkers. Carbon ink synthesis includes graphite powder, gum arabic, and water. The selectivity test of the fabricated SPE involves immobilizing antibodies specific to biomarkers and challenges with redox-active interference, other serum molecules, and non-target biomarkers. Three different biomarkers, cytokeratin-19 fragment (CYFRA 21-1), interleukin 8 (IL-8), and tumor protein p53 (TP-53), act as target entities for the detection of oral cancer in patients' samples (serum, N = 28, and saliva, N = 16) at an early stage. The standard technique enzyme-linked immunosorbent assay (ELISA) was employed to estimate the concentration of the biomarkers in serum and saliva samples. SPEs contain amine (-NH2) functional groups involved in covalent bonding with the carboxyl (-COOH) groups of antibody molecules. These immunosensors exhibited remarkably lower detection limits of 829.5 pg mL-1, 0.543 pg mL-1, and 1.165 pg mL-1, and excellent sensitivity of 0.935 µA mL pg-1 cm-1, 0.039 µA mL pg-1 cm-1, and 0.008 µA mL pg-1 cm-1 for CYFRA 21-1, IL-8, and TP-53 biomarkers, respectively. This sensing platform does not require any functionalization for biomolecule immobilization. Thus, it is a cost-effective, disposable, flexible, miniaturized, and sensitive strip to detect oral cancer biomarkers.

Fabrication of Mesoporous Silica Nanoparticle-Decorated Graphene Oxide Sheets for the Effective Removal of Lead (Pb2+) from Water.

Mesoporous silica nanoparticle-decorated graphene oxide nanosheets (MSiO2-GO) were synthesized and characterized for the active removal of lead (Pb2+) from the water. MSiO2 NPs were prepared via an ultrasonication method using tetraethyl orthosilicate (TEOS), and GO sheets were obtained via a modified Hummers' method. X-ray diffraction, UV-vis spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive X-ray spectroscopy specified the composition of MSiO2 NPs and GO sheets. The surface charge and texture of the MSiO2-GO nanosheets were obtained using the ζ-potential technique and by field emission scanning electron microscopy. The relative cytotoxicity test of MSiO2 NPs and MSiO2-GO nanosheets was performed on Murine Raw 264.7 cells before implying the treatment of water. Adsorption of Pb2+ ions on MSiO2-GO nanosheets was examined at various parameters such as different aqueous pH values (2.0-10.0), MSiO2-GO nanosheet doses (3, 5, 10, 15, 20 mg L-1), time intervals (2-30 min), and temperatures (25-45 °C). About 90% of Pb2+ ions were removed from water within 30 min (MSiO2-GO dose: 15 mg L-1; initial Pb2+ ions: 50 mg L-1; temperature: 25 °C; shaking speed: 200 rpm). The maximal uptake of Pb2+ was obtained at solution pH 6.0. Pseudo-first- and pseudo-second-order kinetic rate equations describe the sorption dynamic data. Pb2+ sorption isotherms were modeled using the Freundlich and Langmuir isotherm models. The possible mechanism of binding of Pb2+ ions onto MSiO2-GO nanosheets has been discussed. The exhausted MSiO2-GO nanosheets were successfully regenerated using 0.005 M HNO3 as the desorbing agent.

Polyvinyl alcohol-derived-carbon quantum dots based fluorometric "On-Off" probe for moxifloxacin detection in milk and egg samples.

Unconditional use of antibiotics triggered the process of bacterial resistance and causes major health problems. Nowadays, antibiotics majorly used in animals not only for infection treatment but also as mass promotor. The excess amount of antibiotics residue in animal derived foods which accelerate antibiotic resistance (ABR). So, here, a simple and quick carbon quantum dots(CQDs) based fluorometric "On-Off" probe was developed for detection of moxifloxacin (MOXI) in milk and egg samples. The CQDs emits blue emission and are uniformly distributed with average particle size 5.9 ± 0.22 nm. With MOXI, fluorescence intensity of CQDs at 372 nm decreased due to inner filter effect (IFE) and a new peak appeared at 508 nm correspondence to MOXI. The probe shows linear response with MOXI concentration varies as 0.025 µM - 15.0 µM with lower detection limit (LOD) of 6.34 nM. The real sample applicability test proved that the sensors have excellent efficacy for food applications.

Enhanced Electrochemical Biosensing of the Sp17 Cancer Biomarker in Serum Samples via Engineered Two-Dimensional MoS2 Nanosheets on the Reduced Graphene Oxide Interface.

In the present investigation, we reported a label-free and highly effective immunosensor for the first time employing a nanostructured molybdenum disulfide nanosheets@reduced graphene oxide (nMoS2 NS@rGO) nanohybrid interface for the determination of sperm protein 17 (Sp17), an emerging cancer biomarker. We synthesized the nMoS2 NS@rGO nanohybrid using a one-step hydrothermal technique and then functionalized it with 3-aminopropyltriethoxysilane (APTES). Furthermore, the anti-Sp17 monoclonal antibodies were covalently attached to the APTES/nMoS2 NS@rGO/indium tin oxide (ITO) electrode utilizing 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide-N-hydroxy succinimide (EDC-NHS) coupling chemistry. Bovine serum albumin (BSA) was then used to block nonspecific binding regions on the anti-Sp17/APTES/nMoS2 NS@rGO/ITO bioelectrode. The morphological and structural features of the synthesized nanohybrid and the modified electrodes were studied using transmission electron microscopy, scanning electron microscopy with energy dispersive X-ray (EDX) composition studies, atomic force microscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The immunoreaction between the Sp17 antigen and anti-Sp17 antibodies on the surface of the BSA/anti-Sp17/APTES/nMoS2 NS@rGO/ITO sensing bioelectrode was applied as the basis for the detection technique, which measured the electrocatalytic current and impedimetric response change. The designed BSA/anti-Sp17/APTES/nMoS2 NS@rGO/ITO bioelectrode showed improved amperometric and impedimetric biosensing performance in the response studies, including remarkable sensitivity (23.2 µA ng-1mL cm-2 and 0.48 kΩ mL ng-1 cm-2), wider linearity (0.05-8 and 1-8 ng mL-1), an excellent lower detection limit (0.13 and 0.23 ng mL-1), and a rapid response time of 20 min. The biosensor exhibited impressive storage durability lasting 7 weeks and showed remarkable precision in identifying Sp17 in serum samples from cancer patients, as confirmed using the enzyme-linked immunosorbent assay method.

Graphene oxide-Mn3O4nanocomposites for advanced electrochemical biosensor for fumonisin B1 detection.

Occurrence of mycotoxins in food samples threat to its safety issue due to the presence of high toxicity and carcinogenic behavior, thus requiring highly sensitive and selective detection. Herein, the trimanganese tetraoxide (Mn3O4) nanoparticles in combination with graphene oxide (GO) nanocomposite were used to enhance the electrochemical performance for fabrication of electrochemical biosensor for fumonisin B1 (FB1) detection. The various characterization tools were used to validate the fabrication of GOMn3O4nanocomposites. To fabricate the electrochemical biosensor on an indium tin oxide (ITO) coated glass substrate, a thin film of GOMn3O4nanocomposite was prepared using electrophoretic deposition technique, and antibodies (ab-FB1) were immobilized onto the electrode for selective FB1 detection. The differential pulse voltammetry technique was used to observe the sensing performance. The non-binding sites of the ab-FB1 on the immunoelectrode were blocked with bovine serum albumin (BSA). The biosensor electrode was fabricated as BSA/ab-FB1/GOMn3O4/ITO for the detection of FB1. The sensitivity of the biosensor was obtained as 10.08µA ml ng-1cm-2in the detection range of 1 pg ml-1to 800 ng ml-1with a limit of detection of 0.195 pg ml-1. In addition, the recovery of BSA/ab-FB1/GOMn3O4/ITO immunoelectrodes was also performed on sweet corn samples and is calculated to be 98.91%.

FRET Based Biosensor: Principle Applications Recent Advances and Challenges.

Förster resonance energy transfer (FRET)-based biosensors are being fabricated for specific detection of biomolecules or changes in the microenvironment. FRET is a non-radiative transfer of energy from an excited donor fluorophore molecule to a nearby acceptor fluorophore molecule. In a FRET-based biosensor, the donor and acceptor molecules are typically fluorescent proteins or fluorescent nanomaterials such as quantum dots (QDs) or small molecules that are engineered to be in close proximity to each other. When the biomolecule of interest is present, it can cause a change in the distance between the donor and acceptor, leading to a change in the efficiency of FRET and a corresponding change in the fluorescence intensity of the acceptor. This change in fluorescence can be used to detect and quantify the biomolecule of interest. FRET-based biosensors have a wide range of applications, including in the fields of biochemistry, cell biology, and drug discovery. This review article provides a substantial approach on the FRET-based biosensor, principle, applications such as point-of-need diagnosis, wearable, single molecular FRET (smFRET), hard water, ions, pH, tissue-based sensors, immunosensors, and aptasensor. Recent advances such as artificial intelligence (AI) and Internet of Things (IoT) are used for this type of sensor and challenges.

Electrochemical Detection of Vibrio cholerae by Amine Functionalized Biocompatible Gadolinium Oxide Nanoparticles.

Herein, we report the biocompatible amine-functionalized gadolinium oxide nanoparticles (Gd2O3 NPs) for the possibility of electrochemical detection of Vibrio cholerae (Vc) cells. The microwave irradiation process is applied to synthesize Gd2O3 NPs. The amine (NH2) functionalization is carried out via overnight stirring with 3(Aminopropyl)triethoxysilane (APTES) at 55 °C. The size of NPs amine functionalized APETS@Gd2O3 NPs are determined by transmission electron microscopy (TEM). APETS@Gd2O3 NPs are further electrophoretically deposited onto indium tin oxide (ITO) coated glass substrate to obtain working electrode surface. The monoclonal antibodies (anti-CT) specific to cholera toxin associated to Vc cells are covalently immobilized onto the above electrodes using EDC-NHS chemistry and further BSA is added to obtain the BSA/anti-CT/APETS@Gd2O3/ITO immunoelectrode. Further, this immunoelectrode shows the response for cells in CFU range from 3.125 × 106 to 30 × 106 and is very selective with sensitivity and LOD 5.07 mA CFUs mL cm-2 and 0.9375 × 106 CFU respectively. To establish a future potential for APTES@Gd2O3 NPs in field of biomedical applications and cytosensing, the effect of APTES@Gd2O3 NPs on mammalian cells is also observed using in vitro cytotoxicity assay and cell cycle analysis.

Biocompatible epoxysilane substituted polymer-based nano biosensing platform for label-free detection of cancer biomarker SP17 in patient serum samples.

Herein, we report the results of the studies relating to developing a simple, sensitive, cost-effective, and disposable electrochemical-based label-free immunosensor for real-time detection of a new cancer biomarker, sperm protein-17 (SP17), in complex serum samples. An indium tin oxide (ITO) coated glass substrate modified with self-assembled monolayers (SAMs) of 3-glycidoxypropyltrimethoxysilane (GPTMS) was functionalized via covalent immobilization of monoclonal anti-SP17 antibodies using EDC(1-(3-(dimethylamine)-propyl)-3-ethylcarbodiimide hydrochloride) - NHS (N-hydroxy succinimide) chemistry. The developed immunosensor platform (BSA/anti-SP17/GPTMS@SAMs/ITO) was characterized via scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle (CA), Fourier transform infrared (FT-IR) spectroscopic, and electrochemical techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) techniques. The fabricated BSA/anti-SP17/GPTMS@SAMs/ITO immunoelectrode platform was used to measure changes in the magnitude of the current of the electrodes through an electrochemical CV and DPV technique. A calibration curve between current and SP17 concentrations exhibited a broad linear detection range of (100-6000 & 50-5500 pg mL-1), with enhanced sensitivity (0.047 & 0.024 µA pg mL-1 cm-2), limit of detection (LOD) and limit of quantification (LOQ) of 47.57 & 142.9 pg mL-1 and 158.58 & 476.3 pg mL-1, by CV and DPV technique, respectively with a rapid response time of 15 min. It possessed exceptional repeatability, outstanding reproducibility, five-time reusability, and high stability. The biosensor's performance was evaluated in human serum samples, giving satisfactory findings obtained via the commercially available enzyme-linked immunosorbent assay (ELISA) technique, proving the clinical applicability for early diagnosis of cancer patients. Moreover, various in vitro studies in murine fibroblast cell line L929 have been performed to assess the cytotoxicity of GPTMS. The results demonstrated that GPTMS has excellent biocompatibility and can be used for biosensor fabrication.

Gold@Carbon Quantum Dots Nanocomposites Based Two-In-One Sensor: A Novel Approach for Sensitive Detection of Aminoglycosides Antibiotics in Food Samples.

Antibiotics are life-saving drugs for humans, but their unwanted use leads to antibacterial resistance (ABR) and causes serious health problems. The excess of these antibiotics entered to the food chain and caused food contamination. Here, Au@CQDs nanocomposites (NCs) was used as a two-in-one sensor to detect two antibiotics. The color change of AuNCs and fluorescence resonance energy transfer are two distance-dependent phenomena used as sensing mechanisms. In the sensing process, Au@CQDs NCs change their color, enhancing the fluorescence intensity of NCs in the presence of Gentamicin (GENTA) and Kanamycin (KMC) antibiotics. The limit of detection of 116 nM and 133 nM for GENTA and 195 nM and 120 nM for KMC have been achieved with colorimetric and fluorimetric readout, respectively. The practicality of the reported sensor was evaluated in real spiked samples and showed excellent recovery efficiency. Therefore this two-in-one sensor can be used for the food monitoring system.

Recent trends in nanocomposite packaging films utilising waste generated biopolymers: Industrial symbiosis and its implication in sustainability.

Uncontrolled waste generation and management difficulties are causing chaos in the ecosystem. Although it is vital to ease environmental pressures, right now there is no such practical strategy available for the treatment or utilisation of waste material. Because the Earth's resources are limited, a long-term, sustainable, and sensible solution is necessary. Currently waste material has drawn a lot of attention as a renewable resource. Utilisation of residual biomass leftovers appears as a green and sustainable approach to lessen the waste burden on Earth while meeting the demand for bio-based goods. Several biopolymers are available from renewable waste sources that have the potential to be used in a variety of industries for a wide range of applications. Natural and synthetic biopolymers have significant advantages over petroleum-based polymers in terms of cost-effectiveness, environmental friendliness, and user-friendliness. Using waste as a raw material through industrial symbiosis should be taken into account as one of the strategies to achieve more economic and environmental value through inter-firm collaboration on the path to a near-zero waste society. This review extensively explores the different biopolymers which can be extracted from several waste material sources and that further have potential applications in food packaging industries to enhance the shelf life of perishables. This review-based study also provides key insights into the different strategies and techniques that have been developed recently to extract biopolymers from different waste byproducts and their feasibility in practical applications for the food packaging business.

Amine Functionalized Gadolinium Oxide Nanoparticles-Based Electrochemical Immunosensor for Cholera.

Herein, we report the synthesis and functionalization of gadolinium oxide nanoparticles (Gd2O3 NPs) to fabricate a highly efficient immunosensor for the detection of Vibrio cholera toxin (CT). Gd2O3 NPs were produced in a straightforward manner utilizing the microwave irradiation technique using a domestic microwave oven. X-ray diffraction, transmission electron microscopy, and spectroscopic techniques were used to characterize the structural and physical aspects of Gd2O3 NPs. The Gd2O3 NPs were then functionalized with 3-(Aminopropyl) triethoxysilane (APTES) and electrophoretically deposited onto an ITO-coated glass substrate. The anti-CT monoclonal antibodies were covalently attached to the APTES-Gd2O3/ITO electrode via EDC-NHS chemistry, followed by bovine serum albumin (BSA). For CT detection, electrochemical response experiments using BSA/anti-CT/APTES-Gd2O3/ITO immunoelectrodes were carried out (5-700 ng mL-1). The immunoelectrode demonstrated an outstanding electrochemical reaction against CT, with a sensitivity of 8.37 mA ng-1 mL cm-2 and a detection limit of 1.48 ng mL-1.

Facile synthesis of carbon dots via pyrolysis and their application in photocatalytic degradation of rhodamine B (RhB).

Carbon Quantum dot (CQDs) is one of the newest materials in carbon-based nanomaterials. It is pertinent to study the synthesis and the application of these carbon dots. Here we have studied the effect of precursor on the optical, morphological, and photocatalytic properties of CQDs. We have synthesized CQDs using pyrolysis method using the precursors citric acid, urea, polyethyleneimine. We have synthesized two samples: CQD-S1; synthesized using urea and polyethyleneimine, and CQD-S2; synthesized using citric acid and polyethyleneimine. In optical properties study two distinct peaks have been obtained at 243 nm and 345 nm for CQD-S1, and at 265 nm and 335 nm for CQD-S2. In fluorescence study, the maximum emission was found at excitation wavelength of 340 nm for CQD-S1 and at excitation wavelength of 350 nm for CQD-S2. In morphological studies, Transmission Electron Microscope (TEM) revealed particle size of sample CQD-S1 and CQD-S2 were 1.91 nm and 1.61 nm, respectively. EDX confirmed the elemental composition in both samples. The rhodamine B (RhB) dye degradation percentages in dark and under visible and UV light were found to 6, 13, and 98.4% respectively for CQD-S1. Similarly, dye degradation for CQD-S2 were 7, 11, and 99.63%, respectively. Effective degradation of photocatalysis performed under UV-light within 100 min using mineralization process.

Co-Application of Silver Nanoparticles and Symbiotic Fungus Piriformospora indica Improves Secondary Metabolite Production in Black Rice.

In the current research, unique Nano-Embedded Fungus (NEF), made by the synergic association of silver nanoparticles (AgNPs) and endophytic fungus (Piriformospora indica), is studied, and the impact of NEF on black rice secondary metabolites is reported. AgNPs were synthesized by chemical reduction process using the temperature-dependent method and characterized for morphological and structural features through UV visible absorption spectroscopy, zeta potential, XRD, SEM-EDX, and FTIR spectroscopy. The NEF, prepared by optimizing the AgNPs concentration (300 ppm) in agar and broth media, showed better fungal biomass, colony diameter, spore count, and spore size than the control P. indica. Treatment with AgNPs, P. indica, and NEF resulted in growth enhancement in black rice. NEF and AgNPs stimulated the production of secondary metabolites in its leaves. The concentrations of chlorophyll, carotenoids, flavonoids, and terpenoids were increased in plants inoculated with P. indica and AgNPs. The findings of the study highlight the synergistic effect of AgNPs and the fungal symbionts in augmenting the secondary metabolites in leaves of black rice.

Development of copper impregnated bio-inspired hydrophobic antibacterial nanocoatings for textiles.

Due to their bactericidal and fluid repellent capabilities, antimicrobial textiles with hydrophobic properties have aroused a lot of interest in healthcare, hygiene, air purifiers, water purification systems, food packaging, and other domains. Silver and silver-derived compounds have long been employed in antimicrobial coatings; nevertheless, they are costly, limiting their widespread use. In this work, we combined mussel-inspired polydopamine (pDA) coating chemistry with graphene oxide (GO) and antimicrobial copper compounds (Cu(NO3)2, CuCl2, Cu nanoparticles (CuNPs), and Cu-Carbon nanofibers (Cu-CNF)) to create hydrophobic antimicrobial nanocoatings on cotton fabric. The structural, morphological, wettability, and antibacterial characteristics of the produced coatings were evaluated. The fabric coated with Cu(NO3)2 and CuNPs had good hydrophobicity, which was stabilized for 30 min following GO integration. The coated fabric with GO and CuNPs showed 100% bacterial inhibition for S. aureus and a 99.995% reduction for P. aeruginosa bacteria. Overall, this bioinspired approach to developing antimicrobial coatings on fabric utilizing Cu(NO3)2 and CuNPs with GO shows a lot of promise in preventing the transmission of bacterial and viral infections through contaminated garments and has potential in designing clothing for healthcare settings such as PPEs, gowns, aprons, face mask filters, curtains, and so on.

Nanomaterial-Based Electrochemical Nanodiagnostics for Human and Gut Metabolites Diagnostics: Recent Advances and Challenges.

Metabolites are the intermediatory products of metabolic processes catalyzed by numerous enzymes found inside the cells. Detecting clinically relevant metabolites is important to understand their physiological and biological functions along with the evolving medical diagnostics. Rapid advances in detecting the tiny metabolites such as biomarkers that signify disease hallmarks have an immense need for high-performance identifying techniques. Low concentrations are found in biological fluids because the metabolites are difficult to dissolve in an aqueous medium. Therefore, the selective and sensitive study of metabolites as biomarkers in biological fluids is problematic. The different non-electrochemical and conventional methods need a long time of analysis, long sampling, high maintenance costs, and costly instrumentation. Hence, employing electrochemical techniques in clinical examination could efficiently meet the requirements of fully automated, inexpensive, specific, and quick means of biomarker detection. The electrochemical methods are broadly utilized in several emerging and established technologies, and electrochemical biosensors are employed to detect different metabolites. This review describes the advancement in electrochemical sensors developed for clinically associated human metabolites, including glucose, lactose, uric acid, urea, cholesterol, etc., and gut metabolites such as TMAO, TMA, and indole derivatives. Different sensing techniques are evaluated for their potential to achieve relevant degrees of multiplexing, specificity, and sensitivity limits. Moreover, we have also focused on the opportunities and remaining challenges for integrating the electrochemical sensor into the point-of-care (POC) devices.

Environmental friendly Polyacrylonitrile nanofiber mats encapsulated and coated with green algae mediated Titanium oxide nanoparticles for efficient oil spill adsorption.

Oil spill causes extreme environmental damage, from aquatic life to seabirds, disrupting the entire ecosystem. Herein, we have synthesized high scale, economical and bio-compatible, green algae mediated Titanium oxide (TiO2) nanoparticles and Polyacrylonitrile (PAN) nanofiber mats. We have studied the effect of encapsulation and coating of TiO2 nanoparticles over nanofiber mats for highly efficient oil spill adsorption. TiO2 encapsulated and coated PAN (TECP) nanofibers showed a maximum of 62.34 g g-1 adsorption capacity of petroleum oil from the water surface. Moreover, the composite mats show maximum adsorption within 45 s for up to 5 repeated cycles. Further, it has been observed that the adsorption capacity has increased by increasing the weight of the composite nanofiber mats, which confirms its commercial applicability. Thus, this work provides rapid, large-scale, economical, bio-compatible, and highly effective adsorbents for oil spill cleaning and extraction over natural waterbodies.

Fabrication of alkoxysilane substituted polymer-modified disposable biosensing platform: Towards sperm protein 17 sensing as a new cancer biomarker.

SP17 is a mammalian protein found in the testis and spermatozoa that have been identified as a tumor-associated antigen in a range of human cancers. A unique method for fabricating the first ultrasensitive, selective, and label-free immunosensor for the detection of SP17, a new cancer biomarker in complicated serum samples, is presented in this paper. This immunosensor was also the first biosensor built using a disposable ITO sheet modified with an aminosilane known as APTMS as an immobilization platform for fabricating the SP17 biosensor. The immobilization of chemical and biological species onto the electrode surface was cross-verified by various analytical and morphological techniques. Stepwise modifications done on the immunoelectrodes were also studied using electrochemical techniques. Selective interaction between anti-SP17 and SP17 with varying concentrations (100-5000 pg mL-1) was measured with the DPV technique. The immunosensor exhibited low LOD and LOQ of 70.07 and 233.57 pg mL-1, respectively, with a sensitivity of 0.013 µA mL pg-1 cm-2. The fabricated immunosensor performance was analyzed by quantifying the SP17 concentrations in patient serum samples. The data obtained from the developed immunosensor demonstrated excellent reproducibility, repeatability, and selectivity among various interferants, including cancer biomarkers. Further, the observed results have been validated via ELISA, which showed good agreement with the electrochemical results. This could establish a new platform for detecting other cancer biomarkers and can be employed for clinical diagnostics applications.