Exploring the antibiofilm and toxicity of tin oxide nanoparticles: Insights from in vitro and in vivo investigations.

BACKGROUND INFORMATION: The advancement of biological-mediated nanoscience towards higher levels and novel benchmarks is readily apparent, owing to the use of non-toxic synthesis processes and the incorporation of various additional benefits. This study aimed to synthesize stable tin oxide nanoparticles (SnO2-NPs) using S. rhizophila as a mediator. METHODS: The nanoparticles that were created by biosynthesis was examined using several analytical techniques, including Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), UV-visible (UV-vis) spectroscopy, and energy dispersive X-ray spectroscopy (EDS). RESULTS: The results obtained from the characterization techniques suggest that S. rhizophila effectively catalyzed the reduction of SnCl2 to SnO2-NPs duration of 90 min at ambient temperature with the ƛmax of 328 nm. The size of the nano crystallite formations was measured to be 23 nm. The present study investigates nanoscale applications' antibacterial efficacy against four bacterial strains, including Klebsiella Sp, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The observed zone of inhibition for the nanoparticles (NPs) varied from 10 to 25 mm. The research findings demonstrate that the nanoparticles (NPs) are effective as antibacterial, phytotoxic, and cytotoxic agents.

Self-assembled peptide nanotubes (SPNTs)/SnO2nanocomposites for high-performance NO2sensing at room temperature.

Nitrogen dioxide (NO2) is a major pollutant that poses significant risks to sustainable human life. As a result, a growing focus has been placed on the development of highly selective and sensitive gas sensors for NO2. Traditional cutting-edge non-organic NO2gas detectors often necessitate stringent production conditions and potentially harmful materials, which are not environmentally friendly, and these shortcomings have limited their widespread practical use. To overcome these challenges, we synthesized self-assembled peptide nanotubes (SPNTs) through a molecular self-assembly process. The SPNTs were then combined with SnO2in varying proportions to construct NO2gas sensors. The design of this sensor ensured efficient electron transfer and leverage the extensive surface area of the SPNTs for enhanced gas adsorption and the effective dispersion of SnO2nanoparticles. Notably, the performance of the sensor, including its sensitivity, response time, and recovery rate, along with a lower detection threshold, could be finely tuned by varying the SPNTs content. This approach illustrated the potential of bioinspired methodologies, using peptide self-assemblies, to develop integrated sensors for pollutant detection, providing a significant development in environmentally conscious sensor technology.

Rapid Surface Charge Mapping Based on a Liquid Crystal Microchip.

Rapid surface charge mapping of a solid surface remains a challenge. In this study, we present a novel microchip based on liquid crystals for assessing the surface charge distribution of a planar or soft surface. This chip enables rapid measurements of the local surface charge distribution of a charged surface. The chip consists of a micropillar array fabricated on a transparent indium tin oxide substrate, while the liquid crystal is used to fill in the gaps between the micropillar structures. When an object is placed on top of the chip, the local surface charge (or zeta potential) influences the orientation of the liquid crystal molecules, resulting in changes in the magnitude of transmitted light. By measuring the intensity of the transmitted light, the distribution of the surface charge can be accurately quantified. We calibrated the chip in a three-electrode configuration and demonstrated the validity of the chip for rapid surface charge mapping using a borosilicate glass slide. This chip offers noninvasive, rapid mapping of surface charges on charged surfaces, with no need for physical or chemical modifications, and has broad potential applications in biomedical research and advanced material design.

Ultrasound-driven facile fabrication of Pd doped SnO2 hierarchical superstructures: Structural, growth mechanism, dermatoglyphics, and anti-cancer activity.

This research introduces a novel method that leverages Spirulina extract (S.E) as a bio-surfactant in the ultrasound-assisted synthesis (UAS) of Pd3+ (0.25-10 mol%) doped tin oxide (SnO2) self-assembled superstructures. Nanotechnology has witnessed significant advancements in recent years, driven by the exploration of novel synthesis methods and the development of advanced nanomaterials tailored for specific applications. Metal oxide nanoparticles, particularly SnO2, have garnered considerable attention due to their versatile properties and potential applications in various fields, including gas sensing, catalysis, and biomedical engineering. The study explores how varying influential parameters like S.E concentration, sonication time, pH, and sonication power can influence the resulting superstructures' morphology, size, and shape. A theoretical model for forming different hierarchical superstructures (HS) is proposed. X-ray diffraction (XRD) analysis confirms the crystalline tetragonal rutile phase of the SnO2:Pd HS. Raman spectroscopy reveals a red shift in the A1g mode, indicating phonon confinement due to various defects in the SnO2 structure. Further characterization using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) provides insights into particle size, surface morphology, elemental composition, and binding energy. The study also demonstrates the application of optimized SnO2:3Pd HS in developing latent fingerprints (LFPs) on different surfaces using a simple powder dusting (PD) method, with the fingerprints (FPs) visualized under normal light. A mathematical model developed in Python-based software is used to analyze various features of the developed FPs, including pore properties such as number, position, inter-spacing, area, and shape. Additionally, an in vitro MTT assay shows concentration-dependent anticancer activity of SnO2:3Pd nanoparticles (NPs) on MCF7 cell lines, highlighting their potential as a promising cancer treatment option. Overall, the study suggests that the optimized HS can serve as multifunctional platforms for biomedical and dermatoglyphics applications, demonstrating the versatility and potential of the synthesized materials.

Efficient electrochemical degradation of ceftazidime by Ti3+ self-doping TiO2 nanotube-based Sb-SnO2 nanoflowers as an intermediate layer on a modified PbO2 electrode.

Ceftazidime (CAZ) is an emerging organic pollutant with a long-lasting presence in the environment. Although some PbO2 materials exhibit degradation capabilities, inefficient electron transport in the substrate layer and the problem of electrode stability still limit their use. Here, an interfacial design in which TiO2 nanotube arrays generate Ti3+ self-doping oxide substrate layers and highly active 3D Sb-SnO2 nanoflowers-like interlayers was used to prepare PbO2 anodes for efficient degradation of CAZ. Interestingly, after implementing Ti3+ self-doping in the PbO2 anode base layer and introducing 3D nanoflowers-like structures, the capacity for •OH generation increased significantly. The modified electrode exhibited 5-fold greater •OH generation capacity compared to the unmodified electrode, and a 2.7-fold longer accelerated electrode lifetime. The results indicate that interfacial engineering of the base and intermediate layers of the electrodes can improve the electron transfer efficiency, promote the formation of •OH, and extend the anode lifetime of the activated CAZ system.

Synergistic catalysis of TiO2/WO3 photoanode and Sb-SnO2 electrode with highly efficient ClO• generation for urine treatment.

Urine is the major source of nitrogen pollutants in domestic sewage and is a neglected source of H2. Although ClO• is used to overcome the poor selectivity and slow kinetics of urea decomposition, the generation of ClO• suffers from the inefficient formation reaction of HO• and reactive chlorine species (RCS). In this study, a synergistic catalytic method based on TiO2/WO3 photoanode and Sb-SnO2 electrode efficiently producing ClO• is proposed for urine treatment. The critical design is that TiO2/WO3 photoanode and Sb-SnO2 electrode that generate HO• and RCS, respectively, are assembled in a confined space through face-to-face (TiO2/WO3//Sb-SnO2), which effectively strengthens the direct reaction of HO• and RCS. Furthermore, a Si solar panel as rear photovoltaic cell (Si PVC) is placed behind TiO2/WO3//Sb-SnO2 to fully use sunlight and provide the driving force of charge separation. The composite photoanode (TiO2/WO3//Sb-SnO2 @Si PVC) has a ClO• generation rate of 260% compared with the back-to-bake assembly way. In addition, the electrons transfer to the NiFe LDH@Cu NWs/CF cathode for rapid H2 production by the constructed photoelectric catalytic (PEC) cell without applied external biasing potential, in which the H2 production yield reaches 84.55 µmol h-1 with 25% improvement of the urine denitrification rate. The superior performance and long-term stability of PEC cell provide an effective and promising method for denitrification and H2 generation.

Biocompatible Gold Nanoparticles-Modified Fluorine Doped Tin Oxide Electrode for the Fabrication of Enzyme-Free Glucose Sensor.

This work demonstrates the use of jute stick extract as a reducing and stabilizing agent for the synthesis of spherical gold nanoparticles (AuNPs). In UV-Vis spectroscopy, peak at 550 nm was used to confirm the formation of AuNPs. The spherical surface morphology of AuNPs was determined through SEM and TEM analysis. While XRD investigation revealed the crystallinity of the prepared AuNPs. To ensure the biocompatibility of synthesized AuNPs, a bacterial investigation was conducted with negative results towards bacterial strain. The, modified FTO with AuNPs were able to detect glucose in CV analysis and the constructed sensor displayed a wide linear range of 50 µM to 40 mM with a detection limit of 20 µM. Scan rate analysis was performed to determine the charge transfer coefficient (0.42) and Tafel slope (102 mV/decade). Furthermore, the interfacial surface mechanism is illustrated to understand the interaction of glucose with the electrode surface in an alkaline medium and the product formation through the dehydrogenation and hydrolysis process. The prepared sensor also showed good stability, reproducibility, and anti-interference capabilities. In the case of real sample analysis, we used a blood serum sample. A low RSD value (<10 %) suggests the practical use of AuNPs/FTO in real-life applications.

A self-powered electrochemical aptasensor for the detection of 17ß-estradiol based on carbon nanocages/gold nanoparticles and DNA bioconjugate mediated biofuel cells.

17ß-Estradiol (E2) is an important endogenous estrogen, which disturbs the endocrine system and poses a threat to human health because of its accumulation in the human body. Herein, a biofuel cell (BFC)-based self-powered electrochemical aptasensor was developed for E2 detection. Porous carbon nanocage/gold nanoparticle composite modified indium tin oxide (CNC/AuNP/ITO) and glucose oxidase modified CNC/AuNP/ITO were used as the biocathode and bioanode of BFCs, respectively. [Fe(CN)6]3- was selected as an electroactive probe, which was entrapped in the pores of positively charged magnetic Fe3O4 nanoparticles (PMNPs) and then capped with a negatively charged E2 aptamer to form a DNA bioconjugate. The presence of the target E2 triggered the entrapped [Fe(CN)6]3- probe release due to the removal of the aptamer via specific recognition, which resulted in the transfer of electrons produced by glucose oxidation at the bioanode to the biocathode and produced a high open-circuit voltage (EOCV). Consequently, a "signal-on" homogeneous self-powered aptasensor for E2 assay was realized. Promisingly, the BFC-based self-powered aptasensor has particularly high sensitivity for E2 detection in the concentration range of 0.5 pg mL-1 to 15 ng mL-1 with a detection limit of 0.16 pg mL-1 (S/N = 3). Therefore, the proposed BFC-based self-powered electrochemical aptasensor has great promise to be applied as a successful prototype of a portable and on-site bioassay in the field of environment monitoring and food safety.

Impact of Sn-doping on the optoelectronic properties of zinc oxide crystal: DFT approach.

This study aims to provide a concise overview of the behavior exhibited by Sn-doped ZnO crystals using a computational technique known as density functional theory (DFT). The influence of Sn doping on the electronic, structural, and optical properties of ZnO have been explored. Specifically, the wavelength dependent refractive index, extinction coefficient, reflectance, and absorption coefficient, along with electronic band gap structure of the Sn doped ZnO has been examined and analyzed. In addition, X-ray diffraction (XRD) patterns have been obtained to investigate the structural characteristics of Sn-doped ZnO crystals with varying concentrations of Sn dopant atoms. The incorporation of tin (Sn) into zinc oxide (ZnO) has been observed to significantly impact the opto-electronic properties of the material. This effect can be attributed to the improved electronic band structure and optical characteristics resulting from the tin doping. Furthermore, the controllable structural and optical characteristics of tin-doped zinc oxide will facilitate the development of various light-sensitive devices. Moreover, the impact of Sn doping on the optoelectronic properties of ZnO is thoroughly investigated and documented.

Efficient synthesis of 3D ZnO nanostructures on ITO surfaces for enhanced photoelectrochemical water splitting.

New photoactive materials with uniform and well-defined morphologies were developed for efficient and sustainable photoelectrochemical (PEC) water splitting and hydrogen production. The investigation is focused on hydrothermal deposition of zinc oxide (ZnO) onto indium tin oxide (ITO) conductive surfaces and optimization of hydrothermal temperature for growing uniform sized 3D ZnO morphologies. Fine-tuning of hydrothermal temperature enhanced the scalability, efficiency, and performance of ZnO-decorated ITO electrodes used in PEC water splitting. Under UV light irradiation and using eco-friendly low-cost hydrothermal process in the presence of stable ZnO offered uniform 3D ZnO, which exhibited a high photocurrent of 0.6 mA/cm2 having stability up to 5 h under light-on and light-off conditions. The impact of hydrothermal temperature on the morphological properties of the deposited ZnO and its subsequent performance in PEC water splitting was investigated. The work contributes to advancement of scalable and efficient fabrication technique for developing energy converting photoactive materials.

Nonaqueous Oxidation in DNA Microarray Synthesis Improves the Oligonucleotide Quality and Preserves Surface Integrity on Gold and Indium Tin Oxide Substrates.

Nucleic acids attached to electrically conductive surfaces are very frequently used platforms for sensing and analyte detection as well as for imaging. Synthesizing DNA on these uncommon substrates and preserving the conductive layer is challenging as this coating tends to be damaged by the repeated use of iodine and water, which is the standard oxidizing medium following phosphoramidite coupling. Here, we thoroughly investigate the use of camphorsulfonyl oxaziridine (CSO), a nonaqueous alternative to I2/H2O, for the synthesis of DNA microarrays in situ. We find that CSO performs equally well in producing high hybridization signals on glass microscope slides, and CSO also protects the conductive layer on gold and indium tin oxide (ITO)-coated slides. DNA synthesis on conductive substrates with CSO oxidation yields microarrays of quality approaching that of conventional glass with intact physicochemical properties.

One-step synthesis of Pt-Nd co-doped Ti/SnO2-Sb nanosphere electrodes used to degrade nitrobenzene.

Ti/SnO2-Sb electrodes possess high catalytic activity and efficiently degrade nitrobenzene (NB); however, their low service life limits their wide application. In this study, we used one-step hydrothermal synthesis to successfully prepare Pt-Nd co-doped Ti/SnO2-Sb nanosphere electrodes. Scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were applied to characterize the surface morphology, microstructure, and chemical composition of the electrodes, respectively. The electrochemical activity and stability of the electrodes were characterized via linear sweep and cyclic voltammetry, electrochemical impedance spectroscopy, and an accelerated service life test; their performance for NB degradation was also studied. An appropriate amount of Pt-Nd co-doping refined the average grain size of SnO2 and formed a uniform and compact coating on the electrode surface. The oxygen evolution potential, total voltammetric charge, and electron transfer resistance of the Ti/SnO2-Sb-Nd-Pt electrodes were 1.88 V, 3.77 mC/cm2, and 11.50 Ω, respectively. Hydroxy radical was the main active radical species during the electrolytic degradation of nitrobenzene with Ti/SnO2-Sb-Nd-Pt. After Pt-Nd co-doping, the accelerated service life of the electrodes was extended from 8.0 min to 78.2 h (500 mA/cm2); although the NB degradation rate decreased from 94.1 to 80.6%, the total amount of theoretical catalytic degradation of NB in the effective working time increased from 17.4 to 8754.1 mg/cm2. These findings reveal good application potential for the electrodes and provide a reference for developing efficient and stable electrode materials.

Flexible, Transparent, and Cytocompatible Nanostructured Indium Tin Oxide Thin Films for Bio-optoelectronic Applications.

Electrical stimulation has been used successfully for several decades for the treatment of neurodegenerative disorders, including motor disorders, pain, and psychiatric disorders. These technologies typically rely on the modulation of neural activity through the focused delivery of electrical pulses. Recent research, however, has shown that electrically triggered neuromodulation can be further enhanced when coupled with optical stimulation, an approach that can benefit from the development of novel electrode materials that combine transparency with excellent electrochemical and biological performance. In this study, we describe an electrochemically modified, nanostructured indium tin oxide/poly(ethylene terephthalate) (ITO/PET) surface as a flexible, transparent, and cytocompatible electrode material. Electrochemical oxidation and reduction of ITO/PET electrodes in the presence of an ionic liquid based on d-glucopyranoside and bistriflamide units were performed, and the electrochemical behavior, conductivity, capacitance, charge transport processes, surface morphology, optical properties, and cytocompatibility were assessed in vitro. It has been shown that under selected conditions, electrochemically modified ITO/PET films remained transparent and highly conductive and were able to enhance neural cell survival and neurite outgrowth. Consequently, electrochemical modification of ITO/PET electrodes in the presence of an ionic liquid is introduced as an effective approach for tailoring the properties of ITO for advanced bio-optoelectronic applications.

Preparation of Yb-Sb co-doped Ti/SnO2 electrode for electrocatalytic degradation of sulfamethoxazole (SMX).

To efficiently break down residual sulfonamide antibiotics in environmental water, Yb-Sb co-doped Ti/SnO2 electrodes were fabricated using a solvothermal method. The effect of different amounts of Yb doping on the properties of the electrodes was studied. When the atom ratio of Sn: Yb is 100 : 7.5 in the preparation, the as-obtained coral-like electrodes (denoted as Yb 7.5%) possessed the smallest diameter of spherical particles on the surfaces, to result in the denser surface, highest electrocatalytic activity and smallest resistance of the electrode. As anode for electrocatalytic degradation of sulfamethoxazole, the Yb 7.5% electrode showed a degradation rate of 92% in 90 min, which was much higher than that of Yb 0% electrode (62.7% degradation rate). The electrocatalytic degradation of sulfamethoxazole was investigated with varying current densities and initial concentrations. Results indicated that the degradation process followed pseudo-first-order kinetics, and the degradation rate constants for Yb 7.5% and Yb 0% electrodes were 0.0278 min-1 and 0.0114 min-1, respectively. Furthermore, the service life of Ti/SnO2 electrodes was significantly improved after Yb doping, as demonstrated by accelerated life testing. Yb 7.5% exhibited a service life that was 2.7 times longer than that of Yb 0%. This work offers a new approach to construct Yb-Sb co-doped Ti/SnO2 electrodes with excellent electrooxidation activity and high stability for the electrochemical oxidation degradation of sulfamethoxazole.

Novel Sb-doped SnO2 ceramic anode coated with a photoactive BiPO4 layer for the photoelectrochemical degradation of an emerging pollutant.

In the present work, a study about the electrochemical and photoelectrochemical degradation of an emerging pollutant using an Sb-doped SnO2 anode coated with a photocatalytic layer of BiPO4 has been performed. The electrochemical characterization of the material was carried out by means of linear sweep voltammetry, light-pulsed chronoamperometry and electrochemical impedance spectroscopy. These studies confirmed that the material is photoactive at intermediate potential values (around 2.5 V), and that the charge transfer resistance decreases in the presence of light. A positive effect of the illuminated area on the degradation degree of norfloxacin was observed: at 15.50 mA cm-2, the degradation rate was 83.37% in the absence of light, 92.24% with an illuminated area of 5.7 cm2, and it increased up to 98.82% with an illuminated area of 11.4 cm2. The kinetics of the process were evaluated, and the by-products of the degradation were identified by ion chromatography and HPLC. In the case of the mineralization degree, the effect of light is less significant, especially at higher current densities. The specific energy consumption of the process was lower in the photoelectrochemical experiments as compared to the experiments in dark conditions. At intermediate current densities (15.50 mA cm-2) a decrease in energy consumption of 53% was achieved by illuminating the electrode.

Oxidative Stress Sensing System for 8-OHdG Detection Based on Plasma Coupled Electrochemistry by Transparent ITO/AuNTAs/PtNPs Electrode.

8-Hydroxydeoxyguanosine (8-OHdG) is the most widely used oxidative stress biomarker of the free radical-induced oxidative damage product of DNA, which may allow a premature assessment of various diseases. This paper designs a label-free, portable biosensor device to directly detect 8-OHdG by plasma-coupled electrochemistry on a transparent and conductive indium tin oxide (ITO) electrode. We reported a flexible printed ITO electrode made from particle-free silver and carbon inks. After inkjet printing, the working electrode was sequentially assembled by gold nanotriangles (AuNTAs) and platinum nanoparticles (PtNPs). This nanomaterial-modified portable biosensor showed excellent electrochemical performance for 8-OHdG detection from 10 µg/mL to 100 µg/mL by our self-developed constant voltage source integrated circuit system. This work demonstrated a portable biosensor for simultaneously integrating nanostructure, electroconductivity, and biocompatibility to construct advanced biosensors for oxidative damage biomarkers. The proposed nanomaterial-modified ITO-based electrochemical portable device was a potential biosensor to approach 8-OHdG point-of-care testing (POCT) in various biological fluid samples, such as saliva and urine samples.

Ecofriendly sol-gel-derived dye-sensitized solar cells with aluminium-doped tin oxide photoanode.

The manuscript reports the fabrication of an eco-friendly sol gel dye-sensitized solar cell (DSSC) based on aluminium (Al)-doped tin oxide nanoparticles with different concentrations (0.5, 1, and 5 mol%) of Al providing enhanced optical and electrical properties than its bare counterparts. The physical, chemical, optical, and electrical properties of the as-synthesized nanoparticles were studied using different analytical tools. X-ray diffraction (XRD) study reveals the crystal structure of the prepared samples ascribed to SnO2 nanoparticles uniformly with reduced crystallite size for Al-doped SnO2 nanoparticles. Field emission scanning electron microscope (FESEM) analysis reveals narrowing of particle size on doping with the Al, substantially enhancing the optical and surface characteristic features of the SnO2 nanoparticles. Photoconductivity studies indicate that all the samples have a good linear response with the increment of electric field in dark and photocurrent attributing to better photoconversion capability of the samples. Further, the optimized Al-doped SnO2 and bare SnO2 nanoparticles were subjected to sophisticated analytical studies such as high-resolution transmission electron microscope (HR-TEM) and X-ray photoelectron spectroscopy (XPS) for the better insight into their properties. The as-prepared Al-doped SnO2 nanoparticles in the present study record good optical, surface, and electrical properties which enhance their compatibility for possible photovoltaic applications especially in dye-sensitized solar cells as an environmentally safe alternate energy solution. Further, the current density-voltage (J-V) characteristics of the optimized Al-SnO2 and bare SnO2 photoanode component were probed for their suitability in DSSCs which disclosed enriched efficiency upon doping with aluminium nanoparticles.

Fabrication of a SnO2-Sb electrode with TiO2 nanotube array as the middle layer for efficient electrochemical oxidation of amaranth dye.

Efficient, stable, and easily producible electrodes are useful for treating dye wastewater through electrochemical oxidation. In this study, an Sb-doped SnO2 electrode with TiO2 nanotubes as the middle layer (TiO2-NTs/SnO2-Sb) was prepared through an optimized electrodeposition process. Analyses of the coating morphology, crystal structure, chemical state, and electrochemical properties revealed that tightly packed TiO2 clusters provided a larger surface area and more contact points, which is conducive to reinforcing the binding of SnO2-Sb coatings. Compared with a Ti/SnO2-Sb electrode without a TiO2-NT interlayer, the catalytic activity and stability of the TiO2-NTs/SnO2-Sb electrode significantly improved (P < 0.05), as reflected by the 21.8% increase in the amaranth dye decolorization efficiency and 200% increase in the service life. The effects of current density, pH, electrolyte concentration, initial amaranth concentration, and the interaction between various combinations of parameters on the electrolysis performance were investigated. Based on response surface optimization, the maximum decolorization efficiency of the amaranth dye could reach 96.2% within 120 min under the following set of optimized parameter values: 50 mg L-1 amaranth concentration, 20 mA cm-2 current density, and 5.0 pH. A potential degradation mechanism of the amaranth dye was proposed based on the experimental results of a quenching test, ultraviolet-visible spectroscopy, and high-performance liquid chromatography-mass spectrometry. This study provides a more sustainable method for fabricating SnO2-Sb electrodes with TiO2-NT interlayers to treat refractory dye wastewater.

Natural sunlight driven photocatalytic dye degradation by biogenically synthesized tin oxide (SnO2) nanostructures using Tinospora crispa stem extract and its anticancer and antibacterial applications.

In the present study, tin oxide (SnO2) was synthesized by advocating the principles of green chemistry for the photo-mediated degradation of pollutants, antimicrobial, and as an antitumor agent. Bioactive SnO2 (nanorods & nanospheres) were fabricated using Tinospora crispa stem extract (TCSE) via sol-gel technique and characterized extensively. XRD, UV-VIS, FTIR, and XPS studies confirmed the formation of crystalline and well stoichiometric pure phase of SnO2 nanostructures with optical bandgap 3.2 to 3.5 eV. The transmission electron microscopy (TEM) results demonstrated the effect of secondary phytoconstituents on the shape of SnO2 in a concentration dependent manner. The morphological variations in the obtained nanostructures attributed to the nucleation density and coalescence effect leading to the formation of nanorods with an average diameter 23-25 nm whereas the average particle size of the nanospheres obtained was found to be 23-30 nm. The zeta potential value of SnO2 nanorods was high (- 58.9 mV) indicating the higher stability compared to nanospheres (- 15.6 mV). The SnO2 nanostructures were investigated for the simultaneous degradation of methylene blue with degradation efficiency of 92.3% and 47.3% for rhodamine B in mono system and 72.3%, 47.7% respectively for binary dye system. The anticancer activity of SnO2 nanorods explored against human breast cancer (MCF-7) cells revealed a concentration dependent cytotoxic effect reactive oxygen species (ROS) induced cell death. Additionally, efficient antibacterial activity of SnO2 was established using E.coli. Multifaceted applications of Tinospora crispa stem extract mediated SnO2 nanostructures.

Highly Sensing and Selective Performance Based on Bi-Doped Porous ZnSnO3 Nanospheres for Detection of n-Butanol.

In this study, pure zinc stannate (ZnSnO3) and bismuth (Bi)-doped ZnSnO3 composites (Bi-ZnSnO3) were synthesized via the in situ precipitation method, and their microstructures, morphologies, chemical components, sizes, and specific surface areas were characterized, followed by testing their gas sensing properties. The results revealed that Bi-ZnSnO3 showed superior gas sensing properties to n-butanol gas, with an optimal operating temperature of 300 °C, which was 50 °C lower than that of pure ZnSnO3. At this temperature, moreover, the sensitivity of Bi-ZnSnO3 to n-butanol gas at the concentration of 100 ppm reached as high as 1450.65, which was 35.57 times that (41.01) of ammonia gas, 2.93 times that (495.09) of acetone gas, 6.02 times that (241.05) of methanol gas, 2.54 times that (571.48) of formaldehyde gas, and 2.98 times that (486.58) of ethanol gas. Bi-ZnSnO3 had a highly repeatable performance. The total proportion of oxygen vacancies and chemi-adsorbed oxygen in Bi-ZnSnO3 (4 wt%) was 27.72% to 32.68% higher than that of pure ZnSnO3. Therefore, Bi-ZnSnO3 has considerable potential in detecting n-butanol gas by virtue of its excellent gas-sensing properties.