Growth and characterizations of bis glycine hydrogen bromide (BGHB) single crystal: new nonlinear optical material

Growth and characterization of new nonlinear optical material bis glycine hydrogen bromide is reported in the present communication. Single crystals of bis glycine hydrogen bromide was grown from solution by slow evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction analysis, to confirm the crystal structure and to measure cell parameters. The presence of functional groups and coordination of glycine group with hydro bromic acid were confirmed by FTIR, UV-visible and absorbance spectrum was recorded to study the transparency of grown crystals. The bis glycine hydrogen bromide crystal does not decompose before melting. This was confirmed by thermo gravimetric analysis (TGA). The second order nonlinear optical property of the grown crystal was confirmed by Kurtz and Perry powder SHG test.Â

Effect of L-Alanine on the Optical Properties of Zinc (Tris) Thiourea Sulfate (ZTS) Single Crystal

The growth of L-Alanine doped Zinc (tris) Thiourea Sulfate single crystal from aqueous solution by low temperature solution growth has been reported in the present investigation. The 1, 2 and 3mole% L-Alanine was doped in saturated ZTS solution. The effect of L-Alanine on SHG property was studied by Kurtz and Perry powder SHG test. The higher enhancement in SHG efficiency was observed at 1mole% L-Alanine doped ZTS. Hence, the growth 1mole% L-Alanine doped ZTS was carried. The grown crystal was characterized by single crystal X-ray analysis, FT-IR, UV-visible spectroscopy and thermal study by TGA and DSC analysis

Ammonia Gas Sensing Characteristics of Spin Coated Polyaniline Films

The conductive layer of emeraldine base polyaniline (PANI) thin film coated on silicon has successfully tested for ammonia. The bulk PANI powder was synthesized by oxidative polymerization of aniline using ammonium peroxidisulfate in an acidic medium and dissolved in N-methyl pyrrolidone (NMP) for coating the thin film on Silicon using spin coater. FTIR, UVvisible, and SEM were used to characterize the PANI thin film. The electrical conductivity of the PANI films has been studied by measuring the change in electrical conductivity by Four Probe Set up on exposure to ammonia gas (NH3) at different concentrations from 100 ppm to 500 ppm. margin

CRYSTAL ENGINEERING OF ANTIVIRAL AGENT EFAVIRENZ FOR SOLUBILITY ENHANCEMENT

In the current study, we attempted to improve the physicochemical properties of antiviral drug efavirenz through the cocrystal synthesis. The neat grinding performed to study the effect of coformer-fumaric acid (FA) on solubility and dissolution of efavirenz, which can serve as the green cocrystal synthesis approach. The prepared cocrystals were characterized for characteristics like powder flow properties, aqueous saturation solubility, in vitro powder dissolution study. The synthesized cocrystals were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction. The formation of a cocrystal of efavirenz and caffeine was confirmed by the characterization techniques which suggests the interactions between efavirenz and coformer-fumaric acid leads to cocrystal formation. The powder flow properties, solubility, and dissolution profile of efavirenz are significantly improved by its cocrystallization.Â

Nanocomposite Platform Based on EDTA Modified Ppy/SWNTs for the Sensing of Pb(II) Ions by Electrochemical Method

Heavy metal ions are considered as one of the major water pollutants, revealing health hazards as well as threat to the ecosystem. Therefore, investigation of most versatile materials for the sensitive and selective detection of heavy metal ions is need of the hour. Proposed work emphasizes the synthesis of conducting polymer and carbon nanotube nanocomposite modified with chelating ligand for the detection of heavy metal ions. Carbon nanotubes are having well known features such as tuneable conductivity, low density, good charge transport ability, and current carrying capacity. Conducting polymers are the most reliable materials for sensing applications due to their environmental stability and tuning of conductivity by doping and de-doping. Formation of nanocomposite of these two idealistic materials is advantageous over the individual material, which can help to tackle the individual limitations of these materials and can form versatile materials with ideal chemical and electrical properties. Chelating ligands are the most favorable materials due to their ability of complex formation with metal ions. The present work possesses a sensing platform based on conducting polymer and carbon nanotube nanocomposite, which is stable in various aqueous media and possess good charge transfer ability. Chelating ligands played an important role in the increased selectivity toward metal ions. Moreover, in present investigation Ethylenediaminetetraacetic acid (EDTA) functionalized polypyrrole (Ppy) and single walled carbon nanotubes (SWNTs) nanocomposite was successfully synthesized by electrochemical method on stainless steel electrode (SSE). The electrochemical detection of Pb(II) ions using EDTA-Ppy/SWNTs nanocomposite was done from aqueous media. Cyclic voltammetry technique was utilized for the electrochemical synthesis of Ppy/SWNTs nanocomposite. Ppy/SWNTs nanocomposite was further modified with EDTA using dip coating technique at room temperature. The EDTA-Ppy/SWNTs modified stainless steel electrode (SSE) exhibited good sensitivity and selectivity toward heavy metal ions [Pb(II)]. Detection limit achieved for Pb(II) ions was 0.07 μM

Electrochemical Detection of Heavy Metal Ions Based on Nanocomposite Materials

Heavy metal ions (HMIs) have acute toxic effects on health and are dangerous for human existence and the ecosystem. Therefore, their sensitive and selective detection is of great importance. In recent years, various nanocomposite materials have been used by researchers for the detection of HMIs by using various modalities of electrochemical techniques. This review summarizes the recent advances in developing electrochemical sensors based on numerous nanocomposite materials for detecting HMIs. Nanocomposite materials, such as metal–organic frameworks (MOFs), organic conducting polymer (OCPs), carbon nanotubes (CNTs), graphene oxide (GO), graphene/reduced graphene oxide (rGO), graphitic carbon nitride, metal oxide, chitosan, MXenes, metal nanoparticle-based nanocomposites, etc., have been explored by various researchers to improve the sensing properties of electrochemical sensors. This review emphasizes nanocomposite materials’ synthesis and characterization techniques, modalities for HMI detection using electrochemical techniques, and electrochemical sensors. Moreover, this review highlights the development of portable biosensors for detecting HMIs in real-world scenarios, such as environmental monitoring, food safety, and clinical diagnosis. This review also demonstrates the importance of electrochemical sensors based on nanocomposite materials as a reliable, sensitive, and selective tool for detecting HMIs

Ammonia Gas Sensing Characteristics of Chemically Synthesized Polyaniline Matrix

In present investigations polyaniline matrix was synthesized by oxidative polymerization (chemically synthesized). The polyaniline matrix was prepared on Si- substrate. The active layer of PANI as a sensor was fabricated with the help of spin-coating technique. The structural insight into the synthesized polyaniline matrix was sought by Fourier Transform Infrared (FTIR) spectroscopy. The mechanism of formation of polyaniline was also confirmed by UV spectroscopy. The electrical conductivity was measured by four probe method at room temperature. Ammonia gas sensing characteristics of the synthesized polyaniline matrix was studied by measuring the change in electrical resistance on exposure to ammonia gas at different concentrations from 100 to 500 ppm. The polyaniline matrix exhibits excellent sensing behavior for ammonia gas

Development of an Optical Urea Biosensor Using Polypyrrole-polyvinyl Sulphonate Film

Development of an intensity modulated fiber optic PPy-PVS biosensor for the detection of urea has been presented. The sensor design is based on the modified cladding technique. Polypyrrole (PPy) film doped with polyvinyl sulfonate (PVS) was synthesized (by in-situ chemical polymerization at room temperature) with optimized process parameters. The PPy-PVS film provides good porous matrix for the immobilization of enzyme-urease on the sensing probe by cross linking via glutaraldehyde. The characterization of the urea biosensor has been carried out with an indigenously developed sensing chamber and optical fiber test bench. This biosensor showed almost stable and linear response to urea in the range 1-100 mM up to 24 days. It shows very good selectivity and repeatability

Chromium-Modified Lanthanum-Based Metal–Organic Framework: Novel Electrochemical Sensing Platform for Pb(II) Ions

Heavy metal ions (HMIs) in drinking water result from industrialization and can cause a nuisance to the environment. Due to their toxicity and carcinogenic tendencies toward humans, determining HMIs remains challenging. This study focuses on creating a cutting-edge electrochemical sensor with unprecedented sensitivity to lead (Pb(II)). In the present investigation, we have hydrothermally produced lanthanum porous coordination polymer (La-TMA), which was further modified with chromium (Cr) nanoparticles, characterized with structural, morphological, electrochemical, and spectroscopic techniques, and used as a sensing material. The differential pulse voltammogram pattern of the chromium-modified lanthanum porous coordination polymer (Cr@La-TMA) sensor indicates an affinity for Pb(II). Sensing parameters such as sensitivity, selectivity, and linearity have been investigated. The Cr@La-TMA sensor shows selectivity towards Pb(II), which is also validated by the interference study for various analytes such as Cd(II), Hg(II), Cu(II), Cr(II), and Fe(II). The sensor exhibited excellent linearity for the concentration range of 1 nM to 10 nM with a limit of detection of 1 nM, which is below the maximum contamination level (MCL) suggested by the United States Environmental Protection Agency (US-EPA) and World Health Organization (WHO). The proposed sensor would be incredibly useful for the real-time monitoring of heavy metal ions