Emergence and expansion of highly infectious spike protein D614G mutant SARS-CoV-2 in central India.

COVID-19 has emerged as global pandemic with largest damage to the public health, economy and human psyche.The genome sequence data obtained during the ongoing pandemic are valuable to understand the virus evolutionary patterns and spread across the globe. Increased availability of genome information of circulating SARS-CoV-2 strains in India will enable the scientific community to understand the emergence of new variants and their impact on human health.

Gas chromatography-mass spectrometric identification of cyanide using a nucleophilic substitution based derivatization with -phenyl benzenethiosulfonate.

A novel, simple and efficient analytical method for GC-MS based identification of cyanide has been developed using a single step nucleophilic substitution based derivatization of cyanide in aqueous medium. The nucleophilic substitution reaction of cyanide with S-phenyl benzenethiosulfonate results in the formation of phenyl thiocyanate as a cyanide derivative and it was found that the relative response of the resultant cyanide derivative was much higher than that of the cyanide derivatives resulting from disulfide based derivatizing agents. The sample preparation protocol for the identification of cyanide in aqueous samples was also optimized with the new derivatizing agent.

Development of magnetic bead based sample extraction coupled polymerase spiral reaction for rapid on-site detection of Chikungunya virus.

The molecular detection system has evolved over last two decades and is rapidly replacing the conventional confirmatory techniques in diagnostic virology. However the major limitation in implementation of available molecular detection assays is the non availability of field deployable nucleic acid isolation platform coupled with gene amplification technique. The rapid and early molecular detection is crucial for employing effective measure against many viral infections.

Triazine-Based Covalent Organic Framework: A Promising Sorbent for Efficient Elimination of the Hydrocarbon Backgrounds of Organic Sample for GC-MS and H NMR Analysis of Chemical Weapons Convention Related Compounds.

The strict monitoring and precise measurements of chemical warfare agents (CWAs) in environmental and other complex samples with high accuracy have great practical significance from the forensic and Chemical Weapons Convention (CWC) verification point of view. Therefore, this study was aimed to develop an efficient extraction and enrichment method for identification and quantification of toxic agents, especially with high sensitivity and multidetection ability in complex samples. It is the first study on solid-phase extraction (SPE) of CWAs and their related compounds from hydrocarbon backgrounds using covalent triazine-based frameworks (CTFs).

Efficient Extraction of Sulfur and Nitrogen Mustards from Nonpolar Matrix and an Investigation on Their Sorption Behavior on Silica.

Extraction of vesicant class of chemical warfare agents (CWAs) such as sulfur mustard and nitrogen mustards from the environmental matrices is of prime importance, from a forensic and verification viewpoint of the Chemical Weapons Convention (CWC). For extraction of Convention Related Compounds from nonpolar organic medium, commercially available silica cartridges are used extensively, but silica cartridges exhibit limited efficiency toward vesicant classes of compounds. It is expected that sulfur mustard being nonpolar does not retain sufficiently on silica surface, and nitrogen mustards (being basic) are strongly adsorbed on acidic silica surface, resulting in their poor recoveries.

Polymeric Sorbent with Controlled Surface Polarity: An Alternate for Solid-Phase Extraction of Nerve Agents and Their Markers from Organic Matrix.

Extraction and identification of lethal nerve agents and their markers in complex organic background have a prime importance from the forensic and verification viewpoint of the Chemical Weapons Convention (CWC). Liquid-liquid extraction with acetonitrile and commercially available solid phase silica cartridges are extensively used for this purpose. Silica cartridges exhibit limited applicability for relatively polar analytes, and acetonitrile extraction shows limited efficacy toward relatively nonpolar analytes.

Analysis of chemical warfare agents in organic liquid samples with magnetic dispersive solid phase extraction and gas chromatography mass spectrometry for verification of the chemical weapons convention.

A simple, sensitive and low temperature sample preparation method is developed for detection and identification of Chemical Warfare Agents (CWAs) and scheduled esters in organic liquid using magnetic dispersive solid phase extraction (MDSPE) followed by gas chromatography-mass spectrometry analysis. The method utilizes Iron oxide@Poly(methacrylic acid-co-ethylene glycol dimethacrylate) resin (Fe2O3@Poly(MAA-co-EGDMA)) as sorbent. Variants of these sorbents were prepared by precipitation polymerization of methacrylic acid-co-ethylene glycol dimethacrylate (MAA-co-EGDMA) onto Fe2O3 nanoparticles.

Magnetic hydrophilic-lipophilic balance sorbent for efficient extraction of chemical warfare agents from water samples.

Magnetic hydrophilic-lipophilic balance (MHLB) hybrid resin was prepared by precipitation polymerization using N-vinylpyrrolidone (PVP) and divinylbenzene (DVB) as monomers and Fe2O3 nanoparticles as magnetic material. These resins were successfully applied for the extraction of chemical warfare agents (CWAs) and their markers from water samples through magnetic dispersive solid-phase extraction (MDSPE). By varying the ratios of monomers, resin with desired hydrophilic-lipophilic balance was prepared for the extraction of CWAs and related esters of varying polarities.

Method for Derivatization and Detection of Chemical Weapons Convention Related Sulfur Chlorides via Electrophilic Addition with 3-Hexyne.

Sulfur monochloride (S2Cl2) and sulfur dichloride (SCl2) are important precursors of the extremely toxic chemical warfare agent sulfur mustard and classified, respectively, into schedule 3.B.12 and 3.

Single vial sample preparation of markers of nerve agents by dispersive solid-phase extraction using magnetic strong anion exchange resins.

A sample preparation method involving extraction, enrichment and derivatization of acidic degradation products of nerve agents was developed using magnetic strong anion exchange resins (MSAX). The method was performed in a single vial involving magnetic dispersive solid phase extraction (MDSPE). Analytes were derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) in the presence of resins.

A highly selective and sensitive "turn-on" fluorescence chemodosimeter for the detection of mustard gas.

A new chemodosimetric protocol based on a tandem S-alkylation followed by desulfurisation reaction of rhodamine-thioamide with mustard gas is reported. The chemodosimeter is highly selective for potential DNA alkylating agents like sulfur mustard, over other simple alkyl halides with the limit of detection of 4.75 μM.

Extraction and derivatization of chemical weapons convention relevant aminoalcohols on magnetic cation-exchange resins.

Analysis and identification of nitrogen containing aminoalcohols is an integral part of the verification analysis of chemical weapons convention (CWC). This study was aimed to develop extraction and derivatization of aminoalcohols of CWC relevance by using magnetic dispersive solid-phase extraction (MDSPE) in combination with on-resin derivatization (ORD). For this purpose, sulfonated magnetic cation-exchange resins (SMRs) were prepared using magnetite nanoparticles as core, styrene and divinylbenzene as polymer coat and sulfonic acid as acidic cation exchanger.

In vitro reactivation potency of novel symmetrical bis-pyridinium oximes for electric eel acetylcholinesterase inhibited by nerve agent sarin.

This communication describes synthesis and in vitro evaluation of a series of novel bis-pyridinium oximes connected by bis-methoxymethyl benzene, 1,4-bis-methoxymethyl (cis)-but-2-ene and 1,4-bis-methoxymethyl but-2-yne linkers as reactivators of sarin inhibited acetylcholinesterase (AChE). The reactivation data of synthesized oximes were compared with those of 2-PAM and obidoxime. The efficacy of oximes such as 1,4-dimethoxy cis-but-2-ene bis-[4,4'-(hydroxyiminomethyl)-pyridinium] dichloride (3g), 1,4-dimethoxy benzene bis-[3,3'-(hydroxyimino-methyl) pyridinium] dichloride (3b) and 1,3-dimethoxy benzene bis-[3,3'-(hydroxy-iminomethyl) pyridinium] dichloride (3e) were found to be more than that of obidoxime in reactivating sarin inhibited AChE.

In vitro reactivation of sarin-inhibited human acetylcholinesterase (AChE) by bis-pyridinium oximes connected by xylene linkers.

A series of bis-pyridinium oximes connected by xylene linkers were synthesized and their in vitro reactivation potential was evaluated against human acetylcholinesterase (hAChE) inhibited by nerve agent sarin and the data were compared with 2-PAM and obidoxime. Among the synthesized compounds, N,N'-p-xylene-bis-[(2,2'-hydroxyiminomethyl)pyridinium] dibromide (3c) was found to be the most potent reactivator for hAChE inhibited by sarin. The oxime 3c exhibited 45% regeneration of inhibited hAChE, in comparison to 34% and 24% regeneration by 2-PAM and obidoxime, respectively, at a concentration of 10(-3) M within 10 min.

In vitro evaluation of bis-pyridinium oximes bearing methoxy alkane linker as reactivators of sarin inhibited human acetylcholinesterase.

A series of bis-pyridinium oximes connected by methoxy alkane linkers were synthesized and their in vitro reactivation efficacy was evaluated against sarin-inhibited human AChE, and data were compared with 2-PAM and obidoxime. Among the synthesized compounds, 1,2-dimethoxy ethylene bis-[4,4'-(hydroxyiminomethyl) pyridinium] dichloride (4P-2) and 1,2-dimethoxy ethylene bis-[3,3'-(hydroxyiminomethyl) pyridinium] dichloride (3P-2) were found to be the most potent reactivators of human AChE inhibited by nerve agent sarin. The oximes 4P-2 and 3P-2 exhibited 41% and 36% regeneration of sarin-inhibited AChE, respectively, whereas 2-PAM showed 32% regeneration.

In-vitro regeneration of sarin inhibited electric eel acetylcholinesterase by bis-pyridinium oximes bearing xylene linker.

A series of bis-pyridinium oximes connected by xylene linker were synthesized and their in-vitro reactivation potential was evaluated against acetylcholinesterase (AChE) inhibited by nerve agent, sarin. Among the synthesized compounds, alpha,alpha'xylene-bis-[3,3'-(hydroxyiminomethyl) pyridinium] dibromide (3b) was found to be most potent reactivator for AChE inhibited by sarin. The oxime 3b exhibits 34% regeneration of inhibited AChE, in comparison to 20 and 15% regeneration by 2-PAM and obidoxime, respectively, at a concentration of 10(-4) M within 10 min.

Synthesis and evaluation of novel bis-pyridinium oximes as reactivators of DFP-inhibited acetylcholinesterase.

A series of novel bis-pyridinium oximes connected by bis-methoxymethyl benzene, 1,4-bis-methoxymethyl (cis)-but-2-ene and 1,4-bis-methoxymethyl but-2-yne linkers were synthesized and their in vitro reactivation efficacy was evaluated against diisopropyl phosphorofluoridate (DFP) inhibited acetylcholinesterase (AChE) and compared with the established antidote 2-PAM and obidoxime. However, the best reactivation was observed with the standard oxime 2-PAM. The reactivation efficacy of 1,3-dimethoxymethyl benzene bis-[4,4'-(hydroxyiminomethyl) pyridinium] dichloride (3d) and 1,4-dimethoxy but-2-ene bis-[4,4'-(hydroxyiminomethyl) pyridinium] dichloride (3g) was comparable with that of obidoxime, another standard antidote.

In vitro reactivation of sarin inhibited electric eel acetylcholinesterase by bis-pyridinium oximes bearing methoxy ether linkages.

Bis-pyridinium oximes connected by methoxy alkane ether linker were synthesized and their in vitro reactivation efficacy was evaluated for sarin inhibited AChE. Reactivation efficacy of synthesized compounds was compared with 2-PAM and obidoxime. Among the synthesized compounds, 1,2-dimethoxy ethylene bis-[3,3'-(hydroxyiminomethyl) pyridinium] dichloride (3P-2) and 1,3-dimethoxy propylene bis-[3,3'-(hydroxyiminomethyl) pyridinium] dichloride (3P-3) were found to be most potent reactivators for AChE inhibited by nerve agent sarin.

Use of single-drop microextraction for determination of fentanyl in water samples.

Fentanyl is a very potent synthetic narcotic analgesic. Because of its strong sedative properties, it has become an analogue of illicit drugs such as heroin. Its unambiguous detection and identification in environmental samples can be regarded as strong evidence of its illicit preparation.