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K Anitha

Publications and source records attributed to K Anitha.

4 recordsLinked to original sources
PubMed2006

L-prolinium picrate and 2-methylpyridinium picrate.

In the structure of L-prolinium picrate, C5H10NO2+.C6H2N3O7-, the Cgamma atom of the pyrrolidine ring has conformational disorder. Both the major and minor conformers of the pyrrolidine ring adopt conformations intermediate between a half-chair and an envelope. Both the cation and anion are packed through chelated three-centred N-H...O hydrogen bonds. The prolinium cation connects two different picrate anions, leading to an infinite chain running along the b axis. In 2-methylpyridinium picrate, C6H8N+.C6H2N3O7-, the cations and anions are packed separately along the a axis and are interconnected by N-H...O hydrogen bonds. Intramolecular contacts between phenolate O atoms and adjacent nitro groups are identified in both structures. A graph-set motif of R1(2)(6) is observed in both structures.

Journal Article↗
PubMed2006

Pyridoxinium picrate.

The title compound [systematic name: 3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridinium 2,4,6-trinitrophenolate], C(8)H(12)NO(3)(+)xC(6)H(2)N(3)O(7)(-), is a complex of picric acid with pyridoxine. The asymmetric part of the unit cell contains one pyridoxinium cation and one picrate anion. The aromatic rings of the picrate anion and the pyridoxinium cation are inclined with a dihedral angle of 83.19 (7) degrees . An intramolecular hydrogen bond between OH and a nearby CH(2)OH group is observed in the cation. The hydrophobic layers at y = {1/2} are packed between the hydrophilic layers at y = 0.

Anions↗
PubMed2004

Development of acetylcholinesterase silica sol-gel immobilized biosensor--an application towards oxydemeton methyl detection.

An amperometric silica sol-gel film immobilized biosensor doped with acetylcholinesterase was fabricated in the laboratory finding application in organophosphate detection based on enzyme inhibition. The substrate used was acetylthiocholine chloride and thiocholine released from the enzymatic hydrolysis was electrochemically oxidized giving larger anodic current at 0.5-0.6 V (versus Ag/AgCl reference). The dependencies of the current response on pH, enzyme loading and thermal stability of the developed biosensor were evaluated. The analytical performance of enzyme electrode towards substrate and inhibitor was investigated. Oxydemeton methyl was taken as a model compound for the inhibition studies. Linear calibration for oxydemeton methyl was obtained in the range of 2-200 ppb under the optimized conditions following an incubation time of 20 min. Treatment of the inhibited enzyme with pyridine-2-aldehyde restored 92% of its original activity. The sensor stored at -20 degrees C had a good storage and operational stability retaining 85% of its original activity for 60 successive measurements.

Acetylcholinesterase↗