Showing papers by "Anju Chadha published in 2014"
TL;DR: The results obtained in this study could have implications in the design of nanobiomaterials, biosafety concerns and their cellular responses, and the electrostatic and covalent binding of the prepared silica capped gold nanostructures to BSA.
Abstract: This paper presents a detailed and systematic study of amine functionalization of silica coating of gold nanostructures and the electrostatic and covalent binding of the prepared silica capped gold nanostructures to BSA. The involvement of a Tryptophan residue in the hydrophobic pocket of BSA and its interaction with nanostructures was established. Fluorescence studies of tryptophan residues of the protein molecules after conjugation revealed that the method of crosslinking did not bring about major changes to the binding constant (1012 M−1) of BSA to nanostructures. Electrostatic binding indicated a larger number of binding sites (2.56) on the protein. Nanoparticle binding brought about a reduction in the characteristic negative ellipticity of BSA, indicating a change in the helical content. The reduction in the elliptical path of BSA was influenced by both nanoparticle curvature and crosslinker, such as in the case of glutaraldehyde or by the nanoparticle curvature alone as in the case of zero length crosslinker – EDC–NHS. Though not a subject matter of this study, the results obtained in this study could have implications in the design of nanobiomaterials, biosafety concerns and their cellular responses.
27 citations
TL;DR: In this article, the authors have developed a complete triglyceride biochip wherein the enzyme for hydrolysis and the counter electrode for signal transduction are integrated with a miniaturized EISCAP sensor.
Abstract: This paper reports on the design and fabrication of electrolyte insulator semiconductor capacitor (EISCAP) devices to detect triglycerides in the form of microreactors fabricated by bulk micromachining of silicon. We have developed a complete triglyceride biochip wherein the enzyme for hydrolysis and the counter electrode for signal transduction are integrated with a miniaturised EISCAP sensor. A compact readout system that measures the triglyceride concentration in blood serum under test has been developed and is implemented in a Programmable System on Chip (PSoC®). The miniaturised EISCAP devices are tested using blood serum samples to estimate the triglyceride concentration within the clinical range of 50 to 150 mg dL−1 and the time taken by the readout system to calibrate the sensor and to measure the triglyceride is less than 5 minutes.
13 citations
TL;DR: Optically pure allylic alcohols and 4-phenylbutan-2-ols were prepared by oxidative kinetic resolution using whole cells of Candida parapsilosis ATCC 7330 by selectively oxidizing to the corresponding keto compound leaving the ‘R’ alcohol.
Abstract: Optically pure allylic alcohols and 4-phenylbutan-2-ols were prepared by oxidative kinetic resolution using whole cells of Candida parapsilosis ATCC 7330. Only the ‘S’ enantiomer is selectively oxidized to the corresponding keto compound (yield, 37–46%) leaving the ‘R’ alcohol (yield, 37–52% and ee 46 to >99%). The biocatalytic method is carried out under mild conditions at 20 °C, pH 6.5 in phosphate buffer.
10 citations
TL;DR: Optically pure propargyl alcohol thus obtained was used as a chiral starting material in the synthesis of enantiomerically enriched poly-substituted pyrrolidines and a pyrrole derivative successfully demonstrating a chemoenzymatic route.
Abstract: Various aryl and alkyl substituted optically pure propargyl alcohols were obtained with excellent ee (up to >99%) and isolated yields (up to 87%) by deracemization using whole cells of Candida parapsilosis ATCC 7330. The whole cells show substrate specificity towards alkyl substituted propargyl alcohols and a switch in the enantioselectivity has been observed from ‘R’ to ‘S’ upon increasing the chain length. For the first time, enantiopure (R)-4-(3-hydroxybut-1-ynyl)benzonitrile, (R)-4-(biphenyl-4-yl)but-3-yn-2-ol, (S)-ethyl 3-hydroxy-5-phenylpent-4-ynoate and (S)-4-phenylbut-3-yne-1,2-diol were obtained using this strategy. Optically pure propargyl alcohol thus obtained was used as a chiral starting material in the synthesis of enantiomerically enriched poly-substituted pyrrolidines and a pyrrole derivative successfully demonstrating a chemoenzymatic route.
10 citations
TL;DR: This is the first report of the regio- and enantio-selective oxidation of diols using C. parapsilosis ATCC 7330, where the secondary alcohol was preferentially oxidized.
Abstract: Selectivity between primary and secondary alcohols was observed in oxidation using whole cells of Candida parapsilosis ATCC 7330, where the secondary alcohol was preferentially oxidized In racemic sec alcohols, the ‘R’ enantiomer was selectively oxidized to the corresponding keto alcohol (yield = 18–54%) leaving the ‘S’ diol (yield = 31–69% and enantiomeric excess from 14% to >99%) A biphasic system consisting of isooctane–water (48 : 2 v/v) was used as a medium for biotransformation at 25 °C This is the first report of the regio- and enantio-selective oxidation of diols using C parapsilosis ATCC 7330
9 citations
TL;DR: A reversal in solvatochromic behaviour was observed in second and third generation glycerol based dansylated polyether dendrons in water on addition of a second solvent like methanol or acetonitrile.
3 citations
TL;DR: In this article, the same authors used whole cells of Candida parapsilosis ATCC 7330 to extract allylic alcohols and 4-phenylbutan-2-ols.
Abstract: Optically pure allylic alcohols and 4-phenylbutan-2-ols were prepared by oxidative kinetic resolution using whole cells of Candida parapsilosis ATCC 7330. Only the ‘S’ enantiomer is selectively oxidized to the corresponding keto compound (yield, 37–46%) leaving the ‘R’ alcohol (yield, 37–52% and ee 46 to >99%). The biocatalytic method is carried out under mild conditions at 20 °C, pH 6.5 in phosphate buffer.
1 citations