Kassegne S.,MEMS Research Laboratory |
Arya B.,MEMS Research Laboratory |
Yadav N.,MEMS Research Laboratory
Sensors and Actuators, B: Chemical | Year: 2010
This study investigates, through numerical modeling, the effects of protonation of histidine buffer in promoting DNA hybridization in electronically active microarrays within a limited pH range. The numerical model framework developed in this study consists of a number of physical phenomena (conservation and mass transport of species) and chemical equilibrium reactions (hydrolysis of water, heterogeneous DNA hybridization, and protonation of histidine) that govern the hybridization of single-stranded DNA molecules (ssDNA) in active microarrays within an environment of continuous generation of H+ ions and their subsequent consumption by histidine buffer. The study demonstrates, through a numerical model and comparison with published experimental results, that the increase in acidity near anodes due to the hydrolysis of water can be neutralized by a histidine buffer creating a relatively stable pH environment. To account for the dependency of DNA hybridization on the pH of the buffer used, the study also introduces a new hybridization efficiency parameter into the numerical model that is based on experimental data for DNA hybridization. © 2009 Elsevier B.V. All rights reserved.
Pudasaini P.R.,MEMS Research Laboratory |
Ayon A.A.,MEMS Research Laboratory
Microsystem Technologies | Year: 2013
We report the computational modeling of the front side plasmonics effect arising on gold (Au) nanoparticles array in combination with nanotextured silicon surface for thin film silicon solar cells application. The ultimate efficiency of the optimized silicon nanoholes (SiNH) array textured surface using Au plasmonics effect is 38.58 %, which is 24.01 % greater than SiNH array textured surface without Au plasmonics effect. Furthermore, SiNH array textured surface perform better compared to silicon nanopillar (SiNP) array textured surface for all the parameters studied. The maximum possible short circuit current density and power conversion efficiency of the proposed SiNH array textured surface with Au plasmonics effect are 31.57 mA/cm2 and 25.45 % respectively, which compares favorably well to the computed values of 26.17 mA/cm2 and 21.12 %, respectively for the SiNP array textured surface with Au plasmonics effect. © 2013 Springer-Verlag Berlin Heidelberg.