Calmodulin Functionalized Porous Silicon Based Electrical Calcium Detector and its Comparison with Optical Detector

Abstract In this work a bi-parametric, highly selective, electrical calcium detecting platform is fabricated. The fabricated detector consists of porous silicon substrate which is surface functionalized by calmodulin. The use of porous silicon provides many fold increment in surface area, facilitating effective absorption, whereas, calmodulin functionalization upon the porous surface provides excellent calcium attachment sites. The electrical parameters of this detecting platform are then tested with calcium and several other ionic solutions, at concentration relevant physiologically. The fabricated detector showed tremendous selectivity towards calcium ion. Even in mixture ionic solution the detector exhibited its high discrimination towards calcium ion. Thus the fabricated detecting platform can work as an effective calcium detector. Its bi-parametric approach provides enhanced calcium detection efficiency. Hence the detector imparts a highly selective, robust, label free and cost-effective alternative for calcium detectors, effective even in biologically relevant concentrations. Later a comparative study is performed between the optical and electrical response of the detector platform to provide a better understanding of the consistency of the detector developed that in future will facilitate multi-parametric approach to enhance the response, selectivity and thus the efficiency of the detector platform developed in this work.