Chitosan-nickel film based interferometric optical fiber sensor for label-free detection of histidine tagged proteins.

Author(s) Ravikumar, R.; Chen, L.Han; Jayaraman, P.; Poh, C.Loo; Chan, C.Chiu
Journal Biosens Bioelectron
Date Published 2018 Jan 15
Abstract

An interferometric fiber sensor for detection of hexa-histidine tagged microcin (His-MccS) is reported and experimentally demonstrated. This intermodal fiber sensor is implemented by a no-core fiber (NCF) functionalized with chitosan (CS)-nickel (Ni) film for direct detection of small peptide: microcin. The fiber intermodal sensor relies on the refractive index modulations due to selective adsorption event at the chitosan (CS)-nickel (Ni) film. Owing to the strong affinity between Ni2+ ions and histidine, the immobilized Ni2+ ions in the chitosan film were utilized as binding agents for the direct detection of hexa-histidine tagged microcin. A comparative study in relation to different target size was conducted: full proteins trypsin, bovine serum albumin (BSA) and human serum albumin (HSA), with high histidine content on their surface and His-MccS (peptide, 11.6kDa), have been employed for sensor evaluation. Results have shown selectivity for His-MccS relative to trypsin, BSA and HSA. The most telling contribution of this study is the fast detection of small biomolecule His-MccS compared to standard detection procedures like SDS-PAGE and western blot. The proposed sensor exhibits His-MccS detection sensitivity of 0.0308nm/(ng/ml) in the range of (0-78) ng/ml with concentration detection limit of 0.8368ng/ml.

DOI 10.1016/j.bios.2017.08.012
ISSN 1873-4235
Citation Ravikumar R, Chen LH, Jayaraman P, Poh CL, Chan CC. Chitosan-nickel film based interferometric optical fiber sensor for label-free detection of histidine tagged proteins. Biosens Bioelectron. 2018;99:578-585.