Evaluation of nanoparticle fabrication for improved localized surface plasmon resonance response

¹ *Council for Scientific and Industrial Research, National Laser Centre, Pretoria, South Africa.
² Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, South Africa.
³ School of Interdisciplinary Research and Graduate Studies (UNESCO), College of Graduate Studies, University of South Africa, Preller Street, Muckleneuk Ridge, Pretoria

Abstract

Due to their versatility, gold nanoparticles are becoming more popular in biosensing applications. Some of the advantages include the use of fabrication, inexpensive, and highly compatible with portable point-of- care medical diagnostics. The fabrication of nanoparticles is usually straightforward and can be easily performed in low-cost settings. In biosensing, light interacting with nanoparticles produces a collective oscillation of electrons known as the localized surface plasmon resonance (LSPR). However, noble nanoparticles in LSPR-based biosensors have limitations including The limit of detection and sensitivity remain the two major challenges. In this study, gold nanoparticles were immobilized through a butanol-induced self-assembly process to improve sensitivity. In this approach, in DNA hybridization experiment we increased LSPR peak shifts, using simulation data sets, from 0.005 nm to 0.3 nm. We detected complementary hybridization between a target DNA and a capture probe, and partial complementary hybridization between a target DNA and a capture probe. The data acquired from the study suggests that the nanoparticle immobilization through a butanol-induced approach resulted in the in-house built LSPR system’s increased sensitivity in detecting nano- scale biological hybridization. This study will contribute to developing a point-of-care HIV-1 drug-resistance mutation detection device.