Kien Voon Kong, Chris Jun Hui Ho, Tianxun Gong, Weber Kam On Lau, Malini Olivo, Sensitive SERS glucose sensing in biological media using alkyne functionalized boronic acid on planar substrates, Biosensors and Bioelectronics, Volume 56, 15 June 2014, Pages 186-191, ISSN 0956-5663, http://dx.doi.org/10.1016/j.bios.2013.12.062. (http://www.sciencedirect.com/science/article/pii/S0956566313009445) Keywords: Surface-enhanced Raman spectroscopy; Alkyne; Boronic acid; Glucose; Biosensing
Abstract:
In this work, we propose a novel glucose binding mechanism on a highly sensitive SERS substrate, inorder to overcome challenges in specific glucose detection in biofluids. We make use of phenyl boronic acid as a receptor for saccharide capture onto the substrate and the ability of the captured glucose molecule to undergo secondary binding with analkyne-functionalized boronicacid to form a glucose–alkyne–boronic acid complex. The formation of this complex shows high selectivity for glucose,over other saccharides.
In addition,the alkyne group of the alkyne functionalized boronic acid exhibits a distinct Raman peak at1996cm 1 in a biological silent region(1800–2800 cm 1) where most endogenous molecules, including glucose, show no Raman scattering, thus offering a high sensitivity over other SERS glucoses ensing.The substrate offers long-term stability, as well as high SERS enhancement to the glucose–alkyne boronic
acid complex on substrate. In addition, the reversibility of SERS signals at various incubation stages also shows reusability capabilities, where as positive results in clinical urine samples demonstrate clinical feasibility. All these strongly suggest that this newly developed SERS-based assayoffersgreat potential in glucose sensing.