title: Highly sensitive and selective glucose sensor based on ultraviolet-treated nematic liquid crystals.
abstract: Glucose is an extremely important biomolecule, and the ability to sense it has played a significant role in facilitating the understanding of many biological processes. Here, we report a novel glucose sensor based on ultraviolet (UV)-treated nematic liquid crystals. Submerging UV-treated 4-cyano-4'-pentylbiphenyl (5CB) in a glucose solution (while carefully adjusting its pH to 7.5 with NaOH and HCl) triggered an optical response, from dark to bright, observed with a polarized microscope. Notably, 5CB was located inside a glucose oxidase (GOx)-modified gold grid. We exploited this pH-driven phenomenon to design a new glucose sensor. This device could detect as little as 1 pM analyte, which is 3 orders of magnitude lower than the detection limit of the most sensitive glucose sensor currently available. It also exhibits high selectivity due to GOx modification. Thus, this is a promising technique for glucose detection, not only for clinical diagnostics, but also for sensing low levels of glucose in a biological environment (e.g., single cells and bacterial cultures).
authors.affiliation: Department of Chemistry, Gachon University, Seongnam-Si, Gyeonggi-Do 461-701, Korea.
authors.forename: Shenghong
authors.initials: S
authors.lastname: Zhong
authors.affiliation: Department of Chemistry, Gachon University, Seongnam-Si, Gyeonggi-Do 461-701, Korea. Electronic address: chjang4u@gachon.ac.kr.
authors.forename: Chang-Hyun
authors.initials: CH
authors.lastname: Jang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D001713:Biphenyl Compounds / Q000737:chemistry*; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D004867:Equipment Design; D005947:Glucose / Q000032:analysis* / Q000378:metabolism; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism; D006046:Gold / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D050866:Liquid Crystals / Q000737:chemistry* / Q000528:radiation effects; D009570:Nitriles / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D001713:Biphenyl Compounds; D004800:Enzymes, Immobilized; D009570:Nitriles; C433919:4-cyano-4'-pentylbiphenyl; D006046:Gold; D005949:Glucose Oxidase; D005947:Glucose
keywords: Biosensors; Glucose oxidase; Liquid crystals; Optical response; PH-driven phenomenon