A liquid crystal-based biosensor for detection of insulin driven by conformational change of an aptamer at aqueous-liquid crystal interface

Jiamei Chen; Zhenping Liu; Ruizhi Yang; Mengjun Liu; Haoqiang Feng; Na Li; Mingliang Jin; Minmin Zhang; Lingling Shui

doi:10.1016/j.jcis.2022.07.051

A liquid crystal-based biosensor for detection of insulin driven by conformational change of an aptamer at aqueous-liquid crystal interface

J Colloid Interface Sci. 2022 Dec 15;628(Pt A):215-222. doi: 10.1016/j.jcis.2022.07.051. Epub 2022 Jul 19.

Authors

Jiamei Chen¹, Zhenping Liu¹, Ruizhi Yang¹, Mengjun Liu², Haoqiang Feng¹, Na Li³, Mingliang Jin⁴, Minmin Zhang⁵, Lingling Shui⁶

Affiliations

¹ Joint Laboratory of Optofluidic Technology and System, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics , School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China.
² Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China.
³ Joint Laboratory of Optofluidic Technology and System, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics , School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China.
⁴ Joint Laboratory of Optofluidic Technology and System, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics , School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China; International Academy of Optoelectronics at Zhaoqing, South China Normal University, Zhaoqing 526238, PR China.
⁵ Joint Laboratory of Optofluidic Technology and System, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics , School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China. Electronic address: zhangminmin@m.scnu.edu.cn.
⁶ Joint Laboratory of Optofluidic Technology and System, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics , School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, PR China. Electronic address: shuill@m.scnu.edu.cn.

PMID: 35930954
DOI: 10.1016/j.jcis.2022.07.051

Abstract

Insulin is a critical predictor for the function of pancreatic islet beta cells, which plays a crucial role in diagnosing diabetes and diabetes-related disorders. Herein, we propose and validate a label-free and cost-effective aptamer-based optical LC biosensor for detection of insulin based on the directional recognition of biomolecular binding events at a responsive aqueous-liquid crystal (LC) interface. The binding of insulin and aptamer adsorbed on CTAB triggers a conformational change of the aptamer from G-quadruplex to stretched structure, inducing homeotropic to planar alignment and correspondingly dark to bright optical image change of the LC films. The molecular dynamic (MD) simulation validates that the orientational transition is associated with the interaction energy changes at the interface, which is in coordination with the optical observation. This LC biosensor takes advantages of simple preparation, easy operation, rapid sensing, high specificity for insulin determination in the range of 0.1-1.0 nM within 5 min. This sensor is also applicable for insulin detection in diluted human urine and serum. Additionally, the optical cell arrays allow to detection multiple samples of the same/different biomarkers at the same time. Such a strategy offers a potential basis for monitoring other clinical biomarkers, and for point-of-care testing (POCT) as well.

Keywords: Conformational change; Insulin; Liquid crystal; Orientational transition; Responsive interface.

MeSH terms

Biosensing Techniques* / methods
Cetrimonium
Humans
Insulin
Liquid Crystals* / chemistry
Oligonucleotides
Water / chemistry

Substances

Insulin
Oligonucleotides
Water
Cetrimonium