title: A nonionic surfactant-decorated liquid crystal sensor for sensitive and selective detection of proteins.
abstract: Proteins are responsible for most biochemical events in human body. It is essential to develop sensitive and selective methods for the detection of proteins. In this study, liquid crystal (LC)-based sensor for highly selective and sensitive detection of lysozyme, concanavalin A (Con A), and bovine serum albumin (BSA) was constructed by utilizing the LC interface decorated with a nonionic surfactant, dodecyl β-d-glucopyranoside. A change of the LC optical images from bright to dark appearance was observed after transferring dodecyl β-d-glucopyranoside onto the aqueous/LC interface due to the formation of stable self-assembled surfactant monolayer, regardless of pH and ion concentrations studied in a wide range. The optical images turned back from dark to bright appearance after addition of lysozyme, Con A and BSA, respectively. Noteworthy is that these proteins can be further distinguished by adding enzyme inhibitors and controlling incubation temperature of the protein solutions based on three different interaction mechanisms between proteins and dodecyl β-d-glucopyranoside, viz. enzymatic hydrolysis, specific saccharide binding, and physical absorption. The LC-based sensor decorated with dodecyl β-d-glucopyranoside shows high sensitivity for protein detection. The limit of detection (LOD) for lysozyme, Con A and BSA reaches around 0.1 μg/mL, 0.01 μg/mL and 0.001 μg/mL, respectively. These results might provide new insights into increasing selectivity and sensitivity of LC-based sensors for the detection of proteins.
authors: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education, Jinan, 250100, PR China.
authors: Yi
authors: Y
authors: Wang
authors: Department of Chemistry, University of Houston, Houston, TX 77204, USA.
authors: Qiongzheng
authors: Q
authors: Hu
authors: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education, Jinan, 250100, PR China; School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, PR China.
authors: Tongtong
authors: T
authors: Tian
authors: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, PR China.
authors: Yan'an
authors: Y
authors: Gao
authors: Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education, Jinan, 250100, PR China. Electronic address: ylmlt@sdu.edu.cn.
authors: Li
authors: L
authors: Yu
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002417:Cattle; D003208:Concanavalin A / Q000032:analysis*; D005960:Glucosides / Q000032:analysis; D006046:Gold / Q000737:chemistry; D050866:Liquid Crystals / Q000737:chemistry*; D009113:Muramidase / Q000032:analysis*; D012710:Serum Albumin, Bovine / Q000032:analysis*; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D005960:Glucosides; D013501:Surface-Active Agents; D003208:Concanavalin A; D012710:Serum Albumin, Bovine; C038732:dodecyl glucoside; D006046:Gold; D009113:Muramidase
keywords: Bovine serum albumin; Concanavalin A; Liquid crystals; Lysozyme; Nonionic surfactant; Sensor