title: Highly-sensitive liquid crystal biosensor based on DNA dendrimers-mediated optical reorientation.
abstract: A novel highly-sensitive liquid crystal (LC) biosensing approach based on target-triggering DNA dendrimers was developed for the detection of p53 mutation gene segment at the LC-aqueous interface. In this study, the mutant-type p53 gene segment was the target to trigger the formation of DNA dendrimers from hairpin DNA probes by hybridization chain reaction, and the latter as a 'signal enhancement element' further induced the LC reorientation from tilted to homeotropic alignment, resulting in a corresponding optical changes of LC biosensors from birefringent to honeycombed textures or dark framework. The distinct optical reorientational appearances can serve as a characteristic signal to distinguish target concentrations ranging from 0.08 nM to 8 nM. Moreover, these optical phenomena suggest that the LC reorientation is related to the electric-dipole coupling between the adsorbed DNA and LC molecules, the conformational constraints of DNA and the internal electric field induction upon hybridization. This label-free LC biosensing strategy can open up a new platform for the sensitive detection of specific DNA sequences and enrich the application scope of an LC biosensing technique.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Tan
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Xia
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Shuzhen
authors.initials: S
authors.lastname: Liao
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Ruqin
authors.initials: R
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China. Electronic address: zywu@hnu.edu.cn.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Wu
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis* / Q000235:genetics; D050091:Dendrimers / Q000737:chemistry*; D006801:Humans; D050866:Liquid Crystals / Q000737:chemistry*; D009154:Mutation; D009693:Nucleic Acid Hybridization; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: D050091:Dendrimers; D016159:Tumor Suppressor Protein p53; D004247:DNA
keywords: Biosensor; DNA dendrimer; Hybridization chain reaction; Liquid crystal; Optical reorientation