title: Stereoselective histidine sensor based on molecularly imprinted sol-gel films.
abstract: A piezoelectric sensor coated with a thin molecularly imprinted sol-gel film has been developed for the determination of L-histidine in the liquid phase. Without preprotection, L-histidine was imprinted directly into silica sol-gel films that consisted of a hybrid mixture of functionalized organosilicon precursors (phenyltrimethoxysilane and methyltrimethoxysolane). The viscoelasticity of the film in the air and in buffer solution has been studied by the piezoelectric quartz crystal impedance technique. The binding of L-histidine to the imprinted film in the liquid phase was investigated by the piezoelectric microgravimetry and electrochemical impedance technique. Scatchard analysis showed that the maximum binding site (Qmax) of the L-histidine imprinted sol-gel film is about 23.7 micromol/g. A linear range from 5.0x10(-8) to 1.0x10(-4) M for a detection of L-histidine has been observed with a detection limit of 2.5x10(-8) M for S/N=3. The proposed imprinted sol-gel sensor exhibits good stability, high specificity, and excellent stereoselectivity.
authors.affiliation: State Key Laboratory of Chem/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Zhang
authors.forename: Haiping
authors.initials: H
authors.lastname: Liao
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Lihua
authors.initials: L
authors.lastname: Nie
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004548:Elasticity; D004563:Electrochemistry; D005782:Gels / Q000737:chemistry; D006639:Histidine / Q000032:analysis*; D012822:Silicon Dioxide
chemical_list: D005782:Gels; D006639:Histidine; D012822:Silicon Dioxide