title: A Q-switched Ho:YAG laser assisted nanosecond time-resolved T-jump transient mid-IR absorbance spectroscopy with high sensitivity.
abstract: Knowledge of dynamical structure of protein is an important clue to understand its biological function in vivo. Temperature-jump (T-jump) time-resolved transient mid-IR absorbance spectroscopy is a powerful tool in elucidating the protein dynamical structures and the folding/unfolding kinetics of proteins in solution. A home-built setup of T-jump time-resolved transient mid-IR absorbance spectroscopy with high sensitivity is developed, which is composed of a Q-switched Cr, Tm, Ho:YAG laser with an output wavelength at 2.09 μm as the T-jump heating source, and a continuous working CO laser tunable from 1580 to 1980 cm(-1) as the IR probe. The results demonstrate that this system has a sensitivity of 1 × 10(-4) ΔOD for a single wavelength detection, and 2 × 10(-4) ΔOD for spectral detection in amide I' region, as well as a temporal resolution of 20 ns. Moreover, the data quality coming from the CO laser is comparable to the one using the commercial quantum cascade laser.
authors.affiliation: Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Deyong
authors.initials: D
authors.lastname: Li
authors.affiliation: Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Yunliang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China.
authors.forename: Xianyou
authors.initials: X
authors.lastname: Wu
authors.affiliation: School of Physics and Optoelectronic Technology, Dalian University of Technology, No. 2, Linggong Road, Dalian 116023, China.
authors.forename: Qingxu
authors.initials: Q
authors.lastname: Yu
authors.affiliation: Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Yuxiang
authors.initials: Y
authors.lastname: Weng
mesh_terms: D000818:Animals; D045304:Cytochromes c / Q000737:chemistry; D004867:Equipment Design; D006321:Heart; D006736:Horses; D007700:Kinetics; D053844:Lasers, Solid-State; D011189:Potassium Chloride / Q000737:chemistry; D013055:Spectrophotometry, Infrared / Q000295:instrumentation* / Q000379:methods*; D013997:Time Factors
chemical_list: D011189:Potassium Chloride; D045304:Cytochromes c