Time-resolved Raman spectroscopy with a tunable ultraviolet kilohertz nanosecond laser
Time-resolved Raman spectroscopy with a tunable ultraviolet kilohertz nanosecond laser
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DOI：
10.1002/(sici)1097-4555(199909)30:9
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发表时间：
1999-09-01
影响因子：
2.5
通讯作者：
Spiro, TG
中科院分区：
文献类型：
--
作者：
Zhao, XJ;Tengroth, C;Spiro, TG
时间分辨共振拉曼（TR 3）光谱获得了一对Q开关的Nd：YLF泵浦的a：蓝宝石激光器，产生可调谐（810-920 nm）类似于20 ns的脉冲在1 kHz的重复率。在锂硼酸盐（LBO）中的倍频提供蓝色（405-460 nm）泵浦和探测脉冲，而UV探测脉冲可以通过在β-钡硼酸盐（BBO）中的二次谐波的倍频产生，从205到230 mm可调谐。实施定时序列，其中多通道检测器的曝光在泵浦脉冲与探测脉冲之间的正时间延迟与负时间延迟之间交替，使得累积的差谱没有来自摄谱仪漂移或样品的逐渐分解的伪影。该系统进行了测试的碳一氧血红蛋白（HbCO）的光循环，其中UV TR 3光谱先前已报道。在419 nm处，在强Soret吸收带的最大值处泵浦HbCO，并且通过测量用425 nm探测脉冲产生的HbCO和脱氧Hb nu（4）卟啉RR带的强度比来建立光响应的饱和（最大脱配）。UV TR 3差光谱，获得在0.06至20 μ s的时间间隔，使用229 nm的探针脉冲。它们与先前用一对300 Hz准分子-染料激光器记录的那些很好地一致，用1 kHz Nd：YLF-Ti：S激光器实现可比信噪比所需的时间短八倍，版权所有（C）1999 John Wiley & Sons，Ltd.
Time-resolved resonance Raman (TR3) spectra are obtained with a pair of Q-switched Nd:YLF-pumped a:sapphire lasers, generating tunable (810-920 nm) similar to 20 ns pulses at a 1 kHz repetition rate. Frequency doubling in lithium berate (LBO) provides blue (405-460 nm) pump and probe pulses, while UV probe pulses, tunable from 205 to 230 mm, can be generated by doubling the second harmonic in beta-barium berate (BBO), Pump and probe pulse timing are controlled electronically. A timing sequence is implemented in which exposure of the multichannel detector alternates between positive and negative time delays between pump and probe pulses, so that accumulated difference spectra are free of artifacts from spectrograph drift or gradual decomposition of the sample. The system was tested on the carbonmonoxy hemoglobin (HbCO) photocycle, for which UV TR3 spectra have previously been reported. HbCO was pumped at 419 nm, at the maxima of the strong Soret absorption band, and saturation of the photoresponse (maximum deligation) was established by measuring the intensity ratio of the HbCO and deoxyHb nu(4) porphyrin RR bands, generated with 425 nm probe pulses. UV TR3 difference spectra were obtained at time intervals from 0.06 to 20 mu s using 229 nm probe pulses. They are in good agreement with those recorded previously with a pair of 300 Hz excimer-dye lasers, The time required to achieve a comparable signal-to-noise ratio was eight times shorter with the 1 kHz Nd:YLF-Ti:S lasers, Copyright (C) 1999 John Wiley & Sons, Ltd.