title: Temperature-jump apparatus with Raman detection based on a solid-state tunable (1.80-2.05 microm) kHz optical parametric oscillator laser.
abstract: The operating characteristics of a pulsed (10 ns) tunable near-infrared (NIR) laser source are described for temperature-jump (T-jump) applications. A Q-switched Nd:YLF laser (approximately 10 ns pulses) with a 1 kHz repetition rate is used to pump a potassium titanyl arsenate (KTA) crystal-based optical parametric oscillator (OPO), producing approximately 1 mJ NIR pulses that are tunable (1.80-2.05 microm) across the 1.9 microm vibrational overtone band of water. This T-jump source has been coupled to a deep ultraviolet (UV) probe laser for Raman studies of protein dynamics. T-jumps of up to 30 degrees C, as measured via the O-H stretching Raman band of water, are readily achieved. Application to cytochrome c unfolding is demonstrated.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Gurusamy
authors.initials: G
authors.lastname: Balakrishnan
authors.forename: Ying
authors.initials: Y
authors.lastname: Hu
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Spiro
mesh_terms: D000818:Animals; D045304:Cytochromes c / Q000032:analysis; D006736:Horses; D007834:Lasers; D009211:Myoglobin / Q000378:metabolism; D013059:Spectrum Analysis, Raman / Q000295:instrumentation* / Q000379:methods*; D013696:Temperature
chemical_list: D009211:Myoglobin; D045304:Cytochromes c