title: Measurement of enthalpy and volume changes in photoinitiated reactions on the ms timescale with a novel pressure cell.
abstract: Time-resolved photoacoustics is an excellent method with which to measure enthalpy and volume changes of photochemical and photobiological reactions. However, it fails at times longer than approximately 10 micros. The design principles of a pressure or volume cell covering the time range of 20 micros to several seconds is presented. The sensitivity of the cell has been verified and its application to the photocycle of bacteriorhodopsin is presented. Because of the similar cell structure and data analysis it is now possible to determine enthalpy and volume changes in photo-initiated reactions over the timescale of nanoseconds to seconds with the same solution.
authors.affiliation: The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. mauzera@mail.rockefeller.edu
authors.forename: David
authors.initials: D
authors.lastname: Mauzerall
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Edens
authors.forename: Joseph
authors.initials: J
authors.lastname: Grzymski
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D001436:Bacteriorhodopsins / Q000737:chemistry*; D004867:Equipment Design; D010777:Photochemistry; D013816:Thermodynamics; D013997:Time Factors
chemical_list: D001436:Bacteriorhodopsins