Submicrosecond real-time fluorescence sampling: application to protein folding

Time-resolved fluorescence detection has become a central tool in the study of protein folding. This article briefly reviews modem fluorescence techni ques and then focuses on recent improvements made possible by array photomu ltipliers, computer-controlled data gating, and long-memory multi-channel d igitizers. It is now possible to detect fluorescence wavelength profiles an d/or fluorescence decay transients very cost effectively with sub-microseco nd kinetic time resolution out to long times. Folding kinetics can be analy zed by singular value decomposition (SVD) or chi-analysis. The latter provi des an objective method for detecting nonexponential kinetics in two-state systems. (C)2000 Elsevier Science S.A. All rights reserved.