title: Aggregation kinetics of colloidal particles destabilized by enzymes.
abstract: Dynamic light scattering was used to measure enzymatic activity by monitoring the rate of destabilization of colloidal particles coated with proteins or carbohydrates. The photon autocorrelation spectrum was analyzed using a cumulant expansion or direct inversion. In all cases, the measured average diffusion coefficient and the standard deviation of the diffusion coefficient decreased with time. A kinetic model with a bimodal particle distribution function was used to represent the time dependence of the cumulants. The cumulants are very sensitive to the details of the particle distribution.
authors.affiliation: Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.
authors.forename: A K
authors.initials: AK
authors.lastname: Gaigalas
authors.forename: H H
authors.initials: HH
authors.lastname: Weetall
mesh_terms: D000681:Amylases / Q000737:chemistry*; D002627:Chemistry, Physical / Q000379:methods; D003102:Colloids / Q000737:chemistry*; D004355:Drug Stability; D010450:Endopeptidases / Q000737:chemistry*; D007700:Kinetics; D008027:Light; D010316:Particle Size; D011506:Proteins / Q000737:chemistry; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013213:Starch / Q000737:chemistry; D014357:Trypsin / Q000737:chemistry
chemical_list: D003102:Colloids; D011506:Proteins; D012710:Serum Albumin, Bovine; D013213:Starch; D000681:Amylases; D010450:Endopeptidases; D014357:Trypsin