Aggregation studies of humic acid using multiangle laser light scattering

An aqueous phase study of the naturally occurring dissolved organic carbon humic acid (HA) is performed using multiangle laser light scattering (MALLS) to measure its RMS radius and average molecular weight. A Zimm plot using Berry Formulism and a second-order fit gave an average molar mass of 1.164 x 10(8) g/mol and an average RMS radius (R-z) of 436.0 +/- 36 nm at 25 degrees C. (C) 2000 Elsevier Science B.V. All rights reserved.