A new method for measuring fast aggregation rate based on the growth of the colloidal aggregate size

We propose a novel technique to determine the absolute fast aggregation rate directly from the growth curve of the aggregate size. Our approach is convenient and effective as it eliminates the need for calculations of optical properties and does not require a precise zero point of aggregation time, which are both essential in traditional light-scattering methods. Through comparisons with conventional turbidity measurements, the reliability and precision of this new approach are verified for both homogeneous and heterogeneous aggregation.