Meas Sci Technol. 2023 Mar;34(3):035301. doi: 10.1088/1361-6501/aca993. Epub 2022 Dec 21.
ABSTRACT
Real-time viscosity measurement techniques have been used to analyze the transition of hydrogels from a liquid state to a gel state. Measuring real-time changes in viscosity can be done through passive rheometry with the addition of tracer particles. Particle Diffusometry quantifies Brownian motion of sub-micron sized fluorescent particles by computing diffusion coefficients via statistical averaging. Herein, we demonstrate a method to study viscosity changes as a function of time using Particle Diffusometry for a temporally and spatially resolved rheometry measurement technique. We refined the PD algorithm using synthetic images of particles suspended in a liquid undergoing a sigmoidally decreasing viscosity trend to simulate the viscosity change of the solution during gelation. Then, the technique is applied to visualize the temporal and spatial gradients of diffusion coefficient during polyacrylamide hydrogel formation experiments. This work establishes the groundwork for quantifying over time changes in Brownian motion.
PMID:40207254 | PMC:PMC11981600 | DOI:10.1088/1361-6501/aca993
