title: The Effect of Swelling Ratio on the Coulter Underestimation of Hydrogel Microsphere Diameters.
abstract: It has been demonstrated that the diameters of porous particles are underestimated by Coulter measurements. This phenomenon has also been observed in hydrogel particles, but not characterized. Since the Coulter principle uses the displacement of electrolyte to determine particle size, electrolyte contained within the swelled hydrogel microparticles results in an underestimate of actual particle diameters. The increased use of hydrogel microspheres in biomedical applications has led to the increased application of the Coulter principle to evaluate the size distribution of microparticles. A relationship between the swelling ratio of the particles and their reported Coulter diameters will permit calculation of the actual diameters of these particles. Using polyethylene glycol diacrylate hydrogel microspheres, we determined a correction factor that relates the polymer swelling ratio and the reported Coulter diameters to their actual size.
authors.affiliation: Department of Biomedical Engineering, Rutgers University , Piscataway, New Jersey.
authors.forename: Michael
authors.initials: M
authors.lastname: Pellegrini
authors.affiliation: Department of Biomedical Engineering, Rutgers University , Piscataway, New Jersey.
authors.forename: Abhimanyu
authors.initials: A
authors.lastname: Cherukupalli
authors.affiliation: Department of Biomedical Engineering, Rutgers University , Piscataway, New Jersey.
authors.forename: Michael
authors.initials: M
authors.lastname: Medini
authors.affiliation: Department of Biomedical Engineering, Rutgers University , Piscataway, New Jersey.
authors.forename: Ron
authors.initials: R
authors.lastname: Falkowski
authors.affiliation: Department of Biomedical Engineering, Rutgers University , Piscataway, New Jersey.
authors.forename: Ronke
authors.initials: R
authors.lastname: Olabisi
mesh_terms: D020100:Hydrogels / Q000737:chemistry*; D008863:Microspheres; D010316:Particle Size
chemical_list: D020100:Hydrogels