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PubMed · 4528511

Diffusion of polymer gel implants.

B K Davis
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Abstract

Crosslinked polyacrylamide and polyvinylpyrrolidone gels have been used to subcutaneously implant (125)I-labeled immunoglobulin, (125)I-labeled luteinizing hormone, (125)I-labeled bovine serum albumin, (125)I-labeled insulin, [(3)H]prostaglandin F(2alpha), and Na(125)I into hamsters. From the rates of absorption of the solutes, their diffusion coefficients were determined. The diffusion coefficients showed a logarithmic dependence on implant polymer concentration and solute molecular weight. Release of the solutes from gel preparations incubated 10 mM phosphate buffer (pH 7.2) at 37 degrees revealed a similar relationship between solute diffusion coefficient, molecular weight, and the concentration of polymer. A general equation was derived that gives the expected diffusion coefficient of a substance in a polymer gel from its molecular weight, diffusion coefficient in solvent, and polymer concentration of the gel.

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AcrylamidesAnimalsBiological AvailabilityCricetinaeDelayed-Action PreparationsDiffusionGelsHydrogen-Ion ConcentrationImmunoglobulinsInsulinIodine RadioisotopesLuteinizing HormoneMesocricetusPharmaceutic AidsPovidoneProstaglandinsSerum Albumin, BovineTemperatureTritiumJournal Article

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B K Davis. 1974. Diffusion of polymer gel implants.. https://doi.org/10.1073/pnas.71.8.3120

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