End‐Chain Radiolabeling and in Vitro Stability Studies of Radiolabeled Poly(hydroxy acid) Nanoparticles
| Autor: | Michel Vert, J.P. Benoǐt, A.M. Le Ray, J.C. Gautier |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
chemistry.chemical_classification
Drug Carriers Polyesters Dispersity Pharmaceutical Science Nanoparticle Polymer Chloride Molecular Weight Acetic anhydride chemistry.chemical_compound Drug Stability chemistry Dynamic light scattering medicine Acetone Organic chemistry Carbon Radioisotopes Methylene medicine.drug Nuclear chemistry |
| Zdroj: | Journal of Pharmaceutical Sciences. 83:845-851 |
| ISSN: | 0022-3549 |
| DOI: | 10.1002/jps.2600830618 |
| Popis: | In order to study the tissue distribution of biodegradable nanoparticles after oral administration in animals, end-chain-radiolabeled poly(D,L-lactides) were prepared. Two groups of polymers (Mn = 7500, I = 2.4 and Mn = 28000, I = 1.4 as determined by organic size-exclusion chromatography) were chemically modified by reaction of [14C]acetic anhydride with hydroxyl end-chain groups. The activities of both resulting radioactive poly(D,L-lactides) varied from 57 to 1140 microCi/g. Poly(D,L-lactide) or poly(D,L-lactide-co-glycolide) nanoparticles containing various amounts of radioactive polymer were prepared according to the solvent evaporation process with acetone as cosolvent with methylene chloride in the organic phase. Their mean diameter was 133 +/- 25 nm, measured by photon correlation spectroscopy. The radiolabeled-end-group stability of these particles in buffer solutions was found to be greater when the matrix was made from the radiolabeled poly(D,L-lactide) having the highest molecular weight and the lowest polydispersity index. The polymer-chain stability was totally retained for at least 1 week in a phosphate buffer, pH 7.4, i.e. for the selected experiment time. |
| Databáze: | OpenAIRE |
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