Novel Poly (glycerol-adipate) Polymers Used for Nanoparticle Making: A Study of Surface Free Energy

Nanoparticles made of biodegradable polymers has become the best approach for nanoparticle making due to their compatibility with the human body.

New glycerol adipate polymers with hydroxyl group substituted with different percent of acyl group, sited as figures within the abbreviated name in the text, and triptophan were synthesized and proposed to be used in the preparction of dexamethason phosphate loaded nanoparticles, using the evaporation-deposition technique. The particle forming ability, size and distribution of the nanoparticles might be related to more important physicochemical characteristics, such as the surface properties of the polymers.

In this study surface free energies of five derivatives (0%, 20%, 40%, 100% and triptophan 5%) were determined by means of contact angle measurement carried out on films formed on the glass slides KSC Cam 100 instrument. The results were then incorporated into the Fowkes equation, toobtion the surface energy of the polymers. Also, different concentrations of methanol were used to obtion contact angles, which in turn were used to give the critical surface tension (γ_c) of the polymers, using the Zizman’s method.

The results of surface characteristics indicated that the 40% C₈ polymer was probably the most consistent, compared to the others during the preparation stage, in order to form smaller sized particles with a narrower distribution, correlating with the other works carried out on the loaded particles.

In conclusion, it seems that this method could be used to predict characteristics of polymers used for the selection of the best polymer in this series and probably other polymers for nanoparticle making, particularly for the loading of ionized drugs.