Mathematical modelling of doxorubicin controlled release from smart biopolymer gel microspheres.

BOSIO VALERIA; M. V. SANTOS; N. ZARITZKY; CASTRO G.

Taipei

Congreso; The 5th International Conference on Industrial Bioprocesses.; 2012

National Taiwan University of Science and Technology

Doxorubicin (Dox) was encapsulated in 35.0 and 55.0% methoxylation degree (DE) Pectins (Pec) by ionotropic gelation with Ca+2 showing 88.0 and 66.0% loading capacity. Dox kinetic release from Pec 35.0 and 55.0% microspheres showed 90.0 and 33.0% free drug on PBS at pH 7.4, 37ºC for 120 min respectively. Meanwhile, only 17.0 and 11.0% free Dox from 35.0 and 55.0% Pec were released at pH 2.0, 37ºC for 120 min respectively. These results were compared with similar systems of release (pH/temperature) but using non-chelating organic buffer (HEPES). Matrix morphologies of the microparticles were compared during the controlled release processes with and without chelating agents. Additionally, Pec 55.0% microspheres has high stability decreasing the Dox release from 15 to 10% after one year storage at 4ºC. Mathematical and numerical modeling was applied in order to analyze drug release kinetics from matrices of spherical shape under the different studied conditions at 37ºC. The mathematical model representing the problem of diffusion-controlled drug release is established by second order partial differential equations in spatial coordinates of transient state. The numerical approach was implemented using the finite element method. The models were able to reproduce the drug release into a finite volume of well-stirred liquid.