Dapsone uptake and release from plasma polypyrrole for drug administration

A study on dapsone uptake and release model in plasma polypyrrole for drug administration in the central nervous system is presented in this work. The polymer was treated by lyophilization to induce pores on the surface that housed the drug. After that, the polymer was immersed in dapsone–ethanol solutions at different concentrations to introduce the drug into the pores, which once filled the pores, covered the polymer particles. The release of dapsone was tested in water and Krebs–Ringer solutions measured by UV–Vis spectroscopy considering surrounding static and dynamic fluids. The release in both models increased with the contact time in the fluids following linear tendencies. In all cases, the dissolution of the outer dapsone layer of the polymer particles occurred in the first 5 min, which was approximately 10 % of the total dapsone loaded. Dapsone was released at a higher rate in KR solutions than in water, which suggests that the ions of the KR salts help in this process. Morphology and chemical structures are studied before and after adding the drug to the polymer.