Screening of Electrolyte Complexes Formed Between Dextran Sulfate and Amine Structures of Small-Molecule Drugs

Formation of an electrolyte complex using the electrostatic interactions between a polyanionic polymer and a cationic drug is a simple and efficient method of preparing a colloidal drug carrier system. Dextran sulfate, with a negatively charged sulfate group, was reacted in an acetate buffer solution of pH 3 with positively charged 1° amine, 2° amine, 3° amine, piperazine, and piperidine structures from 24 small-molecule drugs. The electrolyte complex was formed from 15 drugs, 63% of those tested. The tendency to form the electrolyte complex was in the order of piperazine and piperidine >3° amine >>2° amine. The drugs with the 1° amine structure failed to form an electrolyte complex. The mean particle sizes were in the range of 50-740 nm, and most of them showed a submicron colloidal dispersion of <400 nm. Regarding drug encapsulation efficiency (%), 11 drugs with piperazine, piperidine, and 3° amine structures showed 60–98% efficiency, which was fairly high. The results suggest that directly forming the electrolyte complex with dextran sulfate yields promising structural attributes as a submicron colloidal drug carrier system.

Recent Advances in Nanocapsule: Types, Preparation Methods and Characterizatio

Nanocapsules are submicroscopic colloidal drug carrier systems consist of a liquid/solid core in which the drug, gene, protein, and other substances are incorporated into the interior cavity that is surrounded by a distinctive polymeric membrane. Polymers like collagen, albumin, and gelatin are mainly using polymers in nanocapsule formulations. Nanocapsules can serve as nano-sized drug carriers to achieve controlled release as well as efficient drug targeting. The process is used to improve the poor aqueous drug solubility, taste, stabilizing drugs by protecting the molecule from the environment, providing the desired pharmacokinetic profile, allowing controlled release, as well as facilitating oral administration. Capsules are generally prepared between the range of 100 and 1000 nm. Their release and degradation properties largely depend on the composition and the structure of the capsule walls. The dispersion stability of nanocapsules determined by the surfactant, nature of the outer coating. This review describes various facts of nanocapsule drug delivery systems in relation to the method of formulation, characterization, potential benefits and risks, and pharmaceutical applications in drug delivery.