RESUMEN
Biomimetic nanoparticles are hybrid nanostructures in which the uppermost layer is similar to a cell membrane. In these nanoparticles, lipids and biopolymers can be organized to improve drug incorporation and delivery. This report provides instructions for the preparation and physical characterization of four different biomimetic nanoparticles: (1) polystyrene sulphate (PSS) nanoparticles covered with one cationic dioctadecyl dimethylammonium bromide bilayer (DODAB), which incorporates dimeric channels of the antimicrobial peptide Gramicidin D; (2) silica nanoparticles covered with one single bilayer of the antimicrobial cationic lipid DODAB; (3) hybrid lipid/polymer indomethacin (IND) nanoparticles from injection of IND/DODAB ethanolic solution in a water solution of carboxymethyl cellulose (CMC); (4) bactericidal and fungicidal nanoparticles from DODAB bilayer fragments (BF) covered consecutively by a CMC and a poly(diallyl dimethyl ammonium chloride) (PDDA) layer. These examples provide the basis for the preparation and characterization of novel biomimetic nanoparticles with lipids and/or biopolymers in their composition. The polymers and lipids in the hybrid nanoparticle composition may impart stability and/or bioactivity and/or provide adequate microenvironments for carrying bioactive drugs and biomolecules.
Asunto(s)
Antibacterianos/síntesis química , Lípidos/química , Polímeros/química , Adsorción , Antibacterianos/química , Mimetismo Biológico , Sistemas de Liberación de Medicamentos , Membrana Dobles de Lípidos/química , NanopartículasRESUMEN
Polymer microgels have received considerable attention due to their great potential in the biomedical field as drug delivery systems. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan composed of N-acetyl-d-glucosamine and d-glucuronic acid. This polymer is biodegradable, nontoxic, and can be chemically modified. In this work, a co-flow microfluidic strategy for the preparation of biodegradable HA microgels encapsulating hydrophobic drugs is presented. The approach relies on: (i) generation of a primary oil-in-water (O/W) nanoemulsion by the ultrasonication method, (ii) formation of a double oil-in-water-in-oil emulsion (O/W/O) using microfluidics, and (iii) cross-linking of microgels by photopolymerization of HA precursors modified with methacrylate groups (HA-MA) present in the aqueous phase of the droplets. The procedure is used for the encapsulation and controlled release of progesterone. Degradability and encapsulation/release studies in PBS buffer at 37°C in presence of different concentrations of hyaluronidase are performed. It is demonstrated that enzymatic degradation can be used to trigger the release of progesterone from microgels. This method provides precise control of the release system and can be applied for the encapsulation and controlled release of different types of hydrophobic drugs.