Development and characterization of lipopolymeric particles for the encapsulation of a synthetic hydrophilic nature peptide

Background: The development of micro- and nanoparticulate systems for the controlled delivery of synthetic peptides represents a significant advancement in creating new pharmaceutical products with diverse applications. Objectives: This study aimed to develop a lipopolymeric hybrid system (LPS) designed to encapsulate a hydrophilic synthetic peptide, using a traditional polymeric system (PS), a lipidic system (LS) as references. The systems were prepared using the double emulsion formation method (W1/O/W2), followed by the extraction and evaporation of the organic solvent. Results: All systems exhibited a spherical shape, a negative Z-potential, and encapsulation efficiencies ranging from 40.4% to 57.42%, with micrometric sizes for the polymeric (3,080-4,920 nm) and lipopolymeric systems (3,030-3,930 nm). The lipidic system showed nanometric sizes (136-163 nm). The encapsulated synthetic peptide was fully released in about 25 days in the LPS, compared to 45 days for the PS and 8 days in the LS. Although PS provides benefits in encapsulation efficiency and release time, incorporating a lipid component can significantly extend its residency time in the body. This is particularly crucial when utilizing a peptide for targeted therapies, as it helps the body avoid recognizing it as a foreign substance, leading to more effective treatment outcomes. Conclusion: this innovative experimental approach successfully establishes a highly effective hybrid lipopolymeric system for encapsulating an hydrophilic synthetic peptide, merging the beneficial features of both polymeric microparticles and solid lipid nanoparticles, and positioning itself as a leading option for their encapsulation and delivery in pharmaceutical applications.