RESUMEN
Polymer self-healing is mainly based on the molecular structure and interaction of polymers, and some need external stimulation, such as light, heat, pH, etc. In recent years, many studies have found that the self-healing properties of polymers can prolong the life of materials, while maintaining the mechanical properties of polymers after healing. According to the different action modes of polymer materials, it can be divided into autonomous self-healing and non-autonomous self-healing. Among them, autonomous self-healing mainly works through reversible covalent bonds (Schiff base bond, Diels-Alder reaction, hydrazide bond), reversible non-covalent bonds (hydrogen bond, metal-ligand coordination bond, electrostatic interaction, π-π stacking interaction, hydrophobic interaction) and a combination of the two interactions. Drug carriers with unique self-healing properties play an important role in the encapsulation and stable release of biomacromolecules. In this review, the self-healing mechanism of polymers and their applications in the field of biomedicine were briefly summarized and discussed.
RESUMEN
Objective To prepare water-in-oil gardenoside emulsion, optimize its formulation process, and evaluate the quality. Methods The formulation was optimized based on emulsification time, oil floating time and phase separation time, and investigated the optimal gardenoside emulsion by the single factor investigation and mixture design. The properties, stability, content, and in vitro release of the emulsion were also studied. Results The mean particle size of gardenoside emulsion was (5.48 ± 0.02) μm and the value of PDI was 0.125 ± 0.096; Centrifugation accelerated test was performed at 4 000 r/min for 15 min without delamination; The average mass fraction of gardenoside emulsion was 92.14% and RSD was 1.86% (n = 3); The in vitro release of gardenoside emulsions at pH 4.5, 6.8, and 7.4 was up to 105.32%, 98.41%, and 98.70%, respectively, while the in vitro release at pH 1.2 was up to 63.45%; Finally, the law of drug release was explained by fitting equation. Conclusion The high speed shear mechanical method can be used to prepare gardenoside emulsion, and the quality evaluation of the optimized prescription meets the requirements.