[Preparation and in vitro characterization of apigemin-loaded nanostructured lipid carriers].

OBJECTIVE: To prepare Apigemin-loaded nanostructured lipid carriers (Api-NLCs) and evaluate their characteristics. METHODS: Api-NLCs were prepared by the method of emulsion evaporation-solidification at low temperature. The physicochemical properties such as morphology, size distribution, zeta potential, entrapment efficiency, drug loading and drug release in vitro were evaluated. RESULTS: The obtained nanoparticles were spherical under transmission electron microscope. The mean diameter was 212.1 nm, the zeta potential was - 14.65 mV, the mean entrapment efficiency was 82.4% and the mean drug loading was 0.97%. The total drug release was 30% in 2 hours followed by a slow and sustained release in vitro. CONCLUSION: The optimal Api-NLCs show stable characteristics and broad prospects for application.

[Preparation and characterization of curcumin polybutylcyanoacrylate nanoparticles].

OBJECTIVE: To prepare curcumin polybutylcyanoacrylate nanoparticles (Cur-PBCNs) and evaluate its characteristics. METHODS: Cur-PBCNs were prepared by emulsion polymerization, and the formulation was optimized by L16 (4(3)) orthogonal design test with entrapment efficiency and drug loading as indices. In addition, its characteristics were investigated. RESULTS: The nanoparticles were spherical in appearance under transmission electron microscope (TEM). The mean diameter of the nanoparticles was 93.8 nm, the mean entrapment efficiency was (50.4 +/- 2.2)%, the mean drug-loading was (33.5 +/- 0.9)% and the Zeta potential was -6.81 mV. The total drug release was 34.74% in 2 hours followed by a sustained release in vitro for Cur-PBCNs, and the in vitro release profile of the nanoparticles was fit for two phases kinetics equation: 100 - Q = 4.5235e(-0.1724t) + 4.1641e(-0.0114t). CONCLUSION: The optimal Cur-PBCNs show good characteristics and sustained release character in vitro.

Polymer-drug conjugates: present state of play and future perspectives.

Polymer conjugation is an efficient approach to improve therapeutic properties of drugs and biological agents. Since the first synthetic polymer-drug conjugate entered clinical trials in 1994, this technology has undergone notable development for the introduction and study of novel polymers and for the progress in the biological rationale for designing conjugates. Not surprisingly, new polymers, in addition to the best known polyethylene glycol, poly[N-(2-hydroxypropyl)methacrylamide], are continuously conjugated with drugs to achieve biodegradable, stimuli-sensitive and targeted systems in an attempt to prolong blood circulation times and enhance drug concentrations at the intended site of action. This overview focuses on bioconjugates of water-soluble polymers with low molecular weight drugs. Additionally, the most recent achievements in the polymer-drug conjugate field and several promising approaches for the future are discussed.