ABSTRACT
OBJECTIVE： To prepare Paclitaxel（PTX）nanostructured lipid carriers （NLC） modified by small peptide alanine-glutamic acid-tyrosine-leucine-arginine （AEYLR）， and to evaluate its anti-tumor effect in vitro and in vivo. METHODS： NLC， PTX-NLC （P-NLC） and AEYLR modified P-NLC （A-P-NLC） were prepared by emulsion evaporation-low temperature solidification curing method. Its appearance， particle size， multi-dispersion index（PDI） and Zeta potential were characterized，encapsulation rate，drug loading and in vitro drug release were detected respectively. Using NCI-H1299 and S180 cells as objects， CCK-8 method was adopted to investigate inhibitory effects of free PTX， P-NLC and A-P-NLC （0.44-44.00 μg/mL， by PTX） to those cells. The half inhibition concentration （IC50） was calculated. Using S180 tumor-bearing mice as model animal， anti-tumor effects of free PTX， P-NLC and A-P-NLC （5 mg/kg， by PTX） were evaluated. RESULTS： P-NLC and A-P-NLC were round-like and dispersed evenly. The particle size， PDI and Zeta potential of A-P-NLC were （43.92±0.76） nm， 0.203±0.034 and （－19.77±1.16） mV， which were all increased to certain extent， compared with P-NLC. The encapsulation efficiency and drug loading of A-P-NLC were （95.71±0.68）％ and（1.97±0.25）％， which were both decreased to certain extent， compared with P-NLC. The cumulative release rate of A-P-NLC was（35.17±2.08）％ within 48 h， showing significant sustained-release effect compared with free PTX； the release of A-P-NLC was slower than P-NLC. Compared with free PTX and P-NLC， inhibitory rates of same concentration of A-P-NLC to NCI-H1299 cells and S180 cells were almost increased significantly， while IC50 values were all decreased significantly. There was no death in S180 tumor-bearing mice treated with A-P-NLC and the general condition was good； the volume of tumors was significantly reduced， the mass of tumors was significantly reduced， and the inhibition rate of tumors was significantly increased （P＜0.05 or P＜0.01）. CONCLUSIONS： A-P-NLC has significantly sustained-release effects； its inhibitory rate to NCI-H1299 cells and S180 cells in vitro， and its inhibitory effects on S180 solid tumor in mice are all better than free PTX and P-NLC， while the toxicity is decreased to certain extent.
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OBJECTIVE:To prepare rifampicin(RFP)nano-structured lipid carriers(RFP-NLCs)to improve its water-solubili-ty,and evaluate its quality. METHODS:Using liquid-solid lipid materials oleate and glyceryl monostearate as lipid materials,soy lecithin as emulsifier,poloxamer 188 as nonionic surfactant,melting-ultrasonic emulsification was used to prepare RFP-NLCs. Us-ing the comprehensive scores of particle size and encapsulation efficiency as indexes,the amount of lipid materials,proportion of liquid lipid materials,dosage,and mass ratio of soy lecithin-poloxamer 188 as factors,orthogonal test was adopted to optimize the formulation. The morphology,particle size,polydispersity index(PDI),Zeta potential,encapsulation efficiency,drug loading and in vitro release degree of prepared lipid carriers with optimal formulation were evaluated. RESULTS:In the optimal formulation, the amount of lipid materials was 150 mg,proportion of liquid lipid materials was 30%,amount of RFP was 10 mg,and mass ra-tio of soy lecithin-poloxamer 188 was 1:3. Prepared RFP-NLCs had rounded appearance,particle size was (124.07 ± 3.25) nm, PDI was 0.104±0.010,Zeta potential was(-31.07±2.94)mV,encapsulation efficiency was(80.90±2.59)%,and drug loading was(4.81±0.68)%(n=3). Compared with RFP raw materials,in vitro release degree of RFP-NLCs significantly slowed down, and the cumulative release degree within 12 h was 63.2%,which was in line with Weibull equation. CONCLUSIONS:Screened formulation can successfully prepare RFP-NLCs;the prepared RFP-NLCs have small particle size and high encapsulation efficien-cy,and the in vitro drug release shows certain sustained-release characteristics.
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Objective:To screen the optimal formula and technology of demethoxycurcumin nano-structured lipid carriers. Meth-ods:The encapsulation efficiency as the main investigation index, the single factor exploration and orthogonal design were used to study the main factors affecting the quality of the nanoparticles. The optimal formula and technology were obtained. Results:The optimized parameters were as follows:the ratio of drug to lipid materials was 1 ∶40, the ratio of liquid lipid to total lipid materials was 10%, the amount of surfactants was 4% and the amount of lecithin was 2%. The prepared nanoparticles were spheric and regular. The size dis-tribution of the nanoparticles was narrow with the average particle size of 110nm and PDI of 0. 199. Conclusion:The optimized formula and technology of demethoxycurcumin nano-structured lipid carriers are stable and practicable,which provide reference for the further research of demethoxycurcumin.
ABSTRACT
Objective Nano-structured lipid carriers ( NLC) is a concerned research area in pharmaceutics , which as a novel drug delivery system to promote oral absorption of poorly soluble drugs .The literatures were reviewed to explore and summarize the mechanism that nano-structured lipid carriers in promotion of the absorption of poorly soluble drugs .