ABSTRACT
Objective: To optimize the preparation method of triptolide-nano-liposomes (TP-NLS). Methods High pressure homogeneous method was used to prepare TP-SLN. According to even design U7(73), the preparation method of TP-SLN was optimized with the factors including weight ratio of phosphorlipid and cholesterol (A), quantity of Poloxamer 188 (B), and homogeneous pressure (C), using the encapsulation efficiency (EE), particle size, and Zeta potential of NLS as indexes. Results: The optimum prescription of TP-NLS was A1B5C7, i.g. lipid matrix a : b was 6 : 1, the dosage of Poloxamer 188 was 1.3 g, and the homogeneous pressure was 70 MPa, high pressure homogeneous method for 15 min. The TP-NLS prepared with the optimal method had good appearance. The EE was 83.52%, the average particle size was 117 nm, and the Zeta potential was 31.7 mV. TP-NLS solution was kept in avoiding light environment at 4℃ for 30 d, and the preservation stability was good. Conclusion: The formula is reasonable and the preparation method of TP-NLS is feasible, which is valuable to further study.
ABSTRACT
Objective To prepare drug carrier non-PEG blank liposomes, and study its properties.Methods High purity of egg yolk lecithin and cholesterol were used as film forming material.The high pressure homogeneous method-extrusion method and high pressure homogeneous method-ultrasonic method were used to prepare non-PEG blank liposomes.After that how the method of high pressure homogeneous, extrusion and ultrasonic influence the particle size of blank liposomes were studied, and the physical stability of blank liposomes were investigated.ResuIts The particle size of blank liposomes prepared by high pressure homogeneous method-extrusion method was about 86 nm, and its polydispersity index was 0.170.While the particle size of the blank liposomes prepared by high pressure homogeneous method-ultrasonic method was about 91 nm, and its polydispersity index was 0.362.ConcIusion Compared with high pressure homogeneous method-ultrasonic method, the blank liposomes prepared by high pressure homogeneous method-extrusion method had some advantanges, such as smaller particle size, narrow particle size distribution and high stability.
ABSTRACT
BACKGROUND: National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) is the guideline for detection evaluation, and treatment of high blood cholesterol in adults. The risk of coronary heart disease (CHD) is assessed by the presence of CHD risk equivalents and the number of risk factors. LDL-cholesterol is the goal of treatment for hyperlipidemia. Contents: The most common approach for determining LDL-cholesterol level in clinical laboratory is to calculate it based on Friedewald formula. For accurate risk assessment by the calculated LDL-cholesterol, good analytical performances of total cholesterol, HDL-cholesterol and triglyceride are prerequisite. Even if the analytical performance of these three analytes are within the acceptable criteria, pooled imprecision and bias of the calculated LDL-cholesterol could not meet the criteria for LDL-cholesterol. Even under conditions satisfying the requirements of Friedewald formula, the calculated LDL-cholesterol level was lower than the directly measured level and the difference was dependent on the level of triglyceride, LDL-cholesterol and total cholesterol. When evaluatingpatients with hyperlipidemia, Friedewald calculation may underestimate the risk for coronary heart disease which may lead to inappropriate treatment option. CONCLUSIONS: When evaluating patients with hyperlipidemia, direct measurement of LDL-cholesterol appears to be better than Friedewald calculation.