[Study on quality standard for qiangnaosu capsule].

OBJECTIVE: To establish the quality standard for Qiangnaosu capsule. METHODS: TLC was used for the qualitative identification of Saposhnikoviae Radix, Chuanxiong Rhizoma, Chrysanthemum Flos, Fructus Viticis. HPLC was used to determine the content of ferulic acid. RESULTS: TLC spots were clear, well-separated and specific. The linear range of ferulic acid was 2.93 - 20.50 microg/mL (r = 0.9996). The average recovery was 98.1% and RSD was 1.42%. CONCLUSION: The method is reliable and specific. It can be used for the quality control of Qiangnaosu capsule.

The pharmacokinetics of recombinant human interferon-alpha-2b poly(lactic-co-glycolic acid) microspheres in rats.

Interferon-alpha2b (IFN α-2b) microspheres were prepared at various concentrations (5%, 10%, 15%, 20% and 25%) and viscosities (0.39, 0.6, 0.89 and 1.13 dL/g) of poly(lactic-co-glycolic acid) (PLGA) using double emulsion solvent evaporation. The optimal formulation of IFN α-2b microspheres was determined to be 0.89 dL/g PLGA, as assessed by the in vitro release test. The pharmacokinetics of IFN α-2b microspheres was investigated. Nine groups of rats were injected intramuscularly with three doses (0.5, 1 and 2 MIU) of commercial lyophilized IFNα-2b injection or IFN α-2b microspheres. At a dose of 0.5 MIU, the IFN α-2b microsphere released significantly longer than that of the IFN α-2b injection. At a dose of 2 MIU, each pharmacokinetics parameter of microspheres prepared with the IFNa-2b stock solution was manifestly greater than those of the injection. Our study indicated that the IFN α-2b microspheres prepared in 15% of 0.89 dL/g PLGA provided a sustained drug effect for up to 21 days in rats.

Preparation and characteristics of interferon-alpha poly(lactic-co-glycolic acid) microspheres.

By a double emulsion solvent evaporation method, interferon-alpha (IFN-alpha) microspheres were prepared with poly(lactide-co-glycolide) (PLGA) and their characteristics, such as morphology, drug loading, encapsulation efficiency, in vitro release and degradation were evaluated. The IFN-alpha microspheres were prepared by different viscosities from 0.17-1.13 dL g(-1) and concentrations between 5-25% of PLGA, which not only affected the drug loading and encapsulation efficiency of IFN-alpha microspheres, but also strongly influenced the in vitro release. With smooth and porous surface, the drug loading and encapsulation efficiency of the microspheres prepared by 15% 0.89 dL g(-1) PLGA were 7.736% and 77.38%, respectively. The DSC curve of microspheres indicated IFN-alpha was loaded inside the microspheres. The degradation of microspheres was homogeneous and the mass loss was over 80% in 6 weeks. The release profile of microspheres showed a sustained fashion and the IFN-alpha released from microspheres maintained its bioactivity for 7 days.

Recombinant interferon-alpha2b poly(lactic-co-glycolic acid) microspheres: pharmacokinetics-pharmacodynamics study in rhesus monkeys following intramuscular administration.

AIM: Investigation into pharmacokinetic-pharmacodynamic properties of interferon- alpha (IFN-alpha)2b-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres (MS) in rhesus monkey primates. METHOD: IFN-alpha2b was loaded with biodegradable PLGA with 3 inherent viscosities using a double emulsion and solvent evaporation method. The particle size, surface morphology, and in vitro release profiles were investigated. Two groups of rhesus monkeys (n=3) were injected intramuscularly with either 3 MIU/kg commercial IFN-alpha2b lyophilized powder or IFN-alpha2b-loaded PLGA microspheres (inherent viscosity of 0.89 dL/g). In vitro release was determined by Lowry protein assay. The serum IFN and neopterin levels were determined by the enzyme-linked immunosorbent assay (ELISA) method to evaluate biological activity of the microspheres in rhesus monkeys. RESULTS: The IFN-alpha2b microspheres with 3 inherent viscosities (0.39, 0.89, and 1.13 dL/g) were entirely spherical and had a smooth surface. The average diameter of each type was 45.55, 81.23, and 110.25 microm, respectively. The in vitro release was 30 d. The pharmacokinetic-pharmacodynamic properties between the IFN-alpha2b microspheres and IFN-alpha2b lyophilized powder were significantly different (P<0.05). CONCLUSION: The drug residence time for the IFN-alpha2b of the PLGA microsphere with an inherent viscosity of 0.89 dL/g in plasma significantly increased and had a longer time of biological effects in rhesus monkeys following intramuscular administration.