[Research & development and evaluation of oral films].

Oral film is a new type of oral preparation. Due to portability, simple preparation process and good clinical compliance, oral films have become the focus of novel drug delivery system in recent years. Meanwhile, oral films have been gradually used in the development of Chinese medicine preparations. According to the application and approval situation of different types of oral films both at home and abroad in recent years, their research and development status was analyzed, including the basic concept, formulation, manufacturing process and quality control, as well as related progress and development prospects of oral films applied in traditional Chinese medicine. Some suggestions on the technical evaluation of oral films were put forward by considering specific requirements from regulatory agencies. This paper could provide some references for the development and evaluation of oral films. Due to the complexity of the drug substances and the particularity of the drug product, the development and application of oral films in traditional Chinese medicine are still faced with opportunity and challenges.

In vitro and in vivo studies on a novel solid dispersion of repaglinide using polyvinylpyrrolidone as the carrier.

In order to improve the dissolution and absorption of the water insoluble drug repaglinide, a solid dispersion was developed by solvent method using polyvinylpyrrolidone K30 (PVP K30) as the hydrophilic carrier for the first time. Studies indicated that both solubility and the dissolution rate of repaglinide were significantly increased in the solid dispersion system compared with that of repaglinide raw material or physical mixtures. The repaglinide solid dispersions with PVP K30 solid state was characterized by polarizing microscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). DSC and XRD studies indicated that repaglinide existed in an amorphous form in the solid dispersion. FT-IR analysis demonstrated the presence of intermolecular hydrogen bonding between repaglinide and PVP K30 in the solid dispersion. In the in situ gastrointestinal perfusion experiment, solid dispersion was shown to remarkably enhance the absorption of repaglinide in stomach and all segments of intestine. In vivo pharmacokinetic study in rats showed that immediate and complete release of repaglinide from the solid dispersion resulted in rapid absorption that significantly increased the bioavailability and the maximum plasma concentration over repaglinide raw material. These results demonstrated PVP K30 was an appropriate carrier for solid dispersion of repaglinide, with increased dissolution and oral absorption.

In vitro and in vivo evaluation of levofloxacin sustained-release capsules.

OBJECTIVE: To reduce the frequency of administration and improve patient compliance, novel levofloxacin sustained-release capsules with suitable in vitro release profiles and good bioavailability were developed. MATERIALS AND METHODS: A fluidized bed was used to prepare levofloxacin pellets by spraying the drug solution onto blank pellets. Then the pellets were coated with either Surelease water dispersion or Eudragit® NE30D water dispersion to achieve sustained-release characteristics. The mixed pellets containing 15% of the uncoated pellets and 85% of the coated pellets were filled into the hard gelatin capsules. In vitro release test was performed with the capsules. A single-dose pharmacokinetic study of the capsules was carried out in beagle dogs. RESULTS: Although Eudragit® NE30D-coated pellets and Surelease-coated pellets showed similar sustained-release profiles in vitro, their in vivo pharmacokinetic characteristics exhibited significant difference. Unsuccessful in vivo-in vitro correlation was shown in Eudragit® NE30D-coated pellets with a relative bioavailability of only 41.5%, whereas Surelease-coated pellets achieved best sustained-release feature both in vitro and in vivo with a relative bioavailability of 103.0%. CONCLUSION: Statistical analysis indicated that the capsules containing Surelease-coated pellets had a satisfactory sustained-release behavior and a desired pharmacokinetic property.

[Effects of 2-n-nonyl-1,3-dioxolane as an enhanceron transdermal absorption of Salvia miltiorrhiza gel].

OBJECTIVE: To choose the most suitable concentration of 2-n-nonyl-1,3-dioxolane as a penetration enhancer in tanshinone gel preparation. METHOD: In vitro, transdermal absorption was studied using improved Frans equipment and rats skin. Tanshinone II A was tested by HPLC. RESULT: The 4.0% concentration of 2-n-nonyl-1,3-dioxolane enhanced the transdermal absorption significantly in the preparation. CONCLUSION: 2-n-nonyl-1,3-dioxolane was a new effective permeaton enhancer.