Synthesis and immobilization of micro-scale drug particles in presence of ß-cyclodextrins.

The anti-solvent synthesis in presence of cyclodextrins (CDs) of the drug Griseofulvin (GF) is presented. This was followed by immobilization into cellulosic polymer films suitable for drug delivery. The results show that 72% of the GF precipitated in presence of CD, while the rest led to the formation of a water soluble GF/CD complex. The cyclodextrins were effective in inhibiting particle growth and stabilizing the drug suspensions. Among the CDs tested here, hydroxypropyl-ß-cyclodextrin (HPBCD) was found to be most effective in reducing the particle size. The release profiles from the cyclodextrin stabilized GF particles showed improvement in release rate, which indicated effective drug/cyclodextrin interactions.

Synthesis and immobilization of micro-scale drug particles in cellulosic films.

The anti-solvent synthesis of micron-scale particles, their stabilization, and subsequent self-assembly into polymer films suitable for drug delivery is presented. The colloidal particles were stabilized using low molecular weight hydroxypropyl methylcellulose (HPMC), while drug encapsulation was carried out with high molecular weight HPMC and polyvinylpyrrolidone (PVP). Griseofulvin (GF) was used as the model drug compound, and the polymer films were evaluated in terms of their surface morphology, mechanical properties and in vitro drug release. In general, the release rates were best described by first-order and Hixson-Crowell kinetic models, and in a typical film containing 57% HPMC, 100% of GF was released within 50 min.

Stabilizing dispersions of hydrophobic drug molecules using cellulose ethers during anti-solvent synthesis of micro-particulates.

Anti-solvent synthesis of micro-scale drug particles with simultaneous suspension stabilization using different cellulose ethers and a surfactant (SDS) is reported. The process was very effective under low power ultrasonic agitation. The mean diameter of the small particles grew with time, while the overall particle size distribution showed a decrease in average particle size due to sedimentation. The result showed that a combination of cellulose ether and SDS reduced the average particle size more effectively than either only cellulose ether or SDS. The sedimentation rate was also the lowest when both the cellulose ether and SDS were used. At the end of nine hours, as much as 74.6% of the drug Fenofibrate, and 56.0% of the drug griseofulvin remained in stable suspension in drug/HPMC/SDS systems. Zeta potential measurements showed that the suspensions were close to agglomeration rather than thermodynamically stable. Melting point measurements showed that cellulose ether was not a major component of the particle, while scanning electron microscopy revealed particle shapes and degree of the agglomeration. Raman spectroscopy also confirmed the presence of the drug molecule in these crystals.

In vitro antibacterial efficacy of MONOCRYL plus antibacterial suture (Poliglecaprone 25 with triclosan).

BACKGROUND: This study evaluated the in vitro efficacy of poliglecaprone 25 suture with triclosan against gram-positive and gram-negative bacteria. METHODS: Poliglecaprone 25 sutures with and without triclosan were tested for in vitro efficacy against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, methicillin-resistant Staphylococcus epidermidis (MRSE), Klebsiella pneumoniae, and Escherichia coli by a zone of inhibition assay. The suture also was tested against Escherichia coli in a colonization assay in a dynamic model simulating in vivo conditions. An in vitro triclosan diffusion assay and a sustained efficacy assay were performed by concurrent high-performance liquid chromatography and zone of inhibition assay. To assess stability, antibacterial efficacy testing was performed on samples held more than five months at elevated temperature. RESULTS: Poliglecaprone 25 suture with triclosan demonstrated significant in vitro efficacy against a range of bacteria. The suture sustained in vitro efficacy for 11 days, corresponding to the in vitro triclosan diffusion profile. CONCLUSION: Triclosan reduced in vitro colonization of poliglecaprone 25 suture by several strains of bacteria compared with untreated control sutures.