[In vivo distribution of FITC-labeled boanmycin hydrochloride in situ gel].

This study is to evaluate the sustained-release effect of the thermosensitive in situ gel for injection of boanmycin hydrochloride (BAM) by bioluminescence imaging in nude mice. BAM was labeled with fluorescein isothiocyanate (FITC). The FITC-labeled BAM (FITC-BAM) was purified by dialysis and Sephadex G25 gel column, and then was identified by matrix-assisted laser desorption ionization/time of flight (MALDI-TOF). The model of experimental hepatoma HepG-2 nude mice was established, and the optical imaging system was applied to evaluate the distribution of FITC-BAM in vivo. Results of MALDI-TOF proved that the major molecular ratio of BAM : FITC was 1 : 1 or 1 : 2. Bioluminescence imaging showed that the diffusion of FITC-BAM in situ gel group was significantly delayed compared with the negative control group. This study demonstrated that the thermosensitive in situ gel can effectively delay the release of boanmycin hydrochloride, and extend the retention time in vivo.

[Thermosensitive in situ gel of boanmycin hydrochloride for injection].

Poloxamer F127, poloxamer F68 and hydroxypropyl methylcellulose K4M were used to prepare the thermosensitive in situ gel of boanmycin hydrochloride for injection. Its gelation temperature, rheological behavior, texture characteristics, scanning electron microscopy, in vitro and in vivo drug release were evaluated. These results showed that the formulation was a fluid solution at room temperature, which could become semisolid at the temperature of 37 degrees C, and the thermally induced sol-gel transition allowed to be injectable and in situ setting. The formulation was constructed into a tridimensional network at gelation temperature. The drug release was controlled by the diffusion of the drug and the erosion of the gelmatrix. The pharmacokinetics indicated that the drug could be released slowly for up to 48 hours after subcutaneous administration in rats.

Effect of peritumoral injection of boanmycin hydrochloride within temperature-sensitive in situ gel using Hep-G2 hepatoma nude mice model.

BACKGROUND: Boanmycin hydrochloride, a new antitumor agent, has a short half-life and fast clearance speed in vivo. The aim of this research was to investigate the effectiveness of peritumor injection of boanmycin hydrochloride within temperature-sensitive gel in situ using Hep-G2 hepatoma nude mice model. METHODS: Nude mice with human Hep-G2 tumor in right flank were randomly divided into four groups: normal saline group, in situ gel only group, boanmycin hydrochloride in situ saline group, and boanmycin hydrochloride in situ gel group, and were treated with injection of corresponding agents into peripheral tissue of the tumor. The volume of the tumor and the body weight of the mice were regularly measured, and tumor growth curve was generated. The size, internal echo, and blood flow of the tumors were observed by color Doppler ultrasonography. Histopathologic changes of the tumor after treatment were observed under both optical and transmission electron microscopy. RESULTS: The tumor growth was significantly inhibited by peritumoral therapy in boanmycin hydrochloride in situ gel group with the tumor inhibitory rate of 86.76%. The blood flow of the tumor was still seen in both normal saline group and in situ gel only group on color Doppler ultrasound. Punctate calcification and dotted blood flow were seen in boanmycin hydrochloride group; however, there was massive calcification and no blood flow in the tumor in the boanmycin hydrochloride in situ gel group. Large areas of necrosis and apoptotic cells were shown by microscopic observation in boanmycin hydrochloride in situ gel group. CONCLUSION: Temperature-sensitive boanmycin hydrochloride in situ gel can effectively delay the release of boanmycin hydrochloride and increase its anticancer effects for liver cancer in animal model.