Gelatin microspheres (GMs) containing
Pingyangmycin hydrochloride were prepared for the interventional embolization by a double-phase emulsified thermal gelation method using oxidized
dextran (ox-dex) as the cross-linking agent. The average diameter of the
microspheres was 82 microm with 74% ranging from 50-200 microm.
Drug content and the characteristics of drug release in vitro and in vivo were evaluated using UV-spectroscopy and HPLC, respectively. The prepared
microspheres showed a rather high percentage of encapsulation ranging from 85 to 88% and
drug content at 7.2%. The results of in vitro experiments showed that about 65.5% of the total amount of the encapsulated
drug was released after 6 h at 37 degrees C. Experiments conducted through artery perfusion and artery embolization in rabbits revealed that the local
drug concentration was significantly higher than the systemic blood-
drug concentration, with a high level of local
drug concentration maintained for more than 120 min after artery embolization with the
Pingyangmycin-loaded ox-dex-GMs. The results indicated that the external carotid artery embolization with
Pingyangmycin-loaded ox-dex-GMs at reduced dosages prolonged the local
drug concentration at a higher level, and could achieve the purpose of a localized targeting
tumor therapy. Compared with other embolization materials, ox-dex-GMs are an excellent alternative interventional embolization material for the treatment of head and neck
tumors.