Applicability of low-melting-point microcrystalline wax to develop temperature-sensitive formulations

作者：Matsumoto Kohei; Kimura Shin ichiro; Iwao Yasunori; Itai Shigeru^*

来源：International Journal of Pharmaceutics, 2017, 532(1): 528-536.

DOI：10.1016/j.ijpharm.2017.09.038

• Wax matrix
• Microcrystalline wax
• Acetaminophen
• Temperature-sensitive release formulations
• Spray congealing technique

Low-melting-point substances are widely used to develop temperature-sensitive formulations. In this study, we focused on microcrystalline wax (MCW) as a low-melting-point substance. We evaluated the drug release behavior of wax matrix (WM) particles using various MCW under various temperature conditions. WM particles containing acetaminophen were prepared using a spray congealing technique. In the dissolution test at 37 degrees C, WM particles containing low-melting-point MCWs whose melting was starting at approx. 40 degrees C (Hi-Mic-1045 or 1070) released the drug initially followed by the release of only a small amount. On the other hand, in the dissolution test at 20 and 25 degrees C for WM particles containing Hi-Mic-1045 and at 20, 25, and 30 degrees C for that containing Hi-Mic-1070, both WM particles showed faster drug release than at 37 degrees C. The characteristic drug release suppression of WM particles containing low-melting-point MCWs at 37 degrees C was thought attributable to MCW melting, as evidenced by differential scanning calorimetry analysis and powder X-ray diffraction analysis. Taken together, low-melting-point MCWs may be applicable to develop implantable temperature-sensitive formulations that drug release is accelerated by cooling at administered site.

• 出版日期2017-10-30