School of Pharmacy, Pharmaceutical Technology, Faculty of Health Sciences, University of Eastern Finland, 70211 Kuopio, Finland.
Pharmaceutics. 2011 Jun 21;3(2):315-25. doi: 10.3390/pharmaceutics3020315.
Porous silicon (PSi) is an innovative inorganic material that has been recently developed for various drug delivery systems. For example, hydrophilic and hydrophobic PSi microparticles have been utilized to improve the dissolution rate of poorly soluble drugs and to sustain peptide delivery. Previously, the well-plate method has been demonstrated to be a suitable in vitro dissolution method for hydrophilic PSi particles but it was not applicable to poorly wetting hydrophobic thermally hydrocarbonized PSi (THCPSi) particles. In this work, three different in vitro dissolution techniques, namely centrifuge, USP Apparatus 1 (basket) and well-plate methods were compared by using hydrophilic thermally carbonized PSi (TCPSi) microparticles loaded with poorly soluble ibuprofen or freely soluble antipyrine. All the methods showed a fast and complete or nearly complete release of both model compounds from the TCPSi microparticles indicating that all methods described in vitro dissolution equally. Based on these results, the centrifuge method was chosen to study the release of a peptide (ghrelin antagonist) from the THCPSi microparticles since it requires small sample amounts and achieves good particle suspendability. Sustained peptide release from the THCPSi microparticles was observed, which is in agreement with an earlier in vivo study. In conclusion, the centrifuge method was demonstrated to be a suitable tool for the evaluation of drug release from hydrophobic THCPSi particles, and the sustained peptide release from THCPSi microparticles was detected.
多孔硅（PSi）是一种新型无机材料，最近已被开发用于各种药物传递系统。例如，亲水性和疏水性 PSi 微球已被用于提高难溶性药物的溶解速率，并维持肽类药物的传递。以前，平板法已被证明是一种适用于亲水性 PSi 颗粒的体外溶解方法，但不适用于疏水性热碳化 PSi（THCPSi）颗粒的润湿。在这项工作中，使用负载难溶性布洛芬或自由溶解的安替比林的亲水性热碳化 PSi（TCPSi）微球比较了三种不同的体外溶解技术，即离心、USP 装置 1（篮）和平板法。所有方法均显示两种模型化合物均从 TCPSi 微球中快速且完全或几乎完全释放，表明所有体外溶解方法均等效。基于这些结果，选择离心法来研究肽（胃饥饿素拮抗剂）从 THCPSi 微球中的释放，因为它需要少量样品并且可以实现良好的颗粒悬浮性。从 THCPSi 微球中观察到肽的持续释放，这与早期的体内研究一致。总之，离心法已被证明是评估疏水性 THCPSi 颗粒中药物释放的合适工具，并检测到 THCPSi 微球中肽的持续释放。
