Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Italy.
Drug Dev Ind Pharm. 2012 Aug;38(8):979-84. doi: 10.3109/03639045.2011.634812. Epub 2011 Nov 29.
Dibutyrylchitin (DBC), a lipophilic chitin diester, has been synthesized from chitin and butyric anhydride with methanesulfonic acid as catalyst. Exhaustive esterification of free alcoholic groups of chitin was assessed by FT-IR and (1)H-NMR spectroscopy. High degree of alkyl substitution allowed DBC to acquire an almost completely lipophilic character. Tablets of paracetamol and metformin employing DBC as major excipient, in comparison with starch, microcrystalline cellulose, lactose and polyvinylpyrrolidone, were prepared and rates of drug release were checked by dissolution test assays. DBC released drug at a lower rate than that of the other tested materials. A comparison study of rate release of metformin from DBC tablets and from metformin-hydroxypropyl methylcellulose prolonged release oral formulation available on the market has been also curried out. Under the same conditions and in the presence of the same amount of loaded drug, DBC released 64% of metformin whereas hypromellose-based tablets released 87%.
二丁酰基壳聚糖（DBC）是一种亲脂性的壳聚糖二酯，由壳聚糖和丁酰酐在甲磺酸作为催化剂的条件下合成得到。通过傅里叶变换红外光谱（FT-IR）和（1）H-NMR 光谱评估壳聚糖游离醇基的完全酯化程度。高烷基取代度使 DBC 几乎完全具有亲脂性。与淀粉、微晶纤维素、乳糖和聚乙烯吡咯烷酮相比，使用 DBC 作为主要赋形剂的对乙酰氨基酚和二甲双胍片剂，通过溶出度试验进行了药物释放速率的检查。DBC 的药物释放速率低于其他测试材料。还对 DBC 片剂和市售的二甲双胍-羟丙基甲基纤维素延长释放口服制剂中二甲双胍的释放速率进行了比较研究。在相同的条件下和相同的载药量下，DBC 释放了 64%的二甲双胍，而基于羟丙基甲基纤维素的片剂释放了 87%。
