Fransén Nelly, Björk Erik, Edsman Katarina
Department of Pharmacy, Uppsala University, PO Box 580, SE-751 23 Uppsala, Sweden.
J Pharm Sci. 2008 Sep;97(9):3855-64. doi: 10.1002/jps.21279.
The residence time in the nasal cavity can be prolonged by dry particles that absorb water and subsequently increase the viscosity of the mucus layer. A novel nasal drug delivery system based on interactive mixtures has previously been developed, where fine particles of the active component are adhered to the surface of mucoadhesive carrier particles by dry mixing. The surface coverage may alter the original mucoadhesiveness of the carrier particles and to investigate this, a simplified tensile strength method was developed and evaluated. Reliable results were obtained with a plastic coated absorbent paper covered by a mucin solution as a substitution for porcine nasal mucosa and should also be applicable to other dry particle systems. The method showed that the swelling of sodium starch glycolate particles was slightly delayed, corresponding to the degree of hydrophobic surface coverage. Carrier particles of partly pregelatinized maize starch were not influenced by the addition of a hydrophobic substance, probably because of the rough particle shape that inhibited a complete surface coverage. It was concluded that the surface coverage of carrier particles in interactive mixtures only could cause a short delay in water absorption that should not affect their mucoadhesive characteristics in vivo.
鼻腔中的停留时间可通过吸收水分并随后增加黏液层黏度的干燥颗粒来延长。此前已开发出一种基于交互式混合物的新型鼻腔给药系统，其中活性成分的细颗粒通过干混附着在黏膜黏附载体颗粒的表面。表面覆盖率可能会改变载体颗粒的原始黏膜黏附性，为对此进行研究，开发并评估了一种简化的拉伸强度方法。以覆盖有黏蛋白溶液的塑料涂层吸水纸替代猪鼻黏膜可获得可靠结果，该方法也应适用于其他干燥颗粒系统。该方法表明，羟丙基淀粉钠颗粒的溶胀略有延迟，这与疏水表面覆盖率的程度相对应。部分预胶化玉米淀粉的载体颗粒不受疏水性物质添加的影响，这可能是由于颗粒形状粗糙，阻碍了完全的表面覆盖。得出的结论是，交互式混合物中载体颗粒的表面覆盖只会导致吸水略有延迟，这不应该影响它们在体内的黏膜黏附特性。
