El-Shafy M A, Kellaway I W, Taylor G, Dickinson P A
The Welsh School of Pharmacy, Cardiff University, UK.
J Drug Target. 2000;7(5):355-61. doi: 10.3109/10611869909085518.
The nasal bioavailability of fluorescein isothiocyanate-dextran (FITC-dextran) (Mw = 4300) encapsulated in non-mucoadhesive and mucoadhesive microspheres in New Zealand White rabbits was investigated. FITC-dextran was administered nasally encapsulated in carbopol 934P, chitosan and lactose microspheres and the bioavailability compared to intravenous administration of FITC-dextran solution. Administration of FITC-dextran as carbopol microspheres produced a significantly greater bioavailability (33%) than after administration as chitosan (13%) and non-mucoadhesive rapidly dissolving control lactose microspheres (9%). The FITC-dextran terminal plasma half-lives after carbopol 934P and chitosan microsphere administration were significantly longer than after intravenous administration of FITC-dextran. The FITC-dextran terminal plasma half-life after carbopol 934P microspheres administration was significantly longer than after lactose microsphere administration. This data suggested that the increase in FITC-dextran bioavailability after carbopol 934P microspheres administration was due to increased residence at the absorptive site via mucoadhesion and reduced mucociliary clearance. A change in mucosal permeability could not however be discounted especially for the chitosan microspheres.
研究了新西兰白兔鼻腔给予包裹在非黏膜黏附性和黏膜黏附性微球中的异硫氰酸荧光素 - 葡聚糖（FITC - 葡聚糖）（分子量 = 4300）后的生物利用度。将FITC - 葡聚糖包裹在卡波姆934P、壳聚糖和乳糖微球中经鼻腔给药，并与静脉注射FITC - 葡聚糖溶液后的生物利用度进行比较。以卡波姆微球形式给予FITC - 葡聚糖产生的生物利用度（33%）显著高于以壳聚糖（13%）和非黏膜黏附性快速溶解的对照乳糖微球（9%）形式给药后的生物利用度。给予卡波姆934P和壳聚糖微球后，FITC - 葡聚糖的血浆终末半衰期显著长于静脉注射FITC - 葡聚糖后的半衰期。给予卡波姆934P微球后，FITC - 葡聚糖的血浆终末半衰期显著长于给予乳糖微球后的半衰期。该数据表明，给予卡波姆934P微球后FITC - 葡聚糖生物利用度的增加是由于通过黏膜黏附增加了在吸收部位的停留时间以及减少了黏液纤毛清除率。然而，不能排除黏膜通透性的变化，特别是对于壳聚糖微球。
