Hsein Hassana, Garrait Ghislain, Beyssac Eric, Hoffart Valérie
Univ Clermont 1, UFR Pharmacie, EA4678, Laboratoire de Biopharmacie, Clermont-Ferrand F-63001, France.
Univ Clermont 1, UFR Pharmacie, EA4678, Laboratoire de Biopharmacie, Clermont-Ferrand F-63001, France.
Colloids Surf B Biointerfaces. 2015 Dec 1;136:799-808. doi: 10.1016/j.colsurfb.2015.10.016. Epub 2015 Oct 23.
Whey protein is a natural polymer recently used as an excipient in buccoadhesive tablets but its mucoadhesive properties were barely studied. In this work, we characterize mucoadhesion of whey protein in order to determine the mechanisms and optimal conditions for use as excipient in oral drug delivery. Thus, native and denatured whey protein (NWP and DWP) were investigated and the effect of concentration and pH were also studied. Many methods of characterization were selected to allow the study of chemical and physical interactions with mucin and then the results were bound with an ex vivo experiments. Turbidity of WP-mucin mixture increased at acidic pH 1.2 till 4.5 indicating interaction with mucin but not at pH 6.8. No interaction with mucin was also found by ITC method at pH 6.8 for native and denatured whey protein used at 1% (w/w). Forces of bioadhesion evaluated by viscosity measurements were the best for high concentrated (10.8%) DWP solutions at pH 6.8 and were low at pH 1.2 for NWP and DWP solutions. Addition of chemical blockers indicated that hydrogen bondings and disulfide bridges were the main mechanisms of interactions with mucin. Reticulation of DWP with calcium ions to obtain microparticles (MP) did not influence the ability of interaction with mucin as shown by FTIR analysis. These results correlated with ex vivo study on rat tissue demonstrating important adhesion (75%) of WP MP on the intestine and null on the stomach after 2h of deposit.
乳清蛋白是一种天然聚合物，最近被用作口腔黏附片的辅料，但其黏膜黏附特性鲜有研究。在本研究中，我们对乳清蛋白的黏膜黏附性进行了表征，以确定其作为口服给药辅料的作用机制和最佳条件。因此，我们研究了天然和变性乳清蛋白（NWP和DWP），并考察了浓度和pH值的影响。我们选择了多种表征方法来研究与黏蛋白的化学和物理相互作用，然后将结果与体外实验相结合。WP-黏蛋白混合物在酸性pH 1.2至4.5时浊度增加，表明与黏蛋白发生了相互作用，但在pH 6.8时没有。在pH 6.8时，ITC法也未发现1%（w/w）的天然和变性乳清蛋白与黏蛋白有相互作用。通过粘度测量评估的生物黏附力在pH 6.8时对高浓度（10.8%）的DWP溶液最佳，而在pH 1.2时对NWP和DWP溶液较低。添加化学阻滞剂表明氢键和二硫键是与黏蛋白相互作用的主要机制。FTIR分析表明，用钙离子使DWP交联以获得微粒（MP）并不影响与黏蛋白的相互作用能力。这些结果与对大鼠组织的体外研究相关，该研究表明WP MP在沉积2小时后在肠道上有重要黏附（75%），而在胃上无黏附。
