Limitations of the rheological mucoadhesion method:: The effect of the choice of conditions and the rheological synergism parameter
Limitations of the rheological mucoadhesion method:: The effect of the choice of conditions and the rheological synergism parameter
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DOI：
10.1016/s0928-0987(03)00037-x
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发表时间：
2003-04-01
影响因子：
4.6
通讯作者：
Edsman, K
中科院分区：
文献类型：
--
作者：
Hägerström, H;Edsman, K
这项工作证明了广泛用于研究聚合物凝胶黏附的简单流变学方法的几个局限性。我们确立了条件选择和协同效应参数对比较研究结果的重要性。采用四种略有不同的聚丙烯酸（Carbopol）聚合物及其与猪胃粘蛋白和牛颌下腺粘蛋白的混合物，对凝胶进行了动态流变学测量。聚合物比较的基本原理对得到的结果有很大的影响。当使用两种不同的比较策略时，该方法不会给出相同的排序顺序。此外，我们表明，所获得的结果对在“流变范围”中进行比较的位置也很敏感，例如，在哪个值G'。例如，只有在弱凝胶中才能看到增效参数的正值。增效参数的选择也对所得结果有影响，在这里我们提出了一个新的精炼相对参数，即对数比(log（G′（mix)/G(p)′））。我们还研究了凝胶制剂与猪鼻黏膜的粘附性，采用拉伸强度测量。凝胶强度的增加导致了更强的粘附，这与流变学方法的结果相反，在流变学方法中，只有在弱凝胶中才能看到协同作用参数的正值。基于所证明和讨论的局限性，我们建议流变学方法不应作为研究聚合物凝胶粘接特性的独立方法。(C) 2003 Elsevier Science B.V.版权所有
This work demonstrates several limitations of the simple rheological method that is widely used to investigate mucoadhesion of polymer gels. We establish the importance of the choice of conditions and the synergism parameter for the results obtained in comparative studies. Dynamic rheological measurements were performed on gels based on four slightly different poly(acrylic acid) (Carbopol) polymers and their corresponding mixtures with porcine stomach mucin and bovine submaxillary gland mucin. The rationale for the comparison of the polymers had a large influence on the results obtained. The method does not give the same ranking order when two different comparison strategies are used. Moreover, we show that the results obtained are also sensitive to where in the 'rheological range' the comparison is made, e.g., at which value of G'. Positive values of the synergism parameters are, for example, only seen with weak gels. The choice of synergism parameter also has a bearing on the results obtained, and here we suggest a new refined relative parameter, the log ratio (log(G'(mix)/G(p)')). We also investigated the adhesion of the gel preparations to porcine nasal mucosa, using tensile strength measurements. Increased gel strength resulted in stronger adhesion, which is in contrast to the results from the rheological method, where the positive values of the synergism parameters were seen only with weak gels. On the basis of the limitations demonstrated and discussed, we recommend that the rheological method should not be used as a stand-alone method for the studying of mucoadhesive properties of polymer gels. (C) 2003 Elsevier Science B.V. All rights reserved.