Li C, Bhatt P P, Johnston T P
Division of Pharmaceutics and Pharmacodynamics, College of Pharmacy, University of Illinois, Chicago 60612, USA.
Drug Dev Ind Pharm. 1998 Oct;24(10):919-26. doi: 10.3109/03639049809097271.
We have assessed the bioadhesive properties of several different mucoadhesive buccal patches. The patches consisted of custom coformulations of silicone polymers and Carbopol 974P. The contact angle of water was measured for each of the test formulations, using an ophthalmic shadow scope. The corresponding work of adhesion between the water and the patches (W1), and between the patches and freshly-excised rabbit buccal mucosa (W2) was then calculated, using a modification of Dupre's equation. The bioadhesive strength between the patches and excised rabbit buccal mucosa was also assessed. The results of the contact-angle measurements indicated that the contact angle decreased with an increase in the amount of Carbopol in the formulation. Additionally, the calculated values of both W1 and W2 increased with an increase in the amount of Carbopol in the buccal-patch formulations. A correlation (r not equal to 0.9808) was found between the measured contact angle and the calculated values for W2. The direct measurement of the force required to separate a buccal patch from excised rabbit buccal mucosa with the INSTRON demonstrated that the adhesive strength increased with an increase in the amount of Carbopol. This preliminary study has shown that the measurement of contact angles alone may provide a useful technique for estimating the work of adhesion, and may serve as a convenient and rapid screening procedure to identify potential mucoadhesive buccal-patch formulations.
我们评估了几种不同的黏膜黏附性口腔贴片的生物黏附特性。这些贴片由有机硅聚合物和卡波姆974P的定制共混物组成。使用眼科阴影镜测量了每种测试制剂的水接触角。然后，使用杜普雷方程的修正形式，计算了水与贴片之间（W1）以及贴片与新鲜切除的兔颊黏膜之间（W2）的相应黏附功。还评估了贴片与切除的兔颊黏膜之间的生物黏附强度。接触角测量结果表明，制剂中卡波姆含量增加时，接触角减小。此外，颊部贴片制剂中卡波姆含量增加时，W1和W2的计算值均增加。在测量的接触角与W2的计算值之间发现了相关性（r不等于0.9808）。使用英斯特朗仪器直接测量将口腔贴片从切除的兔颊黏膜上分离所需的力，结果表明黏附强度随卡波姆含量的增加而增加。这项初步研究表明，仅测量接触角可能为估算黏附功提供一种有用的技术，并且可以作为一种方便快捷的筛选程序，以识别潜在的黏膜黏附性口腔贴片制剂。
