Bujard Alban, Voirol Hervé, Carrupt Pierre-Alain, Schappler Julie
School of Pharmaceutical Sciences, EPGL, University of Geneva, 30 Quai Ernest Ansermet, CH 1211 Geneva 4, Switzerland.
School of Pharmaceutical Sciences, EPGL, University of Geneva, 30 Quai Ernest Ansermet, CH 1211 Geneva 4, Switzerland.
Eur J Pharm Sci. 2015 Sep 18;77:273-8. doi: 10.1016/j.ejps.2015.06.023. Epub 2015 Jun 25.
The Parallel Artificial Membrane Permeability Assay (PAMPA) is a well-known high throughput screening (HTS) technique for predicting in vivo passive absorption. In this technique, two compartments are separated by an artificial membrane that mimics passive permeability through biological membranes such as the dermal layer, the gastrointestinal tract (GIT), and the blood brain barrier (BBB). In the present study, a hexadecane artificial membrane (HDM)-PAMPA was used to predict the binding of compounds towards the human plasma using a mixture of human serum albumin (HSA) and alpha-1-acid glycoprotein (AGP). The ratio of HSA and AGP was equivalent to that found in the human plasma for both proteins (∼20:1). A pH gradient (5.0-7.4) was performed to increase the screening capacity and overcome the issue of passive permeability for acidic and amphoteric compounds. With this assay, the prediction of passive GIT absorption was maintained and the compounds were discriminated according to their permeability (on a no-to-high scale). The plasma protein binding (PPB) was estimated via the correlation of the differences between the amount of compound crossing the artificial membrane in assays conducted with and without protein using only a two end-point measurement. The use of a mixture of HSA and AGP to modulate drug permeation was compared to the use of the same concentrations of HSA and AGP used separately. The addition of HSA alone in the acceptor compartment was sufficient for estimating PPB, while it was demonstrated that AGP alone could enable the estimation of AGP binding.
平行人工膜通透性测定法（PAMPA）是一种用于预测体内被动吸收的著名高通量筛选（HTS）技术。在该技术中，两个隔室由一层人工膜隔开，该人工膜模拟了通过生物膜（如真皮层、胃肠道（GIT）和血脑屏障（BBB））的被动通透性。在本研究中，使用十六烷人工膜（HDM）-PAMPA，通过人血清白蛋白（HSA）和α-1-酸性糖蛋白（AGP）的混合物来预测化合物与人血浆的结合。HSA和AGP的比例与人血浆中这两种蛋白质的比例相当（约20:1）。进行了pH梯度（5.0 - 7.4）操作，以提高筛选能力并克服酸性和两性化合物的被动通透性问题。通过该测定法，维持了对GIT被动吸收的预测，并根据化合物的通透性（从无到高）对其进行区分。仅通过两个终点测量，利用在有蛋白和无蛋白情况下通过人工膜的化合物量的差异相关性来估计血浆蛋白结合（PPB）。将使用HSA和AGP混合物调节药物渗透与分别使用相同浓度的HSA和AGP进行了比较。在受体隔室中单独添加HSA足以估计PPB，同时已证明单独使用AGP能够估计AGP结合。
