Delavirdine mesylate 是在愛滋病治療過程中使用的 HIV-1 的非核苷反轉錄   抑 制劑。Delavirdine 是非常脂溶且其水溶解度極低。本研究的目的是在評估以平衡透 析法測定 delavirdine 的血漿蛋白結合之適用性，並探討 delavirdine 與血漿蛋白結合 之特性。Delavirdine 在人和狗的血漿蛋白結合乃是以平衡透析法測定。血漿樣品 (0.75 mL)與等體積的等張磷酸鹽緩衝液(0.067 M，pH 7.4)在 37oC  下進行平衡透析。 試驗結果顯示藥物濃度低於 200  µg/mL 時，透析可在 6 小時達到平衡。Delavirdine 的血漿蛋白結合程度隨其藥物濃度的增加而減少，且可用單一種類結合部位的蘭米 爾方程式來解析其血漿蛋白結合數據。Delavirdine 的血漿蛋白結合率在藥物濃度低 於 50 µg/mL 時呈線性，其平均未結合率約為 0.015。本研究所使用之平衡透析法與 條件經過確認，可適用於測量含藥高達 200  µg/mL 的臨床血漿樣品中 delavirdine 之 血漿蛋白結合程度。
 

Purpose. Delavirdine mesylate is a non-nucleoside reverse transcriptase inhibitor of HIV-1 used in AIDS therapy. Delavirdine is highly lipophilic and has poor aqueous
solubility. The objectives of this study were to investigate the suitability of equilibrium dialysis for the determination of plasma protein binding of delavirdine, and to explore the binding characteristics of delavirdine. Methods. The binding of delavirdine to human and dog plasma proteins was determined using equilibrium dialysis method. Plasma samples (0.75 mL) were dialyzed against an equal volume of isotonic phosphate buffer (0.067 M, pH 7.4) at 37°C. Results. Equilibrium can be reached at 6 hours for concentrations up to 200 μg/mL. The extent of binding decreased with increasing drug concentration. The Langmuir equation with a single class of binding sites fit the data well. Linear protein binding was evident up to approximately 50 μg/mL with an average unbound fraction of approximately 0.015. Conclusions. Validation of a suitable equilibrium dialysis method for plasma protein binding is, thus, provided for clinical plasma samples of delavirdine with concentration up to 200 μg/mL.