為了能較持久的傳遞藥物,減少用藥頻率,降低血藥濃度的峰谷現象,提高藥效和安全性,近年來人們常將藥物制成緩、控釋劑,如緩釋骨架片、膜控釋包衣片、微球、微囊等。其中,表面活性劑的應用范圍得到進(jin)一(yi)步拓寬。
表面(mian)活性劑與其它骨(gu)架材(cai)料(liao)混合(he)(he)使用(yong)(yong),可以控制(zhi)釋藥速率,降低藥物(wu)的副(fu)作用(yong)(yong)。如:氨茶堿(jian)緩釋片(pian)采(cai)用(yong)(yong)非離子表面(mian)活性劑單(dan)硬脂酸甘油酯和微晶纖維(wei)素混合(he)(he)作為生(sheng)物(wu)溶(rong)蝕性骨(gu)架材(cai)料(liao),采(cai)用(yong)(yong)熱熔法制(zhi)成,延長了氨茶堿(jian)療(liao)效,減輕了惡心(xin)、嘔吐(tu)等副(fu)作用(yong)(yong)。
在生物(wu)(wu)溶(rong)(rong)(rong)蝕(shi)性(xing)骨(gu)架片中,表(biao)面(mian)(mian)(mian)(mian)活(huo)性(xing)劑(ji)對藥物(wu)(wu)的(de)釋放有一定影響,釋藥速(su)率隨表(biao)面(mian)(mian)(mian)(mian)活(huo)性(xing)劑(ji)水中溶(rong)(rong)(rong)解度(du)(du)增(zeng)(zeng)大(da)(da)而加(jia)(jia)(jia)快。如(ru)(ru):鹽酸去敏靈的(de)巴西棕櫚臘,在硬(ying)脂(zhi)(zhi)(zhi)醇溶(rong)(rong)(rong)蝕(shi)片中如(ru)(ru)加(jia)(jia)(jia)入不溶(rong)(rong)(rong)性(xing)表(biao)面(mian)(mian)(mian)(mian)活(huo)性(xing)劑(ji)單硬(ying)脂(zhi)(zhi)(zhi)酸甘油酯,則(ze)不影響藥物(wu)(wu)釋放速(su)率;加(jia)(jia)(jia)入微溶(rong)(rong)(rong)或溶(rong)(rong)(rong)解緩慢的(de)表(biao)面(mian)(mian)(mian)(mian)活(huo)性(xing)劑(ji)如(ru)(ru)硬(ying)脂(zhi)(zhi)(zhi)酸鈉、硬(ying)脂(zhi)(zhi)(zhi)酸胺等,則(ze)中等程(cheng)度(du)(du)增(zeng)(zeng)加(jia)(jia)(jia)藥物(wu)(wu)釋放;如(ru)(ru)加(jia)(jia)(jia)入水溶(rong)(rong)(rong)性(xing)的(de)聚(ju)氧乙烯23-月(yue)桂(gui)醚則(ze)相當大(da)(da)程(cheng)度(du)(du)地增(zeng)(zeng)加(jia)(jia)(jia)藥物(wu)(wu)溶(rong)(rong)(rong)解度(du)(du)。
為增加(jia)制劑(ji)的親水性(xing)(xing),改(gai)善藥物吸(xi)收,提高生物利用度(du),可加(jia)入(ru)親水性(xing)(xing)表面活(huo)性(xing)(xing)劑(ji)。如(ru):在呋喃酮胃漂(piao)浮片中加(jia)入(ru)陰離子表面活(huo)性(xing)(xing)劑(ji)月桂醇硫酸鈉作為潤濕劑(ji),該(gai)制劑(ji)在人胃內滯留時(shi)間為4小時(shi)~6小時(shi),明顯長于普通片劑(ji)。
為了提高胃內滯留片滯留能力,可在制劑中添加密度相對小的疏水性表面活性劑烷基糖苷。如:在(zai)地(di)西泮胃內(nei)漂浮(fu)控釋(shi)片(pian)中添加單(dan)硬脂酸甘(gan)油酯(zhi)作為阻(zu)滯(zhi)劑(ji),采用粉末直接壓片(pian)法制得,藥物體外釋(shi)放(fang)時間顯著(zhu)延(yan)長,體內(nei)吸收AUC為普通(tong)片(pian)的2倍(bei)。
非離子表面活(huo)性劑泊洛沙(sha)姆-407是(shi)一種新型的藥物緩釋材料,毒(du)性低(di),生物相容性好,在(zai)低(di)溫(4℃)條(tiao)件下(xia)為流動的液(ye)體(ti),在(zai)人體(ti)溫范圍內則迅速形(xing)成(cheng)固體(ti)軟(ruan)凝膠。以其為載體(ti),將(jiang)抗癌藥去(qu)甲斑蝥素制成(cheng)注射用(yong)(yong)緩釋劑使用(yong)(yong),能起到(dao)減(jian)毒(du)增效作用(yong)(yong),且泊洛沙(sha)姆-407濃度(du)與去(qu)甲斑螫(shi)素體(ti)外釋放度(du)呈線性負相關。