Research Laboratory of Carbohydrates and Biopolymers, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
J Pharm Pharm Sci. 2011;14(2):162-80. doi: 10.18433/j3zc73.
A simple type of photoresponsive amphiphilic linear-dendritic diblock copolymer has been synthesized and investigated for its ability to act as a drug carrier. These structures contain hydrophilic polyethylene oxide monomethyl ether (PEOM) as hydrophilic block and carbosiloxane dendritic branches as hydrophobic block grafted by two and six Magneson II as azo chromophore, PEOM-Azo, 2 and PEOM-Azo, 6 respectively. Self-assembling of the amphiphilic macromolecules of PEOM-Azo, 2 and PEOM-Azo, 6, briefly were represented as PEOM-Azo [2, 6], leads to the formation of their micellar aggregates in aqueous media.
Their micellar properties such as critical micelle concentration (CMC), aggregation number and thereby total numbers of azo-groups in each micellar aggregates were determined. Also, they were characterized by TEM, SEM and DLS.
The unloaded aggregates examined under UV light (366 nm), which were observed to be smaller than 300 nm. The release patterns of the encapsulated drug molecule from these aggregates were investigated as regulated by the PEOM-Azo [2, 6] systems in trans and cis forms.
A comparison of the release behavior of the loaded PEOM-Azo [2, 6] systems indicated that the release rate of the encapsulated active molecules from the carriers was slower when the azo moieties were in trans form as compared to that the azo in the cis form. The in vitro release behavior of drug from these polymeric systems represents potential of the carriers for controlled drug delivery.
合成了一种简单的光响应两亲性线性树枝状嵌段共聚物,并研究了其作为药物载体的能力。这些结构包含亲水性聚乙二醇单甲醚(PEOM)作为亲水性嵌段和碳硅氧烷树枝状支链作为疏水性嵌段,通过两个和六个 Magneson II 作为偶氮发色团接枝,分别为 PEOM-Azo,2 和 PEOM-Azo,6。两亲性大分子 PEOM-Azo,2 和 PEOM-Azo,6 的自组装,简要表示为 PEOM-Azo [2,6],导致其胶束聚集体在水介质中的形成。
测定了其胶束性质,如临界胶束浓度(CMC)、聚集数以及每个胶束聚集体中的偶氮基团总数。此外,还通过 TEM、SEM 和 DLS 进行了表征。
在紫外光(366nm)下检查未负载的聚集体,发现其小于 300nm。研究了这些聚集体中未封装药物分子的释放模式,这些聚集体受 PEOM-Azo [2,6] 系统顺式和反式的调节。
比较负载的 PEOM-Azo [2,6] 系统的释放行为表明,与偶氮部分处于顺式形式相比,载体中封装的活性分子的释放速度较慢。这些聚合物系统中药物的体外释放行为表明载体具有潜在的控制药物释放能力。