Mucoadhesive polymers: Synthesis and in vitro characterization of thiolated poly(vinyl alcohol)

详细信息    查看全文

• 作者：Wongsakorn Suchaoin^a ; Irene Pereira de Sousa^a ; Kesinee Netsomboon^a ; Julia Rohrer^a ; Patricia Hoffmann Abad^a ; Flavia Laffleur^a ; Barbara Matuszczak^b ; Andreas Bernkop-Schnü ; rch^a ; ^{andreas.bernkop@uibk.ac.at" class="auth_mail" title="E-mail the corresponding author} ; ^{a.bernkop@thiomatrix.com" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Disulfide bonds ; 3-Mercaptopropionic acid ; Mucoadhesion ; Poly(vinyl alcohol) ; Thiolated polymers ; Thiourea
• 刊名：International Journal of Pharmaceutics
• 出版年：2016
• 出版时间：30 April 2016
• 年：2016
• 卷：503
• 期：1-2
• 页码：141-149
• 全文大小：923 K

文摘

The aim of this study was to synthesize thiolated poly(vinyl alcohol) (PVA) and to evaluate its mucoadhesive properties. Thiourea and 3-mercaptopropionic acid were utilized in order to obtain thiolated PVAs, namely, TPVA₁ and TPVA₂, respectively. TPVA₁ and TPVA₂ displayed 130.44 ± 14.99 and 958.35 ± 155.27 μmol immobilized thiol groups per gram polymer, respectively, which were then evaluated regarding reactivity of thiol groups, swelling behavior and mucoadhesive properties. Both thiolated PVAs exhibited the highest reactivity at pH 8.0 whereas more than 95% of free thiol groups were preserved at pH 5.0. Thiolation of PVA decelerated water uptake and prolonged disintegration time of test discs compared to unmodified PVA. Contact time of TPVA₁- and TPVA₂-based test discs on porcine intestinal mucosa was 3.2- and 15.8-fold prolonged, respectively, in comparison to non-thiolated PVA as measured by rotating cylinder method. According to tensile studies on mucosa, the total work of adhesion (TWA) and the maximum detachment force (MDF) were increased when compared to PVA. Furthermore, thiolated PVAs preserved higher percentage of viable cells compared to unmodified PVA within 24 h as evaluated by MTT assay. Accordingly, thiolated PVA represents a novel excipient that can likely improve the mucoadhesive properties of various pharmaceutical formulations.