Oliveira Renata Nunes, Meleiro Luiz Augusto da Cruz, Quilty Brid, McGuinness Garrett Brian
Chemical Engineering Department, Institute of Technology, Federal Rural University of Rio de Janeiro, Rio de Janeiro, Brazil.
School of Biotechnology, Dublin City University, Dublin, Ireland.
Front Bioeng Biotechnol. 2024 Aug 6;12:1406336. doi: 10.3389/fbioe.2024.1406336. eCollection 2024.
PVA hydrogels present many characteristics of the ideal dressing, although without antimicrobial properties. The present work aims to study the physical, mechanical and release characteristics of hydrogel wound dressings loaded with either of two natural herbal products, sage extract and dragon's blood.
Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and tensile mechanical testing were used to investigate the structure and properties of the gels. Swelling and degradation tests were conducted according to ISO 10993-9. Release characteristics were studied using UV Spectrophotometry.
PVA matrices incorporating sage extract or dragon's blood (DB) present hydrogen bonding between these components. PVA-CMC hydrogels containing sage present similar spectra to PVA-CMC alone, probably indicating low miscibility or interaction between the matrix and sage. The opposite is found for DB, which exhibits more pronounced interference with crystallinity than sage. DB and NaCMC negatively affect Young's modulus and failure strength. All samples appear to reach equilibrium swelling degree (ESD) in 24 h. The addition of DB and sage to PVA increases the gels' swelling capacity, indicating that the substances likely separate PVA chains. The inclusion of CMC contributes to high media uptake. The kinetics profile of media uptake for 4 days is described by a power-law model, which is correlated to the drug delivery mechanism.
A PVA-CMC gel incorporating 15% DB, the highest amount tested, shows the most favorable characteristics for flavonoid delivery, as well as flexibility and swelling capacity.
聚乙烯醇（PVA）水凝胶具有理想敷料的许多特性，尽管没有抗菌性能。本研究旨在探讨负载两种天然草药产品（鼠尾草提取物和血竭）之一的水凝胶伤口敷料的物理、机械和释放特性。
采用傅里叶变换红外光谱（FTIR）、差示扫描量热法（DSC）和拉伸力学测试来研究凝胶的结构和性能。根据ISO 10993-9进行溶胀和降解测试。使用紫外分光光度法研究释放特性。
掺入鼠尾草提取物或血竭（DB）的PVA基质在这些成分之间存在氢键。含鼠尾草的PVA-羧甲基纤维素（CMC）水凝胶呈现出与单独的PVA-CMC相似的光谱，这可能表明基质与鼠尾草之间的混溶性或相互作用较低。而DB的情况则相反，它对结晶度的干扰比鼠尾草更明显。DB和NaCMC对杨氏模量和断裂强度有负面影响。所有样品似乎在24小时内达到平衡溶胀度（ESD）。向PVA中添加DB和鼠尾草会增加凝胶的溶胀能力，表明这些物质可能会分离PVA链。加入CMC有助于提高对介质的吸收。介质吸收4天的动力学曲线由幂律模型描述，该模型与药物递送机制相关。
掺入15%DB（测试的最高含量）的PVA-CMC凝胶在黄酮类化合物递送、柔韧性和溶胀能力方面表现出最有利的特性。
