Gelation behavior of in situ forming gels based on HPMC and biphasic calcium phosphate nanoparticles

• Published in: Carbohydrate polymers 2014, Vol.99, p.257-263
• Main Authors: Marefat Seyedlar, Roghayyeh, Nodehi, Azizollah, Atai, Mohammad, Imani, Mohammad
• Format: Article
• Language: English
• Subjects: Applied sciences; Biphasic calcium phosphate; Calcium phosphates nanoceramics; Chromatography, Gel; Composites; Exact sciences and technology; Forms of application and semi-finished materials; Gels; Hydrophobic and Hydrophilic Interactions; Hydroxyapatites - chemistry; Hydroxypropyl methylcellulose; Hypromellose Derivatives; Injectable in situ forming gels; Methylcellulose - analogs & derivatives; Methylcellulose - chemistry; Microscopy, Electron, Scanning; Molecular Weight; Nanoparticles - chemistry; Nanoparticles - ultrastructure; Particle Size; Polymer industry, paints, wood; Rheological behavior; Rheology; Silicon Dioxide - chemistry; Technology of polymers; Temperature; Viscosity
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2013.07.078

•Synthesis of plate-like β-TCP nanoparticles.•Preparation of a HPMC-based in-situ forming gel.•Adjusting the gelation point of the gel by β-TCP and HAp nanoparticles.•Elucidating the mechanism of nanofiller–polymer interactions. In this study, in situ forming gels are prepared using biphasic calcium phosphate (BCP) as filler and hydroxypropyl methylcellulose (HPMC) as a matrix exhibiting temperature-sensitive behavior. BCP was composed of β-tricalcium phosphate (β-TCP) with plate-like morphology and nano-sized hyadroxyapatite (HAp). Gel permeation chromatography (GPC) and rheological results showed that low molecular weight HPMC had lower gelation temperature. Effects of BCP content and HAp/β-TCP ratio on rheological behavior of the gels were investigated. According to the results, all samples showed a pseudoplastic behavior and their viscosity increased with increasing mineral phase, especially β-tricalcium phosphate. In order to investigate interaction mechanisms between the mineral phase and polymer and also the effects of ion release, particle size, hydrophobisity, and hydrophilisity, hydrophobic and hydrophilic silica with different particle sizes were also utilized. Results showed that factors affecting the hydrophobisity and hydrophilisity of solution may influence the rheological properties.