Institute of Interfacial Process Engineering and Plasma Technology IGVP, University of Stuttgart ; Nobelstr. 12, 70569 Stuttgart, Germany.
Max Planck Institute for Developmental Biology ; Max-Planck-Ring 5, 72076 Tübingen, Germany.
Biomacromolecules. 2018 Jan 8;19(1):42-52. doi: 10.1021/acs.biomac.7b01221. Epub 2017 Dec 21.
Cross-linkable gelatin methacryloyl (GM) is widely used for the generation of artificial extracellular matrix (ECM) in tissue engineering. However, the quantification of modified groups in GM is still an unsolved issue, although this is the key factor for tailoring the physicochemical material properties. In this contribution, H-C-HSQC NMR spectra are used to gain detailed structural information on GMs and of 2-fold modified gelatin containing methacryloyl and acetyl groups (GMAs). Distinctive identification of methacrylate, methacrylamide, and acetyl groups present in GMs and GMAs revealed an overlap of methacrylamide and modified hydroxyproline signals in the H NMR spectrum. Considering this, we suggest a method to quantify methacrylate and methacrylamide groups in GMs precisely based on simple H NMR spectroscopy with an internal standard. Quantification of acetylation in GMAs is also possible, yet, 2D NMR spectra are necessary. The described methods allow direct quantification of modified groups in gelatin derivatives, making them superior to other, indirect methods known so far.
可交联的明胶甲基丙烯酰基（GM）广泛用于组织工程中人工细胞外基质（ECM）的生成。然而，尽管这是调整物理化学材料特性的关键因素，但 GM 中修饰基团的定量仍然是一个未解决的问题。在本研究中，我们使用 H-C-HSQC NMR 谱来获得 GM 和含有甲基丙烯酰基和乙酰基的 2 倍修饰明胶（GMAs）的详细结构信息。在 GM 和 GMAs 中存在的甲基丙烯酸盐、甲基丙烯酰胺和乙酰基的独特鉴定揭示了在 H NMR 谱中甲基丙烯酰胺和修饰的羟脯氨酸信号的重叠。考虑到这一点，我们建议了一种基于带有内标简单 H NMR 光谱精确定量 GM 中甲基丙烯酰基和甲基丙烯酰胺基团的方法。GMAs 中乙酰化的定量也是可能的，但需要二维 NMR 谱。所描述的方法允许直接定量明胶衍生物中的修饰基团，使其优于迄今为止已知的其他间接方法。
