根據研究，含有重複四級銨陽離子的聚（甲基丙烯酸三甲基氨基）乙酯（pTMAEMA）聚合物在醫院感染中具有有效的抗微生物活性。然而，pTMAEMA水凝膠的三維結構在結果中所顯示很低的最大壓縮應力，表示其機械性質是弱的。聚合物鏈段之間的低摩擦力和聚合物鍊長度的不均勻分佈導致水凝膠有柔軟和易脆的特性。這些特性限制了pTMAEMA水凝膠在生物材料中的潛在應用。因此，我們透過天然的多原子價植酸（PA）將可逆的物理性交聯劑加入pTMAEMA網狀結構。 PA的機械性質和生物性的增強使其廣泛地運用於生物醫學材料。在pTMAEMA水凝膠的四級銨基團和PA的陰離子基團之間形成的離子鍵（pTMAEMA-PA水凝膠）改善了水凝膠的韌性和耐久性（壓縮斷裂應力高於1百萬帕，在4次加載 - 卸載循環後的遲滯現象穩定性）。此外，在低至高偏移下的壓縮模數的變化以及在增加的鹽濃度下水凝膠的體積比的變化表示PA的離子橋接。 此外，由於可逆的物理交聯劑，pTMAEMA-PA如滯後應力-應變曲線所示，顯示出類似彈性體的特性。有趣的是，pTMAEMA與六偏磷酸鈉（PP6-）對接顯示出對細菌高度抗沾黏性，而pTMAEMA-PA水凝膠由於PA的強螯合能力而獲得殺菌效果。這一發現可能會擴大pTMAEMA水凝膠在未來作為多功能抗菌材料的應用範圍。;Poly((trimethylamino)ethyl methacrylate chloride) (pTMAEMA) brushes, containing repeated quaternary ammonium cations, has been proposed with efficient antimicrobial activity in nosocomial infection. However, 3-dimentional structure as pTMAEMA hydrogels shows weak mechanical properties as demonstrated in the result of low maximum compressive stress. The low friction between polymer chains and the heterogeneous distribution of the polymer chain length lead to the soft and brittle characteristics of the polyelectrolyte hydrogels. These characteristics limit the potential applications of pTMAEMA as biomaterials. Therefore, we introduce reversible physical crosslinkers to pTMAEMA network via docking natural multivalent phytic acid (PA). PA has been widely used for the mechanical enhancement of biomedical materials. Ionic bonds formed between quaternary ammonium groups of pTMAEMA hydrogels and anion groups of PA (pTMAEMA-PA hydrogels) improve their toughness and durability (compressive fracture stress above 1 MPa, hysteresis loop stability after 4 loading-unloading cycles). Furthermore, the change in the compressive modulus at low to high offset, and the change in the volume ratio of the hydrogels under the increasing saline concentration suggest the ion-bridging of PA. In addition, owing to the reversible physical crosslinkers, pTMAEMA-PA also displayed elastomer-like characteristic as shown in the hysteresis stress-strain curve. Interestingly, pTMAEMA docking with sodium hexametaphosphate (PP6-) shows high resistance to bacterial fouling, while pTMAEMA-PA hydrogels acquire bactericidal effect due to the strong chelating capacity of PA. This finding may broaden the application of pTMAEMA hydrogels as a versatile antibacterial material in the future.
