明膠水凝膠作為一種具有良好生物相容性的天然聚合物，長期以來已被廣泛的應用於生物醫學領域。然而，由於往往缺乏合適的凝膠化溫度和機械特性等劣勢，極大地限制其在多樣且複雜體內環境下之臨床應用性。在這項研究中，我們提出基於霍夫麥斯特效應將明膠水凝膠浸泡於適當濃度硫酸鈉溶液，並由親水離子主導分子鏈間相互作用之變化，來對其多項性能進行全面性調整之策略。一系列經過不同鹽類濃度處理後的明膠水凝膠，微結構產生改變帶來孔隙數量及尺寸的總體下降、約32攝氏度至46攝氏度極廣的凝膠化溫度調整範圍、強至約40倍來到0.8345 MPa的應力增強、高至約7倍來到238.05% 的應變提升，以及一定程度的電導能力。因此，我們嘗試製備成微針貼片來進行應用性測試，其呈現出單根針體來至0.661牛頓的優秀針體穿刺(抗壓)強度。總的來說，在結合多種表徵並解釋背後機制下，這種方法提供了一種更加簡便高效的性質調控模式，並通用於A型及B型明膠水凝膠. 一方面，它能協助我們更好地預測明膠水凝膠使用在其他體內或體外鹽類環境中的可能變化。另一方面，多樣的性能改善及賦予能力也為如智能傳感器、電子皮膚和藥物輸送等領域，帶來了巨大的發展潛力。

As a natural polymer with good biocompatibility, gelatin hydrogel has been widely used in the field of biomedical science for a long time. However, the lack of suitable gelation temperature and mechanical properties often limit the clinical applicability in diverse and complex environments. Here, we proposed a strategy based on the Hofmeister effect that gelatin hydrogels were soaked in the appropriate concentration of sodium sulfate solution, and the change in molecular chain interactions mainly guided by kosmotropic ions resulted in a comprehensive adjustment of multiple properties. A series of gelatin hydrogels treated with different concentrations of the salt solution gave rise to microstructural changes, which brought a reduction in the number and size of pores, a wide range of gelation temperature from 32°C to 46°C, a stress enhancement of about 40 times stronger to 0.8345 MPa, a strain increase of about 7 times higher to 238.05%, and a certain degree of electrical conductivity to be utilized for versatile applications. In this regard, for example, we prepared microneedles and obtained a remarkable compression (punctuation) strength of 0.661 N/needle, which was 55 times greater than those of untreated ones. Overall, by integrating various characterizations and suggesting the corresponding mechanism behind the phenomenon, this method provides a simpler and more convenient performance control procedure. This allowed to easily modulate the properties of the hydrogel as per the intended purpose, revealing its vast potential applications such as smart sensors, electronic skin, and drug delivery.

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