蛋白質自組裝伴隨著一系列關於結構或功能上的特性，作為下一世代的生物材料引起眾多人的興趣，但如何良好的控制蛋白質自組裝是具有挑戰性的。因此，我們設計出一個簡易的方式，藉由奈米球模板和基板之間形成的奈米流體來引導蛋白質自組裝形成一個具高度規律性的蛋白質結構。在液滴蒸發的過程中，會因奈米球所產生的空間侷限性而使液滴在這其中產生許多不同的奈米流體，如圓形水環(circular water meniscus)、水橋(water bridge)或水膜(water film)。隨著溶劑進一步蒸發，一方面蛋白質會因溶劑蒸發而使其濃度越來越高；另一方面毛細作用力則會開始迫使蛋白質分子開始流動，使蛋白質自組裝成一個特定的結構，透過不同的奈米流體形狀以及乾燥的條件，就可以調控蛋白質自組裝後的形貌。在本篇研究中，我們充分地研究各種可以調控不同奈米流體的因素，如溶質的濃度、模板尺寸、乾燥溫度及溼度等，結果證實出不管在簡易的系統或者在複雜系統下，在這個實驗當中奈米流體扮演了一個很重要的角色，製作出環形、孔洞、同心環以及雙環的蛋白質結構。這些蛋白質結構具很大的可能性應用於未來生醫科學領域上。

Well-defined protein assemblies have been attracted interests as next-generation biomaterials with a remarkable range of structural and functional properties. However, it is challenging to organize proteins into well-controlled assemblies. We present a facile patterning method that uses evaporative sessile nanofluids formed between flat substrate and spherical templates to guide self-assembly of proteins into highly ordered and periodic arrays of nanostructures. During the evaporation process, the solution can be localized inside the spatial confinement on surfaces to form various nanofluids, such as circular water meniscus, water bridge or water film. As the solvent further evaporates, capillary forces enforce protein molecules to flow and concentrate within nanofluids, which guide protein molecules to assemble into well-defined structures. The morphology of the protein nanoscale assemblies are tunable, based on the selected shapes of nanofluids and drying conditions. In this research, we fully investigated the factors that enable to control the formation of nanofluids, such as solute concentration, template size, drying temperature, and humidity. Our results demonstrate nanofluid plays an important role in the experiments, regardless of simple or complicated systems, which produce protein assemblies with shapes of ring, cavity, concentric circle, or multiple ring arrangement. The protein nanostructures would be a good potential for applications of biomedical science.

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