矽量子點 (SiQD) 代表了一類新型先進材料，具有許多獨特且出色的特性，例如可調諧光致發光 (PL) 發射、光穩定性和可控表面官能團以及良好的生物相特性。 電容等，使其成為生物技術應用領域具有前瞻性和未來性的納米材料。 此外，Si作為地球上儲量豐富的元素，具有化學惰性、消耗成本低、生物友好、無毒等優點，在半導體工業中得到了廣泛的應用[1]。 此外，通過對SiQDs進行適當的表面功能化，可以通過氫鍵和靜電力實現Si表面的分子相互作用，從而實現生物分子的高靈敏度和選擇性檢測。 [2] 然而，目前的SiQD合成方法包括自上而下的方法（例如蝕刻和電化學方法）以及自下而上的方法（例如水熱和微波方法）。 通常這些傳統的合成方法耗時且需要昂貴的化學品、高溫和復雜的合成。 此外，這些傳統方法通常涉及有毒還原劑、複合穩定劑、強酸強鹼等。總體而言，目前仍缺乏一種簡便、快速的大規模生產方法來合成結構可控的表面功能化SiQDs。 具有高靈敏度和選擇性的生物分子檢測。
在這裡，我們報告了一種簡便的微等離子體工程，用於快速合成高質量的基於 SiQD 的納米凝膠 (SiQDNG)。 我們還探索了 SiQDNG 在傳感生物分子方面的潛力。 值得注意的是，等離子體合成的 SiQDNG 可以通過基於光致發光的傳感技術檢測葉酸和三磷酸腺苷 (ATP)。 葉酸最低傳感濃度達到92 nM，ATP最低傳感濃度達到35 nM。 我們的工作為生物分子傳感提供了優異的結果，並為基於 SiQD 的納米材料的合成和應用開闢了新的方向。

Silicon quantum dots (SiQDs) represent a new class of advanced materials with many unique and outstanding properties such as tunable photoluminescence (PL) emission, photostability and controllable surface functional groups and favorable biophasic properties. Capacitance, etc., making it a forward-looking and futuristic nanomaterial for biotechnology applications. In addition, as an earth-abundant element, Si has the advantages of chemical inertness, low consumption cost, biological friendliness, and non-toxicity, and has been widely used in the semiconductor industry [1]. In addition, through proper surface functionalization of SiQDs, molecular interactions on the Si surface can be achieved through hydrogen bonding and electrostatic forces, thereby achieving highly sensitive and selective detection of biomolecules. [2] However, current SiQD synthesis methods include top-down methods (such as etching and electrochemical methods) as well as bottom-up methods (such as hydrothermal and microwave methods). Usually these traditional syntheses are time-consuming and require expensive Chemicals, high temperature, and complex synthesis. In addition, these traditional methods usually involve toxic reducing agents, compound stabilizers, and strong acids and bases, etc. Overall, there is still a lack of a facile and rapid mass-production method to synthesize surface-functionalized SiQDs with controlled structures for the detection of biomolecules with high sensitivity and selectivity.
Here, we report a facile microplasma engineering for the rapid synthesis of high-quality SiQD-based nanogels (SiQDNG). We also explored the potential of SiQDNG for sensing biomolecules. Notably, the plasmonic-synthesized SiQDNG can detect folic acid and adenosine triphosphate (ATP) via a photoluminescence-based sensing technique. The lowest sensing concentration of folic acid reaches 92 nM, and the lowest sensing concentration of ATP reaches 35 nM. Our work provides excellent results for biomolecular sensing and opens new directions for the synthesis and application of SiQD-based nanomaterials.

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