在已知醇類溶劑和水混和，並加入丙酮作為光引發劑，在紫外光254nm的照射下，可以產生對雙硫鍵有還原作用的自由基，藉由調控曝光於紫外光下的時間，可以控制對蛋白質雙硫鍵還原的程度，並且可運用於解析蛋白質雙硫鍵結構。我們將此反應系統與液相層析系統做結合，讓此反應系統可以適用於多個蛋白質或胜肽的複雜樣品，以及利用液相層析系統來分離還原程度不同的蛋白質，讓其運用範圍更加廣泛。
為了適用於液相層析系統，我們選用了水與甲醇作為動相，並且以不同比例的水與甲醇混和，分別以不同流速做比較，以確保在不同梯度下的光反應效率是足夠的。最後再搭配紫外光反應槽，確保能準確微調蛋白質還原的程度。
　　裝設光反應槽的位置有兩處，一個是在管柱後，即是本系統可以一次處理多個樣品，讓蛋白質個別被液相層析管柱分離後，再進行還原，藉由比較（總離子層析圖同一時間）有無照射紫外光的圖譜，可以比較蛋白質樣品還原前後的質量色譜圖差異；另一個是將光反應槽裝設於管柱前，在層析分離之前，蛋白質樣品之雙硫鍵已經被不同程度的還原了，之後可以藉由逆相層析管柱將還原程度不同的蛋白質做分離，並分別對不同還原程度的蛋白質做二次質譜鑑定其結構，可以得到其雙硫鍵結構的資訊。
　　此方法我們先選擇胰島素作為目標蛋白，經過光反應後由逆相層析管柱將胰島素分成原胰島素，胰島素A序列以及胰島素B序列，之後再分別對胰島素A序列以及原胰島素做低能量碰撞二次質譜，可以得到胰島素的雙硫鍵結構資訊。之後我們同時使用胰島素以及α-乳清蛋白，證明此方法可以同時分析一種以上的蛋白質，並且仍有不錯的分析能力。

Depending on the ACS paper, “Acetone/Isopropanol Photoinitiating System Enables Tunable Disulfide Reduction and Disulfide Mapping via Tandem Mass Spectrometry’’. Alcohol with 1% acetone under UV 254 nm light can create radicals which can reduce protein disulfide bonds. By adjusting UV exposure time, the system can control the disulfide bonds reducing level, furthermore characterizing disulfide linkages. In this paper, We combined this UV reaction system with liquid chromatography to make it suitable for complex proteins or peptide samples. Or it can separate different reducing level proteins to make disulfide mapping easier.
We chose water and methanol as the LC mobile phase. By changing the ratio of water to methanol and controlling the flow rate, we can make sure the reaction efficiency is enough. And we used the UV flowcell to control the parameter accurately.
There were two sites to install UV flowcell. One site was after C4 column, which could reduce proteins or peptides disulfide bonds after separation. This meant we could run a complex sample on the UV flowcell system. The other site was before C4 column, which could separate different disulfide bond reducing level proteins after the UV reaction. By CID MS2 of those different reducing level proteins, we could gain the protein disulfide bond information.
We chose insulin as our model protein. After UV reaction, the C4 column separated insulin, insulin A chain and insulin B chain. And then we could get insulin disulfide bond information via CID-MS2 of insulin and insulin A chain. We also tried to inject two proteins one time to prove that the UV reaction efficiency was still good under multiple protein samples.

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