在一連串的實驗過程中，我們已找到理想雙水相系統，選用的雙 水相系統為高分子-鹽類(PEG- K2HPO4)，PEG 分子量為 6000，銀奈 米粒子在此系統中會有不同尺寸上的分佈、和適當的 Kc 值（0.5~2），
並且利用高速離心即可把 PEG 和鹽類等雜質和銀奈米粒子所分離，
使達到純化的效果。我們還可以藉由添加尿素分子，可調控銀奈米粒 子在雙水相中的 Kc 值。最後，經最佳化實驗，我們選用 PEG 6000 (15%)，K2HPO4 (10%)的雙水相系統直接進行三次批式萃取，經 SEM 偵測後，觀測到原本不均勻的銀奈米粒子，會依不同尺寸而分離開 來。因此使用雙水相系統簡單進行幾次批次萃取後，就可以成功分離 不同大小尺寸的銀奈米粒子。
由於實驗室擁有 CPC 儀，在未來可把本研究中所找出的理想 PEG 6000 (15%)，K2HPO4 (10%)的雙水相系統，應用在 CPC 儀器中，藉 由控制動相流速、CPC 轉速以及調整動靜相組成，將有機會可以分離 更大量及分離更細微尺寸的銀奈米粒子。
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