原文由 owenhys 发表:
有用液质或液相做奶粉中叶酸含量测定的吗?怎么前处理的? 我参照药典,用水提取样品,不能得到澄清溶液,混悬液,该怎么解决才能澄清上机呢?
Add 1 mL of 10% Ammonium hydroxide to standard or sample solution.
Did you try the the method on USP 32, Page 2444.?
Mobile phase: 2.0 g of KH2PO4 into 650 mL of H2O, Add 15 mL of 0.5 M Tetrabutylammonium hydroxide in methanol, 7.0 mL of 3N H3PO4, and 270 mL of Methanol. Adjust to pH of 5.0 with 3N of H3PO4 or 6N Nh4OH.
得到澄清溶液: for standard preparation and sample preparation:
Add 1 mL of 10% Ammonium hydroxide and dilute to volume with the mobile phase. USP recommend internal standard method calculation, however it's fine to use external standard calculation.
Hope it helps.