半夏
第2楼2008/04/24
找到了Draft Method 1614
《Brominated diphenyl ethers in water, soil, sediment, and tissue by HRGC/HRMS》中的PBDEs标准品保存方法
7.7 Standard solutions—Prepare from materials of known purity and composition or purchase as
solutions or mixtures with certification to their purity, concentration, and authenticity. If the chemical purity is 98 % or greater, the weight may be used without correction to calculate the concentration of the standard. Observe the safety precautions in Section 5 and the recommendation in Section 5.1.2.
7.7.1 For preparation of stock solutions from neat materials, dissolve an appropriate amount of assayed reference material in solvent. For example, weigh 1 to 2 mg of BDE 99 to three significant figures in a 10-mL ground-glass-stoppered volumetric flask and fill to the mark with nonane. After the compound is completely dissolved, transfer the solution to a clean 15-mL vial with fluoropolymer-lined cap.
7.7.2 When not being used, store standard solutions in the dark at room temperature in screwcapped vials with fluoropolymer-lined caps. Place a mark on the vial at the level of the solution so that solvent loss by evaporation can be detected. Replace the solution if solvent loss has occurred.
不知道大家用得是不是这个保存方法
lulutaotao
第4楼2008/05/01
我们也出过这种情况,我想应该是进样隔垫流失造成的硅氧烷峰。而且我们的标样似乎已经分解了,还出了许多杂峰。我们是把配好的标准溶液放在进样小瓶中,用完后在冰箱里冷冻保存,但是效果似乎不是特别好,溶剂(甲苯)有挥发掉的迹象。