| 查看: 2069 | 回复: 3 | ||||
[求助]
气相色谱检测方法问题，请教大家！！
|
|
这个方法是做顶空的吗？ 各位老师，帮帮忙，小弟是新手。 这是整个气相方法： TESTS pH (2.2.3): 6.5 to 7.5. Dissolve 0.20 g in carbon dioxide-free water R and dilute to 10 mL with the same solvent. Impurity C. Gas chromatography (2.2.28). Silylation solution. To 2 mL of N,O-bis(trimethylsilyl)tri- fluoroacetamide R add 0.04 mL of chlorotrimethylsilane R and mix. Test solution.Dissolve50.0mgofthesubstancetobeexamined in 3 mL of water R and add 0.5 mL of hydrochloric acid R. Extract with 2 quantities, each of 5 mL, of methylenechlorideR. Evaporate the combined methylene chloride extracts to dryness in a vial with a screw cap and add 0.5 mL of the silylation solution.Sealthevialandheatat70±5°Cfor20min. Reference solution (a).Dissolve5.0mgof sodium phenylbutyrate impurity C CRS in methylenechlorideR and dilute to 10.0 mL with the same solvent. Reference solution (b). Dilute 1.0 mL of reference solution (a) to 10.0 mL with methylenechlorideR.Place1.0mLofthis solution in a vial with a screw cap, evaporate to dryness and add 0.5 mL of the silylation solution. Seal the vial and heat at 70±5°Cfor20min. Reference solution (c). Dissolve 10 mg of the substance to be examined in 25 mL of water R. To 3 mL of this solution add 0.1 mL of hydrochloric acid R. Extract with 2 quantities, each of 5 mL, of methylene chloride R. Combine the methylene chloride extracts in a vial with a screw cap and add 2 mL of reference solution (a). Evaporate to dryness and add 0.5 mL of the silylation solution. Seal the vial and heat at 70 ± 5 °C for 20 min. Column: — material :fusedsilica; — size: l =25m,?=0.25mm; — stationary phase: poly(dimethyl)(diphenyl)siloxane R (film thickness 1.0 μm). Carrier gas : helium for chromatography R. Flow rate:0.9mL/min. Split ratio: 1:100. Temperature: Time(min) Temperature(°C) Column 0-5 50 5 - 27 50 → 270 27 – 32 270 Injection port 270 Detector 270 Detection:flameionisation. Injection:1 μL. Relative retention with reference to phenylbutyrate (retention time = about 20 min) : impurity C = about 0.98. System suitability: reference solution (c) : — resolution: minimum 3.0 between the peaks due to impurity C and phenylbutyrate. Limit : — impurity C:notmorethantheareaofthecorresponding peak in the chromatogram obtained with reference solution (b) (0.1 per cent). Related substances. Liquid chromatography (2.2.29). 这个方法是不是顶空方法，如果是的话，里面怎么没有顶空条件？难道是硅烷化反应的条件就包含了顶空条件（Seal the vial and heat at 70 ± 5 °C for 20 min.）还是说顶空条件要自己摸索？ |
回复此楼» 收录本帖的淘帖专辑推荐
 气相色谱资料汇编 | 液相色谱 气相色谱 |
» 猜你喜欢
时间戳变了，能看出什么问题？
已经有20人回复
-
重要消息，中午系统在维护
已经有12人回复
-
哪位老哥知道今年的国自然具体哪一天放榜？
已经有20人回复
-
言之凿凿，8月21号(明天)放榜
已经有14人回复
-
只有每年这种时候来逛逛小木虫
已经有21人回复
-
今天基金会出结果吗？20260819
已经有15人回复
-
filecode，4个jtjc了
已经有13人回复
-
为什么余额宝的年化利率越来越低？主要原因有哪些？
已经有5人回复
-
今天放榜没戏了吧
已经有5人回复
-
今天放榜吗？
已经有15人回复
» 本主题相关价值贴推荐，对您同样有帮助:
- 求助 沸点为218℃的物质用气相色谱可以检测吗？气相对测样沸点有没有要求？？？
已经有11人回复
- 气相色谱操作 检测器问题，谢谢大家！！
已经有3人回复
- 请教高手：气相色谱问题
已经有25人回复
- 气相色谱检测相关小问题，请教大家一下！！
已经有3人回复
- 【求助】气相色谱调大分流比时候，峰分叉，请教大家原因！
已经有7人回复
- 【求助】气相色谱 检测问题？
已经有4人回复
- 【求助】急求双酚A气相色谱检测前衍生化问题
已经有9人回复
- 【求助】请教：气相色谱 内标物含量问题？
已经有6人回复
- 【求助】请教：气相 检测气体问题？
已经有5人回复
2楼2012-02-09 09:19:12
3楼2012-02-09 13:27:31
apm19861204
金虫 (小有名气)
- 应助: 9 (幼儿园)
- 金币: 1236.7
- 散金: 34
- 帖子: 107
- 在线: 207小时
- 虫号: 459611
- 注册: 2007-11-14
- 专业: 色谱分析
4楼2012-02-09 17:01:38
