【讨论】个别网友求助帖探讨（有关气相色谱残留溶剂，christe和lqqer请进）

1 christe求助的翻译帖

请这个网友今后请教时不要怕出洋相，把自己翻译好的东西先拿出来让大家看一下。只有这样，我们才知道你的错在哪里，可以对症下药。通过对比，你的提高会更快。全盘接受没有经过自己大脑思考，我不提倡。

Limit of diethylene glycol and related compounds—

Resolution solution— Dissolve accurately weighed quantities of diethylene glycol and USP Glycerin RS in water, and dilute quantitatively, and stepwise if necessary, with water to obtain a solution having a known concentration of about 0.5 mg of each per mL.
Standard solution— Dissolve an accurately weighed quantity of diethylene glycol in water, and dilute quantitatively, and stepwise if necessary, with water to obtain a solution having a known concentration of about 0.05 mg per mL.
Test solution— Transfer 5 g of Glycerin, accurately weighed, to a 100-mL volumetric flask, dissolve in and dilute with water to volume, and mix.

二甘醇及有关物质限度检查

分离度测试溶液：取二甘醇和美国药典甘油参比标准品适量,精密称定,用水溶解,定量稀释,必要时用水逐级稀释,制成每ml约0.5mg的溶液.

标准溶液-取二甘醇适量,精密称定,用水溶解,定量稀释,必要时逐级稀释,制成每ml约0.05mg的溶液.

待测溶液-取甘油5g,精密称定,置100ml容量瓶中,用水溶解并稀释至刻度.摇匀.(happyjyl译）

Chromatographic system (see Chromatography 621 )—The gas chromatograph is equipped with a flame-ionization detector, a 0.53-mm × 30-m fused-silica analytical column coated with 3.0-µm G43 stationary phase, and an inlet liner having an inverted cup or spiral structure. The chromatograph is programmed as follows. Initially, the column temperature is equilibrated at 100 until the time of injection, is increased at a rate of 7.5 per minute to 220 , and is maintained at 220 for 4 minutes. The injection port temperature is maintained at 220 , and the detector temperature is maintained at 250 . The carrier gas is helium. The split flow ratio is about 10:1, and the linear flow is maintained at about 38 cm per second. Chromatograph the Resolution solution, and record the peak responses as directed for Procedure: the resolution, R, between diethylene glycol and glycerin is not less than 7.0. Chromatograph the Standard solution, and record the peak responses as directed for Procedure: the relative standard deviation for replicate injections is not more than 15%.

色谱系统（见色谱法〈621〉）：配有氢火焰离子化检测器的气相色谱仪，色谱柱为 G43（0.53mm× 30m× 3μm）弹性石英毛细管柱，进样口衬管类型为内卷杯状，程序升温：100℃→7.5℃／min→220℃（4min）。进样口温度220度，检测器温度250度。载气为氦气。分流比为10：1，线速度：38cm／s。分离度测试溶液进样后，色谱图中二甘醇和甘油两峰的分离度不得低于7.0。标准溶液进样后，记录色谱峰面积，其相对标准差不得过15％（lqqer译，mhq111111修改）

Procedure— Separately inject equal volumes (about 0.5 µL) of the Standard solution and the Test solution into the chromatograph, record the chromatograms, and measure the responses for all the peaks. Calculate the percentage of diethylene glycol in the portion of Glycerin taken by the formula:
100(CS / CU)(rU / rS),
in which CS is the concentration, in mg per mL, of diethylene glycol in the Standard solution; CU is the concentration, in mg per mL, of Glycerin in the Test solution; and rU and rS are the peak responses for diethylene glycol obtained from the Test solution and the Standard solution, respectively: not more than 0.1% is found. Calculate the percentage of each other impurity, excluding any solvent peaks, in the portion of Glycerin taken by the formula:
100(ri / rs),
in which ri is the peak response of each individual impurity obtained from the Test solution; and rs is the sum of the responses of all the peaks obtained from the Test solution: not more than 0.1% of any individual impurity, excluding diethylene glycol, is found; and not more than 1.0% of total impurities, including diethylene glycol, is found.

2 lqqer的求助帖

Limit of acetone and methanol—

Standard preparation— Transfer 5.0 mL of acetone to a 1000-mL volumetric flask, dilute with water to volume, and mix (Solution A). Transfer 5.0 mL of methanol to a 1000-mL volumetric flask, dilute with water to volume, and mix (Solution B). Transfer 50.0 mL of Solution A and 5.0 mL of Solution B to a 500-mL volumetric flask, dilute with water to volume, and mix to obtain a solution having concentrations of acetone and methanol of 0.050% and 0.005% (v/v), respectively.
Test preparation— Transfer 5.0 g of Cefoxitin Sodium to a 50-mL volumetric flask, dissolve in and dilute with water to volume, and mix. Transfer 3.0 mL of the resulting solution to a 15-mL centrifuge tube, cool in an ice-water bath for 2 minutes, and add 3.0 mL of 0.24 N hydrochloric acid while swirling vigorously. Centrifuge to obtain a clear solution (Test preparation).
Chromatographic system (see Chromatography 621)—The gas chromatograph is equipped with a flame-ionization detector, and contains a 1.8-m × 6.3-mm glass column containing support S2, and a pre-column packed with 60- to 80-mesh silane-treated glass beads. The injection port is maintained at 100, the columns are maintained at 110, the detector is maintained at 200, and nitrogen is used as the carrier gas at a flow rate of about 50 mL per minute. Chromatograph the Standard preparation, and record the peak responses as directed under Procedure: the column efficiency determined from the acetone and methanol peaks is not less than 160 and 200 theoretical plates, respectively; the tailing factors for the acetone and methanol peaks are not more than 1.3 and 2.3, respectively; and the relative standard deviation for replicate injections is not more than 5%.
Procedure— [NOTE—Use peak areas where peak responses are indicated.] Separately inject equal volumes (about 2 µL) of the Standard preparation and the Test preparation into the chromatograph, record the chromatograms, and measure the acetone and methanol peak responses. Calculate the percentages of acetone and methanol in the Cefoxitin Sodium taken by the same formula:
15.8P(rU / rS),
in which P is the percentage (v/v) of acetone or methanol in the Standard preparation; and rU and rS are the acetone or methanol peak responses of the Test preparation and the Standard preparation, respectively: not more than 0.7% of acetone and 0.1% of methanol are found.

斑竹考考大家：

1 你知道USP的气相色谱柱共有几种？上面的G43和S2分别涂布的是什么固定液？我们国内对应的色谱柱叫什么名字？

2 假定我要分离3个组分，沸点、极性相差比较大，在没做实验之前，脑子里希望得到的色谱峰（理想状态）是怎样的？

请教lqqer:
a 1.8-m × 6.3-mm glass column containing support S2, and a pre-column packed with 60- to 80-mesh silane-treated glass beads.
这个柱子前面加有预柱，我没用过，是属于填充柱吗？
这个问题已经解决，算是自问自答：是属于填充柱，填充柱包括玻璃柱和不锈钢柱。我用的柱子都是毛细管柱。

to lqqer:这句话你没有翻译出来
and record the peak responses as directed for Procedure:

我觉得可以直译：
as directed for procedure:按测定法项下规定的条件记录色谱峰响应。
（有点不通顺，有更好的翻译吗？）

G43 相当与DB-1301(6%-腈丙基苯基)甲基聚硅氧烷,属于中极性.
如我现在检测的二甘醇和甘油,二甘醇会先出峰.甘油的极性大于二甘醇,所以晚出峰

没有做过实验,这些问题我都不会回答

as directed for procedure: 如操作步骤中所述

不好意思，今天刚刚看到
我用的时候，以现有条件，没有办法完全按照标准实现。
在这个实验里，我们用得是玻璃填充柱。

多谢参与回答．你的这个试验其实不属于有机残留溶剂，而是属于有关物质检查．一般都用液相色谱来做．在气相里，它的操作步骤与残留溶剂类似．
DB-1301和DB-624都是对的，都是指6%-氰丙基苯基-９４％甲基聚硅氧烷柱．