How to detect ethylene oxide residue by original method?

1. Objective To prove the availability of medical devices sterilized by ethylene oxide through biological tests. \x0d\2。 Scope of application \x0d\ is suitable for the analysis and determination of ethylene oxide residues in products sterilized by ethylene oxide. \x0d\3。 Test basis \ x0d \ GB/t16886.7-20065438+0 Biological evaluation of medical devices Part VII \x0d\ISO 10993.7-2008 EO sterilization residue \x0d\4. Use the musical instrument \ x0d. SMIC Huili \x0d\ capillary column TM-624 0.5um*30m\x0d\ water bath pot /\x0d\ headspace sampling bottle 20mL\x0d\ silicone gasket PTFE membrane \x0d\ disposable syringe 1mL\x0d\ analytical balance/accuracy 0.6544. 4. Operation flow \x0d\4. 1 sample treatment: \x0d\ Unpack the dialysis package of the sample, select the part that is easy to disassemble and cut and difficult to analyze ethylene oxide, cut the sample into 5mm long pieces, take 1.0g sample, put it in a 20mL headspace sampling bottle, add 5mL pure water and seal it. \x0d\4.2 Sampling frequency \x0d\ Randomly take product samples from each sterilization batch. Generally speaking, the number of random samples in each sterilization batch is 5. \x0d\4.3 Preparation of ethylene oxide standard stock solution \x0d\ Take an externally dried 50 mL volumetric flask, add 20 ~ 30ml of water, add a cork, and weigh it to the accuracy of 0. 1mg. Inject about 0. 1mL of ethylene oxide with a syringe, shake it gently, cover it with a cork, and weigh it. The difference between the two weighing is the weight of ethylene oxide contained in the solution. Calculate the concentration of the reserve solution and store it below 4℃ for later use. \x0d\4.4 Preparation of standard working fluid \x0d\ Take 1mL stock solution and prepare it into 1× 10-3g/L, 2× 10-3g/L and 4×/kloc-0 respectively. Sealed for later use. Take 5mL each and treat it according to the method of 4. 1. \x0d\5。 Operation of gas chromatograph \x0d\5. 1 Turn on the power supply of the nitrogen, hydrogen and air integrated machine, open the nitrogen purge valve on the right side for at least 30 minutes, close the nitrogen purge valve, and restore the pressure of nitrogen and hydrogen to 0.4MPa. \ x0d \ 5.2 Open the gas purification valve. \x0d\5.3 Turn on the power supply and workstation software of the gas chromatograph, press the ignition button after the air pressure and flow rate are balanced, and observe whether the baseline changes and FID detection port generate steam. \x0d\5.4 parameter setting \x0d\ parameter capillary column \x0d\ temperature evaporator \x0d\ temperature FID detector \x0d\ temperature analysis time sample \x0d\ setting value 50℃140℃/2h0. \x0d\5.6 Quickly extract 1mL upper layer gas from the balanced standards and samples with a glass syringe, insert it into the injection port of the capillary column, inject the sample, and then click the "OK" button on the operation panel (pay attention to the injection speed during injection to prevent gas from escaping and retreating). \x0d\5.7 Select the standard spectrum and correct the standard curve. Substitute the sample atlas into the standard curve (x: ethylene oxide concentration, g/l; Y: peak height or peak area), and calculate the residual amount of ethylene oxide in the sample according to the dilution ratio of the sample to pure water 1: 5. \x0d\5.8 Calculation of results \ x0d \ WEO =[ Leaching solution volume ×(EO peak area-125.1)194.34]/leaching sample weight \x0d\6. According to the determination result of \ x0d \. \x0d\7。 Precautions \x0d\7. 1 When the FID detector in the gas chromatograph is closed, the hydrogen channel should be closed first, and then the air channel should be closed. \x0d\7.2 Before the gas chromatograph is shut down, the temperature of the sample inlet, column temperature box and FID detector should be reduced to room temperature or below 50℃ before it can be shut down. \x0d\7.3 All the sample preparation work carried out by analysts, including the use of chemical reagents, should be carried out in a fume hood and wear protective clothing. Please read the material safety instructions before using chemicals. \x0d\7.4 An analysis shall be operated by the same person as far as possible, using the same 1mL glass syringe and keeping the same temperature with the sample in advance. \x0d\7.5 Pay attention to the change of ethylene oxide residence time every time to prevent the injection gasification pad from leaking. \x0d\7.6 Each sample (including standard samples) should be analyzed for three times in the shortest possible time, and the difference between the two results in the three analyses must be less than or equal to 5%, otherwise the sample should be reanalyzed.