Ethylene oxide residue detector

1Ethylene oxide residue detectordetection method

1. Headspace Gas Chromatography (HS-GC)

Principle: Place the sample in a closed headspace bottle and equilibrate at a constant temperature for a period of time to allow ethylene oxide to evaporate from the matrix and reach gas-liquid equilibrium. Extract headspace gas and inject it into a gas chromatograph for analysis.

Advantages: Easy operation, high degree of automation, simple sample pretreatment, effective avoidance of matrix interference, high sensitivity, good reproducibility.

Scope of application: Medical devices, polymer materials, textiles, packaging materials, etc.

2. Solvent extraction gas chromatography method

Principle: Soak or extract the sample in organic solvents (such as water, acetone, dichloromethane, etc.), dissolve the residual ethylene oxide in the solvent, concentrate the extract, and inject it into a gas chromatograph for analysis.

Advantages: It can simultaneously detect ethylene oxide and 2-chloroethanol, suitable for certain dense materials that are difficult to release ethylene oxide.

Disadvantages: There are many pre-processing steps, which are time-consuming, and solvents may introduce interference.

3. Colorimetric method

Principle: Ethylene oxide reacts with a specific color reagent to produce colored compounds, which are quantified by measuring their absorbance using a spectrophotometer.

Advantages: Simple equipment requirements, low cost, and intuitive operation.

Disadvantages: Low sensitivity, poor selectivity, and susceptibility to interference from other substances.

IIEthylene oxide residue detectorExperimental steps (using headspace gas chromatography as an example)

Standard solution preparation: Accurately weigh an appropriate amount of ethylene oxide standard, prepare a reserve solution with anhydrous ethanol, and then dilute it step by step to different concentrations of standard working solution.

Sample pretreatment: Take about 1.0g of representative sample, cut it into pieces and place it in a headspace bottle. Add ultrapure water and seal immediately.

Headspace equilibrium conditions: Set parameters such as chromatographic column, injection port, detector, etc.

Standard curve drawing: Inject standard working solutions of different concentrations and draw standard curves.

Sample determination: Place the processed sample headspace bottle into an automatic sampler, inject the sample under the same conditions for analysis, and calculate the residual amount of ethylene oxide in the sample based on the standard curve.