Determination of Ethylene Chlorohydrin in Intraocular Lenses by GC-MS

Ethylene chlorohydrin (ECH) was extracted from the sample with acetone. The extract containing the analyte was then analyzed by GC-MS in hyphenation under the following conditions. GC analytical conditions: ① ZB-624 chromatographic column was used, with a temperature of 180 ℃ at the inlet of sample and effluent splitting ratio of 1 to 1; ② high purity helium was used as carrier gas, with a flow-rate of 1.5 mL·min-1; ③ program of temperature elevation: keeping for 1 min at the initial temperature of 50 ℃, raising to 100 ℃ at a rate of 5 ℃·min-1 and keeping for 1 min at 100 ℃. MS analytical conditions: ① temperature of ionic source: 230 ℃; ② temperature at the interface of GC and MS: 250 ℃; ③ electrical energy: 70 eV. Retention time and full-scanning in the mass range of m/z 35 to 500 were used for qualitative analysis; and external standard method under SIM mode with selected ion of m/z 43 was used for quantification of ECH. The number of theoratical plates of this method was found higher than 56 753. Linearity range found for ECH was between 1.44 to 22.96 mg·L-1 and the detection limit (3S/N) was found to be 0.41 mg·L-1. Recovery was tested by standard addition method, giving value of recovery 99.1%. Value of RSD′s (n=5) was less than 5%.