較常用於古柯鹼定量之方法,為高效液相層析法和氣相層析法兩種,比較此兩儀器對古柯鹼標準品之最低檢出量分別為100ng及4ng,故採用氣相層析儀分析之。又前處理時pH值及有機溶媒的選擇也影響著回收結果,添加標準品溶液於樣品中,使其最終濃度為0.2, 0.5及1.0ppm,各濃度分別作三重覆,其平均回收率為82.8%, 55.2%及88.1%,總平均回收率為85.4%,由結果顯示本檢驗方法可用於飲料中古柯鹼含量之檢驗,而其最低檢出量為0.05ppm。
A GC method was firstly compared with HPLC for cocaine content in a soft drink. The result indicated that the GC possessed higher sensitivity for cocaine hydrochloride. Its detecting limit was 4ng compared to 100ng by HPLC. Therefore the GC method was used in the further study. The cocaine solution were added to a soft drink at the final concentrations of 0.2, 0.5 and 1. ppm, the cocaine recoveries in the average of triplicate were 82.8, 85.2 and 88.1% respectively. The total average recovery was 85.0%. the cocaine recovery was especially influenced by the conditions of pH and solvent during extration. The present GC method for cocaine showed a detection limit at 0.05ppm.