非固醇類抗炎劑之光分解。第二報。以液相層析－－質譜法連線測定卡普洛芬光分解產物   全文下載

Photolysis of NSAIDs. II. Online LC-MS Determination of Photodegradants from Carprofen

將卡普洛芬溶於10%乙醇水溶液中而成0.1毫克／毫升之濃度，然後以太陽光連續照射24小時，總共形成四種光解產物。先以液相層析法分離，再以連線之質譜儀分別測定其偽分子離子。液相層析法使用Inertsil 5 ODS-80A管柱（150毫米×2.1毫米內徑），開始時移動相組成為乙?：醋酸銨（20毫莫耳溶於去離子淨水） = 43:57（v／v）； 14分鐘後，乙?：醋酸銨變為54:46 （v／v）。紫外光監測器波長為260nm。以液相層析質譜法測定分子量部份，其參數乃採用API介面之電灑法並選擇負電荷模式。光解產物之化學構造以偽分子離子峰之分子量解析之。其中兩種光解產物之生成乃先經一去氯基反應。據觀察，去氯基反應與去殺羧反應形成競爭。以上結果與本研究室先前發表卡普洛芬之光解動力學係一次反應之結果相符合。

Carprofen in a 10% aqueous ethanol solution at a concentration of 0.10 mg/mL was subjected to photo-irradiation under sunlight for 24 hr. Four photodegradants were separated and subsequently followed an online determination of their quasi molecular ions using an LC-MS method. The HPLC consisted an Inertsil 5 ODS-80A (2.1 mm i.d. × 150 mm) column, and the mobile phase was initially CH3CN: NH4OAc (20 mM in D.I. H2O) = 43: 57 (v/v). After 14 min, CH3CN: NH4OAc (20 mM in D.I. H2O) was changed to 54: 46 (v/v). The UV detector was set at 260 nm. The parameters of LC-MS for mass determination were optimized with an API electron spray interface with negative mode of polarity (ESI–). The chemical structures of the degradants were elucidated based on the m/z of the quasi molecular ions. Two degradants were found to proceed via an initial dechlorination with C-Cl cleavage. Dechlorination was observed to be competing with decarboxylation, i.e. either reaction is in accord with our previously reported result with a first-order photodecomposition kinetics of carprofen. 將卡普洛芬溶於10%乙醇水溶液中而成0.1毫克／毫升之濃度，然後以太陽光連續照射24小時，總共形成四種光解產物。先以液相層析法分離，再以連線之質譜儀分別測定其偽分子離子。液相層析法使用Inertsil 5 ODS-80A管柱（150毫米×2.1毫米內徑），開始時移動相組成為乙腈：醋酸銨（20毫莫耳溶於去離子淨水） = 43:57（v／v）； 14分鐘後，乙腈：醋酸銨變為54:46 （v／v）。紫外光監測器波長為260nm。以液相層析質譜法測定分子量部份，其參數乃採用API介面之電灑法並選擇負電荷模式。光解產物之化學構造以偽分子離子峰之分子量解析之。其中兩種光解產物之生成乃先經一去氯基反應。據觀察，去氯基反應與去殺羧反應形成競爭。以上結果與本研究室先前發表卡普洛芬之光解動力學係一次反應之結果相符合。