利用Ethyl Acetate去除因高血脂引起生化檢驗監測之干擾

Use of Ethyl Acetate Extraction in Eliminating Lipemic Interference in Clinical Chemistry Analysis: Experience on Hitachi 7170 Analyzer

脂血檢體主要是由乳糜微粒大量存在於血液檢體中所造成的，對於臨床實驗室在檢體測定上造成諸多困擾，因為在臨床生化的測定主要是利用光比色法或離子選擇電極，所以對臨床生化檢驗項目的干擾更為明顯。在臨床上常用於去除脂血的方式有化學沉澱法、酵素法、清潔劑法、層析法、超高速離心法及溶劑萃取法等方法，而在這些方法中又以超高速離心法最被認定（Joseph，1987）。在本實驗之前也有其它有機溶劑被應用於去除脂血檢體的干擾，但都有毒性過大或結果不佳的情形出現。本實驗室以ethyl acetate處理脂血檢體後，於生化分析儀測定結果發現在一些項目的測定值與超高速離心法所處理的結果值較接近，表示以ethyl acetate處理後所得結果為可信賴的結果，同時對照原先未經處理的脂血檢體，可發現有統計上差異存在。所以本實驗的初步結果對於臨床生化分析儀的一些測定項目，確實可以去除脂血對檢體測定上的干擾，因此可廣泛應用於中小型實驗室，以解決脂血干擾的問題。

Lipid particles in lipemic serum or plasma specimen causes analytical errors in spectrophotometric and ion-selective electrode analysis. Methods for eliminating the interference in clinical laboratory include precipitation, enzymatic digestion, extraction, ultrafiltration and so forth. Ultracentrifugation has been considered as effective means for clarifying lipemic specimens; however, the method is not readily accessible and not cost-effective. Attempts to eliminate the interference by solvent extraction have encountered problem of toxicity or protein denaturation. Our aim was to determine the effect of the interference of lipemia and use organic Solvent (ethyl acetate, EA) extraction to remove the interference on chemistry test in clinical laboratory. The blood samples were centrifuged at 1500g for 10min and the cells were discarded; the serum or plasma was stored at -20°C until analysis. In this study, we investigated the difference between added EA and without EA in the lipemic specimens (triglyceride concentration above 1000mg/dL). All samples were divided into three groups, and the control group was analyzed ultracentrifugation for 8 min at 90,000g, the second group added EA and the third group without EA treatment before analyte measurement. Our preliminary data indicate that the turbidity of lipemic specimen treatment of ethyl acetate could efficiently remove lipid interference in partial analytic tests.