Standardization and performance evaluation of manual measurement method for paraoxonase activity

• Main Authors: Gökhan Çakırca, Osman Evliyaoğlu, Cemal Polat, Fatma Birgül Işık, Nuriye Mete
• Format: Article
• Language: English
• Published: Dicle University Medical School 2013-01-01
• Series: Dicle Medical Journal
• Subjects: Paraoxonase; standardization; internal quality control
• Online Access: http://www.diclemedj.org/upload/sayi/27/Dicle%20Med%20J-01603.pdf

Objectives: We hypothesised that using the traditionallaboratory methods for preparing the kit with chemicalsmay represent sufficient analytic performance with commercialkits, because of the fresh reagents and cost effective.We aimed to apply the paraoxonase (PON1) studyprocedure to the autoanalyser and evaluate the analyticperformance of the study.Methods: Thirty five healthy individuals were includedin the study. A total of 100 mL serum pool was createdafter centrifugation of venous blood samples. To assessthe intra-assay variations of PON1 enzyme activities 20samples and for inter-assay variations 30 samples wereprepared from the serum pool and PON1 enzyme activitieswere studied. As well as, 30 samples were studied toevaluate the correlation between the commercial kit andthe manual prepared kit from chemicals.Results: In this study, the mean, standard deviation (SD),percent coefficient of variation (% CV) values of PON1enzyme activities for intra-assay (72.70 U / L, 0.43, 0.59)and inter-assay (74.24 U / L, 3.00, 4.04) were determined.The correlation coefficient between the manual methodand the commercial kit were r = 0.92 and r2 = 0.84.Conclusion: The results of manual kit were showed goodanalytical performance with commercial kit. Therefore,the serum pool which was partially standardized in thisstudy was portionized for using as an internal quality controlserum for future studies in our laboratory. However,the use of standardized control sera, is considered to bemore reliable in routine laboratories.Key words: Paraoxonase, standardization, internal qualitycontrol