Vitamin B12/Folate 검사 시 빛의 영향에 대한 고찰

Study of the Impact of Light Through the Vitamin B12/Folate Inspection

Purpose : Vitamin B12 and Folate are for anemia work-up which is well known for its sensitivity of light; the screening manual also specifies to be careful with light conditions. According to this, our laboratory minimized the exposure of light when inspecting the Vitamin B12 and Folate, but the exposure cannot be wholly blocked due to other various factors such as when conducting specimen segregation. Thus, this inspection is to identify to what extent light can influence and whether the exclusion of light is mandatory during the Vitamin B12/Folate test. Materials and Methods : We have conducted two experiments of identifying the extent of light’s influence when conducting the Vitamin B12/Folate test and also when specimens are under preservation. These experiments were progressed with various concentrations of patients’ specimens which were requested to our hospital in March 2012. The first experiment is to verify the results on Vitamin B12/Folate dependent on light exposure during the experiment. In the process, we have compared the results of light exposure/exclusion during the incubation process after the reagent division. The second experiment is about the impact of light exposure on the results on Vitamin B12/Folate during the preservation. For 1, 2, 7 days the light on the specimen were wholly blocked and were preserved under -15℃ temperature refrigeration. Then, we compared the results of light-excluded specimen and the exposed one. Results : When conducting first experiment, there were no noticeable changes in the Standard and specimen’s cpm, but for Vitamin B12, the average result of specimen exposed to light increased 7.8% compare to that of excluded one’s. Furthermore, in the significant level 0.05, the significance probability or the p-value was 0.251 which means it has no impact. For Folate, the result being exposed to light decreased 5.4%, the significance probability was 0.033 which means it has little impact. For the second preservation, the result was dependent on the light exposure. The first day of preservation of Vitamin B12, the clinical material exposed to light was 11.6%, second day clinical material exposed to light was 10.8%, seventh day clinical material exposed to light increased 3.8%, the significance probability of the 1st, 2nd, 7th day is 0.372, 0.033, 0.144 respectively, and which indicates that the 1st and 7th day seems to have no impact. For Folate’s case, the clinical material exposed to light has increased 1.4% but hardly had impact, 2nd day clinical material being exposed to light was 6.1%, 7Th day clinical material being exposed to light decreased 5.2%. The significance probability of Folate on the 1st, 2nd, 7th day is 0.378, 0.037, 0.217 respectively, and the 1st day and the 7th day seems to have no impact. Conclusion : After scrutinizing the impact of light exposure/exclusion, Vitamin B12 has no impact, while Folate seems to have no noticeable influence but light exclusion is recommended due to its significance probability of 0.033 when conducting experiment. During the preservation, the 2nd day result depend on the light exclusion seems to have impact or influence. However, to consider the complication of the experimental process, the experiment including technical errors is predictable. Hence, it is likely to have no impact of light. Nevertheless, it is recommendable to exclude the light during the long preservation as per the significance probability (p-value) of 1st and 7th day has been diminished.