트롬보프라스틴의 보존법에 관한 연구

Abstract

Thromboplastin is one of the most widely used biological products in our country; and like most biolo· gical products it is quite expensive and it is difficult to obtain a proper commercial product of it. If it is reconstituted with dist illed water it must he used within hours and the remainder is discarded even though the instruction of the make-r indicates that they are stable for some days. Moreover there is usually small number of daily requests for prothromhin time tests in smalllaLoratories, and considcrnlilc amount of reconstituted thromboplastin, therefore. would be discarc!c'd. It is quite apparent that large amount of recnnst itutcd thromboplastin would become useless for this reason unless otherwise treated to save its sensitivity longer than several hours after reconstitution. In order to find a suitable method of its storngc, which onablr-s to maintain its sensitivity we performed a series of r-xpr-rimeut s. sur'h as fre('zing, lyophilizing and several others. First trial was to sec the cffrct of fre('zing store; thn t is reconstituted remainder of th romboplasrins were stored [or zen up to 1~ days and in the meantime the prothrombin time tests were performed every day with the [rozr-u-storcd sample. Thromboplastins were thawed whenever we use it at room temperature and evaluate the' scnsitivit y of them both on the normal and almormal plasma. Second trial was to observe the results when we clevide them into several parts of aliquots in Kahn tubes to keep them in refrigerator or deep freezer for one through ten days, With these stored thromboplastin, prothrombin time were checked every day to see the fluctuations in the thromboplastin sensitivity if there is any. When we were following this method, we were partieulary interested in the way how to thaw the frozen thromboplastin since varieties of thawing procedure would hring about different results; for example, thawing them at water bath or at room temperature may perhaps results in different ways. Third trial was to re-Iyophilize the reconstituted thromboplastin. The reconstituted thromboplastin were lyophilized nnce again and the changes in their sensitivity were evaluated in accordance with prothrombin time. Fourth trial was to evaluate the effects nf repeated freezing and thawing on the stability of thromboplastins. The results made from the this study arc as follows. First, the remainders of daily reconstituted thromboplastin left over being used is not adequate for prothrombin time test even though stored in deep freezer. Only 2 days of storage is acceptable as the maximum of its allowance limit, if forced to use again. Second, the best method for to store reconstituted is that thromboplastin is divide into several aliquots and storing in a deep freezer. And the stability of thromboplastins was varia hlc among the various products of thromboplast ins. Third, the sensitivity of thromboplastin to standard coagulation factor deficient plasmas are also variable among the products examined. Fourth, rclyophilization of reconstituted thromboplastin, is not acceptable for storage. Fifth, the prohlem how to thaw the frozen thromboplastin is insignificant and not affected whether the thromboplastin is thawed in room temperature or in water bath.