Stability of Homemade Lyophilized Serum for use as a Quality Control Material for Cholesterol and Triglyceride Parameters

Abstract

Important control materials are used to achieve the quality of laboratory examinations.
Control materials can be obtained from commercial serum or can be made yourself in the
form of pooled sera. The control material that is usually used in clinical laboratories is a
commercial control material in the form of lyophilisate. However, the price is quite
expensive, so it is less efficient to use in laboratories that have a small average number of
examinations. The self-made lyophilized control material can be used as an alternative to
replace the manufacturer's control which is quite expensive. This study aimed to analyze the
stability of homemade serum lyophilisate as a control material for cholesterol and triglyceride
parameters for 8 weeks. This research is an experimental study using a time series design
research conducted at the Clinical Chemistry Laboratory, Department of Medical Laboratory
Technology, Poltekkes, Ministry of Health, Surabaya, in October 2021-May 2022. Blood
serum is processed using the freeze dried technique to obtain a lyophilized form. Lyophilized
serum was stored at 2-8°C and dissolved using aquabides every week to check cholesterol
and triglyceride levels. In the Levey-Jennings chart cholesterol and triglyceride levels did not
deviate from 2SD during storage. Regression test showed that storage time had an effect of
0.4% on cholesterol levels and 55% effect on triglyceride levels. The results of the study
concluded that the homemade serum lyophilisate was stable for 8 weeks of storage.