Stability of lyophilized human serum for use as quality control material in bhutan.

Quality control (QC) materials are crucial for internal quality control (IQC) and external quality assessment scheme (EQAS). However, many developing countries are disadvantaged by unavailability and high cost of commercial control material. Therefore, preparing home-made lyophilized human serum will be cost effective for used as a QC material in Bhutan. We prepared lyophilized QC material using serum collected from Bhutanese volunteers. The stability of lyophilized serum was studied at 3 selected conditions by analyzing at certain intervals. The results were statistically compared with initial values. The significant p values (<0.05) were seen in glucose, BUN, ALT, total bilirubin and protein at 2-8 °C but no significant difference were observed at -20 °C at the end of 9 months. We concluded that, home-made lyophilized human serum prepared without stabilizers could be used at least up to 9 months if stored at -20 °C and 7 months at 2-8 °C. Stabilizers and additives are necessary if the materials are to be used longer than 7-9 months.