Impact of Storage Temperature on Stability and Quantitative Determination of Human Serum Albumin Measured by Bromocresol Green Method

Abstract

Precise determination of serum albumin level is vital for detecting and managing liver, kidney, and inflammatory conditions. The present study aimed to evaluate the effect of different storage temperatures and durations on serum albumin levels. An analytical cross-sectional study was conducted involving twenty-six healthy participants between 22 and 29 years of age. Four milliliters of venous blood were collected from each participant, and serum was separated. Each serum specimen was divided into four portions and stored as given below and the albumin concentrations were measured using the Bromocresol Green method on the BS240 Clinical Chemistry Analyzer. Mean albumin values (±SD) obtained for (i) serum obtained immediately after separation (ii) serum stored for 6 hours at room temperature (iii) serum stored for 24 hours at +4°C and (iv) serum stored for 48 hours at −20°C were 4.74±0.20, 4.69±0.16, 4.74±0.21, and 4.45±0.31 g/dL, respectively. The results demonstrated a statistically significant reduction in albumin levels in serum stored at −20°C for 48 hours compared to serum analyzed immediately after separation (p<0.001). In the comparison between serum analyzed immediately after separation and serum stored at ambient temperature for 6 hours (p=0.512) or at +4°C for 24 hours (p=0.997), no statistically significant difference in albumin levels was observed. Among these conditions, serum stored at +4°C for 24 hours showed the closest agreement with the immediately analyzed serum. Serum albumin level should ideally be measured immediately after blood collection. If immediate analysis is not feasible, serum specimen should be stored at +4°C for up to 24 hours, as this condition showed a better stability than storage at ambient temperature for 6 hours.

KEYWORDS: Albumin, Serum, Temperature, Storage