International Journal of Current Microbiology and Applied Sciences (IJCMAS)
IJCMAS is now DOI (CrossRef) registered Research Journal. The DOIs are assigned to all published IJCMAS Articles.
Index Copernicus ICI Journals Master List 2022 - IJCMAS--ICV 2022: 95.28 For more details click here
National Academy of Agricultural Sciences (NAAS) : NAAS Score: *5.38 (2020) [Effective from January 1, 2020] For more details click here

Login as a Reviewer

See Guidelines to Authors
Current Issues
Download Publication Certificate

Original Research Articles                      Volume : 7, Issue:10, October, 2018

PRINT ISSN : 2319-7692
Online ISSN : 2319-7706
Issues : 12 per year
Publisher : Excellent Publishers
Email : /
Editor-in-chief: Dr.M.Prakash
Index Copernicus ICV 2018: 95.39
NAAS RATING 2020: 5.38

Int.J.Curr.Microbiol.App.Sci.2018.7(10): 3287-3294

Influence of Freeze-Thawing and Storage on Human Serum Lipid Analytes
P.C. Ugwuezumba1, P. Nwankpa2*, F.C. Emengaha2, C.N. Ekweogu2, C.C. Etteh2 and O.G. Chukwuemeka3
1Department of Medical Physiology, 2Department of Medical Biochemistry, Imo State University, Owerri
3Department of Biochemistry, Michael Okpara University of Agriculture, Umudike Nigeria
*Corresponding author

Temperature and storage are important determinants of sample stability which is essential for getting credible concentrations of analytes including those of the lipids. This study examined the influence of freeze-thawing and storage on the concentration human of lipid analytes. The study was conducted using samples from One hundred (50 males and 50 females) randomly selected outpatient participants between the ages of 20 – 60 years. Collection of blood samples was done using the antecubital venipuncture. All procedures were in accordance with the guidelines of the Helsinki declaration on human experimentation. Serum sample of each subject was divided into five (5) aliquots. Three (3) aliquots were used for analysis of 7 days storage at -4⁰C, -20⁰C, and -70⁰C. One (1) aliquot was used for freeze-thawing analysis at -4⁰C, -20⁰C, and -70⁰C while the remaining aliquot was used for baseline measurement (control). The lipid analytes examined at various instances included Total Cholesterol (TC), Triglyceride (TG), High density Lipoprotein Cholesterol (HDL-C), Low-density Lipoprotein Cholesterol (LDL-C) and Very Low-density Lipoprotein Cholesterol (VLDL-C). The result showed a statistically significant difference in the concentration of TC, TG, HDL-C and LDL-C for both males and females when frozen at -4⁰C, significant difference in the concentration of TG and VLDL-C for males and TC, TG, LDL-C and VLDL-C for females when frozen -20⁰C. It showed no significant change in the concentration of all the lipid analytes except VLDL-C when frozen at -70⁰C for both males and females as well as no significant difference in the stability of lipid analytes after 7 days storage at -4⁰C, -20⁰C and -70⁰C when compared to immediate freezing-thawing cycles of samples at -4⁰C, -20⁰C and -70⁰C. In conclusion, -70⁰C is the optimum temperature for storage of lipid samples in order to maintain stability of the analytes. Also, maintenance of stability of lipid analytes may not be time-dependent but temperature-dependent. It is therefore recommended that additional studies be conducted on extended freezer storage of lipid samples to really ascertain the effect of extended duration in the maintenance of stability of lipid analytes.

Keywords: Freeze, Thaw, Lipid analytes, Temperature, Storage

Download this article as Download

How to cite this article:

Ugwuezumba, P.C., P. Nwankpa, F.C. Emengaha, C.N. Ekweogu, C.C. Etteh and Chukwuemeka, O.G. 2018. Influence of Freeze-Thawing and Storage on Human Serum Lipid Analytes.Int.J.Curr.Microbiol.App.Sci. 7(10): 3287-3294. doi:
Copyright: This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike license.