Comparative analysis of random blood glucose levels in serum, plasma and whole blood using glucose oxidase and hexokinase methods under spectrophotometric and electrochemical techniques

Abstract

Diabetes is, a condition associated with the impairment of the body’s ability to produce or utilise the hormone insulin. This leads to abnormal metabolism of carbohydrates and elevated levels of glucose in the blood. This serious non-communicable disease has been on the rise in Kenya partly because many people are not aware that they are diabetic since there are no serious early symptoms associated with the disease. It is estimated that the prevalence of diabetes in Kenya ranges from 2.7% (rural settings) and 10% (urban areas) affecting both the affluent and non-affluent population. It is expected that the actual numbers could be higher since many cases go unreported for lack of regular screening in the general population. In Kenya there is no study that has been conducted to compare the performance of current blood glucose testing methods being used. The suitability of serum or plasma as alternatives to whole blood has also not been well researched. The sample of choice for glucose testing has always been whole blood, either in fluoride or from a finger prick. The aim of the study was to compare the results obtained from these three sample types (whole blood, serum and plasma) using two methods: glucose oxidase and hexokinase methods. The investigation was carried out using 299 study subjects that included 149 diabetic patients attending diabetic clinic either for management, diagnosis or monitoring of blood sugar and 150 healthy individuals in the blood donation centre at Kenyatta National Hospital Nairobi County. The analytical instruments used were glucometers and a spectrophotometer to compare blood glucose levels in serum, plasma and whole blood using electrochemical and spectrophotometric platforms. While comparing the serum and plasma glucose concentration using hexokinase method under electrochemical and spectrophotochemical platforms, the mean difference for the two protocols was 0.145 which was found to be statistically insignificant (p=0.342) using paired T-test. Similarly while comparing the same using glucose oxidase method under the electrochemical and spectrophotochemical platform, the mean difference for the two protocols was 0.012 which was found to be statistically insignificant (p=0.135) using paired T-test. The results revealed that the two methods used in glucose concentration analysis were similar irrespective of the method or sample used. There was no significant difference in their means. Either of the two methods can be used interchangeably in the analysis of glucose and either serum or plasma in fluoride can be used as a specimen of choice.