Studies on the Optimum Reaction Time for Commercial Cholesterol kits

A comparative study on optimum reaction time for four commercial cholesterol kits has been carried out. The kinetics of the reaction mixture has been studied at a concentration of 200mg/dl. It is observed that evaluated concentrations are well within the recommended linearity range as claimed by the manufacturers. As per the claims of the manufacturers the endpoint for all the four kits A,B,C and D is five minutes. The kinetic reaction for Kit D suggests an incomplete reaction since optical density is observed to be climbing beyond recommended end point. Out of all these statistics the % error is most revealing since the % error recorded for kits A,B, C and D is -1.02, 0.66,0.57 and 9.06 respectively at an extended time of 20 minutes from the initiation of the reaction. It is pertinent to note that it has been mentioned by the manufacturers that the reading can be taken at any time after the manufacturer's recommended end point and before one hour. In this experiment we have recorded readings upto 20 minutes and do not know how it will behave beyond such time. Kits B and C show upward trend whereas kits A and D show the reverse, that is, downward trend. The downward trend is attributed to poor colour stability and there could be variety of reasons which need to be explored.