Measuring blood concentration is helpful in indicating compliance. Moreover, the acute rejection might occur when the whole blood circulating drug concentrations are too low. On the other hand, said when the whole blood circulating drug concentration is high then the risk of adverse drug side effects also increases.
In the maintenance of appropriate drug interactions, drug interactions also play an important role. Administration of inhibitors or inducers of the cytochrome P-4503A-dependent monooxygenase system can either increase or decrease or decrease Cyclosporin A and FK506 circulating concentrations. Moreover, if a nephrotoxic compound such as aminoglycoside antibiotic is co-administered with either of the compounds, there is a potential for additive toxicity. It would be important to measure aminoglycoside blood concentration to distinguish between toxicity and infection.
Pharmacokinetic properties have an influence on the levels of drug circulating in the bloodstream. There should be a balance between the rate of appearance into circulation and its removal, and any co-administered agents that will affect the two parameters will have a profound effect on drug concentrations and therefore clinical management (Kang &. Lee, 2009).
ELISA detects biological molecules through the use of enzyme labelled antigens and antibodies. Small quantities of antigens such as protein, hormones and peptides can be detected in a sample through antigen binding to a specific antibody, which is detected subsequently by a secondary enzyme-coupled antibody (Gan &. Patel, 2013). Non-specific binding can be measured by ELISA method.