Modelling of multi-component immunoassay kinetics - A new node-based method for simulation of complex assays

The behaviour of binding reactions in immunoassays can be predicted and studied by modelling methods. Simple antibody-analyte binding reaction kinetics can be simulated by e.g. a mechanistic assay model based on differential equations. However, the mathematical modelling becomes more complicated if multivalent-structured components are involved and the number of binding complexes increases. In this paper, a new node-based method to model complex binding reactions is introduced. The principle of this method is to construct a network of the initial components, reaction intermediates and end-products by forming a network of nodes. This network is then solved, node by node, breaking the initial problem into smaller partial problems, still obeying the laws of chemical reaction kinetics and without ignoring any parts of the problem. This method provides an easy and quick way to study complex binding reactions since simulation networks are simple to construct directly from the reaction scheme. This presented new "NODE"-method is compared with the well known mechanistic assay model.