Optimised distribution of proteins by porosity design of the carriers of diagnostics

The development and optimisation of lateral flow tests requires the increase of sensitivity, the reduction of the amount of reagents, and the reduction of the need for sample quantities. To achieve these objectives, the challenge for research and development lies in the provision of methods for the production of new membrane structures. These methods require the consideration of multiple influence parameters such as fluid properties, interface properties and structural properties. Simulation models of the test runs support the optimisation of existing membranes with regard to the demanded properties of the increase in sensitivity, the reduction of samples, and the reduction of the amount of reagents. The calculations lead to a better understanding of the physical processes and provide the manufacturer Sartorius with essential indications for an improved membrane design. Within the project, new simulation methods are developed in microstructured membranes to describe the spread of a fluid in porous membrane structures, to capture protein adsorption, and to optimise the flow channels. The simulations allow a detailed analysis of the penetration and of the propagation dynamics of the fluid, in dependence of the membrane properties, the interface properties and the fluid properties. As a result of the simulations, system parameters such as the porosity of the membrane, the structure of the ligaments, the network of canals, the contact angles, the surface tension and the protein concentrations can be predicted, which lead to an improvement of the membrane. Furthermore, the protein adsorption capacity can be predicted from the calculations. Based on the developed calculation models of the microstructure scale and a validation with data of process runs at Sartorius Stedim Biotech GmbH, a derivation of effective system parameters, for the use on the macroscale, is to be made in cooperation with the partner TinniT Technologies GmbH. Through aspired multiscale modelling, complete lateral flow tests are to be calculated for the newly designed membranes and are to be evaluated by comparison with experiments