BLT Stages

Abstract Bachelor Project FBT 2020-2021: The development of a Chlamydia trachomatis self test on a lab-on-chip system

This research project examines the effect of a buffer in a self-designed self-test for Chlamydia by Antelope Dx. The self-test will show whether a user has the sexually transmitted disease Chlamydia trachomatis. The buffer composition has been altered to obtain the optimal conditions for the assay. To test this buffer, a photonic chip is used, which is also present in the designed self-test. Previous studies have found that the use of self-testing has many advantages, but also many disadvantages. A large proportion of users feel that privacy and cost are positive criteria. In turn, accuracy and not being supported by a medical professional are disadvantages.

Before the buffer can be examined, the chip must be functionalized. During this process, a chip is functionalized using a polymer. Various antibodies are then added to the chip and these antibodies then bind to the chip. A block of silicone is attached to the chip and through this silicone, the buffer and the sample will flow. Then the buffers are tested on a self-designed bioassay, where the buffer flows over the chip, with the antibodies bound to it. The binding of analyte and change of medium flowing over the sensors causes a phase shift of the light passing through the sensors. This signal is detected and analysed. Different components in the buffers were compared with each other. A component A was compared with component B. Next, the concentration of three different components C, D and E, already present in the buffer, were tested to determine the optimum concentration of the different components. Then five different buffers were tested, each with a different pH. Two components, F and G, each with a different molecular weight, were then tested. For each molecular weight of the component, different concentrations were also examined. Finally, the optimal components are added together in a buffer. This buffer is compared with previous buffers.

A higher signal was obtained for component A, so that the final optimal buffer also contained this component. Component C shows the best results at a concentration of 150 mM. Components D and E show the best results at a concentration of 2,5 mM and 0,05 %, respectively. The optimal pH is 6, as the best results were achieved with this pH. Of the two components, F and G, only G was added in the final buffer. This component had the best results at the highest molecular weight with a concentration of 1 %. If the last obtained buffer is compared with previous used buffers, then it can be concluded from the obtained results that this is the optimal buffer.

From these results, it can be concluded that an optimal buffer was achieved. In the future, this buffer will be used to perform all following experiments.