Objective

Once the aptamer has been successfully discovery, improve and tested, we’ll need a way to integrate into an IoT device. IoT has multiple requirements and we could extrapolate some of them into the measurement system; The system has to be affordable, automatic and the limit of detection must be under the range of the protein’s concentration in the air.

Although our first idea includes an opticalsystem to measure the protein present in the sample, this approach has three main limitations

1. The working electrode is made of carbon with gold nanoparticles. The carbon has a better electrochemical window than gold or silver (check this postfor more information) and gold are the ideal substrate to join DNA (It only have to be thiolated).

2. The auxiliary electrode is also made of carbon.

3. The reference electrode is made of silver.

The electrochemical system has been conceived to solve these difficulties.

qPCR

The real-time PCR can show the evolution and enrichment of your selection process. When the amount of different sequences is very high, like in the initial population, the fluorescence star to grow and reaches a peak before decreasing.

This happens because as the SELEX id performed, the number of different sequences are drastically reduced, therefore the amplification can be done as usual and the characteristic sigmoid curve finally appears.

This happens because as the SELEX id performed, the number of different sequences are drastically reduced, therefore the amplification can be done as usual and the characteristic sigmoid curve finally appears. With each round of selection, we are able to reduce the number of sequences until the ideal curve it's achieved.

Figure 5: Graph with the cicles of the rounds of qPCR agains Relative Fluorescence Units (RFU) for the diferents round of Selex.