In conclusion, we demonstrated a portable and low-cost NIR device and a nanosensor barcode that enables levodopa detection. To quantify the benefits of using fluorescence in the NIR region, we created a simulation that can serve as a guide and framework for future developments in NIR fluorescence analytics. Our experiments demonstrated that for sensing with (6,5)-SWCNTs, Si PIN photodiodes exhibit at least comparable sensitivity to InGaAs PIN photodiodes. This suggests that custom-built devices designed for screening of (6,5)-SWCNTs could benefit from using these low-cost Si photodiodes more often instead of InGaAs photodiodes. In our case, the custom reader was capable of reliably measuring levodopa concentrations of 10 µM in blood serum, which is near the range of typical therapeutic concentrations of 2 µM to 7.6 µM. To measure lower concentrations with the barcode reader, an optimization of the optical and electronic setup is needed to enhance sensitivity towards small voltage changes. Another viable approach is to increase the selectivity of the SWCNT sensor in blood serum. This could be achieved, e.g. by passivating the SWCNT sensors, which would reduce the interaction between the SWCNT surface and blood components. Additionally, incorporating the SWCNTs inside a hydrogel would allow for the engineering of a porous structure designed to filter out most proteins while permitting smaller molecules, such as levodopa, to pass through. A hydrogel barcode is also desirable in the context of developing a platform for POC test strips, as it offers a more suitable alternative to solution-based screening methods. The barcode reader itself can be further miniaturized by using a smaller, one-dimensional stage. In addition, the oscilloscope could be replaced by a suitable circuit featuring a digital-to-analog converter (DAC) to generate the sine wave and an analog-to-digital converter (ADC) to convert the output voltage of the LIA into a digital signal. Both circuits, along with the stage, could be driven by a single microcontroller, extensively reducing the size and costs of the overall setup. These findings highlight the potential to develop NIR POC diagnostics based on lowcost Si PIN photodiodes and (6,5)-SWCNT-biosensors. Overall, this approach is not restricted to levodopa detection and can be used for other POC applications by simply changing the SWCNT barcode.