The qCamProto is an early hand crafted prototype of a qPCR / qLAMP device based on a PocketPCR and a webcam to read fluorescent signals. The prototype was built by Urs Gaudenz, GaudiLabs and first tested during the GlobalLAMP GlobalLAMP-Paris meetup in Paris . The results both for qPCR and qLAMP amplifications look very promising. The use of a webcam to read fluorescent can have advantages and disadvantages compared to sensing with a photodiode as discussed below.
qCamProto with a modified PocketPCR for heating and cooling. The heatblock was replaced by a 4 tube linear heatblock. The webcam is looking up to the heatblock, fixed with a 3D printed holder.
The webcam used is a 914519-3X0 (pulled form a HP laptop). The cam has a manual shutter (exposure) and manual gain option that is set to get a sensitive and stable reading.
The signal curves are recorded using a prototype software written in Processing. The webcam image is captures over USB. The signal regions are masked and the brightness measured and plotted vs time. The blue LEDs for exciting the fluorescence is activated by the PocketPCR for a short periode of time the end of the cycle (to prevent bleaching). In this crude prototype the reading and excitation is not synchronized well and recovered data needed to be cleaned to compensate for that.
First results of qPCR amplification using Bacterial 16s rDNA primers for Bacterial identification. 3 positive tubes with a bacteria template and 1 negative control (bacteria was in LB while negative control was just water).