NIR Laser Integration of Photodetector on 3D Printed Chamber for Colorimetric Biosensing

In this work, gold nanoparticles (Au NPs)/indium‐zinc‐oxide (IZO) nanocomposite visible photodetector (PD) is directly prepared by near‐infrared (NIR) laser‐annealing on a 3D‐printed substrate to form an integrated colorimetric sensor. After a surface planarization process, using a low power laser treatment without damaging the substrate, Au NPs are formed from the Au thin layer (6 nm) on 3D‐printed resin substrate by laser‐assisted dewetting process. Also, the UV–vis photoresponsivity is compared by tuning different NIR laser power intensity for sol‐gel IZO curing. By investigating the temperature profile of each laser annealing process and the surface morphology of Au NPs/IZO nanocomposite film, the optimized PD is then integrated with a 3D‐printed sensing chamber for successfully demonstrating urea detection varied from 1, 5, 10, 25 and 50 × 10−3 m, which refer to the salivary urea concentrations for healthy and chronic kidney disease groups. A gold nanoparticle/indium‐zinc‐oxide visible photodetector is prepared by near‐infrared laser annealing on a 3D‐printed substrate. As a photodetecting cover, it can be easily integrated with a 3D‐printed chamber for colorimetric biosensing. Finally, urea detection varying from 1, 5, 10, 25 to 50 × 10−3 m referring to the salivary urea concentrations for chronic kidney disease groups can be demonstrated.