Desenvolvimento de equipamentos baseados em microeletrônica embarcada para estudos avançados de nanomateriais: estudos fotoquímicos e de formação de complexos supramoleculares

Abstract

This research describes the development of essential tools for studies in nanoscience and nanomaterial synthesis, utilizing Arduino-based microelectronics. Two types of systems were investigated: photoreactors and a quartz crystal microbalance (QCM). The objective was to construct and validate benchtop photoreactors with diverse functionalities, along with a flowcontrolled peristaltic pump adapted to a QCM for complex real-time studies involving nanomaterials and biomolecules. Two benchtop photoreactors were built: a Multichannel Photoreactor for Microscale Processes (FMPM) and a Test Tube Photoreactor (FTE), both based on LED systems controlled by Arduino. The FMPM allows simultaneous investigations of photochemical reactions, with control over parameters such as pH, concentration, ionic strength, surface ligands, stirring, wavelength, irradiation intensity, time, and temperature. The FTE was developed for 15 mL tubes, with control over irradiation intensity and exposure time. Characterization of both systems was performed using chemical actinometry, with average power outputs of 50.35 mW (FMPM) and 34 mW (FTE). Additionally, the FMPM was successfully employed in the photochemical synthesis of silver nanoparticles (AgNPs), using stabilizing agents such as trisodium citrate dihydrate (TSC), polyvinylpyrrolidone (PVP), and poly(ethylene glycol) methyl ether thiol (HSPEG-OCH₃), as evidenced by absorption spectra. These results demonstrate the photoreactor’s efficacy in nanomaterial synthesis, significantly advancing the production of materials with exceptional properties. In addition to AgNP synthesis, both photoreactors were successfully applied in the photodegradation of methylene blue (MB) dye, while the FTE was also used to degrade safranine T (ST) and rhodamine B (RhB). In parallel, a Flow-Controlled Peristaltic Pump (BPCF) controlled by Arduino was developed for use with the QCM, enhancing its application in real-time complex interaction studies between nanomaterials and biomolecules. The adapted QCM system was used to investigate interactions between gold nanoparticles and an artificial membrane constructed on the quartz crystal, underscoring its potential for detailed molecular interaction studies.