Three research groups from the GAMER Lab, composed of Bachelor of Science in Chemical Engineering students, successfully defended their undergraduate theses for the academic year 2025–2026. The defenses showcased advanced work in sensing technologies and environmental remediation, reflecting the group’s strong research direction in materials-based solutions to water and environmental challenges, April 27, 2026, at the Roque Ruaño Building.

Regie Erl I. Dulos, Lorenz Dominic A. Cabanatan, and Gian Carlo M. De Guino presented their work titled “L-cysteine-functionalized chitosan capped silver nanoparticles for smartphone-based colorimetric sensing of Fe³⁺ ions in water.”

Their system integrates nanoscale surface chemistry with accessible digital detection. Chitosan served as a stabilizing and biocompatible matrix for silver nanoparticles, while L-cysteine introduced thiol and amine functional groups that selectively bind Fe³⁺ ions. This interaction induces aggregation of AgNPs, producing a measurable color shift due to localized surface plasmon resonance changes.

Quantification was achieved through smartphone image capture followed by RGB channel analysis, establishing a calibration curve for Fe³⁺ concentration. The group evaluated sensitivity, selectivity against competing ions, and detection limits, demonstrating that the platform can serve as a low-cost alternative to spectrophotometric techniques. The approach supports field-deployable monitoring, particularly for resource-limited settings where rapid screening of heavy metals is required.

Kevin Christian Q. Bacay, Johnzelle G. De Villa, and Hannah Sofia B. Magnaye defended their thesis titled “Composition–activity relationships in NH₂-UiO-66(Ce)/g-C₃N₄/MoS₂ ternary photocatalysts for visible-light degradation of tetracycline in water.”

Their research addressed a key limitation in photocatalysis, which is rapid recombination of photogenerated electron–hole pairs. By constructing a ternary heterojunction, the group engineered interfacial charge transfer pathways that enhance carrier separation and extend light absorption into the visible region.

Systematic variation of component ratios enabled identification of optimal compositions that maximize photocatalytic activity. Kinetic analysis revealed improved degradation rates of tetracycline, while radical scavenging tests provided insight into dominant reactive species such as •OH and O₂⁻•. The study also examined structural and optical properties through characterization techniques, correlating band alignment and surface area with catalytic performance.

This work contributes to a deeper understanding of how multi-component systems can be tuned to target persistent pharmaceutical pollutants, a growing concern in wastewater streams.

Andrei Dominique G. Peralta, Wendell John D. Ramos, and Janella Nicole B. Roque presented “Facile Room-Temperature Synthesis of NH₂-UiO-66(Ce) for Congo Red Adsorption in Water.”

Their study focused on simplifying synthesis conditions while maintaining material performance. Conventional preparation of NH₂-UiO-66(Ce) often requires elevated temperatures and prolonged reaction times. The group developed a room-temperature route that reduces energy input and processing complexity, supporting more scalable production.

The synthesized material was evaluated for adsorption of Congo Red, a representative azo dye known for its persistence and toxicity. Adsorption studies included equilibrium isotherms and kinetic modeling, with results indicating strong affinity and rapid uptake. Functional amine groups on the framework contributed to electrostatic interactions and possible hydrogen bonding with dye molecules.

Each group exhibited careful integration of synthesis, characterization, and performance evaluation, supported by data-driven interpretation. The diversity of topics reflects a coherent research direction centered on water quality, spanning detection, degradation, and removal of contaminants.