2025 ICIEST

This research seeks to develop an innovative 3D-printed biosensor for the rapid and accurate detection of Escherichia coli (E. coli) bacteria in water samples. The proposed biosensor will incorporate a flow cell design, which allows continuous monitoring and efficient detection of E. coli in real-time. The sensor will be fabricated using conductive polymer-based materials integrated with specific biological recognition elements to ensure high sensitivity and specificity. The 3D printing technology will be utilized to create a precise and reproducible flow cell structure, optimizing the sensor's functionality and scalability. The research will proceed through several key phases: designing and simulating the flow cell structure, selecting and functionalizing the sensing materials, fabricating the biosensor using 3D printing techniques, and conducting extensive testing with water samples containing various concentrations of E. coli. This research will establish a foundation for future advancements in portable and effective biosensing devices for early detection of bacterial contamination.

Fossil fuels contribute to air pollution and drive climate change. Transitioning to solar energy offers a cleaner alternative. Perovskite solar cells are a promising advancement, potentially exceeding silicon cell efficiencies with simpler, cost-effective manufacturing. This research demonstrates the feasibility of electricity generation using a solution-processed perovskite solar cell under low light in the room building. The fabricated cell achieved an open-circuit voltage of 1.49V and a short-circuit current density of 5.15 mA/cm². A maximum power conversion efficiency of 18.67% was obtained under only around 10% of actual one sun light intensity. Such a high obtained efficiency of solar cell fabricated using inexpensive materials under low light intensity has become our current work novelty. These results highlight the potential of cost-effective perovskite solar cells for indoor and ambient light energy harvesting, supporting a shift towards sustainable energy solutions.

The increasing prevalence of pathogenic Escherichia coli (E. coli) in water and food sources poses a significant threat to public health, necessitating the development of rapid and accurate biosensor detection methods such as aptamerbased biosensors due to their high specificity and sensitivity. Aptamers are nucleic acids that can bind with high affinity and specificity to a range of target molecules. In this study, 1,000 shuffled variants of a known aptamer (PDB ID: 2AU4) were generated and evaluated for stability using RNAfold and RNALfoldz based on minimum free energy (MFE). The five most stable sequences were selected and analyzed for their secondary and tertiary structures using RNAComposer. The target protein, Shiga toxin (Stx, PDB ID: 1C48), was modeled with AlphaFold 3 and validated through Ramachandran plot analysis. Molecular docking using the HDOCK server revealed aptamer-protein binding interactions, offering insights into the structural features that influence binding specificity and stability. In conclusion, this research bridges theory for future applications, thereby establishing a theoretical framework to support the future development of aptamer-based biosensors targeting E. coli O157:H7.

In this project, triisopropylsilylethynyl-pentacene (TIPS-pentacene) will be utilized as a semiconducting polymer matrix for the preparation of biosensors based on organic field-effect transistor (OFET) structure. A thin layer of TIPS-pentacene can be easily formed on a silicon substrate through solution processable technique. Through polymer blend method which allows synergistic combinations of stacking configurations of multiple polymers energy levels which will enhance overall charge transport. Novel pentacene derivatives will also be proposed using machine learning method and computational study for synthesizing new narrow energy band gap polymer matrix. Analytical techniques, such as ultraviolet-visible (UV-Vis) spectroscopy will be used in the characterization of the materials properties. The proposed biosensor based on integration of biological compound into OFET will facilitate the government.