Teh-Hua Tsai

This investigation of hydroxyl and polysiloxane absorption peaks in elastic polymer composites reveals significant spectral shifts within the fingerprint region of FTIR spectra. Using poly(vinyl butyral) (PVB) as the base polymer and poly(vinyl acetate) (PVAc) and poly(vinyl alcohol) (PVA) as reference materials, solvent effects on polymer–solvent interactions were systematically analyzed. Among the tested alcohol solvents, PEG 400 induced the most pronounced spectral changes, with the C=O stretching band shifting from 1740 to 1732 cm⁻¹ and the O–H band significantly broadening and downshifting to around 3300 cm⁻¹, reflecting strong hydrogen-bonding interactions. Wavelet-based noise reduction effectively enhanced the signal-to-noise ratio, reducing the baseline standard deviation by over 90%. This study introduces a novel noise-enhanced FTIR recognition model that integrates baseline noise metrics to improve detection sensitivity. The model successfully uncovers subtle structural variations in polymer–solvent systems that are typically masked by conventional FTIR techniques, advancing materials analysis and providing a robust framework for future FTIR-based diagnostics and material characterization.

Popular photoluminescent (PL) nanomaterials, such as carbon dots, have attracted substantial attention from scientists due to their photophysical properties, biocompatibility, low cost, and diverse applicability. Carbon dots have been used in sensors, cell imaging, and cancer therapy. Leek seeds with anticancer, antimicrobial, and antioxidant functions serve as traditional Chinese medicine. However, leek seeds have not been studied as a precursor of carbon dots. In this study, leek seeds underwent a supercritical fluid extraction process. Leek seed extract was obtained and then carbonized using a dry heating method, followed by hydrolysis to form carbon dot micelles (CD-micelles). CD-micelles exhibited analyte-induced PL quenching against Co²⁺ through the static quenching mechanism, with the formation of self-assembled Co²⁺-CD-micelle sphere particles. In addition, CD-micelles extracted metal ion through liquid–liquid extraction, with removal efficiencies of >90% for Pb²⁺, Al³⁺, Fe³⁺, Cr³⁺, Pd²⁺, and Au³⁺. Moreover, CD-micelles exhibited ABTS•⁺ radical scavenging ability and cytotoxicity for cisplatin-resistant lung cancer cells. CD-micelles killed cisplatin-resistant small-cell lung cancer cells in a dose-dependent manner with a cancer cell survival rate down to 12.8 ± 4.2%, with a similar treatment function to that of cisplatin. Consequently, CD-micelles functionalized as novel antioxidants show great potential as anticancer nanodrugs in cancer treatment.

Elastic polymer composite materials possess physical properties such as softness, durability, and heat preservation, making them suitable for designing flexible, snug, and highly ductile devices. While polymers are generally electrical insulators, they can become electrically conductive when doped with carbon powder. Carbon can strongly interact with polymers, enabling the composites to exhibit electrical conductivity through this adsorption process. By heating and melting the polymer and incorporating thin but heavily concentrated carbon powder, these composites can achieve electrical properties similar to those of conductors or semiconductors. This study examines the adsorption and electrical properties of elastic polymer composite materials, focusing on aspects such as resistance temperature characteristics and conductivity. The results indicate that electrically conductive elastic polymers have potential applications in electrothermal devices, thermostatic control systems, sensors, and variable resistors. Additionally, scanning electron microscopy (SEM) is employed to analyze the material’s structure for further research.

Silicon (Si) is the major material of semiconductor element. For semiconductor element producing, Si need to refined into high-purity silicon crystals, which has the approximate characteristics of intrinsic semiconductor, then doping 13th group or 15th group trace element. Producing the high-purity silicon crystals with well-lattice structure need a lot of energy and highly cost. Besides, the high-purity silicon is very hard and fragile which limits the scope of application. For this reason, this study added low-grade non-complete lattice silicon in the elastic polymer, and then doped with high concentrations of fine carbon powder. This material can be conductive by physisorption;therefore, it can be used to making semiconductors. Using this material to produce electronic components can significantly reduce the cost of purification and crystallization, saving energy at the same time. Moreover, because this elastic polymer materials containing silicon, which has soft, warm, and durable physical properties. With those properties, the design of the device could be more flex, full scalability and close to the skin.

A new cleaning agent for silicon contamination in the wafer dicing process was formulated in this research. Ammonium bifluoride was introduced as the main ingredient in the formula, and MSA and sulfuric acid were added as the solvent and buffer solution against metal corrosion. It was confirmed that the new formula cleaning agent could be used in the cleaning of silicon contamination from dicing. Silicon contamination is common in the wafer dicing process and consists of silicon powder and relevant metal particles during cutting, all of which are mixed with some adhesive residues. These contaminating particles on the IC surface are exposed to cleaning agents. However, while it is imperative to clean the wafer, the exposed surface is also vulnerable to damage from the solution. This further complicates the procedure because there is currently no ideal cleaning agent for the process. Our proposed formula hopefully provides an ideal chemical for use in wafer cleaning (SC-1, SC-2, BOE), since it uses a less toxic compound, ammonium bifluoride, which yielded good results during our experiments.

In this study, we constructed a recombinant Escherichia coli strain with different promoters inserted between the chromate-sensing regulator chrB and the reporter gene luxAB to sense low hexavalent chromium (Cr(VI)) concentrations (lux-expressing E. coli with the T7 promoter (T7-lux-E. coli, limit of detection (LOD) = 0.0005 mg/L) had the highest luminescence intensity or was the most sensitive for Cr(VI) detection, followed by E. coli with the T3 promoter (T3-lux-E. coli, LOD = 0.001 mg/L) and that with the SP6 promoter (SP6-lux-E. coli, LOD = 0.005 mg/L). All biosensors could be used to determine whether the Cr(VI) standard was met in terms of water quality, even when using thawing frozen cells as biosensors after 90-day cryogenic storage. The SP6-lux-E. coli biosensor had the shortest detection time (0.5 h) and the highest adaptability to environmental interference. The T7-lux-E. coli biosensor—with the optimal LOD, a wide measurement range (0.0005–0.5 mg/L), and low deviation (−5.0–7.9%) in detecting Cr(VI) from industrial effluents, domestic effluents, and surface water—is an efficient Cr(VI) biosensor. This unprecedented study is to evaluate recombinant lux E. coli with dissimilar promoters for their possible practice in Cr(VI) measurement in water bodies, and the biosensor performance is clearly superior to that of past systems in terms of detection time, LOD, and detection deviation for real water samples.

Research on gold nanoparticles (AuNPs) has often focused on their physical, chemical, and crystalline characteristics. Commercial AuNPs have been applied in the diverse fields of biomedicine, catalysis, photovoltaics, and sensing. In this study, we explored the various activities of AuNPs to widen their applicability. This paper presents a simple and rapid synthesis process of AuNPs with bacteria isolated from a gold mining area. We also investigated the optimization of reaction parameters for AuNP synthesis. The study results revealed that among the isolated strains, Bifidobacterium lactis and Escherichia coli demonstrated the highest capabilities of AuNP synthesis. The optimal pH values for AuNP synthesis by B. lactis (BLAuNPs) and E. coli (ECAuNPs) were 5.0 for 72 h of incubation and 8.0 for 24 h of incubation. The average particle sizes of ECAuNPs and BLAuNPs were 4.2 and 5.6 nm, respectively. Furthermore, these biogenic AuNPs were found to be stable with no aggregation after 3 months of storage. BLAuNPs and ECAuNPs exhibited high levels of antimicrobial, antioxidant, photocatalytic, and antityrosinase activity. Moreover, they were noncytotoxic to skin cells even at 100% melanin inhibitory concentrations. Considering the demonstrated multifunctional activities of AuNPs, BLAuNPs and ECAuNPs have promising potential for commercialization.

Coliform bacteria are indicators of water quality; however, most detection methods for coliform bacteria are time-consuming and nonspecific. Here, we developed a fluorescence in situ hybridization (FISH) approach to detect four types of coliform bacteria, including Escherichia coli, Klebsiella pneumoniae, Enterobacter aerogenes, and Citrobacter freundii, simultaneously in water samples using specific probes for 16S rRNA. This FISH method was applied to detect coliform bacteria in simulated water and domestic wastewater samples and compared with traditional detection methods (e.g., plate counting, multiple-tube fermentation (MTF) technique, and membrane filter (MF) technique). Optimal FISH conditions for detecting the four types of coliforms were found to be fixation in 3% paraformaldehyde at 4 °C for 2 h and hybridization at 50 °C for 1.5 h. By comparing FISH with plate counting, MTF, MF, and a commercial detection kit, we found that FISH had the shortest detection time and highest accuracy for the identification of coliform bacteria in simulated water and domestic wastewater samples. Moreover, the developed method could simultaneously detect individual species and concentrations of coliform bacteria. Overall, our findings indicated that FISH could be used as a rapid, accurate biosensor system for simultaneously detecting four types of coliform bacteria to ensure water safety.

Cr(VI) detoxification by biotreatment is considered one of the most practical detoxification methods, especially at low-to-medium concentrations. Although the capabilities of chromium-reducing bacteria and related enzymes in removing Cr(VI) have been explored, little is known about their differences in engineering applications. In this study, Ochrobactrum sp. CUST210-1 was isolated and its chromate reductase identified and separated as biological elements in biosystems developed for Cr(VI) removal. Results indicate that intracellular Cr(OH)_3(s) accounted for 88.01% of Cr(VI) reduction product, and a possible reduction mechanism was exposed. The chromate reductase in Ochrobactrum sp. CUST210-1 was ChrR protein, and its crystal structure was revealed. The toxicity of Cr(VI)-containing wastewater was decreased by 57.8% and 67.0% (at minimum) by the CUST210-1 strain and ChrR, respectively. The Ochrobactrum sp. CUST210-1 biosystem demonstrated good adaptability to pH (7–9), and the ChrR biosystem exhibited high removal efficiency (>98.2%) at a wide range of temperatures (25 °C–40 °C). The outlet Cr(VI) concentration of the CUST210-1 biosystem met the industrial discharge limit of 0.5 mg L⁻¹ when the inlet Cr(VI) concentration in the actual Cr(VI)-containing wastewater was −1. The stricter water quality standard of 0.05 mg L⁻¹ could be complied with by the immobilized ChrR biosystem when −1 Cr(VI) concentration was introduced. These developed biosystems can be used in the bioremediation of various Cr(VI)-contaminated wastewaters. Regarding capital costs, those of the CUST210-1 biosystem were higher. To our knowledge, this is the first report comparing differences in the economic and operational characteristics of bacteria and enzyme biosystems for Cr(VI) removal.