Quantitative Analysis of Formaldehyde Using UV‐VIS Spectrophotometer Pattern Recognition and Artificial Neural Networks

AI in analytical chemistry: Advancements, challenges, and future directions

This article explores the influence and applications of Artificial Intelligence (AI) in analytical chemistry, highlighting its potential to revolutionize the analysis of complex data sets and the development of innovative analytical methods. Additionally, it discusses the role of AI in interpreting large-scale data and optimizing experimental processes. AI has been fundamental in managing heterogeneous data and in advanced analysis of complex spectra in areas such as spectroscopy and chromatography. The article also examines the historical development of AI in chemistry, its current challenges, including the interpretation of AI models and the integration of large volumes of data. Finally, it forecasts future trends and the potential impact of AI on analytical chemistry, emphasizing the need for ethical and secure approaches in the use of AI.

UV-vis spectroscopic detection of formaldehyde and its analogs: A convenient and sensitive methodology

Formaldehyde is deemed to be an indispensable industrial product that has been widely applied in manufacture of resins, drugs, building materials, etc. It has been widely accepted that, nevertheless, residual formaldehyde will cause pathogen reactions, even leading to cancers like leukemia. Thus, a facile and efficient approach has been designed to achieve the determination of formaldehyde by ultraviolet and visible (UV-vis) spectrophotometry in liquid media. In detail, O-(carboxymethyl) hydroxylamine (C₂H₅NO₃·0.5HCl) is chosen as the detection reagent for the specific recognition of formaldehyde on account of its unique aminooxy (-O-NH₂) which can react with formaldehyde to form oxime bonds (O-NCH₂), accompanied with the only by-product of H₂O. Likewise, this simple and sensitive detection approach based on the chemical detection reagent C₂H₅NO₃·0.5HCl can also be applied to the determination of other aldehyde homologs with carbonyl groups including acetaldehyde, acetone, benzaldehyde, 1, 4-phthalaldehyde. As a result, all the UV absorbances of analytes display remarkable linear detection relationships. The limits of detection (LOD) and limits of quantitation (LOQ) values are in the range of 0.03-1.16 ppm and 0.03-5.81 ppm respectively, with RSDs of 3.27-3.75 %, evidencing the feasibility of our method to determine formaldehyde and its homologs by UV-vis spectrophotometry and auspicious prospects of practical applications.

Pentagram-Shaped Ag@Pt Core-Shell Nanostructures as High-Performance Catalysts for Formaldehyde Detection

High-performance HCHO sensors are of great importance in various application fields such as indoor air quality assessments. Herein, bimetallic Ag-Pt nanoparticles are synthesized as high-performance catalysts for ZnO-based gas sensors. Spherical aberration (Cs)-corrected transmission electron microscopy images with atomic resolution clearly indicate that the prepared nanoparticles exhibit a novel Ag@Pt core-shell nanostructure with a pentagram shape. For high-performance HCHO sensor construction, integrated micro-electrodes are first fabricated with the microelectromechanical system (MEMS) technology. Then, the hydrothermal route is used to self-assemble well-aligned ZnO nanowire arrays onto the sensing microregion. After that, the pentagram-shaped Ag@Pt nanoparticles are loaded onto the surface of ZnO nanowires with the inkjet printing technique to form MEMS sensors with Ag@Pt@ZnO as the sensing material. The thoroughly sensing experiments indicate that the Ag@Pt nanoparticles exhibit satisfied catalytic activation to HCHO molecules. The experimental observed detection limit of our sensor to HCHO reaches the parts per billion level. To elucidate the HCHO-sensing mechanism, the online mass spectrum (online MS) is utilized to analyze the components of exhaust gas stream of HCHO flowing through the Ag@Pt@ZnO material. The online MS indicates that with the Ag@Pt catalyst, HCHO molecules are partially oxidized to HCOOH molecules at low temperatures and are completely oxidized to CO₂ molecules at high temperatures.