An efficient imine-linkage colorimetric probe for specific recognition of saringas surrogate, diethylchlorophosphate

Sarin simulants show limited representativeness

In this study, we conducted colorimetric gas-phase tests on real sarin and compared the results with the most commonly used simulants under identical test conditions. Our findings indicated that reactivity extrapolation was not a reliable approach and that validation using the real toxic gas remained essential for a fair assessment of sarin sensors.

1,10-phenanthroline appended novel Schiff base as a selective fluorescent chemosensor for nerve agent stimulants

A simple, tailor-made, novel chemosensor based on 1,10-phenanthroline Schiff base incorporating N, N-Diethylamino salicylaldehyde (1) was designed and synthesized. The sensing ability of chemosensor 1 was tested via colorimetric, UV-Vis and fluorescence spectroscopy. Chemosensor 1 could effectively and specifically detect diethylchlorophosphate (DCP) in acetonitrile displaying naked eye colour change from pale yellow to dark yellow while fluorogenic colour changes from blue to pink fluorescence (365 nm UV lamp irradiation). The spectral changes corroborated the colorimetric results with appreciable bathochromic shifts of 44 and 75 nm in absorption and emission spectra respectively. With DCP, the spectral changes may be attributed to the reaction of the phosphorus group with the hydroxyl group which inhibits the ICT within the molecule. The colorimetric and spectral changes were reversed with the addition of triethylamine (TEA) signifying the reversibility of chemosensor 1. Significantly, the detection limit of 1 for DCP ions was evaluated to be 4.4 nM with the binding constant value of 1.9 × 104 M-1. Furthermore, chemosensor 1 showed excellent performance for convenient DCP detection via filter paper fabricated test strips.

Smartphones as a platform for molecular analysis: concepts, methods, devices and future potential

Over the past 15 years, smartphones have had a transformative effect on everyday life. These devices also have the potential to transform molecular analysis over the next 15 years. The cameras of a smartphone, and its many additional onboard features, support optical detection and other aspects of engineering an analytical device. This article reviews the development of smartphones as platforms for portable chemical and biological analysis. It is equal parts conceptual overview, technical tutorial, critical summary of the state of the art, and outlook on how to advance smartphones as a tool for analysis. It further discusses the motivations for adopting smartphones as a portable platform, summarizes their enabling features and relevant optical detection methods, then highlights complementary technologies and materials such as 3D printing, microfluidics, optoelectronics, microelectronics, and nanoparticles. The broad scope of research and key advances from the past 7 years are reviewed as a prelude to a perspective on the challenges and opportunities for translating smartphone-based lab-on-a-chip devices from prototypes to authentic applications in health, food and water safety, environmental monitoring, and beyond. The convergence of smartphones with smart assays and smart apps powered by machine learning and artificial intelligence holds immense promise for realizing a future for molecular analysis that is powerful, versatile, democratized, and no longer just the stuff of science fiction.