Cracking down on vapochromic salts: unveiling vapomechanical stress in gas-sorbing platinum complexes.

This study explores the vapochromic and vapoluminescent behaviors of [Pt(tpy)Cl]PF host molecules (tpy = 2,2':6',2''-terpyridine) under acetonitrile (CHCN) vapor guest, challenging the conventional view that these phenomena arise solely from direct host-guest interactions. Our findings reveal a cooperative mechanism where mechanochromic surface perturbations prime the Pt(II) host for guest incorporation, leading to initial color and luminescence changes prior to significant structural alterations. While the color transition between the yellow [Pt(tpy)Cl]PF form and the red/orange [Pt(tpy)Cl]PF·CHCN form is reversible, repeated vapor cycling induces a loss of crystallinity, as indicated by diffraction peak broadening and emission shifts.

Tiny silver bullets: silver nanoparticles are insecticidal to Culicoides sonorensis (Diptera: Ceratopogonidae) biting midge larvae.

Insecticide formulations with safer environmental profiles and limited off-target effects are desirable to manage medical and veterinary pests. Silver nanoparticles are insecticidal against mosquitos, nonbiting midges, and other insects. The biting midge, Culicoides sonorensis Wirth and Jones, is a vector of agriculturally important pathogens in much of the United States, and this study aimed to examine the insecticidal properties of silver nanoparticles in larvae of this species.

Fatal Food: Silver-Coated Grain Particles Display Larvicidal Activity in .

Mosquitoes pose a significant risk to millions of people worldwide since they can transmit pathogens. Current methods to control mosquito populations include the use of synthetic pesticides. Nanotechnology may be a solution to develop new mosquito control.

Optical sensing of aqueous nitrate anion by a platinum(II) triimine salt based solid state material.

Selective and quantitative measurement of aqueous nitrate (NO) anion is achieved using solid [Pt(Cl-4-tpy)Cl]ClO salt (Cl-4-tpy = 4-chloro-2,2':6'2''-terpyridine), and as the salt supported on controlled porous glass. This detection method relies on the color change of the Pt(II) complex from yellow to red and intense luminescence response upon ClO exchange with NO due to concomitant enhancement of Pt⋯Pt interactions. The spectroscopic response is highly selective for NO over a large range of halides and oxoanions.

Harnessing Fe(III)-Carboxylate Photochemistry for Radical-Initiated Polymerization in Hydrogels.

Coordination of Fe(III) to carboxylates in polyuronic acid hydrogels was used to impart photochemical reactivity to polysaccharide-based hydrogels. This photochemical reaction was then used for light-initiated polymerization to create hydrogels with advanced mechanical and conductive properties by capturing the photogenerated radical with a monomer, either acrylamide, methyl methacrylate, or aniline. The photopolymerization of acrylamide using the Fe(III)-polyuronic acid was quantified in solution and the polymerization efficiency was determined under different conditions.

pH-Mediated Colorimetric and Luminescent Sensing of Aqueous Nitrate Anions by a Platinum(II) Luminophore@Mesoporous Silica Composite.

Increased levels of nitrate (NO) in the environment can be detrimental to human health. Herein, we report a robust, cost-effective, and scalable, hybrid material-based colorimetric/luminescent sensor technology for rapid, selective, sensitive, and interference-free NO detection. These hybrid materials are based on a square-planar platinum(II) salt [Pt(tpy)Cl]PF (tpy = 2,2';6',2″-terpyridine) supported on mesoporous silica.

Phase transformation induced mechanochromism in a platinum salt: a tale of two polymorphs.

Red crystals of [Pt(tpy)Cl]NO3·HNO3 show mechanochromic behaviour turning yellow when pressure is applied. The electronic character and spectroscopic signature of the red and yellow polymorphs change as a result of slipping of the molecular stacking planes in the solid state. The slippage alters the PtPt intermolecular distances from a linear stacked motif with <3.

A digital imaging method for evaluating the kinetics of vapochromic response.

This work describes the novel use of a cell phone camera and the L*a*b method (color space defined by the International Commission on Illumination) to characterize the color change in different vapochromic platinum(II) complexes in order to get quantitative and more reliable data. In this study, we have developed a semi-automatic CCA software that digitally analyzes images (e.g.

Robotic direct reading device with spatial, temporal, and PID sensors for laboratory VOC exposure assessment.

This study evaluated a novel robotic direct reading method that used a real-time location system to measure the spatial-concentration distribution of volatile organic compounds (VOCs) in a chemistry laboratory. The CEMWIP II is a custom-made sensor that measures VOCs, temperature, humidity, and location, sending data wirelessly in real time to a remote location for display and storage. In this study, the CEMWIP II device was mounted on a robotic platform to create a CEMWIP II-mobile platform.

Assessing flammable storage cabinets as sources of VOC exposure in laboratories using real-time direct reading wireless detectors.

Herein we present the results of measurements using wireless direct-reading photoionization detector-based gas sensors to quantify concentrations of vapors of volatile organic compounds (VOCs) in and around flammable storage cabinets containing common organic solvents, including acetone, dichloromethane, trichloroethylene, and benzene. Such cabinets are commonly employed in laboratories to contain flammable liquids. A sensor array was deployed in a series of flammable storage cabinets in working laboratories.

Analyte-responsive gated hollow mesoporous silica nanoparticles exhibiting inverse functionality and an AND logic response.

A multifunctional nanoparticle with designed selectivity was made using hollow mesoporous silica, ship-in-a-bottle synthesis of a crystalline solid-state detector, and protection of the crystal by acid-responsive nanogates. The system demonstrates the inverse application of the usual trapping of contents by the gate followed by their release. Instead, the gate protects the contents followed by selective exposure.

Highly Selective Colorimetric and Luminescence Response of a Square-Planar Platinum(II) Terpyridyl Complex to Aqueous TcO4(-).

Molecular recognition of an aqueous pertechnetate (TcO4(-)) anion is fundamentally challenging partly due to the charge-diffuse nature of this anion, which hampers design of new technologies for its separation and detection. To address this gap, simple salts of transition metal complexes that undergo a distinct spectroscopic change upon exposure to aqueous anions were explored. The Pt(II) complex [Pt(tpy)Br]SbF6 (tpy = 2,2';6',2″-terpyridine) undergoes a dramatic color change and intense luminescence response upon TcO4(-) uptake due to concomitant enhancement of Pt···Pt interactions.

Between red and yellow: evidence of intermediates in a vapochromic Pt(II) salt.

[Pt(tpy)Cl]ClO4·H2O (1·H2O) changes from red to yellow upon dehydration due to increased Pt···Pt distances. Spectroscopic, diffraction, gravimetric and calorimetric data demonstrate the presence of intermediates during hydration and dehydration which signifies surprising mechanistic complexity in the vapochromic response.