How molecular architecture defines quantum yields.

Understanding the intricate relationship between molecular architecture and function underpins most challenges at the forefront of chemical innovation. Bond-forming reactions are particularly influenced by the topology of a chemical structure, both on small molecule scale and in larger macromolecular frameworks. Herein, we elucidate the impact that molecular architecture has on the photo-induced cyclisations of a series of monodisperse macromolecules with defined spacers between photodimerisable moieties, and examine the relationship between propensity for intramolecular cyclisation and intermolecular network formation.

Photochemical Action Plots Map Orthogonal Reactivity in Photochemical Release Systems.

The wavelength-by-wavelength resolved photoreactivity of two photo-caged carboxylic acids, i. e. 7-(diethylamino)-coumarin- and 3-perylene-modified substrates, is investigated via photochemical action plots.

Photo-induced synthesis of polymeric nanoparticles and chemiluminescent degradable materials flow chemistry.

We report the photo-induced, additive-free, continuous synthesis of polymeric particles using flow chemistry. Not only can these particles be formed under ambient conditions in a solely light-induced precipitation polymerisation, they can be prepared continuous flow techniques to up-scale the synthetic process. We carefully assess the flow chemical parameters and analyse the resulting particles quantitatively using scanning electron microscopy (SEM).

DNA labelling in live cells visible light-induced [2+2] photocycloaddition.

We introduce a visible light-driven ( = 451 nm) photo-chemical strategy for labelling of DNA in living HeLa cells the [2+2] cycloaddition of a styrylquinoxaline moiety, which we incorporate into both the DNA and the fluorescent label. Our methodology offers advanced opportunities for the mild remote labelling of DNA in water while avoiding UV light activation.

Microspheres from light-a sustainable materials platform.

Driven by the demand for highly specialized polymeric materials via milder, safer, and sustainable processes, we herein introduce a powerful, purely light driven platform for microsphere synthesis - including facile synthesis by sunlight. Our light-induced step-growth precipitation polymerization produces monodisperse particles (0.4-2.

Two Sides of the Same Coin: Light as a Tool to Control and Map Microsphere Design.

Herein, we establish the effect of intensity and wavelength on the size of microparticles formed via precipitation polymerization, employing photocrosslinkable prepolymers. Simultaneous measurement of backscattered laser irradiation enabled real-time tracking of particle growth and provides the ability to vary the LED intensity (λ = 415 nm) during various stages of particle growth. Critically, particle diameters can be controlled between 200 and 700 nm by varying the LED power from 73 to 0.

On-demand acid-gated fluorescence switch-on in photo-generated nanospheres.

Herein, we introduce a fast, additive-free, ambient temperature photochemical approach - utilising the novel Diels-Alder cycloaddition of a photo-active ortho-methylbenzaldehyde (oMBA) with a terminal alkyne - for preparing functional acid-sensitive profluorescent nano-/microspheres in one step. Not previously reported, the possibility of applying such a reaction in the context of particle synthesis provides new possibilities for particle design, where multi-step reactivity can be gated into distinct steps. First, a photochemically-gated particle formation step yields a material possessing a reactive, spring-loaded intermediate at every cross-linking point.

All Eyes on Visible-Light Peroxyoxalate Chemiluminescence Read-Out Systems.

Chemiluminescence (CL) reactions have been widely employed and explored over the past 50 years because they offer unique light emission upon a defined chemical stimulus. In this Minireview, we focus on peroxyoxalate (PO) compounds because they feature very high quantum yields tuneable over the entire visible spectrum, allowing for visible-light detection by the naked eye without the necessity for expensive analytical instruments. Although analytical methods have been extensively described, PO-CL read-out is a strongly emerging field with ample industrial potential.

A Photochemical Ligation System Enabling Solid-Phase Chemiluminescence Read-Out.

The peroxyoxalate chemiluminescence (PO-CL) reaction is among the most powerful and versatile techniques for the detection of hydrogen peroxide (H O ) and has been employed in various biological and chemical applications over the past 50 years. However, its two-component nature (peroxyoxalate and fluorophore) limits its use. This contribution introduces an innovative and versatile photochemical platform technology for the synthesis of inherently fluorescent PO probes by exploiting the nitrile imine-mediated tetrazole-ene cycloaddition (NITEC) reaction.