All articles starting with P
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Photobiocatalysis
Photobiocatalysis is the integration of enzymatic catalysis with photochemistry, in which light drives or assists reactions by enzymes or photosynthetic whole cells, enabling selective radical transformations under mild conditions.
Photobiocatalysis with excited flavins and Ru complexes
Photobiocatalysis with excited flavins and Ru complexes is a branch of biocatalysis in which light promotes a flavin cofactor or a ruthenium complex into an excited state that forms radicals the enzyme steers with high stereoselectivity.
Photobiocatalysis with photosensitizer-enzyme pairs
Photobiocatalysis with photosensitizer-enzyme pairs is a mode of photobiocatalysis in which a light-absorbing photosensitizer supplies electrons, energy, or regenerated cofactors like NAD(P)H to an enzyme, classed as enzyme-photosensitizer coupled systems.
Photobiocatalytic radical C–H functionalization
Photobiocatalytic radical C–H functionalization is a synthetic strategy combining light-driven photoredox generation of radicals from C–H bonds with enzyme catalysis, using engineered thiamine diphosphate enzymes to control stereochemistry.
Photobiological hydrogen production
Photobiological hydrogen production is the generation of hydrogen gas by photosynthetic microorganisms, chiefly green algae and cyanobacteria, using sunlight to split water, an early-stage technology limited by oxygen sensitivity.
Photobiomodulation therapy
Photobiomodulation (PBM) therapy, long known as low-level laser therapy and marketed as red light therapy, uses low-power red or near-infrared light to relieve pain and reduce inflammation.
Photobioreactor
Photobioreactor (PBR): closed, illuminated vessel for controlled cultivation of microalgae and cyanobacteria; tubular, flat-panel, bag, and airlift types; higher productivity and strain control than open ponds but far higher capital cost.
Photobleaching
Photobleaching is the permanent loss of fluorescence by a fluorophore after extended light exposure, limiting imaging but also underpinning techniques such as FRAP that measure molecular transport in cells.
Photobook
A photobook is a book in which photographs make up a significant portion of the content, arranged as a cohesive work, and recognized today as a distinct artistic genre.
Photocaging
Photocaging is a chemical technique that inactivates a bioactive molecule by attaching a photoremovable protecting group, restoring its activity on demand by irradiation, first applied in 1978 to caged ATP.
Photocatalysis
Photocatalysis is a catalytic method in which a light-activated semiconductor particle absorbs photons and uses excited electrons and holes to drive redox reactions, underpinning solar fuel production, environmental remediation, and organic synthesis.
Photocatalytic [2+2] cycloaddition
Photocatalytic [2+2] cycloaddition is a light-driven reaction where a photocatalyst converts two alkene π bonds into a cyclobutane ring, a route thermally forbidden by orbital symmetry.
Photocatalytic aerobic oxidation
Photocatalytic aerobic oxidation is a light-driven chemical process in which a semiconductor photocatalyst transfers electrons and holes to oxidize organic compounds with molecular oxygen as the terminal oxidant.
Photocatalytic alkene isomerization
Photocatalytic alkene isomerization is a light-driven method for converting carbon–carbon double bonds between their E and Z forms, reaching Z-rich products that heating alone cannot deliver selectively.
Photocatalytic anti-Markovnikov hydroamination
Photocatalytic anti-Markovnikov hydroamination is a light-driven method for adding an N–H bond across an alkene so the amine ends up on the less substituted carbon, reversing conventional Markovnikov selectivity.
Photocatalytic borylation of alkyl halides
Photocatalytic borylation of alkyl halides is a family of light-driven reactions converting alkyl chlorides, bromides, and iodides into alkyl boronic esters via diboron reagents under mild conditions.
Photocatalytic C–H fluorination
Photocatalytic C–H fluorination refers to light-driven methods that convert carbon–hydrogen bonds to carbon–fluorine bonds, using photocatalysts like anthraquinone and decatungstate with Selectfluor or NFSI; the 2014 anthraquinone method was a landmark.
Photocatalytic C–H functionalization
Photocatalytic C–H functionalization is a set of synthetic methods in which light-activated catalysts convert carbon–hydrogen bonds directly into new carbon–carbon or carbon–heteroatom bonds without prefunctionalized substrates.
Photocatalytic carboxylation
Photocatalytic carboxylation is a set of light-driven chemical reactions that incorporate carbon dioxide into organic molecules to form carboxylic acids, using photoredox catalysis at room temperature instead of heat or stoichiometric metallic reductants.
Photocatalytic CO2 methanation
Photocatalytic CO2 methanation is the light-driven conversion of carbon dioxide and water into methane using solar energy, pursued as an alternative to conventional thermal methanation at 200 to 500 degrees Celsius.
Photocatalytic CO2 reduction
Photocatalytic CO2 reduction is a light-driven catalytic method in which semiconductor or molecular photocatalysts convert carbon dioxide into carbon monoxide, methanol, and methane, pursued as a route to solar fuels since 1979.
Photocatalytic CO2 reduction by cobalt polypyridyl complexes
Photocatalytic CO2 reduction by cobalt polypyridyl complexes is light-driven chemistry in which a cobalt catalyst with polypyridine ligands, a photosensitizer, and a sacrificial donor convert carbon dioxide into carbon monoxide or formate.
Photocatalytic decaging
Photocatalytic decaging is a bioorthogonal chemical strategy in which light-activated photocatalysts remove protecting caging groups, releasing bioactive molecules inside living cells; applications include protein labeling, proteomics, and prodrug activation.
Photocatalytic decatungstate C–H functionalization
Photocatalytic decatungstate C–H functionalization is a hydrogen atom transfer method in which photoexcited decatungstate, usually TBADT, abstracts hydrogen from C(sp³)–H bonds to form radicals that build C–C, C–N, and other bonds.
Photocatalytic defluorination of PFAS
Photocatalytic defluorination is a water-treatment process in which light-activated semiconductor catalysts break the strong carbon–fluorine bonds of PFAS forever chemicals, releasing fluoride and offering a destructive alternative to adsorption.
Photocatalytic defluorinative functionalization of PFAS
Photocatalytic defluorinative functionalization of PFAS is the use of light-activated catalysts to break carbon–fluorine bonds of persistent pollutants, either mineralizing them or forming functionalized products.
Photocatalytic degradation of plastics
Photocatalytic plastic degradation is a light-driven process in which a semiconductor catalyst generates reactive oxygen species that break polymer chains, mineralizing plastic or upcycling it into chemicals.
Photocatalytic deuteration
Photocatalytic deuteration uses light-activated catalysts to replace hydrogen atoms in organic molecules with deuterium, typically via hydrogen isotope exchange with heavy water, for labeling pharmaceuticals.
Photocatalytic E–Z isomerization of alkenes
Photocatalytic E–Z isomerization of alkenes is a light-driven method that converts the stable E (trans) geometry of a double bond into the less stable Z (cis) form using triplet energy transfer from a photocatalyst.
Photocatalytic hydrogen atom transfer
Photocatalytic hydrogen atom transfer (photocatalytic HAT) is a synthetic method in which an excited photocatalyst abstracts a hydrogen atom from a C–H bond, generating carbon radicals for bond formation.