UVA-Triggered Drug Release and Photo-Protection of Skin

Light has attracted special attention as a stimulus for triggered drug delivery systems (DDS) due to its intrinsic features of being spatially and temporally tunable. Ultraviolet A (UVA) radiation has recently been used as a source of external light stimuli to control the release of drugs using a “switch on- switch off” procedure. This review discusses the promising potential of UVA radiation as the light source of choice for photo-controlled drug release from a range of photo-responsive and photolabile nanostructures via photo-isomerization, photo-cleavage, photo-crosslinking, and photo-induced rearrangement. In addition to its clinical use, we will also provide here an overview of the recent UVA-responsive drug release approaches that are developed for phototherapy and skin photoprotection.

Cycloreversion performance of coumarin and hetero-coumarin dimers under aerobic conditions: unexpected behavior triggered by UV-A light

Photochemical [2+2]-cycloadditions of coumarin-like monomers are the textbook paradigms of photo-formation and photo-cleavage reactions.

Light-induced modulation of DNA recognition by the Rad4/XPC damage sensor protein

Rad4/XPC DNA damage sensor protein specifically binds to a photocleavable NPOM-DNA adduct, and this recognition is abolished upon photo-cleavage of NPOM.

Synthesis, Characterization and Biological Studies of Novel Schiff Base viz. Bis-1,1'-(pyridine-2,6-diyldieth-1-yl-1-ylidene) biguanidine and Their Transition Metal Complexes

Novel Schiff base and its two transition metal complexes derived from the condensation reaction of 2,6-diacetylpyridine with biguanide, characterized by 1H NMR, IR and elemental analysis. The ligand and its cobalt(II) and nickel(II) complexes showed potent DNA photo-cleavage activity. Antimicrobial activity of this Schiff base and its cobalt(II) and nickel(II) complexes against bacteria and fungi viz. S. aureus, K. pneumoniaae and A. niger, Trichophyton rubrum, respectively was evaluated in terms of zone of inhibition.

Co-organizing synthesis of heterogeneous nanostructures through the photo-cleavage of pre-stabilized self-assemblies

The photo-cleavage of a pre-stabilized self-assembled nanostructure targets metastable assemblies leading to exotic heterogeneous nanostructures that are inaccessible through conventional synthesis.