Photochemistry of Supramolecular Complexes between Cucurbit[n]urils and Photosensitizers
Fecha
20182018
Institución
Resumen
Improving the overall performance of photoactive drugs used in Photodynamic therapy (PDT)
continues to be an essential goal in this area of research. There are continued efforts from
several groups around the world to develop new PDT drugs.1 Our group has been interested in
using a supramolecular strategy to take advantage of the encapsulation properties of a family
of macrocycles called “Cucurbit[n]urils” and improve the photoactivity of well-known
molecules.
Cucurbit[n]urils (CB[n], n = 5-8, 10, 13, 15) are a family of molecular containers that show
strong potential to improve drug delivery and protect the drugs from degradation. Moreover,
drug delivery is easily achieved by competitive displacement with biomolecules or other
drugs. Following pioneering work by J. C. Scaiano and Hermenegildo Garcia on the
encapsulation of photosensitizers (M. González-Bejar et al 2009, Langmuir, 25 10490), our
group has investigated the photochemistry of supramolecular complexes between CB[n]s and
well-known photoactive molecules. Such complexes show interesting properties for potential
applications in PDT, e.g. enhanced singlet oxygen generation, enhanced fluorescence,
protection from enzymatic degradation, decreased photobleaching, permeability through the
cell membrane, and control on electron-transfer reactions and singlet oxygen generation
depending on the type of macrocycle (J. Robinson-Duggon et al 2018, Isr. J. Chem.,
10.1002/ijch.201700093). Some recent applications such as a singlet oxygen reversible switch
(J. Robinson-Duggon et al 2017, J. Phys. Chem. C, 121, 21782) will be discussed.
The authors thanks CONICYT for the financial support through their FONDECYT research program
(Grant Nº1160443).