Photonics photodynamic therapy

Ogawa K, Kobuke Y (2008) Recent advances in two-photon photodynamic therapy. Anticancer Agents Med Chem 8 269-279... 

Gao D, Agayan RR, Xu H, Philbert MA, Kopelman R (2006) Nanoparticles for two-photon photodynamic therapy in living cells. Nano Lett 6 2383-2386... 

Figure 17.8 Two-photon photodynamic therapy (PDT) (a) simultaneous absorption of two near-infrared (NIP) photons raises the sensitizer to the S, excited state (b) sequential absorption of two photons, one from S0 and the other from T, raises the sensitizer to a higher excited state...

This review describes some of the recent developments in materials which exhibit enhanced two-photon absorption that can initiate photopolymerization or up-converted emission. Various optical methods including femtosecond time-resolved pump-probe experiments to characterize the two-photon properties are discussed. Finally, the applications of two-photon processes to optical power limiting, up-converted lasing, 3-D data storage, 3-D micro-fabrication, two-photon fluorescence microscopy and bio-imaging, and two-photon photodynamic therapy are presented. 

Kim S, Ohulchanskyy TY, Pudavar HE, Pandey RK, Prasad PN (2007) Organically modified silica nanoparticles co-encapsulating photosensitizing drug and aggregation-enhanced two-photon absorbing fluorescent dyes aggregates for two-photon photodynamic therapy. 

BhawaUcar JD, Kumar ND, Zhao CF, Prasad PN (1997) Two-photon photodynamic therapy. J Qin Laser Med Surg 15 201... 

Balaz M, Collins HA, Dahlstedt E, Anderson HL (2009) Synthesis of hydrophilic conjugated porphyrin dimers Pot one-photon and two-photon photodynamic therapy at NIR wavelengths. Org Biomol Chem 7 874—888... 

Ambjerg J, Jimenez-Banzo A, Paterson MJ et al (2007) Two-photon ab-sorption in tetra-phenylporphyeenes are porphycenes better eandidates than porphyrins for providing optimal optieal imrperties fm two-photon photodynamic therapy J Am Chem Soc 129 5188-5199... 

Silica nanoparhcles also have been developed for two-photon photodynamic therapy. Both, a novel two-photon fluorescent dye, 9,10-bis[4 -(4"-aminostyryl)styryl] anthracene (BDSA) and HPPH, have been incorporated into ORMOSIL nanoparticles made from VTES, using reverse microemulsion. The two-photon-induced intraparticle ERET, based on the use of two-photon fluorescent aggregates as donors and a photosensihzing drug as an acceptor, has been demonstrated [111]. 

Brevet, D., Basile, I., Maynadier, M., Vaillant, O., Mongin, O., Blanchard-Desce, M., Morere, A., Garcia, M., Durand, J.-O., and Raehm, L. (2011) Mannose-functionalized mesoporous silica nanoparticles for efficient two-photon photodynamic therapy of solid tumors. Angew. Chem., Int. Ed., 50 (48), 11425-11429. 

Ogawa K, Kobuke Y (2009) Design of two-photon absorbing materials for molecular optical memory and photodynamic therapy. Org Biomol Chem 7 2241-2246... 

Absorption of a photon to produce a triplet excited state (via intersystem crossing from the first excited singlet state) can lead to energy transfer to another molecule. The phenomenon is used in photography for sensitization of the red end of the visible spectrum. More recent uses are in photodynamic therapy, an... 

All physical properties of pyrylium salts (unsubstituted or substituted with alkyl and/or aryl groups) prove the aromaticity of these cations vibrational spectra [66], mass-spectral fragmentations [67], magnetic properties [68-70], and electronic absorption spectra [71]. It should be mentioned that there is a close similarity between the electronic absorption bands of pyrylium salts and those of benzene, easily recognized by the marked bathochromic effect of substituents in y-position of pyrylium salts on one of these bands. Two-photon absorption spectra of 2,4,6-triarylpyrylium cations [72] may be used in optical data storage, lasing, and photodynamic therapy. 

An additional class of nonlinear optical effects is that of multi-photon absorption processes. Using these process, one can create excited states (and, therefore, their associated physical and chemical properties) with a high degree of three-dimensional (3D) spatial confinement, at depth in absorbing media. There are potential applications of multi-photon absorbing materials in 3D fluorescence imaging, photodynamic therapy, nonlinear optical transmission and 3D microfabrication. 

Koo YE, Fan W, Hah H. Photonic explorers based on multifunctional nanoplatforms for biosensing and photodynamic therapy. Appl Opt 2007 46 1924-30. 

Porphyrins are an important class of -> electron-transfer ligands. Photosynthesis is primarily driven by chromophores (light-harvesting antenna and reaction centers) which consist of special assemblies of porphyrins. Porphyrins have been intensively studied for their possible applications, including their use as photonic materials, catalysts, photosensitizers for photodynamic therapy, receptor models in molecular recognition, and components of -> electrochemical sensors [v]. 

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