Photodynamic therapy PDT What is PDT The first

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Photodynamic therapy (PDT)

Photodynamic therapy (PDT)

What is PDT? The first observation: bacterial colonies are killed when dyed by eozin

What is PDT? The first observation: bacterial colonies are killed when dyed by eozin (O. Raab, 1900). Definition (H. von Tappeiner, 1904): Cell inactivation in the presence of • photosensitizer • visible light • oxygen

The first utilisations of PDT First therapeutic experiments (H. von Tappeiner, 1905 -1911). Porphyria:

The first utilisations of PDT First therapeutic experiments (H. von Tappeiner, 1905 -1911). Porphyria: consequences of impared degradation of porphyrins Enhanced accumulation of porphyrins in malignant tissues detected by fluorescence (~1960) First modern therapeutic applications Dougherty, 1968. , Roswell Park Memorial Hospital Buffalo, N. Y.

Depth of penetration of visible light in soft tissues

Depth of penetration of visible light in soft tissues

Typical photosensitizer families

Typical photosensitizer families

Typical absorbance and fluorescence of porphyrins

Typical absorbance and fluorescence of porphyrins

Diagnostic application

Diagnostic application

abszorbancia, transzmittancia, relatív egységek Therapy Abszorbancia Terápiás szűrő transzmittanciája 300 400 500 600 hullámhossz,

abszorbancia, transzmittancia, relatív egységek Therapy Abszorbancia Terápiás szűrő transzmittanciája 300 400 500 600 hullámhossz, nm 700 800

Characteristic absorption spectra porphyrin chlorin bacteriochlorin

Characteristic absorption spectra porphyrin chlorin bacteriochlorin

Schematic representation of PDT

Schematic representation of PDT

Hem biosynthesis

Hem biosynthesis

PDT in therapy of malignancies Curative application only for small depth (initial stage) occurencies

PDT in therapy of malignancies Curative application only for small depth (initial stage) occurencies Palliative applications Adjuvant therapy after surgery Diagnostic application during surgery

Typical applications against malignancies • • • Skin cancers Urology: bladder carcinoma (prostate) Gastroenterology:

Typical applications against malignancies • • • Skin cancers Urology: bladder carcinoma (prostate) Gastroenterology: Barrett esophagus Brain surgery Head and neck surgery Pulmonology

PDT in non-malignant diseases • Age related (wet) maculadegeneration • Psoriasis • To hinder

PDT in non-malignant diseases • Age related (wet) maculadegeneration • Psoriasis • To hinder restenosis after balloon angioplasty • Antibacterial applications • Cosmetic applications

Former research topics connected with PDT in the Department • Characterization of potential new

Former research topics connected with PDT in the Department • Characterization of potential new photosensitisers (absorption and fluorescence spectra, triplet absorption spectrum and lifetime, quantum efficiency of singlet oxygen generation) • Effect of the microenvironment on the characteristics of photosensitisers • Measurement of diffusion of singlet molecular oxygen • Studies on the flexibilty of biological membranes.

Triplet – triplet absorption spectra of anthracene 0. 020 n-Hexán n-Heptadekán DMPC 0. 015

Triplet – triplet absorption spectra of anthracene 0. 020 n-Hexán n-Heptadekán DMPC 0. 015 A 0. 010 0. 005 0. 000 390 400 410 420 (nm) 430 440

Triplet lifetime of prorphyrin in phospholipid membranes aerated conditions oxigen excluded o A 10

Triplet lifetime of prorphyrin in phospholipid membranes aerated conditions oxigen excluded o A 10 C 0, 03 o 20 C o 30 C A o 40 C 0, 02 26°C 35°C 45°C 55°C 0, 02 o 60 C 0, 01 0, 00 0 1 2 3 idő ( s) 4 5 0 0, 1 0, 2 0, 3 idő (ms) 0, 4 0, 5