mTHPC pharmacokinetics following topical administration

Johansson, A; Svensson, J; Andersson-Engels, S; Bendsoe, N; Svanberg, K; Bigio, I; Alexandratou, E; Kyriazi, M; Yova, D; Grafe, S; Trebst, T

dc.contributor.author	Johansson, A	en
dc.contributor.author	Svensson, J	en
dc.contributor.author	Andersson-Engels, S	en
dc.contributor.author	Bendsoe, N	en
dc.contributor.author	Svanberg, K	en
dc.contributor.author	Bigio, I	en
dc.contributor.author	Alexandratou, E	en
dc.contributor.author	Kyriazi, M	en
dc.contributor.author	Yova, D	en
dc.contributor.author	Grafe, S	en
dc.contributor.author	Trebst, T	en
dc.date.accessioned	2014-03-01T02:50:33Z
dc.date.available	2014-03-01T02:50:33Z
dc.date.issued	2006	en
dc.identifier.issn	16057422	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/35138
dc.subject	Absorption spectroscopy	en
dc.subject	Fluorescence imaging	en
dc.subject	Fluorescence spectroscopy	en
dc.subject	mTHPC	en
dc.subject	Pharmacokinetics	en
dc.subject	Photodynamic therapy	en
dc.subject.other	Fluorescence imaging	en
dc.subject.other	Fluorescence spectroscopy	en
dc.subject.other	MTHPC	en
dc.subject.other	Skin carcinomas	en
dc.subject.other	Absorption spectroscopy	en
dc.subject.other	Fluorescence	en
dc.subject.other	Hemoglobin	en
dc.subject.other	Medical imaging	en
dc.subject.other	Patient treatment	en
dc.subject.other	Photodynamic therapy	en
dc.subject.other	Pharmacokinetics	en
dc.title	mTHPC pharmacokinetics following topical administration	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1117/12.647602	en
heal.identifier.secondary	http://dx.doi.org/10.1117/12.647602	en
heal.identifier.secondary	60940C	en
heal.publicationDate	2006	en
heal.abstract	Measurements of concentration of sensitizers for photodynamic therapy can provide important information in the dosimetry planning and can also give input to the optimal time for treatment. There has been skepticism towards fluorescence techniques for this purpose, as the signal depends on the fluorescence yield and optical properties of the tissue. Absorption based techniques, lack on the other hand, often the sensitivity required for many sensitizers with relative weak absorption in a wavelength region where hemoglobin absorption is dominant. A direct comparison between absorption and fluorescence techniques for measuring mTHPC concentration after topical application on hairless SKH-1 mice bearing skin carcinomas has been performed. 20 μl/cm2 of m-THPC thermogel (0.5 mg m-THPC/ml) were applied on normal and tumor area and the concentration of mTHPC was measured at 4 and 6 hours after drug application by two methods: 1. A fluorescence imaging system capturing images at two wavelengths (500 and 650 nm) following 405 nm excitation. Signals from different regions of interest were averaged and the intensity ratio at 650 to 500 was calculated. 2. A diffuse reflectance spectroscopy system with a fiber separation of 2 mm, providing the absorbance at 652 nm. Both systems provided consistent results related to the photosensitizer concentration. The methods show a remarkable difference in the concentration of photosensitizer in normal skin and tumor. No significant difference in mTHPC concentration in tumor could be observed between the 4 and 6h groups after drug application.	en
heal.journalName	Progress in Biomedical Optics and Imaging - Proceedings of SPIE	en
dc.identifier.doi	10.1117/12.647602	en
dc.identifier.volume	6094	en