Skip to main content
  • Oral presentation
  • Open access
  • Published:

Fluorescence kinetics of Foscan, Fospeg and Foslip in the window-chamber model


Foslip and Fospeg are new formulations of the photosensitzer m-THPC, intended for use in Photodynamic Therapy (PDT) of malignancies. Foslip is m-THPC bound to conventional liposomes, Fospeg consists of m-THPC bound to pegylated liposomes. Possible differences in tumour-fluorescence and vasculature kinetics between Foslip, Fospeg and Foscan were studied using the rat window-chamber model.

Materials and methods

In 18 rats a dorsal skinfold window-chamber was installed and a mammary carcinoma was transplanted in the subcutaneous tissue. The dosage used for intravenous injection was 0.15 mg of m-THPC for each formulation. At 7 time-points after injection (5 minutes – 96 hours), mTHPC-fluoresence at its absorption-peak and auto-fluorescence were detected with a CCD. After correction, m-THPC fluorescence images were achieved. Fluorescence intensities of 3 different regions of interest (ROI) were assessed; tumour-tissue, vasculature and surrounding connective tissue.


Shortly after injection vascular m-THPC fluorescence was high for Foscan and Fospeg but not for Foslip. The latter showed a gradual increase in fluorescence. All photosensitizers showed different fluorescence intensity curves in time. Fospeg had higher m-THPC fluorescence in tumour tissue (p < 0.05) between 2 and 8 hours and showed this trend at later time-points compared to the other photosensitizers. Maximum tumour fluorescence is reached at 48 hours for Foslip and 24 hours for Foscan and Fospeg. No photosensitizer showed a significant difference between the tumour and surrounding tissue fluorescence.


There are differences in fluorescence intensities of Fospeg, Foslip and Foscan at all time-points. Pegylated liposomes showed higher uptake in tumour. No photosensitizer showed tumour-selectivity.

Author information

Authors and Affiliations


Rights and permissions

Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution License ( ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

De Visscher, S., Robinson, D.J., Kaščáková, S. et al. Fluorescence kinetics of Foscan, Fospeg and Foslip in the window-chamber model. Head Neck Oncol 1 (Suppl 1), O18 (2009).

Download citation

  • Published:

  • DOI: