Strong light scattering and absorption limit visualization of the internal structure of biological tissue. Only special tools
for turbid media imaging, such as optical diffuse tomography, enable noninvasive investigation of the internal biological
tissues, including visualization and intravital monitoring of deep tumors.
In this work the preliminary results of fluorescence diffuse tomography (FDT) of small animals are presented. Using of
exogenous fluorophores, targeted specifically at tumor cells, and fluorescent proteins expressed endogenously can
significantly increase the contrast of obtained images. Fluorescent compounds of different nature, such as sulphonated
aluminium phthalocyanine (Photosens), red fluorescing proteins and CdTe/CdSe-core/shell nanocrystals (quantum dots)
were applied. The animal was scanned in the transilluminative configuration by low-frequency modulated light (1 kHz)
from Nd:YAG laser with second harmonic generation at the wavelength of 532 nm or semiconductor laser at the
wavelength of 655 nm. Photosens was injected intravenously into linear mice with metastazing Lewis lung carcinoma in
dose 4 mg/kg. Quantum dots (5x10-11 M) or protein DsRed2 (1-5x10-6 M) in glass capsules (inner diameter 2-3 mm)
were placed inside the esophagus of 7-day-old hairless rats (18-20 g) to simulate marked tumors. Cells of HEK-293
Phoenix line, transitory transfected with Turbo-RFP protein gene, were injected hypodermically to immunodeficient
This work demonstrates potential capabilities of FDT method for detection and monitoring of deep fluorescent-labeled
tumors in animal models. Strong advantages of fluorescent proteins and quantum dots over the traditional photosensitizer
for FDT imaging are shown.