Development of a spectrofluorometer with USB interface for in vivo measurements in surgical procedures

In this paper we present the development of a portable spectrofluorometer with USB interface for in vivo measurements in biological tissue. The equipment consists of a mini-spectrometer HR4000CG-UV-NIR, with a working range from 200 to 1100 nm with a resolution of 0.5 nm FWHM. As the excitation source a light emitting diode at 365 nm, with maximum radiant power of 200 mW was used. A bifurcated fiber optic (R200-UV/VIS) with six 200 µm diameter irradiation fibers and one 200 µm collection fiber is used. The system is powered and controlled with a laptop, avoiding the use of an external power supply. A program to select the light source, to process and measure spectra in real time was developed using the graphic language G of LabVIEW 8.2. Also, in this issue are presented in vivo measurements of diffuse reflection and fluorescence of non-neoplastic and neoplastic cerebral tissue of patients affected with glioblastoma multiform tumors (GBM).