Page 30 - 00. Complete Version - Progress Report IPEN 2014-2016

30 Lasers Technology | Progress Report

Figure 11: The lesion progression of measured with OCT

secondary antibody, and finally washed again. and flexible. The laboratory has studied the
A colorimetric reaction is produced in the mi- improvement of optical setup itself and also
croreactor to indicate the presence of the an- new ways of data analysis, such work provid-
tibody. The use of the development kit whose ed interesting results in the period, and they
substrate is orthophenylenediamine showed are presented in the following paragraphs.
a color change from transparent to yellowish,
evidencing the success of the device produced. A non-invasive technique for glucose monitor-
Assays on plaques without the antigen were ing was developed in order to improve glucose
also made for the negative control. control and treatment in patients with diabe-
tes. Optical Coherence Tomography may offer
As a diagnostic tool another laser health appli- a good alternative for portable glucometers,
cation Optical coherence tomography (OCT) is since it uses light to probe samples. Changes
a diagnostic imaging technology based on low in the object of interest can alter the intensity
length coherence interferometry in which the of light returning from the sample and, eval-
coherence features of photons are explored, uating these changes, one can estimate the
leading to an imaging technology that is ca- sample’s attenuation coefficient (μt) of light.
pable of producing non-contact, non-destruc- We explored this behavior of μt for mouse’s
tive, high-resolution cross-sectional images of blood under increasing glucose concentrations.
internal microstructures of living tissues. We The system proved to be sensitive for all blood
implemented several OCT systems. glucose concentrations tested, with good cor-
relations with the obtained attenuation coef-
Innovative studies are being performed in or- ficients. A linear tendency was observed as a
der to make OCT a tool even (more) powerful function of increasing attenuation with high-

Instituto de Pesquisas Energéticas e Nucleares