The aim of this study is to use the Resonance Raman (RR) and fluorescence spectroscopic technique for tumor margin detection with high accuracy based on native molecular fingerprints of breast and gastrointestinal (GI) tissues. This tumor margins detection method utilizes advantages of RR spectroscopic technique in situ and in real-time to diagnose tumor changes providing powerful tools for clinical guiding intraoperative margin assessments and postoperative treatments. The tumor margin detection procedures by RR spectroscopy were taken by scanning lesion from center or around tumor region in ex-vivo to find the changes in cancerous tissues with the rim of normal tissues using the native molecular fingerprints. The specimens used to analyze tumor margins include breast and GI carcinoma and normal tissues. The sharp margin of the tumor was found by the changes of RR spectral peaks within 2 mm distance. The result was verified using fluorescence spectra with 300 nm, 320 nm and 340 nm excitation, in a typical specimen of gastric cancerous tissue within a positive margin in comparison with normal gastric tissues. This study demonstrates the potential of RR and fluorescence spectroscopy as new approaches with labeling free to determine the intraoperative margin assessment.
The dynamic theoretical model of photochemical and hologram formation in holographic photopolymer is established, and the dynamic development process of holographic storage in the photopolymer is discussed with the model. A holographic photopolymer sensitized by erythrosine B is prepared, which is composed of acrylamide as monomer, ployvinylalcohol as binder, triethanolamine as initiator. The influence of the exposure intensity on holographic storage characteristics is analyzed. The experimental data of transmittance and diffraction efficiency of the fabricated photopolymer with different exposure intensities are obtained. By means of fitting the experimental data of transmittance and diffraction efficiency as a function of time with five exposure intensities at a wavelength of 514nm, the variation of photochemistry and photopolymerization diffusion dynamic parameters such as the molar-absorption coefficient ε, quantum yield Φ, photobleaching coefficient <i>k<sub>p</sub></i>, polymerization rate <i>k<sub>0</sub></i> and diffusion time constant τ<sub>D</sub> is presented. The research results show that as the exposure intensity increases, so do also ε, <i>k<sub>p</sub></i> and <i>k<sub>0</sub></i>, but Φ becomes smaller. And τ<sub>D</sub> has no obvious changes except the sample is overexposed. This material has the characteristics of longer diffusion times for the monomer to travel from the unexposed to the exposed zones than that in the case of other polymeric materials.
In this thesis, two kinds of photopolymer films sensitized by azure I and azure II respectively are fabricated and their important holographic characteristics including the sensitive spectral range of films, transmittance, diffraction efficiency (DE), the thickness of photopolymer films and refractive index modulation are compared. It can be found that the photopolymer film sensitized by azure II(sample 2) has more obvious advantages than the photopolymer film sensitized by azure I (sample 1)on the holographic characteristics from the absorption intensity and the optimum concentration of dye and the inner uniformity of sample to the photochemical reaction velocity and the optimum medium thickness. On the contrary, sample 1 has higher maximum diffraction efficiency and refractive index modulation than sample 2.