Label-Free Single and Multi-Photon Fluorescence Spectroscopy to Detect Brain Disorders and Diseases: Alzheimer, Parkinson, and Autism From Brain Tissue, Cells, Spinal Fluid, and Body Fluids
A label free single or multi-photon optical excitation fluorescence spectroscopy for measuring the differences between the levels of fluorophores from tryptophan, collagen, reduced nicotinamide adenine dinucleotide (NADH), and flavins exist in brain samples from a of Alzheimer's disease (AD) and in normal (N) brain samples with label-free fluorescence spectroscopy. Relative quantities of these molecules are shown by the spectral profiles of the AD and N brain samples at excitation wavelengths and multi photons about 266 nm, 300 nm, 400 nm and 500 nm. The emission spectral profile levels of tryptophan and flavin were much higher in AD samples, while collagen emission levels were slightly lower and NADH levels were much lower in AD samples. These results yield a new optical method for detection of biochemical differences in animals and humans for Alzheimer's disease. These molecules in AD and N tissues and cells can be excited by 1PEF, 2PEF, 3PEF, 4 PEF using fs and ps pulses
