Biomaterials Lab 3 PPT Fall 2024 PDF

Biomaterials - ENGR-UH 4810 Fall 2024 Professor: Jeremy Teo Instructor: Shafiya Sabah 1 Lab 3: Spectroscopy-based Characterization of Hydrogels...

Biomaterials - ENGR-UH 4810 Fall 2024 Professor: Jeremy Teo Instructor: Shafiya Sabah 1 Lab 3: Spectroscopy-based Characterization of Hydrogels 2  FTIR spectroscopy ▪ Infrared spectroscopy is the study of the interaction of infrared light with matter. 4000 𝑐𝑚−1 400 𝑐𝑚−1 3  FTIR Spectroscopy functional group correlation table 4  FTIR Spectroscopy ▪ The atoms in chemical compounds are constantly moving and vibrating. ▪ Each of these vibrations occurs at a specific frequency unique to the chemical bond and molecular structure. ▪ When the frequency of IR light matches one of these vibrational frequencies, the compound absorbs the IR light, which excites these vibrations within the molecules. ▪ After the IR light passes through the sample and is detected, we can plot the information obtained to create an IR spectrum. ▪ The signal must first be Fourier-Transformed (FT) to produce the intensity as a function of wavenumber. 5  FTIR Spectroscopy Watch Video: https://www.youtube.com/watch?v=0e_xBwQ7znI&t=83s 6  ATR FTIR Spectroscopy ✓ Light appears to travel in a beam, it actually travels like a wave and waves tend to spread out a little bit in space. ✓ This means that although the light traveling through the Attenuated Total Reflectance crystal is internally reflected, some of the light can slightly Enables samples to be examined penetrate the sample. directly in the solid or liquid state without further preparation. ✓ This light that interacts with the sample is often referred to as an evanescent wave. Penetration depth = 0.5-2 μm ✓ The intensity of this field decays rapidly. ✓ IR light only interacts with the first few microns of the sample, allowing us to get an ATR FT-IR spectrum. 7  ATR FTIR Spectroscopy Watch Video: https://www.youtube.com/watch?v=QW2uh1BQuGw 8  Chemical structure of Agarose and Collagen Agarose Collagen 9