In situ analysis of bacterial extracellular polymeric substances from a Pseudomonas fluorescens biofilm by combined vibrational and single molecule force spectroscopies.

Extracellular polymeric substances (EPS) play an important role in biofilm cohesion and adhesion to surfaces. EPS of a P. fluorescens biofilm were characterized through their vibrational spectra (infrared and Raman) and their conformational properties using single molecule force spectroscopy with specific probes for glucose, galactose, and N-acetyl glucosamine-rich EPS.

Hydration effects on the barrier function of stratum corneum lipids: Raman analysis of ceramides 2, III and 5.

The stratum corneum is the outermost layer of the skin; its barrier function is highly dependent on the composition and the structure as well as the organization of lipids in its extracellular matrix. Ceramides, free fatty acids and cholesterol represent the major lipid classes present in this matrix. They play an important role in maintaining the normal hydration levels required for the normal physiological function.