CARBON-DIOXIDE CLATHRATES - AN IR SPECTROSCOPIC MARKER FOR ARTHRITIS

The IR spectra of dry films of synovial fluid from normal and arthritic joints are presented. The spectra suggest the existence of CO2 clathrates in these fluids which are of remarkable stability in comparison to well-known CO2 clathrate hydrates. To our knowledge, this is the first demonstration of the formation of CO2 clathrates in biological media. The proportion of CO2 clathrates found in synovial fluid appears to vary with the state of health of joints and thus may be of use in the clinical diagnosis of arthritis.