Studies in difference spectra of cerebrospinal fluid.

Cerebrospinal fluids were treated with acid and the extent of protein denaturation along with surface perturbations was followed spectrophotometrically (method of difference spectra). It was found that the fluid samples from patients suffering from a number of neurologic diseases differed considerably among themselves and from pure proteins. The spectrophotometric differences obtained by the addition of a high concentration of acid (pH 1.2, final) were found to be enhanced when the spectra of the fluids at graded acid levels were compared. Cerebrospinal fluids could be divided into two groups based on their responses to smaller concentrations of acid (at pH levels of 7.0 and 4.0). Fluids from patients with multiple sclerosis were found in only one group.