Analysis of Cerebrospinal Fluid for Proteins
and Sugars^34
34.1 Theory
Cerebrospinalfluid (CSF) is a clear and colorlessfluid that occurs between the layers
pia mater and arachnoid mater covering central nervous system. CSF is formed by
secretory activities of the choroid plexus, the vascular structure lying within the
ventricles of brain. CSF primarily acts as a water shock absorber and also acts as a
carrier of nutrients and waste products between the blood and the central nervous
system. The volume of CSF formed is about 100–250 ml in adults in 24 h. The
composition of CSF is same to that of brain extracellularfluid. The ionic composi-
tion for CSF is similar to the plasma for some components but differ for many other
substances. Generally the composition of sodium, chloride, and magnesium in CSF
is same or greater than serum, but potassium, calcium, and glucose are lower than
serum. CSF glucose concentration is 60% of serum.
Note After drawing the CSF sample, the analysis of glucose and proteins should be
carried out immediately. Otherwise, the specimen must be stored at 20 C which is
stable for 3 days. Glucose will be rapidly destroyed in the absence of preservatives.
34.2 Analysis of Proteins in CSF
34.2.1 Pyrogallol Dye-Binding Method
34.2.1.1 Principle
Protein molecules present in CSF bind quantitatively with pyrogallol red-molybdate
complex at pH 2.0 to form a violet-colored complex, which is measured at 600 nm.
34.2.1.2 Reagents
1.Pyrogallol red dye: To prepare the dye, dissolve 10 mg disodium molybdate,
134 mg sodium oxalate, 5.9 g succinic acid, and 430 mg sodium benzoate in
#Springer Nature Singapore Pte Ltd. 2018
V. Kumar, K. D. Gill,Basic Concepts in Clinical Biochemistry: A Practical Guide,
https://doi.org/10.1007/978-981-10-8186-6_34
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