what does it contain?
It is largely similar to blood plasma except that the Cerebrospinal fluid is nearly protein-free compared with plasma and has some different electrolyte levels. Chlorides, sodium, 0.3% plasma proteins, fewer than 5 white blood cells per mm³
Cerebrospinal fluid
CSF is derived from blood plasma and is largely similar to it, except that CSF is nearly protein-free compared with plasma and has some different electrolyte levels. Due to the way it is produced, CSF has a higher chloride level than plasma, and an equivalent sodium level.

CSF contains approximately 0.3% plasma proteins, or approximately 15 to 40 mg/dL, depending on sampling site. In general, globular proteins and albumin are in lower concentration in ventricular CSF compared to lumbar or cisternal fluid. This continuous flow into the venous system dilutes the concentration of larger, lipid-insoluble molecules penetrating the brain and CSF. CSF is normally free of red blood cells and at most contains fewer than 5 white blood cells per mm³ (if the cell count of the white blood cells is higher than this, it constitutes pleocytosis).
where is the cerebrospinal fluid that surrounds the spinal cord located It fills the central canal of the spinal cord. what is this fluid? It is a clear, colorless body fluid found in the brain and spinal cord.
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Cerebrospinal fluid [SEP] Contents
CSF is derived from blood plasma and is largely similar to it, except that CSF is nearly protein-free compared with plasma and has some different electrolyte levels. Due to the way it is produced, CSF has a higher chloride level than plasma, and an equivalent sodium level. CSF contains approximately 0.3% plasma proteins, or approximately 15 to 40 mg/dL, depending on sampling site. In general, globular proteins and albumin are in lower concentration in ventricular CSF compared to lumbar or cisternal fluid. This continuous flow into the venous system dilutes the concentration of larger, lipid-insoluble molecules penetrating the brain and CSF.