Iron quantification in cerebrospinal fluid

Several studies have attempted to measure iron levels in cerebrospinal flui d (CSF), which is believed to contain very low levels of iron. In general, the assays used in these studies suffered from poor reproducibility or lack of sensitivity. In the present study, an assay was developed that enables iron quantitation in CSF using 150 mu l of undiluted CSF, sample digestion, dot blotting, Perls' histochemistry, 3,3'-diaminobenzidine enhancement, an d densitometry. Inter- and intraassay variability was low and sensitivity h igh (279 pg iron in 100 Ed). There were negligible readings for standard cu rves utilizing copper in place of iron. The iron content in eight normal CS F samples was 61.01 +/- 18.3 (SD) mu g/liter, and in nine normal sera it wa s 1332.7 +/- 408.2 (SD) mu g/liter. The present assay enables reliable meas ures of iron levels in biological samples. This assay should enable future studies that address how CSF iron levels change during the course Of variou s disease states. (C) 1998 Academic Press.