Assay of gentamicin in cerebrospinal fluid.
A comparison of standard curves obtained from a conventional plate diffusion assay method revealed significant differences when gentamicin standards were made up in different media. Standards made up in distilled water resulted in a curve which differed from that of standards made up in pooled human cerebrospinal fluid by a factor of up to 4. When the assay medium was supplemented with 0-5% sodium chloride, the difference between the two standard curves was reduced to a factor of about 1-5. The curve obtained from standards made up in 150 mM sodium chloride/4-5 mM calcium chloride correlated well with that from standards made up in cerebrospinal fluid. There was no evidence of gentamicin being bound to protein in the cerebrospinal fluid.
D001681:Biological Assay / Q000379:methods*; D002122:Calcium Chloride; D003470:Culture Media; D004058:Diffusion; D005839:Gentamicins / Q000134:cerebrospinal fluid*; D006801:Humans; D007709:Klebsiella / Q000187:drug effects; D011869:Radioligand Assay; D012965:Sodium Chloride
D003470:Culture Media; D005839:Gentamicins; D012965:Sodium Chloride; D002122:Calcium Chloride