[A modified microanthrone method for the determination of inulin on nanogram scale].
The establishment of a method of determining minute amount of inulin on nanogram scale is essential for applying micropuncture technique to kidney research. In this experiment, we modified a classical microanthrone method which was used by Dirks et al. to determine inulin contained in tubular fluid. A spectrophotometer was installed with a special microcuvette to suit the colorimetry of 10 microliters solution. Linear relation between inulin concentration and absorption was observed in the range of inulin concentration from 2 to 32 nl per 10 microliters anthrone reagent. The accuracy of this microanthrone method was evaluated with inulin recovery test, the mean recovery rate being 101.2 +/- 3.5%. Since tubular fluid did not interfere with the determination of inulin, the tubular fluid which contained inulin could be added directly to anthrone reagent in actual practice. The mean single nephron glomerular filtration rate measured with this modified microanthrone method in 21 rats was 34.9 +/- 1.8 nl/min, which coincided well with the values reported in literature. The results indicate that the measurement of inulin with the above-mentioned microanthrone method is reliable and suitable for the micropuncture study.
He
X R
XR
Department of Physiology, Shanghai Medical University.
Yao
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D000818:Animals; D000873:Anthracenes; D003124:Colorimetry / Q000379:methods; D005919:Glomerular Filtration Rate / Q000502:physiology; D007444:Inulin / Q000032:analysis*; D007668:Kidney / Q000502:physiology*; D008297:Male; D009399:Nephrons / Q000502:physiology*; D011677:Punctures; D051381:Rats; D011919:Rats, Inbred Strains; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D000095322:Anthrones
D000873:Anthracenes; D007444:Inulin; C004522:anthrone; D000095322:Anthrones