Table 1 Comparison of different methods measuring the concentrations of glucose and asparagine in different biological samples

From: Direct electrical quantification of glucose and asparagine from bodily fluids using nanopores

 

Glucose

Asparagine

Nanopore

Sampled volume

Commercial assay

Nanopore

Sampled volume

LC assay

Sweat

105 ± 9 µM

2 µL

105 ± 7 µM

94.6 ± 5.0 µM

5 µL

90.9 ± 4.1 µM

Urine

368 ± 7.5 µM

200 nL

381 ± 6 µM

35.4 ± 2.8 µM

4 µL

89.7 ± 3.6 µM

Saliva

5.71 ± 0.48 µM

15 µL

10.4 ± 7.9 µM

1.36 ± 0.22 µM

30 µL

ND

Blood sample 1

5.09 ± 0.88 mM

10 nL

5.3 mM

10.2 ± 0.2 µMa

5–15 µL

6.7 ± 0.2 µMa

Blood sample 2

4.91 mM

10 nL

4.9 mM

   

Blood sample 3

4.21 mM

10 nL

4.4 mM

   
  1. The concentration of glucose was measured using a glucose (HK) assay kit (Sigma-Aldrich) except for blood samples, where an Accu-Chek® Aviva (Roche) system was used. Since the latter system did not provide an error in the measurement, three different blood samples were tested. The concentration of asparagine was measured using a HPLC assay coupled with fluorescence detection. Sweat and urine were directly sampled, while the proteins in saliva and serum were precipitated with 8% trichloroaceticacid prior the HPLC measurements. The concentration of asparagine in saliva was too low to be measured with the HPLC assay
  2. aSince a pre-purification step was required for LC sampling, serum instead of blood was used for the quantification of asparagine. Error is SD