Glycated Serum Protein (GSP) LiquiColor® Assay


An introduction to Glycated Serum Protein

EKF Diagnostics’ Glycated Serum Protein (GSP) LiquiColor® Assay offers a two to three week indicator of average blood glucose. This closes the information gap between daily glucose levels and quarterly HbA1c testing.

EKF Diagnostics’ Glycated Serum Protein (GSP) LiquiColor® Assay offers a 2 – 3 week indicator of average blood glucose.

Glycated Serum Protein (GSP) serves as an accurate intermediate marker of glycemia in instances where HbA1c may be of limited value such as pregnancy, reduced RBC lifespan and hemodialysis.

The difference between actual measured HbA1c and predicted HbA1c from glycated serum protein is called the glycation gap.

Measuring HbA1c and Glycated Serum Protein (GSP) together offers improved diagnostic accuracy by more reliably predicting complications of diabetes including nephropathy and retinopathy.

Glycated Serum Protein (GSP) provides superior specificity and accuracy compared to fructosamine assays (NBT method) for monitoring and assessment of short-term to medium-term (past two to three week period) average blood glucose levels.

Complementary to HbA1c in diagnosis and screening of diabetes.

Studies suggest that combining Glycated Serum Protein (GSP) results with HbA1c measurements provides a better assessment of long term risk of diabetic complications.

Methodology Correlation to predicate method Linearity On-board stability* Calibration Sample type Sample size*
Enzymatic N = 65
R2 = 0.9966
Slope = 0.9542
Y intercept = 14.567
Range of values = 60-1249 µmol/L GSP
21.0 to 1354.0 µmol/L Four weeks at 2 – 8ºC Two point
Sold separately
Serum 10 µL

* Analyzer dependent

  Control level 1 Control level 2 Serum level 1 Serum level 2
N 80 80 80 80
Mean (µmol/L) 204 751 251 373
SD (µmol/L) 2.2 4.9 1.9 2.4
CV (%) 1.1% 0.7% 0.8% 0.6%
Control level 1 Control level 2 Serum level 1 Serum level 2
N 80 80 80 80
Mean (µmol/L) 204 751 251 373
SD (µmol/L) 2.4 5.6 3.2 3.7
CV (%) 1.2% 0.7% 1.3% 1.0%

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