A blood sugar test is a procedure that measures the amount of sugar, or glucose, in your blood. Your doctor may order this test to help diagnose diabetes.
Also Known as: Fasting Blood Sugar, FBS, Fasting Blood Glucose, Blood Sugar Fasting, BSF, BSL
Test Panel: Blood Sugar, Fasting Blood Sugar, FBS, Fasting Blood Glucose, FBG, Fasting Plasma Glucose, FPG, Blood Glucose, Oral Glucose Tolerance Test, OGTT, GTT, Urine Glucose

Principle:
Glucose is oxidised to gluconic acid and hydrogen peroxide in the presence of glucose oxidase. Hydrogen peroxide further reacts with phenol and 4 – aminoantipyrine by the catalytic action of peroxidase to form a red coloured quinoneimine dye complex. Intensity of the colour formed is directly proportional to the amount of glucose present in the sample.

Normal Values:
- Fasting Blood Sugar: 74 to 106 mg/dL (4.5 to 5.9 mmol/L)
- Random Blood Sugar: 80 to 120 mg/dl (4.4 to 6.6 mmol/L).
Kit Content:
L1 : Glucose Reagent | 2 x 150 ml, 3 x 150 ml, 1 x 1000 ml |
S : Glucose Standard (100 mg/di) | 5.0 ml |
Reagent Storage I stability
Contents are stable at 2-8°C till the expiry mentioned on the labels. Upon storage the Glucose reagent may develop a slight pink colour. This does not affect the performance of the test.
Reagent Preparation:
Reagents are ready to use.
Sample Required:
Serum, plasma, CSF. Glucose is reported to be stable in the sample for 7 days when stored at 2-8°C.
System Parameters:
Reaction | End Point |
Wavelength / filter | 505 nm (Hg 546 nm)/ Green |
Zero Setting | Reagent Blank |
lncub. Temperature | 37°C / R. T. |
lncub. Time | 10 min. / 30 min. |
Light path | 1cm |
Delay Time | |
Read Time | |
No. of read. | |
Interval | |
Volume | 400 μL |
Standard | 100 mg/di |
Factor | |
React. Slope | Increasing |
Linearity | 500 mg/dl |
Units | mg/dl |
Procedure:
Pipette into clean dry test tubes labelled as Blank (B), Standard (S), and Test (T):
Additiion Sequence | B (Blank) | S (Standard) | T (Test) |
---|---|---|---|
Glucose Reagent (L1) | 1000 μL | 1000 μL | 1000 μL |
Distilled water | 010 μL | ||
Glucose Standard (S) | 10 μL | ||
Sample | 10 μL |
Mix well and incubate at 37°C for 10 min. or at R.T. (25°C) for 30 min. Measure the absorbance of the Standard (Abs.S), and Test Sample (Abs.T) against the Blank, within 60 Min.
Test Calculation:

Linearity:
This procedure is linear upto 500 mg/di. If values exceed this limit, dilute the serum with normal saline (NaCl 0.9%) and repeat the assay. Calculate the value using the proper dilution factor.
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