Skip to main content

SOP

Blood Glucose Testing (Fasting/Random)

SOP for quantitative measurement of glucose in serum or plasma.

Last verified 1 month ago 1 min read Clinical Chemistry Metabolic Endocrinology #diabetes #glucose #blood sugar #clinical chemistry #hexokinase
Link copied!
Document Control
Version
1.0
Effective
Aug 29, 2026
Reviewed
Aug 29, 2026
Department
Clinical Chemistry
Principle

Hexokinase (Reference): Glucose + ATP → Glucose-6-phosphate (via hexokinase). G-6-P + NADP+ → 6-phosphogluconate + NADPH (via G6PD). NADPH absorbance at 340 nm is proportional to glucose.

Standard Operating Procedure: Blood Glucose

1. Purpose: Diagnose and monitor diabetes mellitus and hypoglycemia.

2. Specimen: Serum, plasma (fluoride/oxalate preferred to inhibit glycolysis), or whole blood.

3. Reagents: GOD-POD (Glucose Oxidase-Peroxidase) or Hexokinase reagent kits.

4. Procedure (Automated Analyzer):

  • Load reagents and calibrators.
  • Aspirate sample and reagent in specified ratio (e.g., 1:100).
  • Incubate at 37°C.
  • Measure absorbance change at 505 nm (GOD-POD) or 340 nm (Hexokinase).

5. Reference Ranges

  • The canonical adult fasting reference interval is shown in the Reference Ranges panel below.

Decision Limits

  • Random glucose: Typically < 140 mg/dL (7.8 mmol/L).

6. QC: Run 2 levels of control daily.

Reference Ranges

Browse all ranges

70–99 mg/dL

Critical values apply

Frequently Asked Questions

Sodium fluoride inhibits enolase, preventing glycolysis and falsely low glucose results if testing is delayed.