Skip to content

High-Performance Liquid Chromatography (HPLC) Measurement of Hemoglobin A1c (HbA1c) in Whole Blood

Published: August 9, 2026Updated: August 16, 2026

This test measures the percentage of hemoglobin that is coated with sugar (glycated hemoglobin), reflecting your average blood sugar levels over the past 2–3 months.

Quick summary

["Helps track long-term blood sugar control for diabetes management."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
94537-8
Short code
Hgb Pnl Bld HPLC
Synonyms
Hgb Pnl Bld HPLC
Category
hematology
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
12
Ref high
17.5
Critical range
7 N/A – 20 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
hplc
CPT
85018
SNOMED
900000000000003004
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Matters

HbA1c is a key marker for managing diabetes because it shows how well your blood sugar has been controlled over time. Unlike daily blood sugar checks, it provides a broader picture of your health.

How the Test Works

Blood is drawn and analyzed using high-performance liquid chromatography (HPLC), a precise method that separates and measures different types of hemoglobin, including the glycated form.

What to Expect Before the Test

No special preparation is needed, but you may want to check with your provider if you’re taking certain medications or have recent blood donations.

What the Results Mean

Results are expressed as a percentage and help your healthcare team assess whether your diabetes treatment plan is effective. Values are compared to clinical guidelines, not individual reference ranges.

Reference range

Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A

Specimen: serum

No special preparation required. Inform provider of any chest pain or symptoms.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

HbA1c by HPLC

Frequently asked questions

How often should I get this test?
Typically recommended every 3–6 months for people with diabetes to monitor progress and adjust treatment as needed.
Can fasting affect this test?
No, HbA1c reflects average blood sugar over time and is not affected by recent meals or fasting status.
What if my results are outside the normal range?
Your provider will discuss next steps, which may include retesting, reviewing your treatment plan, or exploring additional tests to identify underlying causes.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy