Gel-Clot Endotoxin Testing (BET)
The gel‑clot assay is a simple, qualitative method designed for small‑scale, low‑volume endotoxin testing. The reagent is pre‑buffered to enhance resistance to sample interference. Single tests are ideal for routine endotoxin detection in research samples, offering a convenient, self‑contained solution for laboratories with limited testing needs.
For higher testing demands, multi-test formats are available and are well suited for laboratories performing frequent or batch endotoxin testing. These kits provide consistent performance across multiple assays, improve testing efficiency, and help reduce cost per test while maintaining the same reliability and ease of use as single-test formats.
BIOENTAL applies the Gel-Clot method for bacterial endotoxin (pyrogen) detection as a reliable and well-established testing approach used across the pharmaceutical and medical device industries.
The gel-clot method is valued for its simplicity, robustness, and regulatory acceptance. This method does not rely on instrumentation. Test results are determined by a clear physical outcome, the formation or absence of a firm gel making interpretation straightforward and dependable.
Attribute
Product Format
Sensitivity Range (EU/ml)
Catalog Numbers
Volume / Vial
Tests / Vial
Vials / Pack
Total Tests / Kit
LAL Content
CSE Included
Water for BET
Best Use Case
Single test vial
0.03 / 0.06 / 0.125 / 0.25 / 0.5
G020XXX
0.2 mL
1
50
50
Included
Not included
Not included
Fast single tests
Multi‑test vial
0.03 / 0.06 / 0.125 / 0.25 / 0.5
GC08170XXX
1.7 mL
16
8
128
8 LAL vials
4 × CSE 10 V (10 V = 1 - 199 EU)
2 × 50 ml
Small‑scale labs
Multi‑test vial
0.03 / 0.06 / 0.125 / 0.25 / 0.5
GC08520XXX
5.2 mL
50
8
400
8 LAL vials
4 × CSE 10 V (10 V = 1 - 199 EU)
2 × 50 ml
Medium‑scale labs
Multi‑test vial
0.03 / 0.06 / 0.125 / 0.25 / 0.5
GC100170XXX
1.7 mL
16
100
1600
100 LAL vials
10 × CSE 10 V (10 V = 1 - 199 EU)
Not included
GMP / regulated testing
Multi‑test vial
0.03 / 0.06 / 0.125 / 0.25 / 0.5
GC100170XXX
5.2 mL
50
90
4500
90 LAL vials
20 × CSE 10 V (10 V = 1 - 199 EU)
Not included
High‑throughput QC labs
What Is the Gel Clot Testing Method?
The gel clot endotoxin test is a qualitative method used to detect the presence of bacterial endotoxins. When a test sample is mixed with amebocyte lysate reagent and incubated under controlled conditions, the formation of a firm gel indicates the presence of endotoxin above the specified sensitivity limit. If a stable clot remains intact after gentle inversion of the tube, the result is considered positive. If no clot forms, the sample is negative at the tested sensitivity.
How the Gel Clot Method Works
The gel clot assay is the original bacterial endotoxin testing method and provides a clear yes‑or‑no result. Because it is an endpoint assay, it is especially useful for samples that may interfere with photometric or kinetic measurements. The method relies on visual observation rather than instrument‑generated readings, making it a straightforward and reliable option for many laboratory applications.
When Is Gel Clot Testing Suitable?
The gel clot method is commonly used when testing samples that:
- Are highly viscous
- Have strong or dark coloration (e.g. red, orange, yellow)
- Contain particulates, precipitates, or proteins (including trypsin)
- Interfere with chromogenic or turbidimetric detection
- Can cleave chromogenic substrates such as pNA
Required Equipment
The gel clot endotoxin test does not require complex instrumentation. A controlled heat source is sufficient for incubation, along with standard laboratory consumables.
Typical equipment includes:
- Dry heat block or water bath
- Reaction tubes or dilution tubes
- Micropipettes and pipette tips
- Timer and tube rack
Compendial Status
The gel clot endotoxin test is recognized as a compendial method in major pharmacopeias, including USP <85> and Ph. Eur. <2.6.14>, for bacterial endotoxin testing.
It is commonly used in regulated environments when qualitative results are acceptable.
Advantages and Limitations
Advantages and Limitations
Pharmaceutical manufacturing and quality control
Contract testing and microbiology laboratories
Water and raw material testing applications
Medical device manufacturers
Dialysis and healthcare‑related testing laboratories
Need Help Choosing the Right Gel Clot Solution?
Our team can help you select the appropriate product format and sensitivity based on your application.
