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Showing posts with the label Advantages of Gel-Clot Method

Gel- Clot Test

The Gel-Clot Test is the most widely recognized and traditional method used in Bacterial Endotoxin Testing (BET) endotoxins in pharmaceutical products, water for injection, and biologicals. The test is based on the gel formation reaction between Limulus Amebocyte Lysate (LAL) and bacterial endotoxin. 1. Principle of Gel-Clot Test The Gel-Clot Test relies on the natural defense mechanism of the horseshoe crab ( Limulus polyphemus ). The lysate prepared from the crab’s blood cells (amebocytes) contains enzymes that are activated in the presence of endotoxin (lipopolysaccharide, LPS) . When LAL reagent reacts with endotoxin, it triggers a cascade leading to clot (gel) formation. Principle Summary: Positive reaction: Firm gel formation indicates the presence of endotoxin at or above the test sensitivity (λ). Negative reaction: No gel formation (fluid remains liquid) indicates the absence of detectable endotoxin. This test provides a qualitative result — “Pres...
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