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ELISPOT moderate

White Spots in Center of Normal Spots (Donut Pattern)

Symptom
Spots develop with white or lighter centers surrounded by darker rings, creating a donut-like appearance. This is more common with enzymatic detection methods.
Common Causes
  1. 1 Coating antibody concentration insufficient for optimal capture
  2. 2 Issues during the coating step affecting antibody distribution
  3. 3 For fluorescence detection: antibody concentrations too low
Solutions
  1. 1 Increase coating antibody concentration through optimization
  2. 2 Evaluate spot quality to determine if capture antibody dilution or coating step has issues
  3. 3 For fluorescence detection: increase antibody concentrations for both capture and detection
Related Video (2)
Mabtech ★ 85
ELISpot tutorial: step-by-step full assay protocol
"Step-by-step protocol video from a major ELISpot supplier likely shows correct antibody coating concentrations and troubleshooting tips for donut spot artifacts."
Animated biology With arpan ★ 70
Elispot assay ( assay to determine cytokine producing cells)
"General ELISpot assay demonstration helps contextualize how spots form and why detection artifacts like donut patterns occur."
Source: abcam.com ↗
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