Buffer System
Definition
The pH-controlling salt mixture in a spray reagent. The buffer in Bluestar is designed to maintain an alkaline pH for the luminol reaction while minimising acid hydrolysis and oxidative attack on the DNA phosphodiester backbone.
- Function
- pH control in a spray reagent
- Example
- Bluestar's alkaline buffer
- Purpose
- Sustain the luminol reaction
- Secondary effect
- Limits DNA hydrolysis, oxidation
- Field
- Bloodstain enhancement chemistry
Common questions
Why does the pH of the buffer matter for luminol-based reagents?+
The luminol chemiluminescent reaction needs an alkaline environment to proceed efficiently, so the buffer holds the working solution at the pH required for a strong, consistent glow on contact with blood.
Does the buffer system affect later DNA recovery from the stain?+
A well-formulated buffer is designed to minimise the acidic hydrolysis and oxidative attack that can degrade DNA, which is why some formulations are marketed as more DNA-friendly than older luminol recipes.
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