Hemastix
Definition
A commercial peroxidase test strip (Siemens/Bayer) containing a chromogenic pad that turns blue-green on contact with haemoglobin and hydrogen peroxide. Originally designed for clinical detection of blood in urine; adapted for forensic scene screening.
- Manufacturer
- Siemens/Bayer
- Type
- Peroxidase test strip
- Positive colour change
- Blue-green
- Original clinical use
- Blood detection in urine
- Forensic use
- Scene screening for blood
Common questions
Is a positive Hemastix result confirmatory for human blood at a scene?+
No, it is a presumptive test reacting to haemoglobin's peroxidase-like activity, and it also gives false positives with animal blood, plant peroxidases and some cleaning agents, so a positive result needs a confirmatory anti-human haemoglobin test.
How does Hemastix compare to Bluestar for scene screening?+
Hemastix is applied by direct contact with a suspected stain for a fast colour-change readout on the strip, while Bluestar is sprayed over larger areas and reveals latent blood by chemiluminescence in darkness, suiting different scale needs.
Related terms
- Bluestar
- A proprietary reformulation of luminol (brand name: Bluestar Forensic) that uses a modified buffer and reagent concentration to produce chemiluminescent detection of...
- Buffer System
- The pH-controlling salt mixture in a spray reagent. The buffer in Bluestar is designed to maintain an alkaline pH for the luminol...
- Chromogenic Pad
- The reactive zone on a Hemastix strip impregnated with a reduced chromogen (tetramethylbenzidine in some formulations) and a peroxide source. Contact with...
- Dipstick Test
- A format in which reagents are embedded in pads on a solid strip. The strip is briefly dipped into or pressed against...
- Haematuria
- The clinical term for blood in urine. Hemastix was developed as a urinalysis tool to detect haematuria and was later adopted by...