Product Description
Restricted sale – For forensic use only
This product is sold only to professional forensic and institutional customers, such as forensic and crime laboratories, law enforcement agencies, prosecutors’ offices and medical examiners, hospitals and sexual assault (SANE/SAFE) programs, and universities or accredited research and training institutions. It is not intended for personal or household use. Pro Lab Supply may verify the buyer’s institution and credentials before shipping and may cancel orders that do not meet these requirements.
What is STK Skin?
Following a rape, purpose of victim forensic examination is first of all to identify and treat injuries, but the objective is also to help the investigation by attempting to collect assaulter’s semen traces.
Unfortunately, due to poor available solutions to locate sperm stains, current protocol relies mainly on blind swabbing, hoping to collect assaulter’s semen.
In order to deal with this issue, AXO Science has developed STK Skin, a sprayable solution that allows to specifically detect semen on victim’s skin and hair. Non-toxic, reliable and specific, STK Skin is the essential solution for forensic experts.
STK Skin is a presumptive test for the detection of human male semen on skin and hair, based on the specific detection of human acid phosphatase in seminal fluid. A positive result appears as a blue fluorescent signal under a 365 nm UV light with visible light filter, helping forensic examiners target swabbing instead of relying on blind swabbing. It is a non-toxic alternative to traditional acid phosphatase (AP) tests and to alternate light source (ALS) screening alone. STK Skin is for forensic use only and is not an IVD diagnostic product.
Key features
- Sprayable on the victim’s body and hair; non-toxic (protect eyes and mucosa).
- Does not damage DNA; fully compatible with extraction techniques.
- 1 pouch is enough to screen one person.
- According to AXO Science, semen traces remain detectable at least 24 hours post-assault, even after showering, and the test is effective on different skin tones, on cadaveric skin, and on natural, colored and bleached hair.
Specifications
| Catalog number | AXO-STK-SK-10 |
|---|---|
| Contents | 1 box of 10 individual STK Skin pouches |
| Use per pouch | 1 pouch is enough to screen one person |
| Preparation | 1 pouch dissolved in 100 ml (~3 US fl oz) of demineralized water; ready to use after 30 seconds |
| Read time | 10 seconds to 2 minutes after spraying |
| Reading | 365 nm UV light with visible light filter (e.g., STK UV Light or STK UV Light Mini), about 25 cm (~10 in) from the skin. Positive result: blue fluorescent signal |
| Prepared solution | Use within 24 hours; protect from sunlight. Do not keep or reuse an opened pouch |
| Shelf life | 2 years following production |
| Storage | Keep away from light and heat, below +35°C (+95°F) |
| Standards | ISO 18385 forensic grade. Batch number, produced according to ISO 13485 standards |
| Intended use | Presumptive test for human male semen on skin and hair. Not an IVD diagnostic product. For forensic use only |
How to use STK Skin?
Screen the victim with the UV light first, to see what reacts to the UV light on its own and be able to distinguish it from the STK Skin signal.
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1 Dilute 1 sachet of STK Skin in 100 ml (~3 US fl oz) of demineralized water
2 Spray victim’s body at a distance of ~20 cm (~8 inches)
3 Read results with a 365 nm UV light with visible light filter: only semen stains will glow in a blue color
Always run a positive control (STK Positive Control) with each analysis to validate the reagent and your UV light.
Frequently Asked Questions
Is STK Skin toxic?
STK Skin is not toxic and can be sprayed on victim’s body and hair. Protect victim’s eyes and mucosa.
Is STK Skin damaging DNA?
No, STK Skin is not damaging DNA and is fully compatible with extraction techniques.
How long can I use the STK Skin solution once diluted in water?
24h, protect it from sunlight.
Can I use any sprayer?
You can use any sprayer that produces a fine mist and avoids big drops of water.
Can I use any UV light?
No, you have to use a 365 nm UV light with visible light filter. Not every 365 nm UV light gives great results; please use a positive control to validate your UV light. We can recommend some specific 365 nm UV lamps if needed.
