What is Sperm Tracker ?

Rape is a global scourge. It is estimated that 1 woman out of 5 will face rape or attempted rape in her lifetime. Hidden truth lies in millions of unsolved rapes that cannot be proven in the absence of evidence found, sperm traces in front. According to RAINN, out of 1000 sexual assaults, only 4.6 rapists will go to jail.

Crime Scene and Crime Laboratory Technicians often face the difficult task to locate semen traces on evidences and on the scene within a short period of time.

If alternate light sources are widely used, scientific literature agrees that they are unspecific (false positives) and insensitive (false negatives).

It is sometimes estimated that 30% of semen stains are missed by alternate light sources available on the market. Acid Phosphatase spot tests, if more sensitive and specific, are using carcinogen reagent for the user, are long to perform, require lab-prepared mixtures and often lead to repositioning issue and wrong sampling.

After years of research in collaboration with the French Scientific Police (SNPS), AXO Science is now bringing to the forensic experts the Sperm Tracker Technology that improves both sensitivity and specificity of semen detection and offers many advantages to crime laboratory experts and CSI for detecting semen stains.


Learn more about STK technology

Two products for Total Scene Screening

Screen the rape scene

STK Spray disrupts current procedures by instantly & reliably detecting semen traces directly on the scene.

We empower Police forces by bringing this new tool to the very hands of Crime Technicians, on site and allow a complete screening of a rape case.

Stop wasting time with tons of false positives and never leave a crucial evidence behind again.

Screen clothes in the lab

Mapping technics often use toxic reagents that are then time consuming and dangerous to use both for DNA and the operator.

Alternate Light Sources are known for generating lots of false positives and also...false negatives.

STK Lab is ready to use, non-toxic, highly sensitive and specific to semen.

One solution to screen victim's body and hair

STK Skin

Screen victim's body and hair

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.

Recent news

[STK Sperm Tracker Workshop] - Special thank you to all international attendees and speakers for their active participation to the workshop. Thank you #GendarmeriePJGN & #IRCGN for hosting the event! Video may be online soon. Stay tuned. --> sperm-tracker.com pic.twitter.com/JBfBBVDco4

Merci à Sébastien AGUILAR pour son intervention sur le plateau de BFMTV. Nous saluons aussi le travail exceptionnel de la Police Scientifique et de la Gendarmerie Criminelle qui œuvrent au quotidien pour retrouver les suspects. #SpermTracker #tracesdesperme #viol #forensics pic.twitter.com/IlTy2Jdl2a

Many thanks to the @SUForensics for its outstanding work as part of the #NEAFS congress Your posters and presentation highlight perfectly STK Lab & STK Spray specificity and efficiency. Well done! #forensicuniversity #STKSpermTracker #forensic #police #semendetection #dna pic.twitter.com/WHq5zTEWTo

STK Skin & STK Spray demonstrations carried out by #Forenseek in Ivory Coast. More info: sperm-tracker.com #forensic #police #CSI #dna #sexualassault #rape #semendetection pic.twitter.com/x0nluU8Wb0

[STK Spray - COLD CASE]- Reno Police Department found semen traces on a 4 to 8 years old sexual assault scene that led to identify and arrest alleged assailant. We are glad STK Spray could spot semen traces that were not initially visible Congratulations to Reno PD on this case! pic.twitter.com/7jT71bip4o

We are attending the @ascld_ symposium in Reno You're welcome to stop by our booth 51 to discover the STK Sperm Tracker solutions sperm-tracker.com #ASCLD2022 #forensics #lab #crimescene #police #DNA pic.twitter.com/Dr75YdF1iv

[Semen screening workshop] Thanks to @SyracuseUniversity for its warm welcome! Erie County Monroe County Onondaga County #crimelabs also took part in this meeting, thanks for your attendance! #forensics #crimelabs #CSI #Police #DNA #sexualassault pic.twitter.com/89hj13mpNl

They trust us

The initial trial of using STK Spray went well. Seminal fluid fluoresced as expected.

Health Science Authority (Singapore)

Tested in parallel with Crimescope (CSS filter and orange and red glasses) STK Sperm Tracker clearly showed its ability to overcome fabric constraints (improved sensitivity) and to carry out two operations in one: both pinpoint stains and reveal their acid phosphatase activity. More reliable, faster and easier to set than the method currently in force within the INPS, STK Sperm Tracker represents a real step forward in the forensic field.

Emilie B. & Céline P. – Forensic Identification Specialists SNPS – LPS69 (France)

Both the STK Lab and Spray worked very well. I tested the products on undilute semen stains on a laminate tile and two dark polyester fabrics. The fluorescence was quickly and clearly visible.

Sam - Houston State University (USA)

Both the STK Lab and Spray worked very well. I tested the products on undilute semen stains on a laminate tile and two dark polyester fabrics. The fluorescence was quickly and clearly visible.

Sam - Houston State University (USA)

Results are very promising, sperm dog to locate the area and STK Spray to find the sperm traces in the last square meter, it looks like a very efficient team work.

Aki Salonen - Central Police Dept, Crime Scene Investigation Unit, Tampere (Finland)