Crime Scene Investigation (CSI) requires technology for a rapid, non-destructive, and accurate detection of a wide variety of evidence including invisible stains of bodily fluids. Particularly crucial is the discrimination of semen in stained evidences from sexual assault cases as those evidences have high odds of containing aggressor DNA. AXO Science is now evaluating the feasibility of a new product: STK Spray. This product addresses Crime Scene Investigation (CSI) concerns following suspicion of sexual assault. STK Spray is a revealing biochemical reagent for semen stains mapping and will be part of the Crime Scene Technician (CST) tool box. It is a dissolving powder to produce a ready to use sprayable solution. After spraying the solution over suspected materials (fabrics, carpets, sofas, beddings, car seats, flooring, etc, comprising items that cannot be send to the laboratory) a portable UV lamp specifically reveals semen presence within 3 minutes. The CST is then able to sample the stains and send them for DNA profiling. Such technical product has no equivalent in helping scientific police to fight crime. Thanks to the Executive Agency for Small and Medium-sized Enterprises (EASME) the proof of concept of STK Spray which allows specific and sensitive detection of Prostatic Acid Phosphatase only contained in human male semen, allows direct sampling by swabbing evidence and does not affect DNA for amplification and profiling has been successfully achieved.  This project has received funding from the European Union’s Horizon 2020 SME-Instrument program under grant agreement No 815553.