Lancashire Partnership Against Crime (LANPAC) is funding the use of SelectaDNA intruder spray on doors and windows in small stores.
The solution contains a UV tracer and a unique DNA code that marks skin, hair and clothing of offenders. The manufacturer says that although invisible and harmless, the UV and DNA will remain on an offender for weeks, in fibres of clothing and creases of the skin.
Forensic analysis can then prove that they have broken into a particular premises.
Warning signs and window stickers are supplied to alert potential criminals that the system is in use. A LANPAC spokesman said: "If the worst happens and a robber does enter a premises by force, they will be sprayed with the DNA which links them instantly to the crime scene. However, it is likely that they would flee with no gain as soon as they are sprayed, as the DNA fear-factor among criminals is high."