Dipsticks for testing for the presence of a target nucleic acid in a sample solution are described the dipsticks comprise a universal capture probe immobilised at a capture zone of the dipstick. The universal capture probe is capable of hybridising to a hook capture probe which is hybridised to the target nucleic acid in the sample solution. A contact end of the dipstick is contacted with the sample solution to cause hook capture probe hybridised to the target nucleic acid to move by capillary action to the capture zone where the target nucleic acid can be detected. Use of the universal and hook capture probes allows dipsticks to be prepared which can be used to capture any target nucleic acid, thereby simplifying preparation of the dipsticks. Specificity of target nucleic acid capture is then achieved by use of an appropriate hook capture probe. Methods and kits are also described.