The present invention provides synthetic DNA aptamers that bind a target explosive to allow detection of that explosive. In various embodiments, the synthetic DNA aptamers may include one or more aptamers selected from the group consisting of SEQ ID 1-6. The various synthetic DNA aptamers are sensitive to different explosives. The synthetic DNA aptamers provide an inexpensive, in situ means for testing for explosive, which may be used for both soil and water samples. This testing may include an assay method using the synthetic DNA aptamers or a biosensor linked to the synthetic DNA aptamers.