The present invention provides methods and apparatus for measuring a property of an sample, the apparatus can manipulate, detect, and analyze the sample composed of single molecules, single small particles or single small samples of matter by drawing the sample into a nanofluidic channel and stretching the sample within the channel, passing the stretched sample through a gap having a width of less than or equal to 20 nm of a nanogap detector positioned inside or adjacent to the nanofluidic channel and measuring an output from the nanogap detector representative of the property of the sample.