The present invention is directed to an integrated microsystem and method for detecting biomolecules in a liquid sample. The integrated microsystem is made up of a sensor that includes microelectrodes connected to a matrix of carbon nanotubes deposited on a substrate, a micropump, a microcontroller for regulating the sample delivery, a signal processor for analyzing the sensor signal, a microheater that surrounds the carbon nanotube sensor, and microfluidic channel formed by a polydimethylsiloxane (PDMS) silicone elastomer cap containing a trench with the cap aligned with the carbon nanotube sensor. The method includes using the integrated microsystem to detect the presence of a biomolecule based on changes in the electrical conductance or resonant frequency of the carbon nanotube matrix.