A gas sensor utilizing carbon nanotubes (CNTs) is disclosed. The sensor can include a patch antenna, a feed line, and a stub line. The stub line can include a carbon nanotube (CNT) thin-film layer for gas detection. The CNTs can be functionalized to detect one or more analytes with specificity designed to detect, for example, environmental air contaminants, hazardous gases, or explosives. The sensor can provide extremely sensitive gas detection by monitoring the shift in resonant frequency of the sensor circuit resulting from the adsorption of the analyte by the CNT thin-film layer. The sensor can be manufactured using inkjet printing technologies to reduce costs. The integration of an efficient antenna on the same substrate as the sensor enables wireless applications of the sensor without additional components, for wireless standoff chemical sensing applications including, for example, defense, industrial monitoring, environmental sensing, automobile exhaust analysis, and healthcare applications.