The present invention provides methods of collecting and detecting compounds in a human breath sample, comprising: exhaling into a handheld sample collector to absorb at least one breath compound in an exhaled breath collector of said collector; connecting the handheld sample collector to a breath analyzer; transferring the breath compounds from the exhaled breath collector of the sample collector into the breath analyzer; and detecting breath compounds using two or more sensors. The method may be performed to detect breath compounds for determining health or disease diagnosis, or for drug monitoring.