A sensor cartridge for sensing at least one analyte in a sample, comprising: at least one sensor (74; 90; 92; 94; 96); a sample metering device, comprising: a sample holding chamber oriented between a sample entry port and a sample isolation unit and having a diluent introduction port disposed between entry port and sample isolation unit for introduction of a diluent into the sample holding chamber, wherein the volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines a metered volume of a sample for analysis; and a dilution chamber for mixing said diluent with the metered volume of sample to form a diluted sample, wherein said volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines said dilution chamber; a diluent package containing said diluent; a diluent conduit configured for transporting diluent from the diluent package to the diluent introduction port; and a pump configured to transfer said diluent through the diluent conduit and the diluent introduction port, and into said dilution chamber to form a diluted sample, and further configured to transport the diluted sample to the at least one sensor. at least one sensor (74; 90; 92; 94; 96); a sample metering device, comprising: a sample holding chamber oriented between a sample entry port and a sample isolation unit and having a diluent introduction port disposed between entry port and sample isolation unit for introduction of a diluent into the sample holding chamber, wherein the volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines a metered volume of a sample for analysis; and a dilution chamber for mixing said diluent with the metered volume of sample to form a diluted sample, wherein said volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines said dilution chamber; a diluent package containing said diluent; a diluent conduit configured for transporting diluent from the diluent package to the diluent introduction port; and a pump configured to transfer said diluent through the diluent conduit and the diluent introduction port, and into said dilution chamber to form a diluted sample, and further configured to transport the diluted sample to the at least one sensor. a sample holding chamber oriented between a sample entry port and a sample isolation unit and having a diluent introduction port disposed between entry port and sample isolation unit for introduction of a diluent into the sample holding chamber, wherein the volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines a metered volume of a sample for analysis; and a dilution chamber for mixing said diluent with the metered volume of sample to form a diluted sample, wherein said volume within the sample holding chamber between the diluent introduction port and the sample isolation unit defines said dilution chamber; a diluent package containing said diluent; a diluent conduit configured for transporting diluent from the diluent package to the diluent introduction port; and a pump configured to transfer said diluent through the diluent conduit and the diluent introduction port, and into said dilution chamber to form a diluted sample, and further configured to transport the diluted sample to the at least one sensor.