Universal sensor cartridge for use with a universal analyzer for sensing components in a multicomponent fluid

A re-useable, miniaturized cartridge for use in measuring at least two substances in solution adapted for insertion into a receptacle of predetermined dimension, comprising:

• a housing having upper and lower regions, said upper region having a chamber of predefined volume;
• a first inlet means for introducing the solution into said chamber,
• a second inlet means for introducing a calibration fluid into said housing;
• three substance sensitive means, two of said three substance sensitive means sensitive to one each of the substances and one of said three substance sensitive means sensitive to both of said at least two substances, each of the substance sensitive means being secured within said housing and having means for interfacing with said chamber and extending to the lower region of said housing;
• a reservoir for receiving fluid displaced from said chamber, said reservoir being contained within said housing and extending into the lower housing region,
• said reservoir having a fluid containing volume considerably greater than that of the chamber;
• a fluid flow impedance means being disposed between said sensitive means and said reservoir;
• wherein said lower housing region is adapted to be received within a complementary receptacle and said sensitive means establish signal contact with corresponding signal conductive elements within the receptacle.