Abstract: A processor assembly including: an exposure station operable to expose a sample on a slide; a print station operable to apply a reagent to the exposed sample through a thermal inkjet process; and a robotic transfer mechanism to transfer the slide from the exposure station to the print station. Also, a reagent cartridge including: a body defining a container having a volume therein; a nonmetallic bag in the container operable to contain a reagent; and a printhead at a base of the body, the printhead coupled to an outlet of the bag. Further, a method including exposing a sample on a slide in a processor assembly; robotically transferring the slide to a printing station of the processor assembly; and applying a reagent to the exposed sample at the printing station by a thermal inkjet printing process.