Speaking of sensors, what do you do if you want your autonomous probe network to be able to monitor something other than salinity, temperature, or humidity? Monitor something biological, perhaps? NASA has something for you, a lab-on-a-chip designed to work in extreme environments on Earth, and eventually to go to Mars:

NASA researchers are developing complex, portable microarray diagnostic chips to test for all the genes and DNA responsible for determining the traits of a particular organism, detect specific types of organisms, or use biosensor-like probes such as antibodies to detect molecules of interest. By applying this technology in laboratories and in the field where organisms live in extreme environments on Earth, astrobiologists can compare Earth-life with that which may be found on other planets.

"The micro array chip system developed to go to Mars will be lightweight, portable and capable of detecting organic molecules," says Dr. Lisa Monaco, the project scientist for the Lab-on-a-Chip Applications Development program.  "This instrumentation can easily be adapted for monitoring crew health and their environment."

Such biosensing technology could have broad applications in agriculture, environmental research, healthcare, and (in particular) security, with the ability to detect trace amounts of pathogens. Not to mention helping us figure out if Mars actually does have life on it...