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Carosso, Nancy

Publications and source records attributed to Carosso, Nancy.

Alternate Protocol for Detecting Biological Contamination on Sensitive Hardware

The purpose of this project is to develop a sterile water based rapid bioburden test. Contamination engineers use two tests to assess the level of biological contamination on hardware: the rapid five minute bioburden test, which is a molecular screening for Adenosine triphosphate (ATP), a molecule found in all cells on the hardware, and a slower colony growth test, which is used to give a more accurate representation of the amount of microbes on the hardware. However, the rapid bioburden test has limited application because it leaves a residue that can be detrimental to sensitive hardware. This can cause project delays while waiting for the results from the three day colony growth test. We address this problem by adapting the commercial germicide based ATP system to a sterile water based system. The test works by reacting ATP with D-Luciferin and Luciferase protein to yield light. The light is then detected by a luminometer that outputs a Relative Light Unit (RLU) amount depending on how much ATP is present. To analyze the effectiveness of the new test, we developed a correlation between amounts of ATP and the RLU produced using the germicide based system. From these experiments, we've generated a consistent relationship between the two in the form of a power curve. From there, we developed a correlation curve between the amount of colonies and the RLU they produced. Initial tests of the new protocol have shown that the water based system isn't as sensitive as the germicide based test.

planetary protection↗

To-date spacecraft applications and demonstration testing results, and future product development for new molecular adsorber technologies

The use of molecular adsorbers, in order to aid in the reduction of the spacecraft contamination levels, is discussed. Molecular adsorbers are characterized by an extremely large surface area, molecularly-porous substructure, and processing charged sites capable of retaining molecular contaminant species. Molecular adsorbers were applied on two Hubble Space Telescope servicing missions, as well as on the tropical rainfall measuring mission. The use of molecular adsorbers carries the potential for low cost, easy fabrication and integration of reliable means for reducing the contamination level around spacecraft.

Thomson, Shaun↗