Atmospheric Monitoring for Infectious Agents
Level - UndergradThe Centers for Disease Control (CDC) has requested preliminary proposals for the design of a device that can detect presence of air-borne infectious agents. The device should be designed so that it is able to respond to the presence of the agents as rapidly and with as much sensitivity as is possible and is capable of remaining functional for two weeks or more in the field. The design that best meets these criteria will be fully funded to complete the design of the device.
The company that you work for has decided to compete for funding for this project. A team of researchers working for the company developed a prototype device containing a mammalian-cell (Chinese Hamster Ovary (CHO)) batch process bioreactor which exposes the cells to samples of the air surrounding the device. The device is based on the knowledge that dying cells often lose their membrane integrity and release proteins into the extracellular environment. The protein concentration in the medium is measured using the Bradford test. In theory, this protein concentration should be correlated to the concentration of the infectious agent the cells were exposed to. Initial testing of the device compared the measured protein concentration to a constant (with time) threshold value to determine if the infectious agent was present. Unfortunately this constant-threshold approach yielded, depending on the choice of the threshold, either unacceptably high false-positive or unacceptably high false-negative rates.
The project manager has decided that a better understanding of the how the protein concentration relates to time of exposure and the concentration of infectious agent is needed to improve the accuracy and sensitivity of the device. So the manager has recruited your team of biomedical engineers to develop a mathematical model of this relationship. To aid you in developing this model, you may ask the project manager (through your facilitator) questions regarding the design of the device.