Whitesides has developed a low-cost and portable microfluidic immuno-assay kit for use in the field. The device uses amplification chemistry based on silver deposition on gold-conjugated antibodies. It is compatible with microfluidic flow, and is easily detected by a battery-operated detector or by eye. The device exhibits high sensitivity, and can detect anti-HIV antibodies in a sample of human serum diluted 10,000-fold. The device is robust and uses inexpensive components, making it suitable for deployment in the third world where there is a strong need for this sort of instrumentation. This work couples well to the effort lead by Edwards, whose course in bioengineering has spawned a non-profit start-up, MEND, or Medicine in Need, which is dedicated to the development of an inexpensive cure for TB for the third world.