Four million people died in 2002 due to diabetes related conditions. Diabetes is the leading cause of adult blindness, end-stage kidney disease and amputations as a result of diabetic neuropathy. People with diabetes are two to four times more likely to have coronary heart disease and stroke than people who do not suffer from the disease. Complications associated with diabetes can be mitigated by proper treatment, such as more accurate and timely administration of insulin. Effective prevention of the complications associated with diabetes translates to cost-effective, ubiquitous health-care. Diabetes patients do not have to suffer.
Small, portable, actively sensing microfluidic bioassay devices can assist with the diabetic epidemic and other medical conditions that require multiple daily measurements.These micro devices can be fabricated using Integrated Circuit (IC) processes for creating microscale electrical and fluidic components using parallel processing techniques, minimizing system cost.
Portable bioassay systems require low power design due to power constraints associated with portable electrical energy sources. The water-powered bioassay system proposes to use chemical and surface energy to pump microliters of fluid to perform bioassays. For instance, the bioassay device will use an osmotic pump that makes use of expanding osmotic salts to pump fluid without requiring any electrical energy.
This thesis focuses on a microscale fluidic storage element that is part of the Water-Powered Bioassay effort, the Microfluidic Accumulator Driven by Capillary Forces, (MFA), shown in Fig. 1.1. The MFA uses surface energy to store fluid at an elevated pressure. The stored fluid may be dispensed at a later time. The microfluidic accumulator integrated with currently existing osmotic pumps will establish a system that does not require an external electrical energy source. It is postulated that these pumping systems will be utilized for inexpensive, low power, portable, microfluidic bioassay systems that will assist in mitigating deaths due to diabetes and other medical conditions.
May 31, 2003
Hobbs, E. D. (2003). Microfluidic Accumulator Driven by Capillary Forces: Research Project. United States: University of California, Berkeley.