In recent years, both the diagnostic and pharmaceutical industries have
begun to seek improved methods of reagent dispensing that would enable
them to reduce the amount of reagent used, improve the accuracy and
repeatability of the quantities dispensed, and generally expedite the
processing of assays and microarrays. This work specifically presents
the development of a piezo- actuated microfluidic dispensing system for
microdrops generation with real-time closed-loop pressure control that
can operate in a drop-on- demand mode using a non-contact liquid
transfer method. This system can potentially generate droplets with very
high accuracy up to several picoliters in order to generate very
high-density microarrays. A simple mathematical model is developed and
used in order to perform simulations that are utilized as a tool by
which some of the system's design parameters are optimized. Moreover,
detailed finite element analysis was used in order to optimize the
overall design, assess the performance of the system, and define
suitable operating parameters.