Error-Oblivious Sample Preparation With Digital Microfluidic Lab-on-Chip
Sprache des Titels:
Microfluidic chips are now being increasingly used
for fast and cost-effective implementation of biochemical protocols.
Sample preparation involves dilution and mixing of fluids in
certain ratios, which are needed for most of the protocols. On a
digital microfluidic biochip (DMFB), these tasks are usually automated
as a sequence of droplet mix-split steps. In the most widely
used (1:1) mix-split operation for DMFBs, two equal-volume
droplets are mixed followed by a split operation, which, ideally,
should produce two daughter-droplets of equal volume (balanced
splitting). However, because of uncertain variabilities in fluidic
operations, the outcome of droplet-split operations often becomes
erroneous, i.e., they may cause unbalanced splitting. As a result,
the concentration factor (CF) of each constituent fluid in the
mixture may become erroneous during sample preparation. All
traditional approaches aimed to recover from such errors deploy
on-chip sensors to detect possible volumetric imbalance, and
adopt either checkpointing-based rollback or roll-forward techniques.
Most of them suffer from significant overhead in terms
of assay-completion time, reactant-cost, and uncertainties in
termination due to randomly occurring split-errors. In this paper,
we propose a new approach to accurate dilution preparation on a
DMFB that is oblivious to volumetric split-errors. It does not need
any sensor and can handle multiple split-errors, deterministically.
The proposed method is customized for each target-CF based on
the criticality of split-errors in each mix-split step. Simulation
experiments on various test-cases demonstrate the effectiveness
of the proposed method.
Sprache der Kurzfassung:
Transactions on Computer Aided Design of Integrated Circuits and Systems (TCAD)