Microfabrication of a BioModule composed of microfluidics and digitally controlled microelectrodes for processing biomolecules

Abstract

This work focuses on the development of an online programmable microfluidic bioprocessing unit (BioModule) using digital logic microelectrodes for rapid pipelined selection and transfer of deoxyribonucleic acid (DNA) molecules and other charged biopolymers. The design and construction technique for this hybrid programmable biopolymer processing device is presented along with the first proof of principle functionality. The electronically controlled collection, separation and channel transfer of the biomolecules is monitored by a sensitive fluorescence set-up. This hybrid reconfigurable architecture couples electronic and biomolecular information processing via a single module combination of fluidics and electronics and opens new fields of applications not only in DNA computing and molecular diagnostics but also in applications of combinatorial chemistry and lab-on-a-chip biotechnology to the drug discovery process. Fundamentals of the design and silicon-polydimethylsiloxane (PDMS)-based construction of these electronic microfluidic devices and their functions are described as well as the experimental results.

DNA accumulation on single-anode microelectrode structures and its application in active microarray layout design

“…This fact, although undesirable, is not crucial for the moment, as the work presented here does not aim at a subsequent hybridization of complementary ssDNA strands. Several approaches have been reported to date by other authors [4,6,19,[31][32][33][34], trying to avoid the electrochemical phenomena in experiments carried out always in the presence of an external electric field (sometimes a pulsed signal) on a large number of different devices (from variations of DNA microarrays to standard electrochemical cells).…”

“…Some preliminary work has been published using electronically controlled microarrays involving a large number of electrodes which are selectively polarized [4][5][6][7][8]. On the other hand, the influence of the surface probe density on the DNA hybridization efficiency has been investigated in a passive context (that is, with conventional DNA arrays in the absence of external sources), demonstrating that the surface density of the probe strands plays a crucial role in the subsequent hybridization [9].…”

Programming chemistry in DNA-addressable bioreactors

“…In such devices, dedicated microfluidic channels can be designed for vesicle generation [21], DNA tag insertion, tag and chemtainer trafficking [22], specific or unspecific fusion [23], vesicle rapture and encapsulation [24]. Possibly paired with real-time feedback, this allows for control of chemical reaction cascades at the molecular level.…”

An electrokinetic mixer driven by oscillatory cross flow

“…Study of the confined flow case also allows us to identify the mixing mechanism. In addition, while traditional microfluidic systems are based on continuous flow in channels, the newer emerging area of digital microfluidics is based on droplet handling (Fouillet and Achard 2004;Cho et al 2003;Paik et al 2003;Wagler 2003;Wheeler 2005), and confined mixing in which small quantities of fluids are mixed on a batch basis can be expected to be an important issue in such applications. Following the analysis of confined flows, continuous flow mixing is examined by modeling the effect of combining a fixed throughput flow with the EOF driven, oscillatory motion in a configuration called the star cell.…”