Improving sensitivity in micro‐free flow electrophoresis using signal averaging

Turgeon, Ryan T.; Bowser, Michael T.

doi:10.1002/elps.200800497

Cited by 21 publications

(22 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…More recent applications of μFFE have been designed to take advantage of this continuous analysis. For example, μFFE images can be averaged over time resulting in an improvement in signal to noise proportional to the square root of the number of images recorded 21. Fonslow and Bowser first demonstrated gradient μFFE as a method for determining optimum separation conditions for mixture of fluorescently labeled amino acids 22.…”

Section: Introductionmentioning

confidence: 99%

Measuring Aptamer Equilibria Using Gradient Micro Free Flow Electrophoresis

et al. 2010

Self Cite

View full text Add to dashboard Cite

Gradient micro free flow electrophoresis (μFFE) was used to observe the equilibria of DNA aptamers with their targets (IgE or HIVRT) across a range of ligand concentrations. A continuous stream of aptamer was mixed online with an increasing concentration of target and introduced into the μFFE device, which separated ligand-aptamer complexes from the unbound aptamer. The continuous nature of μFFE allowed the equilibrium distribution of aptamer and complex to be measured at 300 discrete target concentrations within 5 minutes. This is a significant improvement in speed and precision over affinity capillary electrophoresis (ACE) assays. The dissociation constant of the aptamer-IgE complex was estimated to be 48± 3 nM. The high coverage across the range of ligand concentrations allowed complex stoichiometries of the aptamer-HIVRT complexes to be observed. Nearly continuous observation of the equilibrium distribution from 0 to 500 nM HIVRT revealed the presence of complexes with 3:1 (aptamer:HIVRT), 2:1 and 1:1 stoichiometries.

show abstract

Section: Introductionmentioning

confidence: 99%

Measuring Aptamer Equilibria Using Gradient Micro Free Flow Electrophoresis

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…To date, stable μFFE separations have been demonstrated over a periods of minutes but longer separations have proven problematic 22 Figure 6. shows the separation of three fluorescent dyes (rhodamine 123, rhodamine 110, fluorescein) recorded over the course of approximately 2 hours in 25 mM HEPES at pH 7.00 with 300 μM Triton X-100 included in the carrier buffer.…”

Section: Resultsmentioning

confidence: 99%

“…Instead the formation of bubbles at the electrode surface due to electrolysis has proven to be the most difficult issue. These bubbles disrupt the flow pattern and electric field in the device, giving rise to unpredictable analyte flow paths 22. Devices fabricated which do not incorporate design aspects to mediate the effect of electrolysis bubbles are limited to very low applied voltages.…”

Section: Introductionmentioning

confidence: 99%

Using buffer additives to improve analyte stream stability in micro free flow electrophoresis

Frost

Bowser

2010

Lab Chip

Self Cite

View full text Add to dashboard Cite

Micro-free flow electrophoresis (μFFE) is a separation technique that continuously separates analyte streams as they travel through an electric field applied perpendicularly to the flow in a microdevice. Application of the technique has been limited by the generation of electrolysis bubbles at the electrodes, which results in unstable flow paths through the device. The current paper introduces the use of surfactants and nonaqueous solvents in the carrier buffer as a means of increasing stability of separated analyte streams. Adding surfactant or nonaqueous solvents lowers the surface tension of the carrier buffer, which we hypothesize promotes the formation of smaller electrolysis bubbles. A 6-fold improvement in the standard deviation of analyte stream position was observed upon addition of 10 mM SDS. Likewise, an approximately 12-fold improvement in stability was observed upon addition of 300 μM Triton X-100. Similar stability improvements were found in carrier buffers containing nonaqueous solvents. An 8-fold improvement in stability was found with a carrier buffer containing 50% methanol and a 6-fold improvement was found with a carrier buffer containing 37.5% acetonitrile. Long term use was demonstrated with a carrier buffer containing 300 μM Triton X-100 in which separated analyte streams remained stable for nearly two hours.

show abstract

“…The Bowser group from the University of Minnesota has made several contributions to FFE since 2008 [10][11][12]22]. In one study, Fonslow and Bowser used a microchip with varying depths to study the effects of a buffer concentration gradient on separations [10] and in another study, to separate mitochondria [11].…”

Section: Ffementioning

confidence: 98%

Recent developments in electrophoretic separations on microfluidic devices

2011

View full text Add to dashboard Cite

Research combining the areas of separation science and microfluidics has gained popularity, driven by the increasing need to create portable, fast, and low analyte-consumption devices. Much of this research has focused on the developments in electrophoretic separations, which use the electrokinetic properties of analytes to overcome many of the problems encountered during system scale-down. In addition, new physical phenomenon can be exploited on the microscale not available in standard techniques. In this study, the innovative developments, including electrophoretic concentration, sample preparation/conditioning, and separation on-chip are reviewed, along with some introductory discussions, from January 2008 to July 2010.

show abstract

Improving sensitivity in micro‐free flow electrophoresis using signal averaging

Cited by 21 publications

References 39 publications

Measuring Aptamer Equilibria Using Gradient Micro Free Flow Electrophoresis

Measuring Aptamer Equilibria Using Gradient Micro Free Flow Electrophoresis

Using buffer additives to improve analyte stream stability in micro free flow electrophoresis

Recent developments in electrophoretic separations on microfluidic devices

Contact Info

Product

Resources

About