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Digital Microfluidics for Automated Proteomic Processing
Published on: November 6, 2009
Microfluidic analysis of complex samples with minimal sample preparation using gradient elution moving boundary
Elizabeth A Strychalski1, Alyssa C Henry, David Ross
1Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA. elizabeth.strychalski@nist.gov
Analytical Chemistry
|November 12, 2009
Summary
Gradient elution moving boundary electrophoresis (GEMBE) offers a robust method for analyzing complex samples like milk and blood. This microfluidic technique simplifies sample preparation for quantitative elemental and melamine analysis.
Area of Science:
- Analytical Chemistry
- Microfluidics
- Biotechnology
Background:
- Lab-on-a-chip devices aim for sample-in, answer-out analysis but struggle with minimally prepared complex samples.
- Existing microfluidic techniques are often confounded by particulates or proteins in samples like whole milk, dirt, coal fly ash, and blood serum.
Purpose of the Study:
- To develop and validate a microfluidic analytical method for complex samples with minimal preparation.
- To quantitatively analyze dissolved elements (potassium, calcium, sodium, magnesium, lithium) and melamine in diverse matrices.
Main Methods:
- Gradient elution moving boundary electrophoresis (GEMBE) was employed for analyte separation.
- Contactless conductivity detection was utilized for sensitive and non-invasive detection.
- Samples were analyzed after simple dilution or suspension in a sample buffer.
Main Results:
- GEMBE successfully analyzed complex samples including whole milk, dirt, coal fly ash, and blood serum.
- Quantitative analysis of potassium, calcium, sodium, magnesium, lithium, and melamine was achieved.
- The method demonstrated robustness in handling samples with particulates and proteins.
Conclusions:
- GEMBE is a simple, robust microfluidic technique suitable for analyzing complex samples with minimal preparation.
- Contactless conductivity detection simplifies device construction, enabling inexpensive and multiplexed implementation outside traditional lab settings.
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