Embedded passivated-electrode insulator-based dielectrophoresis (E pi DEP)

作者：Shake Tyler^*; Zellner Phillip; Sahari Ali; Breazeal Maria V Riquelme; Behkam Bahareh; Pruden Amy; Agah Masoud

来源：Analytical and Bioanalytical Chemistry, 2013, 405(30): 9825-9833.

DOI：10.1007/s00216-013-7435-7

• Dielectrophoresis (DEP)
• Escherichia coli (E. coli)
• Staphylococcus aureus (S. aureus)
• Microfluidic
• Microfabrication
• Insulator-based dielectrophoresis (iDEP)

Here, we introduce a new technique called embedded passivated-electrode insulator-based dielectrophoresis (E pi DEP) for preconcentration, separation, or enrichment of bioparticles, including living cells. This new method combines traditional electrode-based DEP and insulator-based DEP with the objective of enhancing the electric field strength and capture efficiency within the microfluidic channel while alleviating direct contact between the electrode and the fluid. The E pi DEP chip contains embedded electrodes within the microfluidic channel covered by a thin passivation layer of only 4 mu m. The channel was designed with two nonaligned vertical columns of insulated microposts (200 mu m diameter, 50 mu m spacing) located between the electrodes (600 mu m wide, 600 mu m horizontal spacing) to generate nonuniform electric field lines to concentrate cells while maintaining steady flow in the channel. The performance of the chip was demonstrated using Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial pathogens in aqueous media. Trapping efficiencies of 100 % were obtained for both pathogens at an applied AC voltage of 50 V peak-to-peak and flow rates as high as 10 mu l/min.

• 出版日期2013-12
• 单位美国弗吉尼亚理工大学(Virginia Tech)