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Updated: Jul 17, 2025

Creating Sub-50 Nm Nanofluidic Junctions in PDMS Microfluidic Chip via Self-Assembly Process of Colloidal Particles
Published on: March 13, 2016
Continuous-flow macromolecular sieving in slanted nanofilter array: stochastic model and coupling effect of
Sung Hee Ko1, Pyeong Jun Park2, Jongyoon Han3,4
1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA. sunghee.ko@nih.gov.
None:
Microfabricated slanted nanofilter arrays are a promising technology for integrated biomolecule analysis systems such as online monitoring and point-of-care quality validation, due to their continuous-flow and one-step operation capability. However, an incomplete understanding of the system limits the performance and wider applications of slanted nanofilter arrays. In this paper, we present rigorous theoretical and experimental studies on macromolecule sieving in a slanted nanofilter array. From both stochastic and kinetic models, an explicit theoretical solution describing size-dependent molecule sieving was derived, which was validated using experimental sieving results obtained for various sieving conditions. Our results not only detail the relationship between sieving conditions and sieving efficiency but also demonstrate that sieving is affected by multiple hindrance effects (electrostatic hindrance), not steric hindrance alone. There is an optimal sieving condition for achieving the greatest separation efficiency for DNAs of a certain size range. Small DNA has great size selectivity in small nanofilters and in weak electric fields, whereas large DNA is present in large nanofilters and in strong electric fields. This study provides insights into designing a slanted nanofilter array for particular target applications and understanding the sieving principles in the nanofilter array.

