%0 Journal Article %1 https://doi.org/10.1002/smll.202305675 %A Huhnstock, Rico %A Paetzold, Lukas %A Merkel, Maximilian %A Kuświk, Piotr %A Ehresmann, Arno %D 2023 %J Small %K imported %N n/a %P 2305675 %R https://doi.org/10.1002/smll.202305675 %T Combined Funnel, Concentrator, and Particle Valve Functional Element for Magnetophoretic Bead Transport Based on Engineered Magnetic Domain Patterns %U https://onlinelibrary.wiley.com/doi/abs/10.1002/smll.202305675 %V n/a %X Abstract Controlled actuation of superparamagnetic beads (SPBs) within a microfluidic environment using tailored dynamic magnetic field landscapes (MFLs) is a potent approach for the realization of point-of-care diagnostics within Lab-on-a-chip (LOC) systems. Making use of an engineered magnetic domain pattern as the MFL source, a functional LOC-element with combined magnetophoretic “funnel”, concentrator, and “valve” functions for micron-sized SPBs is presented. A parallel-stripe domain pattern design with periodically decreasing/increasing stripe lengths is fabricated in a topographically flat continuous exchange biased (EB) thin film system by ion bombardment induced magnetic patterning (IBMP). It is demonstrated that, upon application of external magnetic field pulses, a fully reversible concentration of SPBs at the domain pattern's focal point occurs. In addition, it is shown that this functionality may be used as an SPB “funnel”, allowing only a maximum number of particles to pass through the focal point. Adjusting the pulse time length, the focal point can be clogged up for incoming SPBs, resembling an on/off switchable particle “valve”. The observations are supported by quantitative theoretical force considerations.

@article{https://doi.org/10.1002/smll.202305675, abstract = {Abstract Controlled actuation of superparamagnetic beads (SPBs) within a microfluidic environment using tailored dynamic magnetic field landscapes (MFLs) is a potent approach for the realization of point-of-care diagnostics within Lab-on-a-chip (LOC) systems. Making use of an engineered magnetic domain pattern as the MFL source, a functional LOC-element with combined magnetophoretic “funnel”, concentrator, and “valve” functions for micron-sized SPBs is presented. A parallel-stripe domain pattern design with periodically decreasing/increasing stripe lengths is fabricated in a topographically flat continuous exchange biased (EB) thin film system by ion bombardment induced magnetic patterning (IBMP). It is demonstrated that, upon application of external magnetic field pulses, a fully reversible concentration of SPBs at the domain pattern's focal point occurs. In addition, it is shown that this functionality may be used as an SPB “funnel”, allowing only a maximum number of particles to pass through the focal point. Adjusting the pulse time length, the focal point can be clogged up for incoming SPBs, resembling an on/off switchable particle “valve”. The observations are supported by quantitative theoretical force considerations.}, added-at = {2024-02-07T11:57:34.000+0100}, author = {Huhnstock, Rico and Paetzold, Lukas and Merkel, Maximilian and Kuświk, Piotr and Ehresmann, Arno}, biburl = {https://www.bibsonomy.org/bibtex/2e65d14036ac4991682682dc161bc1139/aimed}, doi = {https://doi.org/10.1002/smll.202305675}, eprint = {https://onlinelibrary.wiley.com/doi/pdf/10.1002/smll.202305675}, interhash = {ab194031a485eb23c46ad5cb290a74bd}, intrahash = {e65d14036ac4991682682dc161bc1139}, journal = {Small}, keywords = {imported}, number = {n/a}, pages = 2305675, timestamp = {2024-02-07T11:57:34.000+0100}, title = {Combined Funnel, Concentrator, and Particle Valve Functional Element for Magnetophoretic Bead Transport Based on Engineered Magnetic Domain Patterns}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/smll.202305675}, volume = {n/a}, year = 2023 }