ICP power/10 W RF power/30 mT APC pressure) is used
which has an etch rate of ~3 μm/min.
2. PDMS spacers (2 mm thickness) are cured by mixing a 10:1
ratio of prepolymer and the curing agent. The support platform, substrate, and two clamps are made of PMMA and
machined using a digital micromilling machine.
3. The permalloy deposited adjacent to each pore is in a disk with
dimensions of 15 μm in diameter and 50 nm thick. During chip
fabrication, the chip is coated in a thin layer of SiO 2 to protect
the magnetic traps and to realize electrical isolation.
PEG-silane is used to modify the surface of the chip before
each experiment to prevent cell adhesion during transfection.
4. To prevent antibody-coated beads and cells from adhering to
the substrate, the entire substrate is coated with a 1 nm seed
layer of permalloy followed by a 2 nm layer of gold. The sample
is then submerged in a solution of 1 nM triethylene glycol
mono-11-mercaptoundecyl ether (from Aldrich, St. Louis,
MO) in ethanol for 12 h, and rinsed with ethanol.
5. All cells are linked with superparamagnetic beads to enable
remote control of the cells by weak external magnetic fields.
Dextran-coated magnetic microbeads (1 μm diameter, StemCell Technologies, Cat. No. 19250) are attached to cells via
CD45 antigen, which is expressed on all cells used in this study.
6. Four electromagnets are used for the x–y plane, two for each
direction. The z-direction uses a solenoid to control the magnetic forces.
7. Low conductivity isotonic buffer solution is necessary so that
the conduction of the electric field will pass through or near the
cell. This allows for a positive dielectrophoresis (pDEP) to be
used to hold the cells in place.
8. Cell cannot keep healthy in sucrose solution for more than 1 h.
9. The alignment of the microcaps around the nanopores is necessary for electroporation to be effective.
10. The square wave function is the signal most commonly used for
3D NEP experiments.
11. Sigma Plot has an analysis button that can run the two-sided ttest, which is used to determine the significance for data with
normal distribution and equal variances. A standard p-value set
in all our experiments is 0.05.
References
1. Wang HY, Lu C (2006) Electroporation of mammalian cells in a microfluidic channel with geometric variation. Anal Chem 78(14):5158–5164.
https://doi.org/10.1021/ac060733n
2. Klein RM, Wolf ED, Wu R, Sanford JC (1992)
High-velocity microprojectiles for delivering
nucleic acids into living cells. 1987. Biotechnology 24:384–386
40
Lingqian Chang et al.
which has an etch rate of ~3 μm/min.
2. PDMS spacers (2 mm thickness) are cured by mixing a 10:1
ratio of prepolymer and the curing agent. The support platform, substrate, and two clamps are made of PMMA and
machined using a digital micromilling machine.
3. The permalloy deposited adjacent to each pore is in a disk with
dimensions of 15 μm in diameter and 50 nm thick. During chip
fabrication, the chip is coated in a thin layer of SiO 2 to protect
the magnetic traps and to realize electrical isolation.
PEG-silane is used to modify the surface of the chip before
each experiment to prevent cell adhesion during transfection.
4. To prevent antibody-coated beads and cells from adhering to
the substrate, the entire substrate is coated with a 1 nm seed
layer of permalloy followed by a 2 nm layer of gold. The sample
is then submerged in a solution of 1 nM triethylene glycol
mono-11-mercaptoundecyl ether (from Aldrich, St. Louis,
MO) in ethanol for 12 h, and rinsed with ethanol.
5. All cells are linked with superparamagnetic beads to enable
remote control of the cells by weak external magnetic fields.
Dextran-coated magnetic microbeads (1 μm diameter, StemCell Technologies, Cat. No. 19250) are attached to cells via
CD45 antigen, which is expressed on all cells used in this study.
6. Four electromagnets are used for the x–y plane, two for each
direction. The z-direction uses a solenoid to control the magnetic forces.
7. Low conductivity isotonic buffer solution is necessary so that
the conduction of the electric field will pass through or near the
cell. This allows for a positive dielectrophoresis (pDEP) to be
used to hold the cells in place.
8. Cell cannot keep healthy in sucrose solution for more than 1 h.
9. The alignment of the microcaps around the nanopores is necessary for electroporation to be effective.
10. The square wave function is the signal most commonly used for
3D NEP experiments.
11. Sigma Plot has an analysis button that can run the two-sided ttest, which is used to determine the significance for data with
normal distribution and equal variances. A standard p-value set
in all our experiments is 0.05.
References
1. Wang HY, Lu C (2006) Electroporation of mammalian cells in a microfluidic channel with geometric variation. Anal Chem 78(14):5158–5164.
https://doi.org/10.1021/ac060733n
2. Klein RM, Wolf ED, Wu R, Sanford JC (1992)
High-velocity microprojectiles for delivering
nucleic acids into living cells. 1987. Biotechnology 24:384–386
40
Lingqian Chang et al.