2. Fix the mouse to the foam on the bench with medical adhesive
tape, and especially fixate the hind paw to keep the leg
straightly and the whole depilated thigh exposed (see Note 21).
3. Disinfect the skin on the thigh with medical alcohol using
sterile swabs.
4. Coat 100 μl electroporation buffer on the surface of the
target area.
5. Apply the microneedle roller on the thigh skin lightly and
continually roll over 10 times vertically and horizontally. The
conductive microchannel can be generated in the skin as shown
in Fig. 2.
6. Smear 10 μl nucleic acid solution on the treated skin (see Note
22).
7. Attach the flexible interdigitated electroporation array on the
thigh tightly to match the skin profile (see Note 23).
8. When the FIEA fully covers the thigh, start applying the configured pulses on the flexible electrode. Every single pulse can
cause a convulsion, which can help monitor whether the pulse
is successfully applied (see Note 24).
9. Remove mouse from the bench to a warm cage and observe it
until fully recover from anesthesia.
10. Clean FIEA and microneedle roller with DI water and medical
alcohol, and sterilize by a 30 min UV light exposure.
11. Store flexible electrode and microneedle roller in a dry
bio-clean container for the next usage.
12. Culture the mice and carry out desired analyses, such as whole
body fluorescence imaging, expression analyses or immunological assays.
4 Notes
1. The flat and smooth silicon wafer and oxide layer are used as
the substrate of Parylene film and sacrifice layer for releasing,
respectively. Any type of silicon wafers compatible with microfabrication is acceptable. 100–300 nm oxidation thickness is
recommended because it can be easily manufactured by thermal oxidation process and the consequence of releasing is
satisfactory.
2. Any reactive ion etching (RIE) equipment with high purity
oxygen gas path is usable, even an oxygen plasma cleaner.
3. Lithography equipment can be replaced by any other similar
machines with over 1 μm resolution.
Transdermal Delivery of Nucleic Acid Mediated by Punching and Electroporation
109
tape, and especially fixate the hind paw to keep the leg
straightly and the whole depilated thigh exposed (see Note 21).
3. Disinfect the skin on the thigh with medical alcohol using
sterile swabs.
4. Coat 100 μl electroporation buffer on the surface of the
target area.
5. Apply the microneedle roller on the thigh skin lightly and
continually roll over 10 times vertically and horizontally. The
conductive microchannel can be generated in the skin as shown
in Fig. 2.
6. Smear 10 μl nucleic acid solution on the treated skin (see Note
22).
7. Attach the flexible interdigitated electroporation array on the
thigh tightly to match the skin profile (see Note 23).
8. When the FIEA fully covers the thigh, start applying the configured pulses on the flexible electrode. Every single pulse can
cause a convulsion, which can help monitor whether the pulse
is successfully applied (see Note 24).
9. Remove mouse from the bench to a warm cage and observe it
until fully recover from anesthesia.
10. Clean FIEA and microneedle roller with DI water and medical
alcohol, and sterilize by a 30 min UV light exposure.
11. Store flexible electrode and microneedle roller in a dry
bio-clean container for the next usage.
12. Culture the mice and carry out desired analyses, such as whole
body fluorescence imaging, expression analyses or immunological assays.
4 Notes
1. The flat and smooth silicon wafer and oxide layer are used as
the substrate of Parylene film and sacrifice layer for releasing,
respectively. Any type of silicon wafers compatible with microfabrication is acceptable. 100–300 nm oxidation thickness is
recommended because it can be easily manufactured by thermal oxidation process and the consequence of releasing is
satisfactory.
2. Any reactive ion etching (RIE) equipment with high purity
oxygen gas path is usable, even an oxygen plasma cleaner.
3. Lithography equipment can be replaced by any other similar
machines with over 1 μm resolution.
Transdermal Delivery of Nucleic Acid Mediated by Punching and Electroporation
109