I developed 3D nano-spikes based system for biological manipulations and sensing, such as electroporation (EP), electric cell lysis (ECL), electroporation based protein extraction and impedance based cancer detection. Electrical methods are used for biological manipulations and sensing with low energy consumption due to electric field enhancement at 3D high-aspect-ratio nano-spikes (NSPs). Periodic 3D high-aspect-ratio nano-spikes were fabricated on low cost commercial Al foils using scalable electrochemical anodization and etching processes with controllable dimensions ranging from 600 nm to 1100 nm. Due to scalability of fabrication process, 3D NSPs were fabricated on microchips as well as on a 4 inch wafer. High EP efficiencies and cell viabilities (93±6%) for HeLa cells were achieve...[ Read more ]

I developed 3D nano-spikes based system for biological manipulations and sensing, such as electroporation (EP), electric cell lysis (ECL), electroporation based protein extraction and impedance based cancer detection. Electrical methods are used for biological manipulations and sensing with low energy consumption due to electric field enhancement at 3D high-aspect-ratio nano-spikes (NSPs). Periodic 3D high-aspect-ratio nano-spikes were fabricated on low cost commercial Al foils using scalable electrochemical anodization and etching processes with controllable dimensions ranging from 600 nm to 1100 nm. Due to scalability of fabrication process, 3D NSPs were fabricated on microchips as well as on a 4 inch wafer. High EP efficiencies and cell viabilities (>93±6%) for HeLa cells were achieved at 4 V for single pulse of 2ms and at 2V, 12 ms for 10 pulses on nano-spikes based electroporation (NSP-EP) chips by optimizing electric pulse protocol and NSPs dimensions. This applied voltage is more than ten times lower in comparison with planar electroporation (PEP) devices without NSPs. Low voltage operation avoided bubble generation on chips and increase device reliability and cell viabilities. I have developed an energy efficient 3D high-aspect-ratio nano-spikes based electric cell lysis (NSP-ECL) chips for efficient cell lysis due to electric field enhancement at NSPs. NSP-ECL chips have achieved high cell lysis efficiencies ƞ_lysis (99.9±0.1%) at more than ten times reduced pulse amplitudes (2 V) in comparison to the planar ECL chips without NSPs. These applied pulse amplitudes are 2-3 times reduced in comparison with traditional electroporation systems. The specific energy input required to achieve 99.9±0.1% ƞ_lysis was only in the range of 0.5-2 mJ/mL which is 3-9 orders of magnitude lower in comparison with other cell disintegration methods (5J/mL-540kJ/mL). I have developed an energy efficient method for intracellular protein extraction using electroporation on 3D nano-spikes with minimum cell invasiveness. The specific energy input required for protein extraction was in the range of 0.5-3 mJ/mL which is 4-8 orders of magnitude less than other classical methods. Cell membrane disintegration, cell debris micronization, and non-selective contaminant release was avoided durin protein extraction through reversible electroporation. I have developed 3D nano-spikes based Bio-impedance senor (nBIS) for label-free impedance detection and phenotyping of cancer and non-cancer cells. Electric signals were extracted directly from cell membrane by nano-spikes penetration into the cells. Charge transfer resistance R_ct was good electric indicator with 20-30% difference for detection and phenotyping of different cells.