I decided to show some of my results with the nanopipette in a website. I will start using some images I had in my first rotation talk at BME in November 21st, 2014. This I think will help me evaluate my progress in the research I am doing during my PhD.
Right now, I am not yet a specialist in nanopipettes or bioinformatics, so I am using my own language to share information.
The process of fabrication of a nanopippette allows it to be used to performe single cell analysis. The following picture shows a quartz capillary which is heated and pulled in order to make the tip.
The program I set the puller to fabricate the nanopipette with gives me 100nm opening diameter of pore. So as a MCF7 cell has approximately 18Ám in diameter you can imagine how we can approach a single cell: because of how big a cell is compared to the nanopipette. Now in order to perform a single cell analysis we need to couple the nanopipette to a microscope. The following picture shows a nanopipette coupled to a microscope and the use of two electrodes forming an electrical circuit. This circuit allows a software to collect the ellectical current to perform the search for a cell surface. This mechanism is called Scanning Ion Conductance Microscopy (SICM).
Once we used the microscope to see a cell and target it with a nanopipette on the top, we can now go inside the single cell. The electrical feedback control system is triggered and automatically the nanopipette is operated to performe a single cell penetrarion. This is an image we see using the inverted microscope coupled to a nanopipette to sample breast cancer cells (MCF7):
When the nanoppipete is inside the cell, we have a structure to target. In this first experiment, I was interested in sampling mitochondrial DNA. I used a pair of primers for a fragment of approximatelly 8 kB from the mitochondrial genome to be amplified in a PCR assay. The result bellow shows we succeded in amplifying this fragment. Our next goal is to target the nucleus of single cells.
In My Personal Website I share more research information. It contains also links to my MS thesis and for Brazilian students interested in an undergraduate or PhD course abroad as well as researshers interested in opportunities in Brazil through the Science without Borders program.