On-Chip Microfluidic Reservoirs

Essentially two implementation strategies of this concept were developed and named nanofountain pen (NFP). In both cases, microchannels with typical sections of 300-500 nm by 2-10 pm were fabricated in the cantilever and its support using 

So far, the two systems developed differ by the position of the outlet connecting the channel to the tip. The tips developed by Deladi etal. are based on hollow, pyramidal atomic force microscope tips pierced with an aperture at the tip apex using an FIB in a NADIS-like configuration or, alternatively, at the base of the pyramid. The liquid is brought from the reservoir to the aperture by capillarity through the cantilever-borne microfluidic channels (Fig. 12.5a-c).  

An original outcome of the combination of microfluidics and apertured SPM probes is the development of FluidFM, which exploits the liquid dispensing directly at or close to a sharp atomic force microscope tip to deliver the solution on or through the cytoplasmic membrane of living cells in a liquid environment. The sensitive force feedback inherited from the SPM configuration provides a convenient way to approach the tip to the fluid membrane 

---