Planar Nanoneedles on-chip for intracellular measurements

We present for the first time a functional planar SiN-nanoneedle system for intracellular mass transport and in vivo electrophysiological measurements on-chip. Though several micro- or nanoneedles for cell research have been described in literature, no needles of this small size equipped with nanosized inner channels or electrodes have been reported. A propidium iodide assay verifies the excellent penetration performance of the nanoneedles with diminished leakage from the cell after insertion and release of the needle from HL60- cells. Hollow needles connected to on-chip sub-picoliter electrochemical dosing systems are in development

Lab-in-a-Cell: a microfluidic chip to study a single living cell

Introduction: The application of microchip techniques has really entered life science and has started to serve as a driving force for discovery in cell biology, neurobiology, pharmacology and tissue engineering. As the field of cellomics is expected to become a very important one, a chip to perform single cell analysis will be developed. Therefore, the chip has to consist of a sorting unit, sampling unit and a connection to an analysing unit. Methods: The research is divided in autofluorescence (AF) cell detection, electroporation, needle puncture and picosampling. AF cell detection and localization has been performed on a microfluidic glass chip using granulocytes and red blood cells. For electroporation, cells are trapped and electrodes generating a high electrical field create pores in the cell membrane. Further, siliconnitride microneedles (260nm thick) have been made to analyse needle puncture through a cell membrane. Results: With confocal microscopy, it is possible to sort red blood cells from granulocytes on a microfluidic glass chip on the basis of their intrinsic AF. Further, non-viable cells were distinguished from viable cells due to a lower AF intensity. For the sampling unit, an electroporation device and sharp needles have been made to be able to manipulate a cell. Extraction of cell fluid from oocytes has been performed. Conclusion: Our results show the possibility to manipulate and analyse single living cells on chip. All units have to be organised on one fluidic-chip to be able to perform single cell analysis. Precise control of biochemical cellular environment and analysis of the composition of single cells will lead to Lab-in-a-Cel