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Abstract: This paper presents for the first time the design and fabrication of BioMEMS devices for living cells’ electrochemical impedance measurement under optical excitation. An interdigitated electrode design is adopted in order to increase the sensitivity of living cells’ impedance measurement. The magnitudes of the parasitic components were calculated and their influence on the chip performance was simulated. It is shown that our glass-based realization enables a very good performance up to a measurement frequency of 10MHz when the solution resistance is 1MΩ. The main difficulties that had to be solved in the fabrication process were related to adhesion and patterning of the various metal films, and especially to developing the correct bonding recipe. Unlike most of the reported data, no direct bonding was employed in the realization of our devices, but rather an intermediary polymer layer (e.g. SU8 or BCB) was used. The impedance of the devices with living yeast cells are measured with and without laser excitation at 532nm. The laser excitation also redistributes the cells, and the suspending cells in the PBS buffer settle down much quicker after the light excitation. [Copyright &y& Elsevier]

Life science is a field of dynamic development and can benefit from the usage of microelectronics in numerous applications. Various devices for separation of different (bio)chemical components from a mixture could be miniaturized in silicon, but they need detectors at their output to identify and characterize the separated elements.The colour sensor is such a detector, and it was preferred because other classical approaches typically used in chemistry or biology employ IR or UV-based analysis, for which it is more difficult to design, optimize and fabricate a silicon-based sensor.Unlike classical detection (using three different filters placed on separate detectors) the proposed device is based on an entirely different approach, using vertically stacked detectors within a single structure that can be fabricated using CMOS-compatible processing.The main requirements for the design of such a vertically stacked multi-junction structure are presented, together with details regarding the most critical processing steps and process parameter values obtained after simulation which were used in the manufacturing of the first version of the device, including some optical design aspects. [Copyright &y& Elsevier]

Electro-transfection serves as a promising non-viral gene delivery approach, but its performance faces several drawbacks associated with the high-voltage electrical pulses involved, which may adversely affect the cell viability. Here we developed a novel TENG (triboelectric nanogenerator)-driven nanowire electrode array (T-NEA) platform to facilitate the electroporation-based siRNA delivery into both adhesive and non-adhesive mammalian cells. Unlike conventional electroporation technology, the T-NEA system is powered by a TENG working in a vertical contact-separation mode, harvesting energy from simple human tapping motion. Since lower voltage is involved in the T-NEA system as compared to conventional electroporation method, high (>90%) cell viability was achieved for all of the six kinds of cell lines used in the experiments. Highly efficient siRNA electro-transfection was achieved at a tiny amount of energy consumption. The results exhibit that siRNA molecules could be successfully delivered into more than 95% of MiaPaCa-2 cell. Even for K562 cells, which is well-known as difficult-to-transfect cell, the delivery efficiency of siRNA reaches 84%. With the T-NEA system, the K-ras gene expression in MiaPaCa-2 cells was down-regulated by 46 ± 6.29%, and the bcr-abl gene expression was reduced by 31.6 ± 6.67% in K562 cells. When the expressions of the targeted mutation genes were significantly down-regulated, the cell proliferation and anti-apoptosis ability were significantly inhibited. Overall, the T-NEA system is demonstrated as an effective and versatile platform for high-throughput gene delivery in biological research and clinical cancer treatments due to its versatility, efficiency, and uniformity. Image 1 • Self-powered gene electro-transfection system. • Facile and low-cost fabrication process. • Easy operation and universality on different cell lines. • High siRNA transfection efficiency with low cell damage. • High inhibition efficiency on targeting oncogene expression. [ABSTRACT FROM AUTHOR]