Highly sensitive detection of biomolecules is of paramount interest in many fields including biomedicine, safety and eco-pollution. Conventional analyses use well-established techniques with detection limits B1 pM. Here we propose a pyro-concentrator able to accumulate biomolecules directly onto a conventional binding surface. The operation principle is relatively simple but very effective. Tiny droplets are drawn pyro-electro-dynamically and released onto a specific site, thus increasing the sensitivity. The reliability of the technique is demonstrated in case of labelled oligonucleotides diluted serially. The results show the possibility to detect very diluted oligonucleotides, down to a few hundreds of attomoles. Excellent results are shown also in case of a sample of clinical interest, the gliadin, where a 60-fold improved detection limit is reached, compared with standard ELISA. This method could open the way to a mass-based technology for sensing molecules at very low concentrations, in environmental as well as in diagnostics applications.

The clinical assessment of Parkinson's disease (PD) symptoms is typically performed with neurological examinations and simple motor tests. However, this only takes into account the severity of motor symptoms during the length of the recording and fails to capture variations in a patient's motor state, which change continuously during the day. Most of the current methods for long-term monitoring of extrapyramidal symptoms are based on the use of a wearable magneto-inertial device that evaluates the frequential content of signals in the range of movement disorders. However, the typical daily motor activities performed by patients may have a power spectrum into the same range of motor symptoms, and habitual activity may be indistinguishable from that due to movement disorders. In this work, we report a new device and method for the continuous and long-term monitoring of tremor due to PD and other movement disorders to reduce the probability of mistaking the discrimination between extrapyramidal symptoms and normal daily activity. The method is based on the evaluation of frequential data content from multi-axial sensors and on the identification of specific movement patterns that Parkinsonian and extrapyramidal symptoms are typically associated with. In this study, 16 patients with movement disorders were recruited. While results need to be extended with further studies and clinical trials, the proposed device appears promising and suitable for the use as part of clinical trials and routine clinical practice for supporting the evaluation of motor symptoms, disease progression, and the quantification of therapeutic effects.

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A simple and rapid process for multiscale printing of bioinks with dot widths ranging from hundreds of microns down to 0.5 μm is presented. The process makes use of spontaneous surface charges generated pyroelectrically that are able to draw little daughter droplets directly from the free meniscus of a mother drop through jetting ("p-jet"), thus avoiding time-consuming and expensive fabrication of microstructured nozzles. Multiscale can be easily achieved by modulating the parameters of the p-jet process. Here, it is shown that the p-jet allows us to print well-defined adhesion islands where NIH-3T3 fibroblasts are constrained to live into cluster configurations ranging from 20 down to single cell level. The proposed fabrication approach can be useful for high-throughput studies on cell adhesion, cytoskeleton organization, and stem cell differentiation.

The pyro-electrohydrodynamic (EHD) manipulation of liquids has been discovered and demonstrated recently as a high resolution printing technique avoiding the use of nozzles and external electrodes. The activation of the pyro-electric effect is usually achieved on ferroelectric crystals by an external heating source or by an infrared laser. Here, we show an original modality for triggering the pyro-EHD process through a light-absorbing polymer nanocomposite thin layer deposited on the ferroelectric substrate, thus overcoming some limitations of the previous configuration. Significant simplification and compactness of the setup is achieved thanks to the nanocomposite coating, since a commercial low-cost white-light halogen lamp can be adopted to trigger the pyrojetting process from a liquid reservoir. Remarkably, high resolution is achieved in dispensing very high viscous liquids. Practical demonstrations in polymer optical microlenses direct printing using polydimethylsiloxane and poly(methyl methacrylate) are finally reported to validate the approach in handling high-viscous polymers for practical applications. V