Simonetta Grilli, Romina Rega, Emanuela Mazzon, Veronica Vespini, Simona Itri, Volodymyr Tkachenko, Pietro Ferraro, Sara Coppola, Martina Mugnano, Danila del Giudice, Emilia Oleandro, Canva, Michael T., Rega, R., Mugnano, M., Del Giudice, D., Itri, S., Tkachenko, V., Vespini, V., Coppola, S., Mazzon, E., Oleandro, E., Ferraro, P., and Grilli, S.
The effective detection of low-concentrated molecules in small volumes represents a significant challenge in many sectors such as biomedicine, safety, and pollution. Here, we show an easy way to dispense liquid droplets from few mu l volume (0.2-0.5 mu l) of a mother drop, used as reservoir, by using a pyro-electrohydro-dynamic jetting (p-jet) dispenser. This system is proposed for multi-purpose applications such as printing viscous fluids and as a biosensor system. The p-jet system is based on the pyroelectric effect of polar dielectric crystals such as lithium niobate (LN). The electric field generated by the pyroelectric effect acts electro-hydrodynamically on the sample of liquid, allowing the deposition of small volumes. The p-jet approach allows to obtain the dispensing of drops of very small volumes (up to tenths of a picoliter) avoiding the use of syringes and nozzles generally used in standard technologies. The reliability of the technique as a biosensor is demonstrated both in the case of oligonucleotides and in a sample of clinical interest, namely gliadin. The results show the possibility of detecting these biomolecules even when they are low abundant, i.e. down to attomolar. The results show a marked improvement in the detection limit (LOD) when compared with the conventional technique (ELISA). Moreover, it has been presented the possibility of using the p-jet as a useful tool in the detection of biomarkers, present in the blood but currently not detectable with conventional techniques and related to neurodegenerative diseases such as Alzheimer.