Figure 1.

(a) Schematic representation of transfer on skin of printed temporary tattoo electrodes (up) and wiring to external electronic device (down). Establishing easy-to-handle/reliable and stable interconnections represents a typical challenge for any ultrathin epidermal device. (b) Connection schematic section for a single electrode: the use of the soft and stretchable Ag ink allows the interface between materials of different thickness and Young’s moduli, i.e., the tattoo electrode (conformally attached to the skin) and the polyimide film. The external magnetic connection allows the communication with the external device. (c) The specific case-study: tattoo electrodes as real time respiration sensor based on four-point measurement of bio-impedance. (d) Schematic representation of the design and geometry of PEDOT:PSS electrodes and interconnections for transthoracic impedance measurements. (e) A TTE released on the chest of a subject (top) and the same docked through a magnetic connector used for signal acquisition.