A MXene/PDA/PLLA conduit with capacitive coupling response for wireless stimulation induced cell nerve...

Electrical stimulation is limited in promoting peripheral nerve regeneration due to its reliance on external electrodes and wires. Herein, a wireless powered system is constructed based on capacitive coupling effect. In detail, an insulated copper sheet as the transmitting electrode, and a MXene/PDA/PLLA nerve conduit with a three-dimensional continuous conductive network served acts as the receiving electrode. After applying high-frequency AC voltage to the transmitter, the alternating electric field induces periodic charge redistribution on the conduit, generating a microcurrent that flows through the surrounding tissue. Phase-field simulations reveal that the conductive network originates from MXene segregation and interconnection at grain boundaries during laser sintering, which facilitates charge transport. Finite-element analysis confirms that the alternating field reverses the conduit surface potential and induced current direction cyclically, producing a localized electric field around the conduit. Meanwhile, the conduit exhibits approximately twofold increases in charge storage and current density. At an excitation voltage of 1.5 V (5 MHz), it delivers an output current of 276.5 μA and an output voltage of 478.7 mV, matching cell nerve differentiation. The induced current activates voltage-gated calcium channels, leading to a 2.5-fold increase in Ca²⁺ influx and a 2.9-fold upregulation of the nerve stem cell marker Nestin, thereby driving the nerve lineage commitment of BMSCs. This study designed a wireless electrical stimulation strategy based on capacitive coupling to boost cell nerve differentiation.