Suspendable and Scalable Ultrasound‐Actuated ZnO‐Nanosheet‐Based Piezoelectric Microdevices for Wireless Electrical Stimulation of Cells

Why It Matters

The technology offers a non‑invasive, scalable platform for precise electrical modulation of individual cells, accelerating bioelectronic therapies and tissue‑engineering research.

Key Takeaways

• Subcellular-sized devices enable single-cell electrical interfacing
• ZnO nanosheets generate piezopotentials under ultrasound
• Calcium influx primarily via voltage‑gated and stretch‑activated channels
• 58% of cells activated using biomedical‑range ultrasound
• Scalable silicon microfabrication supports mass production

Pulse Analysis

Electrical stimulation is a cornerstone of modern biomedical research, yet conventional electrodes are limited by invasiveness, bulk, and difficulty targeting individual cells. Emerging bioelectronic strategies seek wireless, nanoscale solutions that can interface directly with cellular membranes without disrupting tissue architecture. By leveraging piezoelectric materials that convert mechanical energy into electrical signals, scientists aim to create devices that operate at the scale of a single cell, opening new avenues for precise modulation of cellular behavior.

The newly reported microdevices combine a micrometer‑scale silicon dioxide platform with vertically aligned ZnO nanosheets, a material known for strong piezoelectric responses. When cells exert intrinsic forces or when an external ultrasound field—tuned to safe biomedical frequencies—deforms the nanosheets, localized piezopotentials arise, depolarizing the membrane and prompting calcium transients. Pharmacological profiling pinpointed voltage‑gated calcium channels and stretch‑activated cation channels as the dominant conduits for ion influx, while intracellular stores played a minor role. Notably, ultrasound actuation alone activated more than half of the examined cells, confirming the efficacy of remote stimulation.

This breakthrough holds significant implications for the bioelectronics market. Scalable silicon microfabrication enables high‑volume production, reducing costs and facilitating integration into existing lab‑on‑a‑chip platforms. Potential applications span neuromodulation, cardiac pacing, and tissue‑engineered constructs where precise, cell‑level electrical cues drive differentiation and function. Moreover, the wireless nature of the devices minimizes infection risk and simplifies chronic implantation, positioning them as a compelling tool for next‑generation therapeutic and diagnostic technologies.