Senior Josefina Biernacki wins Outstanding Student Designer Award

Josefina Biernacki, SB ‘26, was named among the winners of this year’s Analog Devices, Inc. (ADI) Outstanding Student Designer Award at the recent IEEE International Solid‑State Circuits Conference (ISSCC) 2026 in San Francisco.

The ADI Outstanding Student Designer Award recognizes a small group of students worldwide for exceptional promise in integrated‑circuit and systems design. Biernacki, who is studying electrical engineering at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), was selected for her work improving the platform for an intracellular microelectrode array (iMEA) chip that can perform massively parallel intracellular recordings of neurons, developed by the Donhee Ham Research Group. Her project is advised by Donhee Ham, the John A. and Elizabeth S. Armstrong Professor of Engineering and Applied Sciences at SEAS, with support from Yuchang Zhang, PhD student in the lab.

The silicon microelectronic chip contains an array of more than 4,000 “pixels” that enable large-scale intracellular recording and stimulation of neurons. Unlike traditional microelectrode arrays that measure signals outside cells with low signal-to-noise ratio, this platform measures intracellular voltages and currents, revealing synaptic connections and signals that are too small to be recorded with extracellular techniques. It does so by injecting a current into the cells to make the cell membrane permeable for intracellular access, and then measuring the voltages arising from synaptic events across thousands of neurons in parallel.

The permeabilization current is generated using circuitry that periodically delivers small packets of electrical charge, which introduces a small voltage ripple at the circuit’s switching frequency. Separately, the voltages from each pixel are recorded by a data acquisition system that samples the signal at its own clock rate. If the current clock and the data acquisition clock are not synchronized, the system may capture the signal at different points within the ripple cycle. As a result, the ripple can appear in the recorded waveform, sometimes dominating the measurement and obscuring the neuron’s true electrical activity.

To avoid this, Ham and his team are using a daughterboard functioning as a “patch” between the data acquisition system and the motherboard, synchronizing the current generator clock and the measurement clock before they reach the chip. This workaround solution required hand-tuning and added hardware complexity, limiting the adaptation of this technology outside of the Ham Research group.  

Biernacki redesigned the circuit board to integrate clock synchronization directly onto the motherboard, reducing the ripple artifact and allowing for higher fidelity neural recordings. The new platform design is reproducible and can be shared with other neuroscience labs, pharmaceutical companies, and neurotechnology developers interested in high‑throughput, intracellular electrophysiology.