Raman spectra tell a chip when to unclog a nanopore.

Scientists use tiny holes called plasmonic nanoporesplasmonic nanoporesTiny holes in a metal film that can trap particles and amplify light. to capture individual gold nanoparticles using electric voltage. This lets them run a sensitive chemical test that reads single molecules on the particles using light. However, particles can bunch up into clusters inside the hole. Clearing out these jams by hand is slow and exhausting, which ruins practical sensing work. To solve this, researchers built an automated setup using a microcontrollermicrocontrollerA small computer chip that can read sensor data and control devices.. The system gathers light signals from molecules on the particle surface over a long enough period to check them. It analyzes the signals in under 100 ms and quickly alters the voltage to eject stuck clusters. This automated process could allow fast, high-throughput testing and reading of DNA and proteins.

Why it matters

Researchers who study single molecules often use a tiny pore with a gold nanoparticle to amplify the Raman signal. But when multiple gold particles clump together in the pore, the measurement stops working. Cleaning the pore by hand is tedious. Now a microcontroller monitors the Raman signal and, in less than 0.1 seconds, zaps the pore with a voltage pulse to clear the clump automatically. This means machines can analyze DNA and proteins for hours without breaking down.

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