Cavity optomechanical transduction sensing of single molecules

TL;DR

This paper demonstrates a novel optomechanical transduction method using a silica microsphere to detect single molecules, including proteins and nanoparticles, with high sensitivity and potential for detecting very small molecules.

Contribution

It introduces a new optomechanical sensing approach capable of detecting single molecules as small as 3.9 kDalton, surpassing previous sensitivity limits.

Findings

Successfully detected 10-nm silica beads and BSA proteins.

Predicted detection of 3.9 kDalton molecules at SNR > 1.

Achieved narrow linewidth optomechanical oscillation in a microsphere.

Abstract

We report narrow linewidth optomechanical oscillation of a silica microsphere immersed in a buffer solution. Through a novel optomechanical transduction sensing approach, single 10-nm-radius silica beads and Bovine serum albumin (BSA) protein molecules with a molecular weight of 66 kDalton were detected. This approach predicts the detection of 3.9 kDalton single molecules at a signal-to-noise ration above unity.