Highly accurate biosensors for few or single molecule detection play a central role in numerous key fields, such as healthcare and environmental monitoring. In the last decade, laser biosensors have been investigated as proofs of concept, and several technologies have been proposed. We here propose a demonstration of polymeric whispering gallery microlasers as biosensors for detecting small amounts of proteins, down to 400 pg. They have the advantage of working in free space without any need for waveguiding for input excitation or output signal detection. The photonic microsensors can be easily patterned on microscope slides and operate in air and solution. We estimate the limit of detection up to 148 nm/RIU for three different protein dispersions. In addition, the sensing ability of passive spherical resonators in the presence of dielectric nanoparticles that mimic proteins is described by massive ab initio numerical simulations.

中文翻译：

---

使用自由空间回音廊模式微型激光器进行生物传感

用于少量或单分子检测的高精度生物传感器在许多关键领域发挥着核心作用，例如医疗保健和环境监测。在过去十年中，激光生物传感器已作为概念验证进行了研究，并提出了多项技术。我们在此提议展示聚合物回音壁微激光器作为生物传感器，用于检测低至 400 pg 的少量蛋白质。它们具有在自由空间中工作的优势，无需任何用于输入激励或输出信号检测的波导。光子微传感器可以很容易地在显微镜载玻片上形成图案，并在空气和溶液中工作。我们估计三种不同蛋白质分散体的检测限高达 148 nm/RIU。此外，从头算数值模拟。