Shopova S I, Rajmangal R, Nishida Y, Arnold S
MicroParticle PhotoPhysics Laboratory for BioPhotonics, Polytechnic Institute of New York University, Brooklyn, New York 11201, USA.
Rev Sci Instrum. 2010 Oct;81(10):103110. doi: 10.1063/1.3499261.
We demonstrate a significant reduction in the limit of label-free detection of individual viral-sized nanoparticles in aqueous solution through the use of a frequency doubled telecom laser constructed from a distributed feedback-periodically poled lithium-niobate (DFB-PPLN) union. By driving a whispering gallery mode biosensor near a wavelength of 650 nm with this device we have detected real-time adsorption steps for particles 36 nm in radius with a signal to noise ratio of 8. The noise equivalent detection limit is ∼20 ag (17 nm radius). This new lower limit is attributed to the ultralow resonance wavelength noise [(Δλ(r))(rms)/λ(r)<10(-9)] associated with the use of the DFB-PPLN device.
我们展示了通过使用由分布反馈周期性极化铌酸锂（DFB-PPLN）组合构建的倍频电信激光器，水溶液中单个病毒大小的纳米颗粒的无标记检测限显著降低。通过用该装置在650nm波长附近驱动回音壁模式生物传感器，我们检测到了半径为36nm的颗粒的实时吸附步骤，信噪比为8。噪声等效检测限约为20 ag（半径17nm）。这个新的下限归因于与DFB-PPLN装置的使用相关的超低共振波长噪声[（Δλ(r))(rms)/λ(r)<10(-9)]。
