Effective localized collection and identificationof airborne species through electrodynamicprecipitation and SERS-based detection

摘要

Various nanostructured sensor designs currently aim to achieve or claim single moleculardetection by a reduction of the active sensor size. However, a reduction of the sensor size hasthe negative effect of reducing the capture probability considering the diffusion-based analytetransport commonly used. Here we introduce and apply a localized programmable electrodynamicprecipitation concept as an alternative to diffusion. The process provides highercollection rates of airborne species and detection at lower concentration. As an example, wecompare an identical nanostructured surfaced-enhanced Raman spectroscopy sensor withand without localized delivery and find that the sensitivity and detection time is improved byat least two orders of magnitudes. Localized collection in an active-matrix array-like fashion isalso tested, yielding hybrid molecular arrays on a single chip over a broad range of molecularweights, including small benzenethiol (110.18 Da) and 4-fluorobenzenethiol (128.17 Da), orlarge macromolecules such as anti-mouse IgG (B150 kDa).