Toward Single Molecule Detection with Photonic Crystal Microcavity Biosensors

Photonic crystal microarray nanoplatform for high throughput detection of biomolecules

“…In spite of significant research performed in semiconductor optofluidic detection and integration by various groups [12] to achieve sensing of individual species, sometimes to single molecule levels [13], limited research has been performed to achieve multiplexed label-free miniaturized lab-on-a-chip optofluidic protein microarrays. It must be noted that the detection principle of our device is significantly different from fluid sensing techniques demonstrated using photonic crystal waveguides only [14][15][16], which rely on shifts of photonic crystal band edge upon sensing and thereby can identify only one analyte at a time (since there is only one stop gap), or research performed that couples light straight from a standard ridge waveguide into a single photonic crystal microcavity [17][18][19] which can again identify only one analyte at a time. Multiplexed structures in two-dimensional photonic crystals have demonstrated modest quality-factors of the resonances [20].…”

Photonic Crystal Sensors

“…In order to avoid misleading the reader, it should be explicitly mentioned that single molecule detection has not yet been achieved with a PC sensor, however, there is a drive towards single molecule detection such as in [11]. Fig.…”

“…The change in the ∆λ is shown as a function of time for 1 µg/ml antibiotin binding to the sensor surface and for phosphate buffer saline, which represents the noise in the system. [11] In this PC sensor, time resolved biomolecular binding events between biotin and anti-biotin at various analyte concentrations were measured using microcavity resonators integrated with microfluidics. The optical field is confined to a volume of 33 × 10 −18 liters, which allows for monitoring of single binding events.…”

“…The techniques discussed will involve sensing of displacement, surface plasmon resonance (SPR), and most importantly, refractive index. Although there may be many applications of PC sensors, the few that exemplify the three techniques of detection that will be described include the ultrasensitive displacement sensor [8], SPR biosensor [9], ion sensor [10], single biomolecule detection [11], and ultracompact biochemical sensor [12]. The last three sensors listed will all deal with the detection of changes in the refractive index, since it is the most commonly implemented method of detection among PC sensors, especially PCWG sensors.…”

Silicon-nanomembrane-based photonic crystal nanostructures for chip-integrated open sensor systems

“…It must be noted that the detection principle of our device is significantly different from fluid sensing techniques demonstrated using photonic crystal waveguides only [34][35][36], which rely on shifts of photonic crystal band edge upon sensing and thereby can identify only one analyte at a time (since there is only one stop gap), or research performed that couples light straight from a standard ridge waveguide into a single photonic crystal microcavity [37][38][39] which can again identify only one analyte at a time. Multiplexed structures in two-dimensional photonic crystals have demonstrated modest quality-factors of the resonances [40].…”