Biochemical sensing in graphene-enhanced microfiber resonators with individual molecule sensitivity and selectivity

Abstract

Photonic sensors that are able to detect and track biochemical molecules offer powerful tools for information acquisition in applications ranging from environmental analysis to medical diagnosis. The ultimate aim of biochemical sensing is to achieve both quantitative sensitivity and selectivity. As atomically thick films with remarkable optoelectronic tunability, graphene and its derived materials have shown unique potential as a chemically tunable platform for sensing, thus enabling significant performance enhancement, versatile functionalization and flexible device integration. Here, we demonstrate a partially reduced graphene oxide (prGO) inner-coated and fiber-calibrated Fabry-Perot dye resonator for biochemical detection. Versatile functionalization in the prGO film enables the intracavity fluorescent resonance energy transfer (FRET) to be chemically selective in the visible band. Moreover, by measuring the intermode interference via noise canceled beat notes and locked-in heterodyne detection with Hz-level precision, we achieved individual molecule sensitivity for dopamine, nicotine and single-strand DNA detection. This work combines atomic-layer nanoscience and high-resolution optoelectronics, providing a way toward high-performance biochemical sensors and systems.

Solution-processed two-dimensional materials for ultrafast fiber lasers (invited)

“…For example, chemical vapor deposition (CVD) is a popular bottom-up method able to produce high-quality, large-area materials [44][45][46]. While CVD is used for applications such as integrated electronic devices [47,48] or transparent electrodes, for other applications such as solar cells, fuel cells, thermoelectric devices, or optical sensing systems [49][50][51][52], it is preferable to have the 2DMs dispersed in a liquid, which would make them easier to process and manipulate [53,54].…”

Micellization-induced amplified fluorescence response for highly sensitive detection of heparin in serum

“…The white precipitate was collected by vacuum filtration and washed with THF (500 mL). Yield: 96.5%; mp 166.6 °C; 1 Sample preparation. A 1 cm quartz cuvette was used for all spectral measurements.…”

“…Fluorescence techniques for efficient detection of chemical and biochemical analytes have been actively investigated because the intrinsic and extrinsic photophysics associated with the excited state of fluorophores provides a wealth of information about the structures, molecular behaviours, and binding interaction between the fluorescence matrix and analytes 1 . Functionalized fluorophores, the photophysical properties of which can be readily influenced by a variety of environmental factors, including solvent polarity, pH, and concentration, enable highly efficient fluoregenic detection with high sensitivity by controlling the photon in the excited states [1][2][3] .…”

“…Fluorescence techniques for efficient detection of chemical and biochemical analytes have been actively investigated because the intrinsic and extrinsic photophysics associated with the excited state of fluorophores provides a wealth of information about the structures, molecular behaviours, and binding interaction between the fluorescence matrix and analytes 1 . Functionalized fluorophores, the photophysical properties of which can be readily influenced by a variety of environmental factors, including solvent polarity, pH, and concentration, enable highly efficient fluoregenic detection with high sensitivity by controlling the photon in the excited states [1][2][3] . These probes must meet the requirements for efficient signal transduction and high luminescent efficiency, even in highly polar solvents or biological conditions, but most of the current probes rely on platforms such as polymers and metal-based nanoparticles as sensing tools, which exhibit relatively superior photophysical properties [4][5][6] .…”

Electrically controllable laser frequency combs in graphene-fibre microresonators

“…In optics, the symmetrically gapless dispersion of the quasiparticle Dirac fermions of graphene renders its optical permittivity to be defined only by the fine-structure constant 20 . This unique feature leads to a remarkable tunability in nonlinear absorption and phase shift 21,22 , thus enabling diverse optoelectronic modulators [23][24][25] , passively mode-locked lasers [26][27][28][29] , and photonic sensors [30][31][32] . Via tuning the carrier density electrically, graphene devices also enable distinct lasing tunability either in-fibre cavities or microresonators 16,33 .…”