Attenuated Total Reflection Surface-Enhanced Infrared Absorption Spectroscopy: a Powerful Technique for Bioanalysis

Abstract

Attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) has recently been proven to be a powerful tool for bioanalysis. It enables in situ and in real-time observation of dynamic processes occurring on specific interface, revealing rich structural and functional information of biomolecules at sub monolayer level. The aim of this general review was to give an overview of the cutting edge applications of ATR-SEIRAS. We start with description of the basic configuration of the standard ATR-SEIRAS platform. The enhanced mechanisms and methods to fabricate enhanced substrates are then presented. We discuss the recent developments, challenges and applications of ATR-SEIRAS in bioanalysis, mainly focusing on DNA analysis, protein behavior and cell properties. Finally, further development of the ATR-SEIRAS technique with enhanced sensitivity, improved time and spatial resolutions will be prospected.

Antenna Enhanced Infrared Photoinduced Force Imaging in Aqueous Environment with Super-Resolution and Hypersensitivity

“…Mid-infrared (mid-IR) spectroscopy has attracted extensive attentions for interfacial studies since IR absorption of molecules arises from specific chemical bonds, allowing the analysis of molecular structures and functions without labelling or destruction. 1,2 Recently, atomic force microscopy (AFM) based opto-mechanical force detection techniques such as photothermal induced resonance (PTIR), [3][4][5][6] photoinduced force microscopy (PiFM) [7][8][9][10] and peak force infrared (PFIR) [11][12][13] microscopy have been demonstrated to achieve IR analysis with nanoscale spatial resolution, allowing subwavelength scale investigation of chemical and physical properties of molecules. At solid/gas interfaces, the detection sensitivity has hinted at molecular monolayer level, 3,7 which is promising to reveal information about the mechanisms of interfacial processes.…”

“…On solid/gas interfaces, the detection sensitivity has hinted at molecular monolayer level, 3,6 which is extremely promising to reveal information about the mechanisms of interfacial processes. However, challenges arise when applying opto-mechanical force based IR techniques in aqueous environment: (1) Decrease of the sensitivity due to the damping of cantilever oscillation in water; (2) Strong background water absorption of the incident light. 13 These intrinsic problems severely limit the range of application of AFM based IR techniques.…”

Au/ZnSe-Based Surface Enhanced Infrared Absorption Spectroscopy as a Universal Platform for Bioanalysis

“…Surface-enhanced infrared absorption spectroscopy (SEIRAS) is one of the essentially nonperturbing bioanalytical techniques for probing interfacial molecules and reactions with high sensitivity. , As an extension of conventional infrared spectroscopy, SEIRAS in attenuated total reflection (ATR) mode can significantly improve the detection sensitivity , and effectively provide structural and conformational information on biomolecules at the surface/interface, − while signal interference from the bulk solution and environmental variations can be markedly eliminated. Owing to these advantages, SEIRAS has been applied for the monitoring of interfacial protein conformation and function, ,− qualitative and label-free detection of various biomolecules, , and determination of specific recognition as well as structure–activity relationships of biomolecules .…”

Au–Ag core–shell composite nanoparticles as a selective and sensitive plasmonic chemical probe for l-cysteine detection in Lens culinaris (lentils)

“…In previous years, co-workers have exploited the use of FTIR for qualitative and quantitative analyses of biological and food samples, and various ionic species in the environment, based on the measurement of the selected characteristic absorption peaks of the analyte in the IR spectra. [32][33][34][35] In the present work, the preliminary investigations were performed with DRS-FTIR to determine the presence of the spectral bands of citrate-capped AuNPs and L-cysteine. Second, the freshly prepared standard solutions of dispersed and aggregated Au-Ag core-shell composite nanoparticles were analyzed to observe the characteristic IR absorption peaks of individual components, which were used to form bimetallic composite nanoparticles.…”