Will Raman meet bacteria on Mars? An overview of the optimal Raman spectroscopic techniques for carotenoid biomarkers detection on mineral backgrounds

AbstractRaman spectroscopy appears to be an ideal technique for the initial detection of biomarkers, molecules that are potentially indicative of life on planetary bodies elsewhere in our solar system. Carotenoids are particularly useful biomarkers as they are used widely across the species, relatively resistant to breakdown and no inorganic source is known. They are used by microorganisms in their cell membranes for protection against UV radiation. In this paper we focus on the detection of carotenoids in microorganisms within a mineral matrix. We compare the Raman signatures of pure compounds with those of laboratory-made mixtures of β-carotene and minerals. Carotenoids covered by 2.5 mm of translucent calcite or 40 mm of transparent halite were detected using a conventional confocal Raman microscope. To improve sensitivity and hence detection levels, Raman measurements were successfully performed under resonant conditions. Raman analysis can be compromised by fluorescence interference. Data are presented to show how the contribution from the fluorescent background in the Raman spectra can be reduced when making use of gated detection in time-resolved Raman spectroscopy. Overall, this study demonstrates some of the potential of Raman spectroscopy as a method for the detection of (past) life signatures during future planetary missions without taking current technical limitations such as instrumental size into account as recent rapid technical developments suggest these limitations will be resolved in time.

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Recent advances in nano-photonic techniques for pharmaceutical drug monitoring with emphasis on Raman spectroscopy

Nanophotonics ◽

10.1515/nanoph-2019-0401 ◽

2019 ◽

Vol 9 (1) ◽

pp. 19-37 ◽

Cited By ~ 7

Author(s):

Timea Frosch ◽

Andreas Knebl ◽

Torsten Frosch

Keyword(s):

Raman Spectroscopy ◽

Drug Monitoring ◽

Surface Enhanced Raman Spectroscopy ◽

Signal Enhancement ◽

Therapeutic Drug ◽

Spectroscopic Techniques ◽

Widespread Application ◽

Pharmaceutical Drug ◽

Raman Spectroscopic ◽

Recent Advances

AbstractInnovations in Raman spectroscopic techniques provide a potential solution to current problems in pharmaceutical drug monitoring. This review aims to summarize the recent advances in the field. The developments of novel plasmonic nanoparticles continuously push the limits of Raman spectroscopic detection. In surface-enhanced Raman spectroscopy (SERS), these particles are used for the strong local enhancement of Raman signals from pharmaceutical drugs. SERS is increasingly applied for forensic trace detection and for therapeutic drug monitoring. In combination with spatially offset Raman spectroscopy, further application fields could be addressed, e.g. in situ pharmaceutical quality testing through the packaging. Raman optical activity, which enables the thorough analysis of specific chiral properties of drugs, can also be combined with SERS for signal enhancement. Besides SERS, micro- and nano-structured optical hollow fibers enable a versatile approach for Raman signal enhancement of pharmaceuticals. Within the fiber, the volume of interaction between drug molecules and laser light is increased compared with conventional methods. Advances in fiber-enhanced Raman spectroscopy point at the high potential for continuous online drug monitoring in clinical therapeutic diagnosis. Furthermore, fiber-array based non-invasive Raman spectroscopic chemical imaging of tablets might find application in the detection of substandard and counterfeit drugs. The discussed techniques are promising and might soon find widespread application for the detection and monitoring of drugs in various fields.

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Feasibility of Detecting Barrier Layer to Low-k Transition in Copper Cmp Using Raman Spectroscopy

MRS Proceedings ◽

10.1557/proc-867-w2.4 ◽

2005 ◽

Vol 867 ◽

Cited By ~ 1

Author(s):

S. Kondoju ◽

C. Juncker ◽

P. Lucas ◽

S. Raghavan ◽

P. Fischer ◽

...

Keyword(s):

Raman Spectroscopy ◽

Spectroscopic Method ◽

Spectroscopic Techniques ◽

Vibrational Modes ◽

Si Substrate ◽

Raman Spectroscopic ◽

Barrier Layers ◽

Copper Cmp ◽

Low K

AbstractIn copper CMP, transitions from copper to barrier as well as barrier to dielectric layer are typically sensed in situ using an optical reflectance technique. Spectroscopic techniques such as Raman, which allow monitoring the vibrational modes of silicon and low-k layers, have interesting potential for detecting these transitions. In this paper the use of Raman spectroscopy in detecting in situ removal of barrier layers from CDO materials is reported. Intensities of Raman peaks characteristic of Si-Si vibrations from Si substrate and C-H vibrations from low-k materials have been used for monitoring CDO layer thickness and detecting removal of Ta overlayer. An abrasion cell is integrated with a Raman spectrometer to demonstrate the feasibility of Raman monitoring in-situ. Capabilities and limitations of the Raman spectroscopic method are discussed.

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STUDIES ON NEPHRITE AND JADEITE JADES BY FOURIER TRANSFORM INFRARED (FTIR) AND RAMAN SPECTROSCOPIC TECHNIQUES

COSMOS ◽

10.1142/s0219607713500031 ◽

2013 ◽

Vol 09 (01) ◽

pp. 47-56 ◽

Cited By ~ 5

Author(s):

T. L. TAN ◽

L. L. NG ◽

L. C. LIM

Keyword(s):

Raman Spectroscopy ◽

Refractive Index ◽

Fourier Transform ◽

Quantitative Analysis ◽

Spectroscopic Data ◽

Fourier Transform Infrared ◽

Spectroscopic Techniques ◽

Raman Spectroscopic ◽

Specular Reflectance ◽

Wavenumber Region

The mineralogical properties of black nephrite jade from Western Australia are studied by Fourier transform infrared (FTIR) spectroscopy using both transmission and specular reflectance techniques in the 4000–400 cm-1 wavenumber region. The infrared absorption peaks in the 3700–3600 cm-1 region which are due to the O – H stretching mode provides a quantitative analysis of the Fe /( Fe + Mg ) ratio in the mineral composition of jade samples. The Fe /( Fe + Mg ) percentage in black nephrite is found to be higher than that in green nephrite, but comparable to that of actinolite (iron-rich nephrite). This implies that the mineralogy of black nephrite is closer to actinolite than tremolite. The jade is also characterized using Raman spectroscopy in the 1200–200 cm-1 region. Results from FTIR and Raman spectroscopic data of black nephrite jade are compared with those of green nephrite jade from New Zealand and jadeite jade from Myanmar. Black nephrite appears to have a slightly different chemical composition from green nephrite. Spectra from FTIR and Raman spectroscopic techniques were found to be useful in differentiating black nephrite, green nephrite, and green jadeite jades. Furthermore, data on refractive index, specific gravity, and hardness of black nephrite jade are measured and compared with those of green nephrite and of jadeite jade.

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Time-resolved stand-off UV-Raman spectroscopy for planetary exploration

Planetary and Space Science ◽

10.1016/j.pss.2014.01.010 ◽

2014 ◽

Vol 92 ◽

pp. 88-100 ◽

Cited By ~ 20

Author(s):

M. Skulinova ◽

C. Lefebvre ◽

P. Sobron ◽

E. Eshelman ◽

M. Daly ◽

...

Keyword(s):

Raman Spectroscopy ◽

Planetary Exploration ◽

Time Resolved ◽

Uv Raman Spectroscopy ◽

Uv Raman

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Time-Resolved Raman Spectroscopy

Encyclopedia of Spectroscopy and Spectrometry ◽

10.1016/b978-0-12-409547-2.12166-3 ◽

2017 ◽

pp. 463-468

Author(s):

H. Hamaguchi ◽

K. Iwata

Keyword(s):

Raman Spectroscopy ◽

Time Resolved

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Crystal structure and temperature-dependent properties of Na2H4Ga2GeO8 – a novel gallogermanate

Zeitschrift für Naturforschung B ◽

10.1515/znb-2020-0159 ◽

2020 ◽

Vol 75 (9-10) ◽

pp. 805-813

Author(s):

Irma Peschke ◽

Lars Robben ◽

Christof Köhler ◽

Thomas Frauenheim ◽

Josef-Christian Buhl ◽

...

Keyword(s):

Crystal Structure ◽

Decomposition Temperature ◽

Spectroscopic Techniques ◽

Charge Balance ◽

Temperature Dependent ◽

Raman Spectroscopic ◽

Debye Temperatures ◽

Diffraction Lattice ◽

Temperature Dependent Properties ◽

Balance Structure

AbstractSynthesis, crystal structure and temperature-dependent behavior of Na2H4Ga2GeO8 are reported. This novel gallogermanate crystallizes in space group I41/acd with room-temperature powder diffraction lattice parameters of a = 1298.05(1) pm and c = 870.66(1) pm. The structure consists of MO4 (M = Ga, Ge) tetrahedra in four-ring chains, which are connected by two different (left- and right-handed) helical chains of NaO6 octahedra. Protons coordinating the oxygen atoms of the GaO4 tetrahedra not linked to germanium atoms ensure the charge balance. Structure solution and refinement are based on single crystal X-ray diffraction measurements. Proton positions are estimated using a combined approach of DFT calculations and NMR, FTIR and Raman spectroscopic techniques. The thermal expansion was examined in the range between T = 20(2) K and the compound’s decomposition temperature at 568(5) K, in which no phase transition could be observed, and Debye temperatures of 266(11) and 1566(65) K were determined for the volume expansion.

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Combining Mechanistic Modeling and Raman Spectroscopy for Monitoring Antibody Chromatographic Purification

Processes ◽

10.3390/pr7100683 ◽

2019 ◽

Vol 7 (10) ◽

pp. 683 ◽

Cited By ~ 6

Author(s):

Feidl ◽

Garbellini ◽

Luna ◽

Vogg ◽

Souquet ◽

...

Keyword(s):

Experimental Data ◽

Raman Spectroscopy ◽

Estimation Procedure ◽

Mechanistic Modeling ◽

Spectroscopic Techniques ◽

Chromatographic Purification ◽

On Line ◽

Filter Approach ◽

Underlying Mechanisms ◽

Combining Information

Chromatography is widely used in biotherapeutics manufacturing, and the corresponding underlying mechanisms are well understood. To enable process control and automation, spectroscopic techniques are very convenient as on-line sensors, but their application is often limited by their sensitivity. In this work, we investigate the implementation of Raman spectroscopy to monitor monoclonal antibody (mAb) breakthrough (BT) curves in chromatographic operations with a low titer harvest. A state estimation procedure is developed by combining information coming from a lumped kinetic model (LKM) and a Raman analyzer in the frame of an extended Kalman filter approach (EKF). A comparison with suitable experimental data shows that this approach allows for the obtainment of reliable estimates of antibody concentrations with reduced noise and increased robustness.

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