Raman Academy - Read

In this application note, Raman spectroscopy is explored as an easier and more flexible technique for quantifying common components in a CMP slurry, such as benzotriazole and glycine, without any sample preparation or costly consumables.

2D materials are state-of-the-art in nano- and opto-electronics. Characterizing their structural properties with a non-destructive approach at the micron scale is very important.

We all consume or have all consumed sugary drinks at least once. Sugar content of those drinks must be regulated. Also, to avoid those properties of sugar, it has been replaced by sweeteners. These have lower sweetness than natural sugars. Whether it is sugar or sweetener, their content just be controlled. Here, we demonstrate that Raman spectroscopy is one solution to identify and evaluate sugar/sweetener concentrations in a quality control process.

Disinfecting your hands with hydroalcoholic gel has become a daily practice. In the meanwhile, 70° alcohol has been used for even longer to disinfect wounds. But, to remain efficient, the alcohol concentration of these products must not be below a defined threshold and must be controlled. This application note demonstrates how to evaluate alcohol concentrations in a quality control process with Raman.

Multilayer polymer films, composed of different materials, are used in a variety of industrial applications. The analysis of these multilayers is important to support, especially for safety and performances control. Here, we use Raman microscopy by cross-section analysis and confocal depth profiling to investigate the chemical composition of two multilayers films.

In this article, we present the combination of Raman spectroscopy, Photoluminescence and SEM-CL techniques, where the instruments weren’t physically connected. Smart nanostructured materials require a comprehensive understanding of their morphology, elemental and chemical composition. nanoGPS Suite solution allows a colocalized combination of a variety of microscopy techniques, providing a full characterization of nanostructured materials and a precise superimposition of the results obtained.

Due to the corona crisis, hand sanitizer became part of our daily routine. However, their use is not without potential risks because of their microplastics content. HORIBA offers all the tools necessary to analyze and characterize the presence of Microplastics in hand sanitizers: High-performance Raman microscopes, dedicated filtration kit, and especially the powerful particles detection software ParticleFinder™. We analyzed 3 samples of hand sanitizers, from different countries, and we were able to identify the different plastic content of each.

In this study we have chosen to investigate pyrite and its surrounding minerals in order to identify the different mineral phases as well as the chemical variations from micro- to nano-scale. Using the different microscopes instruments and being co-localized allows a comprehensive characterization of the sample and a precise superimposition of all the images.

In recent years, core-shell particles have attracted significant attention due to their smart properties. Size, morphology, and composition are the key features that strongly affect the performance and suitable applications of such structures.

Bipolar plates are key components of proton exchange membrane fuel cells – they notably distribute fuel gas and air and conduct electricity. Various materials and surface treatments have been developed to improve their properties. Here, we described a reverse engineering study on a bipolar plate from a commercial vehicle using GD-OES and Raman spectroscopy. The analyses revealed that the plate had an amorphous carbon coating on a titanium base plate.

In this article, we present how our Raman and X-Ray Fluorescence microscopies can be combined to shed some light on the origins of the universe. We show some examples on a meteorite piece and on water inclusion in quartz matrix.

Many challenges remain before the promise of 2D materials is realized in the form of practical nano-devices. An information-rich, nanoscale characterization technique is required to qualify these materials and assist in the deployment of 2D material-based applications.

The prevalence of allergies in the world is between 30 and 40%. Even though it exists medical treatments such as antihistaminic and desensitization this number is constantly increasing. Thus, in this application note, the identification and chemical characterization of aeroallergens by Raman microscopy will allow to prevent people who are affected by respiratory allergies of the presence of this type of allergens in indoor and outdoor air.

This Application Note outlines three different kinds of spectroscopic tools being used for the characterization of sunscreens, and discusses the obtained results. These include Fluorescence spectroscopy for photoactivity, Particle Size analysis for composition and Raman microscopy for formulation investigation.

In the food industry, the compounds characterization is a critical step to ensure the quality of the products or to provide information to customers which can be sensitive to allergies. In this application note, we showed how optical spectroscopies and laser diffraction can help for food compounds characterization, especially on a specific product, i.e. milks.

Pulsed RF Glow Discharge Optical Emission Spectrometry, coupled with the Ultra Fast Sputtering system, offers the Ultra Fast Elemental Depth Profiling of plastic thin films Polymer Mobile Screen Protection Covers. By coupling this technique with the Raman spectroscopy z-Scan analysis it is possible to acquire important information concerning the fabrication of smartphone screen protectors.

Raman spectroscopy is well known as a powerful analytical method for qualitative chemical analysis. Less well known is that under certain conditions Raman spectroscopy can also be an effective method for quantitative analysis. Here we demonstrate that capability for quantitative analysis under a variety of conditions, involving different solutes in a solution and solution mixtures, and its applications to pharmaceutical analysis such as content uniformity.

For the study of a pharmaceutical drug product, particle characteristics (count, size and chemistry) and compound distributions (size and spatial) are among key parameters that strongly determine the quality of the product due to their huge impact on the dissolution rate (and thus bioavailability) for the final solid dosage form. Laser diffraction and Raman microscopy were applied to highlight the benefits of combining two technologies for particle characterization.

Due to Covid-19, a wide choice of protective masks are now on the market. These types of masks are distinguished, in particular, by their different efficiencies linked to their filtration capacity. These differences in protective properties have therefore made it essential to characterize the composition of the masks. In this paper, we present why LabRAM Soleil™ confocal Raman multimode microscope is the perfect tool for studying the distribution and composition of mask fibers.

Both TEPL and TERS images are well correlated with AFM morphological images obtained simultaneously, and all are consistent in revealing the nature (number of layers) of MoS2 flakes. Upon deconvolution, the TEPL signal is even capable of revealing local inhomogeneities within a MoS2 flake of 100 nm size. Kelvin probe measurement supports TEPL and TERS measurements and adds to the power of such tip-enhanced combinative tools.

An imaging platform that combines Raman microscopy with enhanced darkfield and hyperspectral imaging technology was used to study lung tissue sections containing carbon nanotubes. It enabled easy identification of the regions containing the carbon nanotubes followed by spectroscopic characterization of chemical composition.

Plastic pollution from fishing gear is a global problem that harms the environment. Recycling of damaged or abandoned fishing gear is one way of mitigating the issue, however the exact nature of the polymer must be known in order to identify the correct recycling stream. In this paper, the MacroRAM benchtop Raman spectrometer with remote BallProbe® is used to quickly identify plastics used in various gillnet samples.

We have measured solutions of lysozyme under conditions known to effect its physical state in order to investigate the potential of Raman spectroscopy as a non-invasive and label-free tool to assess protein formulation stability. Results from this study identified specific Raman signature bands in this protein that can be used to identify individual amino acid residues that are reflect structural changes in proteins.

Segmented channel waveguides have been fabricated in single crystal KTiOPO4 through a topotactic process of partial cation exchange. The ion-exchanged waveguides maintain the high nonlinear susceptibility of KTiOPO4 to function as frequency doubling laser light sources. We apply three dimensional (3D) Raman imaging to understand and characterize the changes to the chemical bonding and crystalline structure as well as measure the volumetric structure of the waveguide segments.

In the final step of the formulation process, pharmaceutical and cosmetic industries have to control their products to check if the compounds' distribution in the final product, or in its application form, i.e. dispersed on a skin for an intracutaneous product, are homogenous and stable in order to guarantee the product's efficacy. In this paper, we present why confocal Raman microscopy is an excellent tool for product characterization after formulation.

In the polymer field, Raman microscopy has become one of the most important characterization tools due to the large number of chemical and structural information which could be extracted from a single result.

Since the physical state can affect the pharmaceutical behavior of drug substances, it is important to know what controls crystallization, solid state reactions, phase stability, and solubility.

One of the major challenges in the pharmaceutical development of a new product consists in its formulation, highly impacting the release and the efficiency of the active molecules in the body.

Natural rocks composing the Earth are complex. They consist of an aggregate of one or more minerals. Each mineral can be defined by its chemical composition and its crystalline structure and sometimes can also contain fluid inclusions. Geologists need a powerful characterization technique to get detailed information on the rock formation history.

Resulting from the combination of Raman spectroscopy and optical microscopy, Raman hyperspectral imaging has proven to be an indispensable tool in the pharmaceutical field. This article will broach a number of Raman hyperspectral imaging applications that were developed in our laboratory, in order to demonstrate the significance of the technique.

The scientific community is increasingly interested in environmental contamination by plastics. Recently, this interest in the contamination of aquatic systems by plastics has shifted to smaller particles, microplastics.

Confocal Raman Spectroscopy is an important analytical tool in various fields and it has shown high efficiency for specific applications in the cosmetic and/or pharmaceutical fields. Its non-invasive behavior, and its high molecular sensitivity make it one of the preferred label-free analytical techniques to characterize materials such as skin and cosmetic products.

With the increase of allergic disorders over the past years, fast and reliable techniques for characterization and identification of pollen types are required. The presented examples demonstrate that Raman microspectroscopy can be successfully applied to the analysis and the identification of airborne pollen.

The atmosphere contains a large variety of particles in suspension (aerosols) that differ in chemical composition as well as in size distribution depending on the region of the atmosphere, the meteorological conditions and the anthropogenic activity. Their dimensions range from a few nanometers to tens of micrometers and their atmospheric life time can be as long as several weeks so that they can impact the global as well as the regional climates.

It has been a problems for a long time for forensic scientists, customs officials and historians alike to be able to verify and authenticate printed documents just from the inks that have been used. It is a difficult and often impossible task to analyse an ink in-situ on a paper surface and techniques such as GC-MS and HPLC are fundamentally destructive requiring complicated extraction procedures to isolate the ink constituents before analysis.

Laser processing provides a fast, non-contact and flexible method of modifying and patterning materials, from glasses to metals. Micro-machining, thin layers ablation, two-photon polymerization are just a few examples of what has already been demonstrated.

Raman analysis of a 50 μm section of a wheat grain kernel has allowed spectral features corresponding to starch, lipid and proteins to be identified. The distribution of these components on the micron scale has been studied using a Raman mapped image. Decomposition of the Amide I band allows a correlation between protein structures and grain hardness.

The recent development of side-illuminated TERS analysis even provides the possibility to investigate the behavior of graphene-based structures under device operation.

We have performed a complete Raman polarized study of a single GaN nanowire using a confocal microscope together with a high resolution stage. The high spatial resolution of our Raman confocal instrument together with a piezoelectric stage demonstrates unambiguously the possibility to image the optical properties of nano-objects with a resolution better than 200 nm keeping the fill advantage of the polarization control under a confocal microscope.

Raman spectroscopy is a very well suited technique to determine both Ge fraction and strain in SiGe layers and Si cap layers. Moreover the possibility of using both UV and visible excitation lines on the same instrument is essential to study structures made up of a Silicon cap layer on top of a SiGe layer. The relative Ge content in the constant Si1-xGex layer is calculated from the visible Raman spectrum and the strain of the cap Si layer is derived from the UV Raman spectrum.

Raman spectra, in conjunction with Multivariate (Chemometric) Analysis, have been demonstrated to provide real-time information on the progress of a polymerisation reaction. As shown by this example, these results can provide unexpected information on the details of the reaction. in this case, the inequivalent reaction rates of the two monomers. Such information ultimately enables the process engineer to optimise his process.

The use of TERS to reveal the defects density in the structure of CNTs is of interest for a better understanding of the electrical properties of the devices made with such nano-objects. Not only defects concentration but also local chirality changes from the different radial breathing modes, pressure effect and strain distribution can be studied at the single carbon nanotube level through TERS.

As far as polymeric fibres are concerned, slight modifications of Raman features are directly related to differences in the molecular orientation and the degree of crystallinity of the fibres. To utilize these subtle spectral changes and correlate them with physical properties of the polymer, one is obliged to use Chemometrics on the Raman spectra.

Raman and resonance Raman spectroscopy have proven to be important research tools to investigate structure-function relationships in enzymes.

Using holographic techniques we have structured the surface in a one step procedure (no wet nor photocuring processing ) along the X and Y directions. A grating is first inscribed with grooves along the X direction, the sample is rotated by 90° and a second grating is inscribed with grooves along the Y direction. The intensity of the 1st diffracted orders is monitored to have equal intensities in both X and Y directions.

Recent developments in Raman instrumentation have made the technique easier to use, more compact, and more affordable. Consequently, all of the demonstrated potential of the spectroscopy for industrial uses can now be exploited, including its use in combination with statistical methods for concentration calibrations.

Blending, an alternative method for engineering products that combines the properties of polymer types is a physical mixing. It has the advantage of being not only simple and inexpensive, but also allows for re-cycling used material. The first part of this note concerns the dispersion of the two components in a polyethylene-polybutylene terephthalate blend. The chemical imaging capabilities of the LabRAM will be used to get this information. The second part deals with the depth analysis of laminated films made of different polymer layers.

The coupling of the power of confocal Raman microscopy to the inverted sampling geometry has enabled detailed investigations to be made of solvent and water based coating systems, providing important information on the processes and chemistry that occurs at the coating interface and within.

The natural scientific identification of pigments has some problems because of their insolubility in common solvents. Especially when one deals with examinations of evry small sample amounts or wishes to perform non-destructive analysis, e.g. in forensic laboratories or analysis of art paintings. Raman spectroscopy turns out to be an ideally suited technique to solve these analytical problems.

Leading experts generally base their certification of ancient artefacts on stylistic analysis and on personal sensory perceptions. However, greater objectivity is mandatory for identification and dating purposes. Different manufacturing technologies often result in products of very similar external appearance (from the visual and sensory points of view), but which differ completely in their micro/nanostructure.

The present study of mediaeval pigments using micro-Raman spectroscopy provides important information on the inorganic and organic type of pigments used in the wall paintings in the remains of the church in Skopsko Kale (Skopje Fortress).

There are two types of vibrational modes in MoS2 (as in all layered structures): vibrational modes inside layers (intralayer) and modes resulting from the movements of complete layers (interlayer).

Raman and photoluminescence spectroscopy and imaging are used to examine the spatial variation of solid state structure and electronic character of two dimensional (2D) WS2 crystals. Simultaneous acquisition of photoluminescence spectra with the Raman scattering provides complementary ways of rendering Raman and photoluminescence spectral images of thin film WS2.

Metal oxides, in contrast to most metals, are wekk known to be easily distinguished by their characteristic Raman spectra; their presence can be detected on a scale of micrometers with a Raman microprobe.

Raman has shown a high potential in characterizing the SWCNTs' structure. The correlation between knowledge about structure with physical and chemical properties about the tubes make the technique extremely powerful to control the quality of the SWCNTs for specific applications. Raman spectrometer capabilities like spatial resolution, spectral resolution and excitation wavelength versatility have been examined. Beside Raman, preliminary fluorescence studies are describing the potential of the technique.

The Raman spectra of the various forms of elemental carbon are very sensitive to the type of nearest neighbour bonding, and to intermediate and long range order. In many cases Raman spectroscopy is the technique of choice for characterization of carbon materials. Correlation of Raman spectral features with tribological properties can facilitate the deposition of carbon films.

Graphene is a new nanomaterial which may partially replace silicon in microcircuits and computer chips in the future. In order to better understand its quality characteristics, fast reliable techniques that deliver the right property measures are needed. Raman spectroscopy has emerged as a key technique for studying this exceptional material.

The Raman spectra of elemental carbon materials are known to be sensitive to polymorphy. For hard carbon films, the spectra of amorphous and diamond-like carbons can be band-fit to separate the contributions of the "graphitic carbon" (G band) from the "disordered carbon" (D band). The spectral behaviour of carbon films has been empirically correlated with thin film physical properties such as hardness, durability, optical transparency, electrical conductivity, thermal conductivity and corrosion resistance, and can be of use for prediction of these properties without extensive alternative testing.

The colour enhancement treatment on native brown and yellow diamonds can be highlighted by Photo Luminescence analyses performed with the Raman spectrometer LabRAM HR. The PL signature of green and violet diamonds has also been recorded. The defect centres responsible of the colour of the diamonds have all been detected and assigned. This proves the Raman spectrometer to be a very good tool to investigate the fine defects in the Diamond structure by Photoluminescence analysis.

The objective of the measurements is to identify the unknown components and their respective dispersion within pharmaceutical tabs by Raman and FT-IR microspectrometry.

Raman Spectroscopy is a powerful and widely used analytical tool within the pharmaceutical industry. Excipients and active pharmaceutical ingridients (APIs) can be analysed within seconds, and extensive Raman spectral libraries allow easy chemical identification.

In order to engineer materials with controlled diffusive properties, we need to be able to measure the diffusive process in situ. Ideally, we would like a technique that provides molecular information with resolution on a microscopic scale, that is non destructive of the samples, and can be set up and used on a laboratory bench top with a minimum of time and effort involved in sample preparation. Raman microprobe spectroscopy is an ideal candidate for this type of studies.

Pharmaceutical and crystallographic samples typically require detailed characterisation and analysis to optimise a samples stability, physical properties and indeed general efficacy where an active drug substance is involved. Furthermore, strict regulatory and manufacturing procedures demand precise characterisation of a solid salt form drug candidate and the possible influence of environmental conditions. The hydration and structure of such samples under varying conditions is important in this full characterisation.

Full and detailed characterization of pharmaceutical formulations is required before release of new drugs. When exposed to warm and humid weather over time, ingredients may undergo change in their hydration level, thus affecting the properties and/or efficiency of the drug. Raman spectroscopy, combined to a temperature and humidity controller can mimic such harsh conditions and can be used to monitor the properties of the different ingre-dients and track their modifications induced by environmental changes.

Resulting from the combination of Raman spectroscopy and optical microscopy, Raman hyperspectral imaging has proven to be an indispensable tool in the pharmaceutical field, especially to study the distribution of active(s) and excipients in a pharmaceutical drug product.

The use of the transmission raman mode instead of the traditional backscattering one brings additional flexibility for the analysis of material, especially when averaged information of bulky samples is required.

Raman Spectroscopy has many useful properties which can be explored and exploited in the analysis of pharmaceutical formulations.

During the last 5-10 years, the molecular solid state has gained recognition by the pharmaceutical industry for its role in drug manufacturing, stability, and activity. In addition, definition of the crystalline phase has become as important as molecular composition in patent protection.

A mouse model for human atherosclerosis has been developed in which the animals lack ApoE; these animals are called ApoE knock-out mice. These two measurements -the results of the aorta of an ApoE knock-out mouse and the results of the chemical study - indicate that the globule deposits contain cholesterol dissolved in fatty acid, and thus can be used as an early indicator of the atherosclerosis process in animal models during drug development.

Confocal Raman spectroscopy is beginning to be recognized as a high potential technique for the non invasive study of biological tissues and human skin under in vivo conditions. Raman spectroscopy can be applied to obtain information regarding the molecular composition of the skin down to several hundred micrometers below the skin surface.

In the soap industry, many chemical reactions are involved for the preparation of the final product. A hight control of the reactions is a major part of the quality control mission in these industries in order to ensure the non-invasivity of the final product on human skin.

Vibrational spectroscopic characterization can take place all along the catalyst life from the control of the synthesis of the precursor to the cpntrol of the catalyst regeneration via the analysis of the surface reaction mechanism.

By coupling Raman spectroscopy with microscopy, it is possible to obtain full spectral information with a spatial resolution in the order of 1 µm. However, Raman is a weak phenomenon, and its sensitivity is not always ideal, particularly when analysing what are often relatively low concentration of intracellular components.

Raman microscopy is a technique which has proven highly valuable in a wide range of applications. Within biomedical research, its relevance to highly selective identification of biomolecules including amino acids and proteins, DNA/RNA and chemotherapeutic drugs is fast being realised. However, the efficiency of Raman scattering is low, and collection times can be long, and detection limits high.

Raman Spectroscopy was evaluated as a non-invasive method of analysis of sperm DNA and the influence of UV irradiation on the sperm. The results show that Raman Spectroscopy, combined with multivariate analysis provide the reproducible and accurate information on DNA of sperm and the effect and location of damage.

Fast and non-invasive methods for clinical and non clinical investigations for biological tissue are more and more required. Raman imaging at micro scale can answer to crucial questions about the monkey brain tissue morphology and structural evolution.

Identification of contaminating microbes is an important public safety issue in many fields such as the control of food quality and the manufacture of pharmaceutical and cosmetic products. Previous research has shown the potential for Raman spectroscopy in combination with chemometric methods to investigate bulk samples as well as a single bacterium and yeast cell for classification on the species and strain level.

Traditionally, Raman has been a technique of the material scientist, physicist or chemist, but as instrumentation continues to evolve, the power of Raman in biological and medical applications is fast being realized, not least because of the high information content provided and an excellent tolerance for water.

Decreasing turnaround time is a paramount objective in clinical diagnosis. We evaluated the discrimination power of Raman spectroscopy when analyzing microcolonies from nine bacterial and one yeast species directly on solid culture medium after a shortened incubation time of 6 h (compared to 24 hour for macrocolonies). This approach, that minimizes sample preparation and culture time, would allow resuming culture after identification to perform downstream antibiotic susceptibility testing.

In this application note, SERS is used to study the behaviour of glycoprotein αIIbβ3 which plays a critical role in thrombosis (pathological blood clotting which can reduce or completely stop blood supply to tissues and organs, leading to myocardial infarction or stroke).

The application note explains how the Raman Spectroscopy can be helpful in the analysis of cathodes and anodes in Li-ion batteries. Today’s state of art of technology requires more reliable, more efficient and powerful energy sources. Lithium-ion batteries are thus of high interest. Raman spectroscopy adapts to the different stages of life of these batteries, such as the characterisation of new materials for more flexible systems, failure analysis; but also more standard analysis of used material during charge/discharge process, including structural and electronic properties, and even robust, automated QC tests.

In a quiet NYC neighborhood, a frustrated artist created forgeries of America’s Modernistic masters. Raman Spectroscopy did him in.