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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.

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.

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.

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.

Because Raman spectroscopy provides information on molecular composition, it is an ideal tool for studying chemical reactions. In particular it has been used successfully for studying polymerization where the change often involves the disappearance of a carbon double bond (>C=C<) as the polymer chain is lengthened by the addition of a monomeric group. In this note we will be looking at epoxy cure which is a reaction that causes cross-linking during the polymerization process to form a solid with fixed three-dimensional geometry.

Compound semiconductors including III-V, III-N materials and SiC are being growingly employed owing to their superior material properties over silicon semiconductors and their role in optimizing the energy efficiency of devices.

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.

The historically established group IV materials keep being the essential component of integrated circuits through more and more complex architectures (three dimensional: FinFET, Nanosheet FET, Gate-all-Around FET).

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.

The two-dimensional graphene and transition metal dichalcogenides materials are on their way to become the core of the future electronics devices. Controlling layer numbers and crystallinity at the wafer scale remains the main challenge.

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.

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.

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.

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 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. Use of visible light combined with a confocal microscope provides a probe with spatial resolution of a micron or better, and coupling of such a microscope to a modern Raman spectrometer equipped with holographic notch filters and CCD multi channel detectors allows rapid acquisition of Raman spectra which can be correlated with the chemical state of the species and its physical environment.

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.

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 characterization 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.

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.

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. Raman spectroscopy is demonstrated to be an excellent technique for identifying not only different types of polymers, but also different variants within a polymer class and additives including pigments.

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.

The assessment of microplastics in a marine environment is a multi-step process (sampling, extraction, detection and quantification of microplastics), in which each step is time consuming. Analyzing the chemical composition and morphology of microplastics represents a real challenge for answering crucial questions about the sources and fate of microplastics in aquatic environments. In this application note, we present a reproducible and time-effective method for fast and thorough morphological and chemical characterization of microplastics using a semi-automated scanning of particles coupled to micro-Raman spectroscopy. The rapid analysis of large number of collected particles allows for an exhaustive assessment of both large sample sizes and small subsamples.

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.

Raman microscopy is an excellent tool to address the polymer research. Raman microscopy can be used to characterize raw materials, to inline or outline monitor polymerization process, to investigate orientation and crystallization changes, and also to control the quality and traceability of genuine products, by understanding defects and compounds distribution. In this article we present how HORIBA Raman microscopy solutions can support the polymer chemical and structural understanding.

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.

The use of security features, such as luminescent inks, has increased significantly in an attempt to prevent fraud and counterfeiting of materials and goods. Obvious applications of these inks include banknotes, branded goods, drug packaging and food security. Security inks can either show up overtly or be covert, with the latter driving the luminescence further from the visible spectral region into the ultraviolet (UV) and near infrared (NIR) regions. These are regions where light sources are not so common. The use of the luminescence lifetime on top of the wavelength signature adds an extra parameter that can be interrogated.

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.

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.

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.

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.

Polymorphisms characterization of active molecules is one piece of important information for the pharmaceutical industry, not only on raw powders, but also in the final form. Raman microscopy remains the most appropriate solution for this application. In this paper, we present an example of polymorphisms characterization by Raman microscopy using the super low frequency module.

In order to control formulations of pharmaceutical products, characterizing their active compounds is critical, especially in terms of morphological and chemical characterization of particles. In this application note, two formulations from a generic and an innovator nasal spray have been analyzed to compare their compounds size and shape, and chemically characterized to compare the two formulations based on the ParticleFinderTM app for LabSpec 6. A focus is done on the active compound.

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. Raman spectroscopy is extremely information-rich (chemical identification, characterization of molecular structures, effects of bonding, environment and stress on a sample). With its non-destructive properties and high spatial resolution (< 1 μm), it is thus a tool of choice for geological studies.

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.

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.

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.

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.

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. The resulting synergism between Raman spectroscopy and Chemometrics will provide a powerful tool for monitoring and control of manufacturing of polymeric materials.

The transmission design has demonstrated to be the technique of choice whenever Raman spectral information of a bulk material is required. It has already proven its utility for pharmaceutical applications, as tablets or even powder mixtures are good candidates for this measurement mode. However, transmission Raman might be applied successfully to other sample types, such as polymers, bio-tissues or any translucent material, and can be envisaged for evaluating the content of product inside a package. In addition, as TRS provides a global spectral information of the measured sample, it will be a technique of choice when quantitative evaluation of mixtures is needed.

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.

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.

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. Incompatibility or non-miscibility of the differing chemical components is often an issue in the final performance of the polymer product. 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 are 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.

Pharmaceutical and crystallographic samples typically require detailed characterization and analysis to optimize a samples stability, physical properties and indeed general efficacy where an active drug substance is involved.

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.

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.

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.

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 demonstrate in this paper how LabRAM Soleil™ confocal Raman multimode microscope is the perfect tool for these materials characterization.

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.

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.

The TRIAX and iHR series spectrometers used in Raman system configurations provide superior imaging performance with no re-diffracted light and maximized optical throughput.

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.

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.

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.

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. TEOS characterization of 2D materials is likely to contribute to further deployment of these materials into commercial products through a better understanding of their electrical and chemical properties at the nanoscale.

Raman and photoluminescence spectroscopy reveal different aspects of the solid state structure of 2D materials. Raman and photoluminescence imaging performed simultaneously with one instrument reveals the spatial variation of the solid state structure and electronic properties of 2D crystals that is not revealed in reflected white light imaging. That ability should allow materials scientists to better design and fabricate electronic and optoelectronic devices based upon 2D crystals.

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.

The two methods - Analysis of fingerprint modes (intralayer) and Analysis of low-frequency modes (interlayer) - give complementary results and allow the determination of the number of MoS2 layers. Method 2 (using low frequency modes) gives excellent contrast; however it does not show single layer regions (which is related to the nature of the modes, rising from interaction between at least two layers). Method 1 (using fingerprint modes) shows all the layers, but the contrast is poorer, particularly for higher numbers of layers. The best result can be obtained combining the two methods. All the measurements (low-frequency and fingerprint) were done using ultra-low frequency ULFTM filters which allow a high throughput measurement in a full Raman range, down to <10 cm-1.

Raman has shown a high potential in characterising 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 DiskRam has been designed to automate the collection of Raman spectra from hard carbon coatings on computer hard disk media and the extraction of parameters that are well correlated with the properties of the films. The extracted information is output in spreadsheet format for SPC at a manufacturing facility.

The colour enhancement treatment on native brown and yellow diamonds can be highlighted by Photoluminescence 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.