Applications

The advancement of analytical methods and systems are paving the way for innovation in academic, industrial and government sectors. As a result of the fast-paced progress, more research questions are asked that surpass the limits of these technologies. The mIRage IR Microscope is now answering these questions using Optical Photothermal IR (O-PTIR) spectroscopy, as well as IR+Raman – simultaneous submicron IR and Raman microscopy. With more chemical characterization requirements being met, mIRage is ushering in the next generation of applications and technology developments in numerous industries.

Contamination

Successful identification of contamination is a critical step in ensuring product or process quality is maintained. With stricter control standards and the decreasing size of high-tech products, confidently identifying smaller features is becoming increasingly important. With submicron spatial resolution using a non-contact reflection mode, O-PTIR easily resolves the most challenging of contamination issues.

Submicron line scan of polystyrene beads embedded in epoxy

Left: Demonstration of ~400nm spatial resolution as determined from a line scan (at 100nm steps) across 1 µm diameter polystyrene beads embedded in epoxy and sectioned to ~300nm thick. Right: A sharp boundary of only ~400nm is observed on both sides of the polystyrene beads as the IR spectral features transition between the two components.

Film defect identification

Left: Optical image of defect in a 240 µm thick two layer film. Markers on image represent the location of subsequent O-PTIR spectral collection. Right: Spectra collected in the defect-free (red) and defect (blue) region of the sample. The spectra display peaks indicative of isotactic polypropylene (998 cm-1). Insert: In the plot of the varying intensities for the isotactic polypropylene peak, both on the defect and off, The film region shows consistent signal intensity, while the defect region shows significant variability.

Polymers

Polymers are present in virtually all products we interact with daily. With increasing environmental awareness, polymer science is looking at more novel and complex solutions to improve functionality and reduce environmental impact. These requirements often exceed the limits of traditional IR microscopy, especially when it comes to spatial resolution. The mIRage IR Microscope, with its unique submicron spatial resolution using a non-contact reflection mode technique, is able to meet even the most demanding of analytical and sample characterization needs.

Application note: Submicron resolution IR spectroscopy and imaging of multilayer films for food packaging

Submicron IR+Raman Microplastics

mIRage locates PS and PMMA beads in salt crystal mixture (difficult to tradition FTIR microscope) in hi-res IR images at key absorption bands
Distortion free spectra at hotspots confirm the identity of the microplastics and readily searched against IR database

IR+Raman spectroscopy for direct fiber characterization

O-PTIR spectra of PP-based nanofibers with 800 nm diameter

Imaging and spectroscopy of bioplastic laminates

Composite (red/green) single frequency images

O-PTIR Scan of Bioplastic Laminate

Linear sampling scan spanning 8.0µm measured every 100µm apart (plotted only every 200 nm and across 2 mm for clarity) across the boundary of the bioplastic laminate, moving from the pure PHBHx layer to the pure PLA layer.

Gradual spectral changes over the space much greater than the optical resolution suggest the mixed distribution of PLA and PHBHx without any sharp boundary.

No clear isosbestic point indicates that the system is not a simple binary mixture.

PLA and PHBHx contributions are overlapped and mingled in the fingerprint region

Little to no sample preparation of a multilayer film

Left: A multilayer packaging film block face sample with manually selected markers for subsequent O-PTIR spectra collection. Right: The spectra easily show difference sin composition of each layer.

Submicron spatial resolution between film layers

Left: An optical image of a food multilayer film sample. Right: Corresponding O-PTIR spectra spaced 500 nm apart, with clear spectral distinction.

Life science

From plant biology to medical research, life science is an ever expanding research field that has impact in numerous industries. Providing submicron spatially resolved chemical analysis on biological samples, in a label free and objective approach, has proven itself to be a difficult result to obtain. The mIRage IR Microscope has accomplished this with its non-contact reflection mode O-PTIR technique, and is unlocking numerous applications capabilities.

Submicron O-PTIR imaging of live cells in water

Left: Optical image of hydrated epithelial cheek cells in water. Middle: Key macromolecules are easily spectrally discerned and spatially isolated, with the lipid inclusion as small as 0.5-1 µm being easily resolved. Spectra are not corrected for water and therefore inclusive of water absorbances. Images were collected at 500 nm step size. Right: The measurements
were collected using a 0.5 µm step size in transmission mode.

IR+Raman analysis of red blood cells

Left: Optical image with selected 70 x 70 µm area for subsequent Raman imaging. Middle: Subsequent Raman image taken at 1583 cm-1. Right: IRaman spectra collected off of a selected red blood cell (~500 nm resolution).

IR imaging of mineral: protein distribution in mouse bone

Left: Hyperspectral array images of mouse bone taken at 1047 cm-1 (second from left) and 1660 cm-1 (second from right) show mineral and protein distribution, respectively. Right: Corresponding spectra taken from the inner bone, showing a higher absorption for phosphate.

Data courtesy of Prof. Nancy Pleshko, Dr. Mugdha Padalkar, and Jessica M. Falcon, Temple University

Microplastics contamination in oceans and waterways

An emerging environmental concern especially for ocean/aquatic life is microplastics pollution. With research continuing to increase to assess the potential harmful affects to aquatic life and the food chain, accurate characterization and identification of microplastics is becoming critical. Microplastics are small plastic microscopic particles and fibers that range from 1micron to 5mm. Microplastics have been found in virtually all environments, from waterways, to wastewater, to the air we breathe and the food we eat. Owing to their small sizes (1 micron to 5mm) their accurate identification and morphological characterization can be challenging. O-PTIR, with its ability to measure submicron particles and fibers of varied sizes in far field reflection mode to yield FTIR transmission-like spectral quality regardless of particle shape and size, makes it the ideal technique for microplastics/particulate characterization. When coupled with simultaneous Raman (IR+Raman), it becomes an even more powerful tool that brings together the best of IR and Raman into a single measurement, for more thorough and accurate characterization for microplastics contaminants.

O-PTIR image and spectra of PS and PMMA dispersed in saline

mIRage locates PS (0.9 µm, 2.0 µm, 4.5 µm and 10 µm) and PMMA beads (3.0 µm) in salt crystal mixture in hi-res IR images at key absorption bands. Distortion free spectra, even amongst salt crystals at hotspots confirm the identity of the microplastics and readily searched against IR database. Importantly, and unlike traditional FTIR/QCL systems, spectra are consistent, regardless of particle shape or size when measured in reflection mode – no dispersive scatter artefacts

Application Notes

Submicron simultaneous IR+Raman spectroscopy for failure analysis of high technology components. Open PDF

Submicron, simultaneous and non-contact IR+Raman spectroscopy for direct fiber characterization. Open PDF

Submicron resolution IR spectroscopy and imaging of
multilayer films for food packaging. Open PDF