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Society for Applied Spectroscopy
@sasspectroscopy.bsky.social
150 followers 13 following 300 posts
www.s-a-s.org

The Society for Applied Spectroscopy is a nonprofit organization formed to advance and disseminate knowledge and information concerning the art and science of spectroscopy.
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💼 Looking for a new role in spectroscopy or analytical science? Check out the latest openings on the SAS Career Postings page—your next opportunity may be waiting. Explore jobs: https://bit.ly/3LUQj6R
#SAS #Spectroscopy #Careers
Spectroscopy Jobs - Society for Applied Spectroscopy (SAS)
Society for Applied Spectroscopy (SAS) offers the top jobs available in Spectroscopy. Search and apply to open positions or post jobs on Society for Applied Spectroscopy (SAS) now.
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December 26, 2025 at 3:33 PM
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New from Applied Spectroscopy!
Interlaboratory Study to Minimize Wavelength Calibration Uncertainty Due to Peak Fitting of Reference Material Spectra in Raman Spectroscopy
Read Open Access 🔓: https://doi.org/10.1177/00037028251330654
#SAS #Spectroscopy #Raman #reference #material #peak #calibration
Abstract Raman spectroscopy is a powerful characterization technique with increasing applications that would greatly benefit from data harmonization. Several standards deal with calibration in Raman spectroscopy, but no detailed procedure covers the complete calibration of an instrument, including both spectral axes, from reference material spectra generation to data processing. Moreover, the type of reference materials, the quality of the recorded spectra and the choice of the fitting functions are critical for obtaining precise and reliable reference data for calibration. This report describes the challenges and importance of peak fitting for Raman signal calibration based on an interlaboratory study with 10 different instruments. Spectra of neon emission, silicon, calcite, and polystyrene were fitted using common peak shapes, observing that Gaussian, Pearson IV, Voigt, and Voigt shapes are preferred for these materials, respectively. An analysis of the effect on the fitting of the signal-to-noise ratio (S/N) recommends a minimum value of 100 for a Raman peak if it should be used to calibrate a Raman instrument. Some factors that might affect the peak shape of the Raman signal, such as the physical and chemical properties of the sample, the nature of the electronic transitions, the instrument response and the spectral resolution are discussed. The results highlight the role of peak fitting analysis in improving the quality and reliability of Raman spectra calibration and, thus, enhancing data transfer and comparability, especially for handheld and portable Raman analyzers, as well as applications based on quantification, multivariate data analysis, and other complex processing steps.
December 26, 2025 at 2:03 PM
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🎄 Merry Christmas from all of us at SAS! Wishing you a season filled with joy, peace, and time spent with loved ones.

#SAS #Christmas #HappyHolidays
December 25, 2025 at 2:11 PM
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New from Applied Spectrometry!
Quantitative Chemometrics Using Refractive Index Spectra
Read more: https://doi.org/10.1177/00037028251345774
#SAS #Spectroscopy #refractive #index #absorption #chemometrics
Abstract Classical quantitative chemometrics based on absorbance spectra has been routinely performed for approximately 40 years. Since absorbance is a function of the absorption index, it is natural to extend chemometric methods to the refractive index function. This function, related to the absorption index via the Kramers­–Kronig relations, is derived from corrections applied to absorbance spectra to ensure compliance with wave optics principles. In this note, we demonstrate that, at least in the quasi-thermodynamically ideal binary system of benzene and toluene, classical quantitative chemometrics performs better when based on refractive index spectra than when based on absorption index spectra. The primary reason for this difference is that the refractive index at a given wavenumber integrates all changes resulting from absorptions at higher wavenumbers. This property is particularly advantageous in non-absorbing regions, where absorption index spectra provide no information about the system's composition.
December 24, 2025 at 2:08 PM
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📢 The SAS offices will be closed Wednesday, December 24 through Friday, December 26 for the holiday. We wish you a warm, safe, and joyful celebration! 🎄✨
Regular operations will resume on Monday.

#SAS #Spectroscopy #HolidayClosing
December 23, 2025 at 3:09 PM
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🌟 Thank you to our 2025 Corporate Partners for supporting and advancing the spectroscopy community! See the list: https://loom.ly/ht3_2lc
Interested in partnering for 2026? Contact exdir@s-a-s.org

#SAS #Spectroscopy
December 22, 2025 at 3:06 PM
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New from Applied Spectroscopy!
High-Purity Strontium Carbonate Shows the Narrowest Peak Width of Raman Scattered Light
Read more: https://doi.org/10.1177/00037028251318757
#SAS #Spectroscopy #Raman #Spectrometer #resolution #symmetric #stretching #vibration #peak #laser
Abstract Raman microscopes are widely used in various fields and their spectral resolutions differ greatly depending on the system and optical components. Thus, it is important to evaluate the spectral resolution of Raman systems under measurement conditions. Although calcite is a crystal with a trigonal structure and its narrow peak at ∼1086 cm−1 has been used to evaluate the spectral resolution of Raman spectrometers, the peak width of calcite itself, ∼1.3 cm−1 at full width half-maximum (FWHM), is not negligible under high spectral resolution conditions. Because the calcite peak at ∼1086 cm−1 originates from symmetric stretching, which is a common vibration mode for carbonate salts, we examined strontium carbonate (SrCO3), barium carbonate (BaCO3), and lead carbonate (PbCO3) reagents to find a material having a narrower peak width than calcite. SrCO3, BaCO3, and PbCO3 peaks originating from symmetric stretching were observed at 1072, 1059, and 1054 cm−1, respectively, and their peak widths at FWHM (0.67, 0.92, and 1.09 cm−1, respectively) were narrower than that of calcite (1.36 cm−1). The narrow peak width of SrCO3 was strongly dependent on its purity, probably due to its high structural regularity, and the change in the peak width (FWHM) was only 0.12 cm−1 between 5 °C and 45 °C. Thus, we concluded that the high-purity SrCO3 peak at 1072 cm−1 was the narrowest peak of Raman scattering light under ambient conditions and is suitable for evaluating high spectral resolution for Raman spectrometers.
December 22, 2025 at 2:09 PM
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🎁 As the year ends, consider supporting the Society for Applied Spectroscopy. Your 501(c)(3) donation advances education, research & professional growth in our community. 💡 Check for employer matching! Give today: https://bit.ly/4on0wpY
#SAS #Spectroscopy #Donate
December 19, 2025 at 3:35 PM
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New from Applied Spectroscopy!
Determination of Laser-Induced Fluorescence Lifetimes Excited by Pulses of Comparable Duration
Read Open Access 🔓: https://doi.org/10.1177/00037028251332975
#SAS #Spectroscopy #Fluorescence #Lifetime #Phosphorescence #nanosecond #pulsed #laser
Abstract This paper presents a novel analytical technique for evaluating fluorescence lifetimes excited by a nanosecond pulsed laser using a linearized rate equation approach that accounts for the incident pulse temporal distribution, an equivalent instrument response function, and non-exponential fluorescence decay which limits the application of traditional fluorescence lifetime techniques in stand-off applications. The approach is applied to model the fluorescence of a variety of pharmaceutical powders and phosphorescing samples exhibiting non-exponential decay and compared to results obtained with the maximum entropy method. Fluorescence lifetimes are found to be 3–5  ns, typical for organic fluorescent powders, and phosphorescence lifetimes were on the order of hundreds of nanoseconds. The approach also shows potential for determining the composition of mixed samples and can be readily extended to model increasingly complex scenarios with additional fluorescing or phosphorescing components.
December 19, 2025 at 2:08 PM
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Congratulations to Dr. Geraldine Richmond, who was awarded the 2025 NY/NJ SAS Gold Medal Award at this year's Eastern Analytical Symposium in Plainsboro, NJ!

Learn more about Dr. Richmond and the award symposium that accompanied the award presentation here: https://loom.ly/fC_7ddA.
December 18, 2025 at 2:05 PM
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🎁 Give your team the gift of SAS membership! Support professional growth, collaboration & development in spectroscopy. Interested in bulk memberships? Contact exdir@s-a-s.org

#SAS #Spectroscopy #Membership
December 17, 2025 at 3:17 PM
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New from Applied Spectroscopy!
Deadliest Animals with the Thinnest Wings: Near-Infrared Properties of Tropical Mosquitoes
Read open access 🔓: https://doi.org/10.1177/00037028251341317
#SAS #Spectroscopy #NIR #mosquitoes #spectral #reflectance #remote #hyperspectral
Abstract Tropical mosquitoes transmit diseases like malaria, yellow fever, and Zika. Classifying mosquitoes by species, sex, age, and gravidity offers vital insights for assessing transmission risk and effective mitigations. Photonic monitoring for mosquito classification can be used in distributed sensors or lidars on longer ranges. However, a reflectance model and its parameters are lacking in the current literature. This study investigates mosquitoes of different species, sexes, age groups, and gravidity states, and reports metric pathlengths of wing chitin, body melanin, and water. We use hyperspectral push-broom imaging and laser multiplexing with a rotation stage to measure near-infrared spectra from different angles and develop simple models for spectral reflectance, including wing thickness and equivalent absorption path lengths for melanin and water. We demonstrate wing thickness of 174 (±1) nm – the thinnest wings reported to our knowledge. Water and melanin pathlengths are determined with ∼10 µm precision, and spectral models achieve adjusted R² values exceeding 95%. While mosquito aspect angle impacts the optical cross-section, it alters shortwave infrared spectra minimally (∼2%). These results demonstrate the potential for remote retrieval of micro- and nanoscopic mosquito features using spectral sensors and lidars irrespective of insect body orientation. Improved specificity of vector monitoring can be foreseen.
December 17, 2025 at 2:07 PM
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🏆 Nominations for the 2026 SAS Awards close Dec 31! Help honor excellence in spectroscopy by nominating a deserving colleague. Submit here: https://bit.ly/3M5zxSj

#SAS #Spectroscopy #Awards #DeadlineReminder
December 16, 2025 at 3:22 PM
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Our latest Early Career Interest Group member of the month is Adam J. Rish from Sentronic US Corp!

Learn more about ECIG here: https://loom.ly/zsOtowE

#SAS #spectroscopy #earlycareer
December 15, 2025 at 6:15 PM
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New from Applied Spectroscopy:
Multi-Angle Averaging Approach for Measuring the Coating Thickness on Thin Transparent Polymer Films
Read Open Access: https://doi.org/10.1177/00037028251334152
#SAS #Spectroscopy #InfraRed #FilmThickness #reflection #nanometer #interference #inline #measurement
Abstract Polymer films with a thickness in the two-digit micrometer range are coated with nanometer-thin oxide layers in roll-to-roll coating systems. The coating improves the properties of the film, such as gas or water permeation. Maintaining a sufficiently large coating thickness is crucial to ensure its barrier function; thus, inline quality control of the thickness is indispensable. For this purpose, we have developed a sensing principle that addresses specific absorption bands of the coating via a reflection measurement in the infrared spectral range. However, for thin and weakly absorbing polymer substrates, light is reflected not only by the coating and the surface of the polymer. Partly it is also transmitted and reflected by the backside of the film, leading to interference effects that significantly affect the measurement signal. As industrial films vary in thickness by several percent and their exact values are unknown, determining the thickness of an oxide coating is hindered. In this paper, we demonstrate an approach for measuring coating thickness on such varying polymer films by averaging the interferences obtained at multiple angles of incidence. Calculations and measurements on industrial film samples indicate the effectiveness of our approach. It produces results with ±2 nm precision and ±5 nm accuracy for a thickness in the range of 5–100 nm. Furthermore, we discuss a possible implementation of this approach in an inline measurement system by fulfilling its requirements, for example, versatility and compactness.
December 15, 2025 at 2:07 PM
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🕎 Wishing a bright and joyful Hanukkah to all who celebrate! May the season bring light, peace, and warmth to you and your loved ones.

#SAS #Hanukkah #FestivalOfLights
December 14, 2025 at 2:24 PM
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New from Applied Spectroscopy!
Enhanced Carbon Dioxide Uptake in Drilled Hollow Core Fibers for Raman Spectroscopy
Read more: https://doi.org/10.1177/00037028251329418
#SAS #Spectroscopy #Raman #RamanSpectroscopy #CarbonDioxide
Abstract Fiber-based Raman spectroscopy enhances the Raman signal by maximizing the overlap of the optical field and the gas species. However, filling the hollow-core fiber (HCF) with gas requires time that is dependent on the fiber core diameter, fiber length, and pressure of the gas. At ambient pressure, the fiber gas uptake is driven by diffusion into the fiber ends, severely limiting the response time of the system. By laser drilling access holes to the core along the length of the fiber, the uptake time of the gas is reduced, improving the system response time. In this work, we study the carbon dioxide (CO2) sensor dynamics based on Raman signal intensity generated in HCFs. The signal intensity versus gas concentration is characterized by controlling the CO2 concentration in the surrounding environment of the fiber. Next, we characterize the gas uptake time in HCFs as a function of fiber length. Finally, we optimize the access hole configuration along the fiber, demonstrating reduced sensor uptake time by a factor of three.
December 12, 2025 at 2:07 PM
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🌟 Thank you to our amazing volunteer leaders for a great year! Your dedication drives SAS forward, and we’re excited for what’s ahead. Want to get involved? Contact exdir@s-a-s.org
#SAS #Spectroscopy #Volunteers #Community
December 11, 2025 at 3:05 PM
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New from Applied Spectroscopy!
Classification of #Waxy #Maize Kernels Using Single #Kernel Near-Infrared Reflectance #Spectroscopy

Read more: https://doi.org/10.1177/00037028251349556
#SAS #NIR #reflectance #corn #nondestructive
Image consists of a picture of the sorting instrument, image of two kernels (waxy and wild type), and a scheme of the process: maize kernels -> near-infrared reflectance (NIR) Spectroscopy -> linear discriminant analysis (LDA) -> waxy maize prediction equation -> images of training and validation sets -> Waxy maize kernel validation prediction accuracy: 88% -> NIR single kernel waxy sorting
December 10, 2025 at 2:05 PM
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💼 Looking for your next opportunity in spectroscopy or analytical science? Explore the latest openings on the SAS Career Postings page! Whether you're advancing your career or looking for a new direction, great opportunities await.
December 9, 2025 at 1:30 PM
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New from Applied Spectroscopy!
Combining a #Multispectral Camera and #Spectrometer for #Spectral Data Acquisition and #Noninvasive Blood Composition Measurement

#SAS #Spectroscopy #bloodanalysis #hyperspectral
Image of finger clip with apertures for light, hyperspectral camera (HSC) and spectrometer. A scheme, indicating that the computer analyzes the combined signals from the HSC and spectrometer. A graph, indicating a good correlation (k=0.92) between the true and predicted values of HGB-Model 3 in blood. Text Box: Conclusion: Spectrometers have low amplitude resolution and accuracy, while HSPs suffer from limited number of wavelength channels. To solve this, we propose a method of acquiring spectrometer data combined with HSP and modelling the data. This combines the advantages of both, and effectively improves the accuracy of the non-invasive blood components measurements.
December 8, 2025 at 4:09 PM
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🎁 As the year ends, consider supporting the Society for Applied Spectroscopy, a 501(c)(3) nonprofit. Your gift fuels education, innovation & opportunities in our community. 💡 Check for employer matching! Donate: https://bit.ly/4on0wpY
#SAS #Spectroscopy #Giving
December 5, 2025 at 3:14 PM
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New from Applied Spectroscopy!
Detection of β-Hydroxybutyric Acid Based on a Fluorescent Probe of Lanthanide Complexes
#SAS #Spectroscopy #UVVis #fluorescence #diabetic #ketoacidosis #diabetes #mellitus
Left part shows Tb3+ ions foeming somplex with 4-MBA and two water molecules. The water molecules are exchanged with two beta-Hb molecules. The complexes are excited by 317 nm and emit at 539 nm. The right part shows the emission intensity (at 530-550 nm) is linear in the range of 4 to 55 uM of beta-Hb (r^2=0.998).
December 5, 2025 at 1:55 PM
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🎉 Thank you to our 2025 Applied Spectroscopy Practica Sponsors! We appreciate your support in advancing spectroscopy. See this year’s sponsors: https://loom.ly/EUoPHmc
Interested in sponsoring 2026? Contact exdir@s-a-s.org
#SAS #Spectroscopy #Practica
December 4, 2025 at 6:14 PM
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New from Applied Spectroscopy!

In-Line #Raman #Spectroscopy for #Polymorph Monitoring During Continuous #Crystallization
Read more at: https://doi.org/10.1177/00037028251344294

#SAS #RamanSpectroscopy #inline #SocApplSp
The left panel shows a continuous reactor with a Raman probe monitoring the reaction. The right pane shows 2nd derivative of Raman spectra (1580-1720 cm^-1) of Form A, Form C and series of in-line polymorphs. The 1695-1705 cm^-1 range is grayed, since Form A has an unique peak there.
December 3, 2025 at 4:30 PM