August 25th 2025
This tutorial contrasts classical analytical error propagation with modern Bayesian and resampling approaches, including bootstrapping and jackknifing. Uncertainty estimation in multivariate calibration remains an unsolved problem in spectroscopy, as traditional, Bayesian, and resampling approaches yield differing error bars for chemometric models like PLS and PCR, highlighting the need for deeper theoretical and practical solutions.
The case studies presented here successfully demonstrate the use of inline Raman spectroscopic analysis to estimate solvent content during the solvent exchange and distillation operations in the synthesis of active pharmaceutical ingredients.
Investigating Food Purity Using Raman Spectroscopy Combined with Machine Learning
February 11th 2022Determining the quality of the food we consume is important not just for reasons of safety, but for verifying authenticity as well. Changmou Xu, a Research Associate Professor at the University of Nebraska-Lincoln (UNL), and his colleagues have been exploring methods for food analysis that are rapid but do not harm the environment or the analysts.
Rapid Detection and Quantification of Plant Innate Immunity Response Using Raman Spectroscopy
February 10th 2022As global food supplies and security have been challenged by water scarcity and climate variations, the expected increase in food demand will require a corresponding increase in crop productivity and disruptive improvements in agricultural production systems, including implementing strategies to mitigate the degradation of crop yield caused by plant diseases. Several groups have explored the use of Raman spectroscopy for rapid diagnosis of such diseases.
Investigating Forensics Applications of Raman Spectroscopy, ATR FT-IR, and Chemometrics
December 10th 2021As forensic analysis continues to advance, such as in the understanding of source identification and analysis of trace quantities of bodily fluids, spectroscopic techniques and machine learning are playing a significant role. Igor K. Lednev, a chemistry professor at the University at Albany, SUNY, in Albany, New York, has been working in this field with his team. The analytical methods currently under investigation include Raman spectroscopy, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy, and advanced chemometric classification and analysis methods. We recently interviewed him about his work.
Investigating Protein Receptors and Other Biomolecules Using SERS and TERS
September 2nd 2021Zac Schultz of The Ohio State University and his team used tip-enhanced Raman spectroscopy (TERS) and surface-enhanced Raman spectroscopy (SERS) with gold nanostars to investigate chemical reactions involved in protein–ligand binding. He recently spoke with Spectroscopy about his findings.
Exploring Neurochemistry Using Raman Spectroscopy
September 2nd 2021Bhavya Sharma is the winner of the 2021 Emerging Leader in Molecular Spectroscopy Award. We recently interviewed her about her work conducting research to detect active and important biomolecules related to hormone regulation, neurological health, and disease diagnosis.
Recording the Raman Spectrum of a Single Molecule
September 2nd 2021Analytical chemists are continually striving to advance techniques to make it possible to observe and measure matter and processes at smaller and smaller scales. Professor Vartkess Ara Apkarian and his team at the University of California, Irvine have made a significant breakthrough in this quest: They have recorded the Raman spectrum of a single azobenzene thiol molecule. The approach, which breaks common tenets about surface-enhanced Raman scattering/spectroscopy (SERS) and tip-enhanced Raman spectroscopy (TERS), involved imaging an isolated azobenzene thiol molecule on an atomically flat gold surface, then picking it up and recording its Raman spectrum using an electrochemically etched silver tip, in an ultrahigh vacuum cryogenic scanning tunneling microscope. For the resulting paper detailing the effort [1], Apkarian and his associates are the 2021 recipients of the William F. Meggers Award, given annually by the Society for Applied Spectroscopy to the authors of the outstanding paper appearing in the journal Applied Spectroscopy. We spoke to Apkarian about this research, and what being awarded this honor means to him and his team. This interview is part of an ongoing series with the winners of awards that are presented at the annual SciX conference. The award will be presented to Apkarian at this fall’s event, which will be held in person in Providence, Rhode Island, September 28–October 1.
An Adventure with Light and Reflections on Science
September 2nd 2021Working at the frontiers of biotechnology, fiberoptics, lasers technique, and molecular spectroscopy, Tuan Vo-Dinh of Duke University has developed multiple sensor technologies for medical research and diagnostics. Throughout this work, Vo-Dinh and his research colleagues have brought spectroscopy to biomedical applications. In this second recent interview, Vo-Dinh talks about his research work and philosophy.
An increasing number of antibiotic residue problems in food have emerged around the world. We examine how SERS is used to identify antibiotic residues in chicken, focusing on doxycycline hydrochloride and tylosin.
Raman Spectroscopy: A Key Technique in Investigating Carbon-Based Materials
August 1st 2021This article explains the key steps of using Raman technology to investigate carbon and carbon-based materials—such as carbon nanotubes, graphene, and carbon fibers and composites—as well as the process of analyzing the spectra.
Using confocal Raman imaging and other advanced measurement techniques, we study the localized strain characteristics of tungsten diselenide (WSe2), an important nanomaterial used for optoelectronic device applications.