Top 10 Spectroscopy Articles of the Month: Highlights in Interpretive Infrared, AI, Raman Protein Analysis, and Analytical Biology

TOP 10 ARTICLES OF THE MONTH showing the mysteries of spectra in optical physics © Sekai - stock.adobe.com

The following articles are the 10 most accessed digital object identifier (DOI) manuscripts from Spectroscopy for December 2024. Each article has been selected based on the number of successful accesses by readers, showcasing key developments and insights in spectroscopy and chromatography. Spectroscopy covers the main topics of electronic spectroscopy, vibrational spectroscopy, magnetic resonance, imaging techniques, atomic spectroscopy, and data analysis and integration.

This month we highlight articles from the ever popular Spectroscopy columns IR Spectral Interpretation Workshop, Chemometrics in Spectroscopy, Molecular Spectroscopy Workbench, and a Feature Article on Analytical Biology. We hope you enjoy looking through the most accessed DOI registered technical articles from December.

The Infrared Spectra of Polymers III: Hydrocarbon Polymers
This article focuses on the infrared (IR) spectra of hydrocarbon polymers, particularly polypropylene and polystyrene. The article explores the unique spectral features of these materials, discussing how IR spectroscopy helps distinguish between them based on specific absorption bands. The article provides an in-depth analysis of the spectra, highlighting functional groups and bond types involved, serving as a practical review of IR spectral interpretation for polymer characterization (1).

The Infrared Spectra of Polymers II: Polyethylene
This article continues the discussion of polyethylene (PE), a widely used polymer, with a focus on its diverse physical and spectroscopic properties. It examines how variations in the synthesis of PE lead to differences in these properties, particularly the phenomenon of crystalline splitting and the role of CH₂ rocking peaks. This installment provides further insight into the spectral features of PE, enhancing the understanding of how IR spectroscopy can be applied to analyze polymer materials (2) .

Artificial Intelligence in Analytical Spectroscopy, Part II: Examples in Spectroscopy
In this second part of a two-part series, this article delves into the applications of artificial intelligence (AI) and machine learning (ML) in electronic and vibrational spectroscopy. The article explores the use of AI and ML in various spectroscopic techniques, such as Raman, FT-IR, NIR, and UV-Vis, demonstrating how deep learning and advanced algorithms can be applied to solve complex analytical problems. The article offers a broad sampling of the current research and potential future directions for AI in analytical spectroscopy (3).

Infrared Spectroscopy of Polymers, VIII: Polyesters and the Rule of Three
Here the author provides a detailed review of polyesters, focusing on the spectroscopy of the ester functional group and its analysis in various polyester samples, including polyethylene terephthalate (PET). The article introduces the “Rule of Three,” a guideline for interpreting spectra of carbonyl-containing polymers. The discussion includes an analysis of ester-related absorption bands and their significance in the identification and characterization of polyesters, which are crucial materials in both industrial and consumer products (4).

Interpretation of Raman Spectrum of Proteins
The interpretation of Raman spectra for proteins is reviewed in this article, emphasizing the importance of understanding band assignments for structural analysis. The article connects Raman spectroscopy to the study of protein functionality, referencing recent work on protein conformation and stability. The article discusses how Raman spectra provide insights into protein structure, making it a valuable tool in biochemistry and molecular biology research (5).

Infrared Spectroscopy of Polymers XIII: Polyurethanes
This series continues to discuss nitrogen-containing polymers by examining polyurethanes, which are used in a variety of products such as foam rubber and coatings. The article compares the IR spectra of polyurethanes to polyamides due to similarities in their molecular structures, particularly the presence of C=O and N-H bonds. The article provides an in-depth look at the spectral features of polyurethanes and the role of IR spectroscopy in analyzing these materials (6).

Infrared Spectroscopy of Polymers, IX: Pendant Ester Polymers and Polycarbonates
In this article the spectra of pendant ester polymers and polycarbonates are explored, highlighting cellulose acetate as an example of a carbohydrate-derived ester polymer. The article also covers the spectra of polycarbonates, such as Lexan, an important material used in windows and automotive parts. Detailed spectral analysis is provided, illustrating the characteristic absorption bands of ester and carbonate functional groups in these polymers (7).

Artificial Intelligence in Analytical Spectroscopy, Part I: Basic Concepts and Discussion
The authors introduce the concept of artificial intelligence (AI) and its relationship with machine learning (ML) and chemometrics in the context of analytical spectroscopy. This article lays the foundation for the second part of the series by discussing the basic principles of AI, its applications in spectroscopy, and the potential benefits and challenges of integrating AI with traditional chemometric methods. It sets the stage for a deeper exploration of AI’s impact on spectroscopic analysis (8).

Analytical Biology: An Emerging Discipline for the Future
The emerging discipline of analytical biology is explored in this feature article, which combines physics, biology, and chemistry to provide a more holistic view of biological phenomena. The article highlights the growing interest in interdisciplinary research, particularly the application of Raman spectroscopy in biological and medical fields. The authors discuss recent advancements in laser technology and how they have enabled the application of Raman spectroscopy to live cells, opening new frontiers in cell biology and medical diagnostics (9).

The Infrared Spectra of Polymers V: Epoxies
This column shifts focus to epoxies, a crucial class of polymers with C–O bonds that are widely used as adhesives. The article examines the IR spectra of epoxies, exploring their functional groups and reaction mechanisms. It includes a discussion of epoxide groups and their transformation into useful materials. This column also provides a solution to the previous IR Spectral Interpretation Workshop, reinforcing the learning process for readers (10).

References

(1) Smith, B. C. The Infrared Spectra of Polymers III: Hydrocarbon Polymers. Spectroscopy 2021, 36 (11), 22–25. DOI: 10.56530/spectroscopy.mh7872q7.

(2) Smith, B. C. The Infrared Spectra of Polymers II: Polyethylene. Spectroscopy 2021, 36 (9), 24–29. DOI: 10.56530/spectroscopy.xp7081p7.

(3) Workman, J., Jr.; Mark, H. Artificial Intelligence in Analytical Spectroscopy, Part II: Examples in Spectroscopy. Spectroscopy 2023, 38 (6), 10–15. DOI: 10.56530/spectroscopy.js8781e3.

(4) Smith, B. C. Infrared Spectroscopy of Polymers, VIII: Polyesters and the Rule of Three. Spectroscopy 2022, 37 (10), 25–28. DOI: 10.56530/spectroscopy.ta9383e3.

(5) Adar, F. Interpretation of Raman Spectrum of Proteins. Spectroscopy 2022, 37 (2), 9–13, 25. DOI: 10.56530/spectroscopy.lo2270l5.

(6) Smith, B. C. Infrared Spectroscopy of Polymers XIII: Polyurethanes. Spectroscopy 2023, 38 (7), 14–16. DOI: 10.56530/spectroscopy.fn3378a3.

(7) Smith, B. C. Infrared Spectroscopy of Polymers, IX: Pendant Ester Polymers and Polycarbonates. Spectroscopy 2022, 37 (11), 16–19, 31. DOI: 10.56530/spectroscopy.xn9369p8.

(8) Workman, J., Jr.; Mark, H. Artificial Intelligence in Analytical Spectroscopy, Part I: Basic Concepts and Discussion. Spectroscopy 2023, 38 (2), 13–22. DOI: 10.56530/spectroscopy.og4284z8.

(9) Li, M.; Fujita, K. Analytical Biology: An Emerging Discipline for the Future. Spectroscopy 2024, 39 (2), 28–31. DOI: 10.56530/spectroscopy.ui9669c4.

(10) Smith, B. C. The Infrared Spectra of Polymers V: Epoxies. Spectroscopy 2022, 37 (3), 17–19. DOI: 10.56530/spectroscopy.mg2473z4.