FT-IR Spectroscopy Provides Insights into Green Synthesis and Stabilization of Nanoparticles

Currently, green analytical chemistry (GAC) methods are being sought out in order to make laboratory work more sustainable. GAC methods are designed to reduce or completely eliminate the use of toxic chemicals and reagents in the analysis process (1). A recent review article published in Molecules explores this topic. In the review article written by researchers from Maria Curie-Skłodowska University in Lublin, Poland, the research team examines the growing role of Fourier transform infrared (FT-IR) spectroscopy in deciphering the complex chemical processes that underpin nanoparticle formation, stabilization, and application (2).

FT-IR spectroscopy has become more widely used in analyzing nanoparticles synthesized through environmentally friendly, or green, methods (1,2). Although FT-IR spectroscopy has long been a universal method for probing the internal molecular structures of materials by analyzing atomic vibrations and rotations, its importance in nanotechnology has surged in recent years. This review article explores how functional groups observed in FT-IR spectra are responsible for reducing, capping, and stabilizing nanoparticles, which are crucial steps that ensure these particles retain their desired properties for practical applications (1).

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Why is green synthesis being used more often in nanomaterials research?

Green synthesis is a new sustainability method that does not use hazardous chemicals. Instead, it employs plant extracts, microorganisms, and other eco-friendly reducing agents, and it is being used more often in nanomaterials research as of late (2). Green synthesis often involves functional groups such as hydroxyl, carboxyl, amine, and carbonyl, all of which play distinctive roles in reducing metal ions and preventing nanoparticles from aggregating (2). What FT-IR spectroscopy allows researchers to do is identify these groups through characteristic absorption peaks, effectively verifying the success of nanoparticle synthesis (2).

FT-IR analysis is designed to provide scientists a chemical fingerprint for two purposes. It helps confirm nanoparticle formation and also reveals the biomolecules involved in stabilizing structures (2), which is vital for applications ranging from targeted drug delivery systems to bioremediation technologies, where nanoparticle stability and reactivity are paramount (2).

Another important topic this review article covers is the challenges scientists face when analyzing FT-IR spectra in nanoparticle studies. One widely used method, the transmission spectroscopy (TS) technique, offers high-quality spectra with strong signal-to-noise ratios (2). However, TS requires samples to be pressed into potassium bromide (KBr) pellets, which is an issue. This process is a problem because it can distort delicate structures, introduce moisture-related interference, and risk contamination (2). For opaque or plant-derived samples, the technique becomes particularly problematic because of strong infrared (IR) absorption (2).

What are the advantages of FT-IR spectroscopy?

FT-IR spectroscopy has numerous advantages when used in this field. It can conduct non-destructive testing, which means that any sample under study remains intact (2). FT-IR spectroscopy also has high sensitivity and the ability to characterize surface chemistry and monitor reactions in real time. These features have made FT-IR indispensable in advancing nanotechnology, particularly as researchers strive to design nanoparticles with precise shapes, sizes, and surface properties for specialized uses (2).

What are the key takeaways from this study?

Researchers should note that nanotechnology is a growing field, and it is now being applied in more industries and application areas than ever before. From medicine to environmental analysis, nanoparticles are being employed as new analytical methods (2). As a result, understanding the chemical underpinnings of nanoparticle synthesis is essential to ensuring safety, reproducibility, and functionality in real-world applications.

This review article helps provide an overview of these chemical underpinnings in nanoparticle synthesis. By consolidating scattered findings into a single comprehensive source, this review article serves as a useful tool for researchers worldwide who are navigating the complex chemistry of green-synthesized nanoparticles (2).

References

1. Kaya, S. I.; Cetinkaya, A.; Ozkan, S. A. Green Analytical Chemistry Approaches on Environmental Analysis. Trends Environ. Anal. Chem. 2022, 33, e00157. DOI: 10.1016/j.teac.2022.e00157
2. Pasieczna-Patkowska, S.; Cichy, M.; Flieger, J. Application of Fourier Transform Infrared (FTIR) Spectroscopy in Characterization of Green Synthesized Nanoparticles. Molecules 2025, 30 (3), 684. DOI: 10.3390/molecules30030684