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Scientific Posters
Turning analytical expertise into scientific insights.
Sharing scientific insights beyond the laboratory.
Sameness Assessment of Peptide Therapeutics
Using 1D & 2D NMR spectroscopy
Peptide drugs, including GLP-1 analogues, are structurally complex molecules whose biological activity and quality are closely dependent on their higher-order structure (HOS), which represents a critical quality attribute. Regulatory pathways, such as abbreviated new drug applications (ANDAs) and biosimilar frameworks, require comprehensive evidence demonstrating structural and functional similarity to the reference product.
This includes the assessment of equivalent primary, secondary, and tertiary structures, as well as oligomerization, product-related impurities and process-related variants. Reliable analytical strategies are therefore essential to demonstrate structural comparability and ensure consistent product quality.
Adulteration of Used Cooking Oils
An NMR method for the detection of fresh and palm oil in used cooking oils
Used cooking oils (UCOs) intended for biodiesel production can be adulterated with fresh palm oil (PO), potentially resulting in substantial losses of public funds through EU subsidy programs. Conventional lipid analysis techniques, such as HPLC and GC, have limited capabilities when it comes to reliably detecting the addition of fresh PO after the oil has been used for cooking.
13C-NMR spectroscopy can distinguish between UCOs with and without added PO by characterizing differences in their fatty acid distributions. In addition, 1H-NMR spectroscopy enables the detection of fresh, unrefined PO based on specific heat-sensitive compounds, with detection possible at concentrations as low as approx. 2% (w/w).
Together, these complementary NMR approaches provide a rapid and effective strategy for identifying the adulteration of UCOs with fresh PO.
The (q)NMR-Cocktail
A recipe for lithium-ion-battery analysis focusing the recycling process
The NMR cocktail allows a comprehensive look into battery samples. In routine analysis, 1H- NMR and 13C-NMR spectra are the most widely used, e.g. to easily quantify the purity and mixing ratio of the solvents in liquid electrolytes with a measurement < 5min using 1H-qNMR. However, analysis is not limited to these two nuclei. Especially for lithium-ion battery research, NMR-active nuclei such as 7Li, 19F and 31P are of great interest to gain a comprehensive picture of the sample. Therefore, lithium salts like LiPF6 are to be investigated with the “NMR cocktail” of measurements using 1H-, 7Li-, 13C-, 19F- and 31P-NMR to get the full qualitative and quantitative picture.
31P-NMR Krill and PS Methods
Developed at Spectral Service AG, implemented into USP methods
NMR methods are particularly well suited for use as USP methods because they are inherently quantitative, highly reproducible and require minimal method-specific calibration. NMR signal intensities are directly proportional to the number of nuclei contributing to a signal, enabling accurate quantification, particularly when an internal standard is involved, without the need for compound-specific response factors.
The United States Pharmacopeia (USP) has adopted a 31P-NMR method for the analysis of krill oil that was originally developed at Spectral Service AG. Over time, Spectral Service AG has further optimized the method, improving its efficiency and adapting it for routine analytical applications. A corresponding method for the analysis of phosphatidylserine (PS)-enriched lecithins is currently being integrated into the USP as well.
The integration of NMR methods into the USP ensures alignment with international standards, supports the use of validated analytical procedures, and facilitates compliance with applicable regulatory requirements.
The PGStE Pulse Sequence
Use in NMR spectroscopy for characterization of biological macromolecules
Biological macromolecules, such as glycosaminoglycans, often exhibit highly complex matrices that can hinder their analytical characterization due to the presence of various components and impurities. Even purification procedures have limitations in terms of extraction efficiency and cannot exclude signal overlapping in NMR spectra.
To address these challenges, pulsed gradient stimulated echo (PGStE) NMR spectroscopy can be applied to selectively suppress signals from small molecules while preserving the analyte signal to a large extent. When combined with 1H-NMR spectroscopy, this approach therefore enables improved characterization of macromolecules in complex sample matrices.
Determination of Peroxide Value in Microalgae Oil by 19F-NMR
Method comparison
Traditionally, the peroxide value (PV) is determined by nonspecific titration. However, the interpretation of titration results for microalgae oil is limited due to its complex matrix, necessitating an analytical method that is better suited to this type of sample. In microalgae oil, the direct quantification of peroxides and the subsequent calculation of the PV using 1H-NMR spectroscopy are particularly useful for monitoring oxidation from the early to intermediate stages through to more advanced stages, when secondary oxidation products begin to form. During the earliest stages of oxidation, however, the sensitivity of 1H-NMR is not optimal. The high content of long-chain polyunsaturated fatty acids in microalgae oil results in the formation of a broad range of hydroperoxides during oxidation, which is reflected by numerous small peroxide signals in the 1H-NMR spectrum. To address this limitation, a more sensitive analytical method based on 19F-NMR spectroscopy is presented, with the aim of developing a suitable approach for future quality control applications.
Quality Control of Cannabis by NMR
How to gain a holistic overview of your material with one technique & various approaches
The partial legalization of cannabis in Germany and other countries, together with its increasingly widespread use for medical applications, has heightened the need for a robust and reliable quality control. NMR spectroscopy enables the direct analysis of cannabinoids and terpenes in complex samples without prior separation and the need for reference standards.
With short measurement times, NMR provides not only accurate quantitative results but also comprehensive structural information, enabling the identification of both known and previously unknown compounds. These capabilities highlight one of the key advantages of NMR: its holistic, non-targeted analytical approach. This makes NMR particularly well suited for comprehensive quality control and regulatory applications in accordance with GMP requirements.
Development of an NMR-based Method for the Analysis of PFAS
Investigating the “forever chemicals”
PFAS are persistent, bioaccumulative, and potentially toxic substances that have been widely used in industrial and consumer products. After decades of extensive use, including in applications such as non-stick coatings for cookware, it has become clear that PFAS do not degrade in the environment. These so-called “forever chemicals” therefore pose significant challenges to both environmental and human health.
Current standard analytical methods, such as LC-MS, face limitations related to the availability of reference standards, structural characterization, and comprehensive quantification. This work therefore evaluates 19F-NMR spectroscopy as a complementary analytical approach for the detection, characterization, and quantification of PFAS.
13C-Isotope Analysis with NMR
Potential challenges and improvements
In food products, the origin of ingredients is often used as a marketing claim, with terms as “natural flavor” suggesting a specific source or production method. However, when molecules from different origins are chemically identical, how can their claimed origin be reliably verified? A popular example for that issue is vanillin. It can either be synthesized or obtained from the vanilla bean which is more cost-intensive.
To meet this question of origin, isotope analysis can help. Isotope analysis is the study of proportions of certain isotopes in a molecule, for example 12C and 13C. In isotope analysis different signatures can be obtained depending on the origin. NMR allows to look at this isotopic signature for each position within a molecule enabling a differentiating.
NMR Investigation of Breast Implants
Analysis of the silicone structure using 1H-NMR
In 2010, French authorities prohibited the sale and implantation of Poly Implant Prothèse (PIP) breast implants. According to publications by the National Health Service (NHS) and the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR), these implants were associated with a higher risk of rupture compared with standard breast implants.
Breast implants are generally manufactured using medical-grade silicone elastomers, which are designed to be resistant to tearing and leakage. In contrast, PIP implants were found to contain non-medical-grade industrial silicone that had not been certified for medical use and did not provide the same level of protection against leakage.
To distinguish between the different types of silicone used as implant fillings, a test method based on 1H-NMR spectroscopy was established.
