Article
Spectroscopy
David A. Price, Poornima Wedamulla, Tayler D. Hill, Taylor M. Loth, Sean D. Moran
Summary: Guanine-rich nucleic acid sequences can form G-quadruplex structures with different characteristics. By comparing the polarization dependences of cross-peaks in two-dimensional infrared (2D IR) spectra, parallel-stranded and antiparallel-stranded G-quadruplexes can be distinguished. This study reveals key features of a Bcl-2 proximal promoter and demonstrates the convenience of using 2D IR spectroscopy for analyzing G-quadruplex structures.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Spectroscopy
Jesvin Joseph, Lukas Spantzel, Maryam Ali, Dijo Moonnukandathil Joseph, Sebastian Unger, Katharina Reglinski, Christoph Krafft, Anne-Dorothea Mueller, Christian Eggeling, Rainer Heintzmann, Michael Boersch, Adrian T. Press, Daniela Taeuber
Summary: The recently developed PiF-IR microscopy offers high spectral resolution, surface sensitivity, and nanoscale spatial resolution. It has the potential to characterize cellular structures at the single-molecule level. PiF-IR was applied to polymerized F-Actin samples and mouse liver tissue, showing variations in contrast. However, interpreting and validating the data is challenging due to the presence of other proteins and the unique spatial resolution of PiF-IR.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2024)
Article
Chemistry, Analytical
Zhongyue Guo, Yeran Bai, Meng Zhang, Lu Lan, Ji-Xin Cheng
Summary: Antimicrobial resistance poses a major threat to global health and economics, necessitating rapid AST methods. We introduce a rapid AST method based on wide-field mid-infrared photothermal imaging, capable of metabolic imaging for hundreds of bacteria at single-cell resolution within seconds. This method enables probing of perturbed microbial protein synthesis within 1 hour after antibiotic treatment in E. coli cells, providing insights into antibiotic susceptibility.
ANALYTICAL CHEMISTRY
(2023)
Article
Biochemical Research Methods
K. Srivastava, N. D. Boyle, G. T. Flaman, B. Ramaswami, A. van den Berg, W. van der Stam, I. J. Burgess, M. Odijk
Summary: Determining kinetic reaction parameters is crucial in chemical reaction engineering. Existing methods lack sufficient spatiotemporal resolution. This study demonstrates the use of a custom-designed single-bounce ATR-integrated microfluidic reactor, along with synchrotron IR radiation, to achieve in situ monitoring of chemical reactions with high spatiotemporal resolution.
Article
Crystallography
Kende Attila Beres, Zoltan Homonnay, Laura Bereczki, Zsolt Durvanger, Vladimir M. Petrusevski, Attila Farkas, Laszlo Kotai
Summary: Three octahedral iron(III) nitrate complexes with dimethylated urea ligand isomers were synthesized and characterized. The complexes were studied using single crystal X-ray diffraction, IR, Raman, and UV-Vis methods. The ligands in compounds 1 and 3 coordinate to the central Fe-III ion in an octahedral geometry and form propeller-like arrangements. The complexes exhibit helical chirality and have different hydrogen bond formations on each side of the complex cations. Compound 2 forms layers of [Fe(N,N-dimethylurea)(4)(H2O)(2)](3+) cations connected by NO3- ions, and the nitrate ions form hydrogen bonding with different characteristics.
Article
Chemistry, Physical
P. Gasse, T. Stensitzki, Y. Mai-Linde, T. Linker, H. M. Mueller-Werkmeister
Summary: Researchers successfully used thiocyanate (SCN) as a label to investigate the infrared and 2D-IR spectra of glucose. The study demonstrates that the concept of using site-specific vibrational reporter groups can be applied to carbohydrates, expanding the biophysical studies with 2D-IR spectroscopy to the field of glycoscience.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Olena Zavorotynska, Magnus H. Sorby, Jenny G. Vitillo, Stefano Deledda, Christoph Frommen, Bjorn C. Hauback
Summary: Metal hydroborates are versatile materials with interesting properties related to energy storage and cation conductivity. CsB3H8 undergoes two phase transitions before decomposition, transforming from an orthorhombic room temperature phase to a new phase at 73 degrees C, and then to a face-centered cubic phase at 88 degrees C. Studies on these phase transitions and decomposition pathways using various techniques provide insights into the properties and potential applications of CsB3H8.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Biochemistry & Molecular Biology
Friedrich Kremer, Wycliffe Kiprop Kipnusu, Martin Fraenzl
Summary: The limitations of the Debye approximation in the theory of orientation polarization and dielectric relaxation are discussed, and specific parameters of molecular absorption are measured using infrared spectroscopy, interpreting the observed effects as caused by orientation polarization of the OH and CH2 moieties.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Biotechnology & Applied Microbiology
Young Hoon Oh, Matthew L. Becker, Kerri M. Mendola, Leila H. Choe, Lie Min, Kelvin H. H. Lee, Yinges Yigzaw, Alexander Seay, Jerome Bill, Xuanwen Li, David J. Roush, Steven M. Cramer, Stefano Menegatti, Abraham M. Lenhoff
Summary: In the production of biopharmaceuticals, the presence of residual host-cell proteins (HCPs) is a critical quality concern. Measurements on seven monoclonal antibody (mAb) processes revealed that HCP aggregates, not necessarily derived from chromatin, are important factors in the persistence of HCPs. These aggregates can also interfere with accurate detection of HCPs using proteomics methods. The study also highlights the difficulty in removing certain HCPs due to their functional complementarity to the biopharmaceutical product.
BIOTECHNOLOGY AND BIOENGINEERING
(2023)
Article
Chemistry, Physical
Ngaatendwe B. C. Pfukwa, Marina Rautenbach, Neil T. Hunt, Olufemi O. Olaoye, Vikas Kumar, Anthony W. Parker, Lucy Minnes, Pieter H. Neethling
Summary: We investigated the structure of Gramicidin S (GS) in a model membrane environment using 1D and 2D IR spectroscopy. Through analysis of IR spectral changes, we observed disruption of aggregates/oligomers and structural changes in the concentrated GS solution. Two melting transition temperatures were identified, indicating the disassembly of GS aggregates/oligomers and the change in hydrogen bonding patterns. This study provides insights into understanding GS structure and developing GS analogues with enhanced bioactivity.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Instruments & Instrumentation
Stephane Chevalier, Jean-Noel Tourvieille, Alain Sommier, Jean-Christophe Batsale, Bruno Beccard, Christophe Pradere
Summary: The technical note presents an advanced thermospectroscopic imager that combines FT-IR spectrometer and thermal camera technologies to image thermal emission and multispectral absorbance fields rapidly. The instrument demonstrates high efficiency and accuracy in processing and measuring, showcasing its potential for studying fast transient thermal and chemical phenomena with improved spectral resolution.
APPLIED SPECTROSCOPY
(2021)
Review
Instruments & Instrumentation
Malik M. Gafurov, Kamil Sh. Rabadanov
Summary: This review summarizes the literature information on techniques and methods for high-temperature spectroscopic measurements of molten electrolytes, including various spectroscopic techniques and the design of corresponding optical heating cells.
APPLIED SPECTROSCOPY REVIEWS
(2023)
Review
Chemistry, Analytical
Maria Chiara Sportelli, Christine Kranz, Boris Mizaikoff, Nicola Ciof
Summary: Biofilms are a major cause of health and environmental issues, with bacteria in biofilms showing greater resistance to biocides. Spectroscopic techniques play a crucial role in understanding biofilm formation. This review discusses recent progress and advantages/disadvantages of spectroscopic approaches for studying biofilms.
ANALYTICA CHIMICA ACTA
(2022)
Review
Biochemistry & Molecular Biology
Marco Pinto Corujo, Vivian Lindo, Nikola Chmel, Alison Rodger
Summary: In this study, CD, IR, and Raman spectroscopies were applied to characterize antibody PTMs, showing that secondary structure remained the same after treatments and stability was affected by modifications. Raman and IR analysis detected differences between reference and deglycosylated proteins, indicating the presence of other PTMs.
CURRENT PROTEIN & PEPTIDE SCIENCE
(2021)
Review
Instruments & Instrumentation
Stephanie Wright, Joseph Levermore, Yukari Ishikawa
Summary: Microplastic pollution is a global concern for the environment and human health. In order to assess the potential hazards associated with high concentrations of microplastics, it is necessary to have a comprehensive understanding of exposure concentrations. Infrared and near-infrared microspectroscopies have been used to analyze microplastics in various matrices, and recent advances in technology have allowed for the use of multivariate and machine learning algorithms. This article provides an up-to-date review of the literature on measuring microplastic exposure using infrared spectroscopy and highlights the recent advancements in this field.
APPLIED SPECTROSCOPY
(2023)
Article
Pharmacology & Pharmacy
Mahdieh Dagina Pedersen, Andrew Megarry, Kaisa Naelapaa, Thomas Rades, Jenni Pessi
Summary: The compression behavior of oral formulations of proteins and peptides can be challenging due to the addition of poorly compactable permeation enhancers. This study demonstrates that tailoring the properties of peptide or protein particles can overcome the poor compression behavior, particularly in high-dose tablet formulations. Small and non-hollow spray-dried insulin particles showed the most significant enhancement in tabletability, especially in poorly tabletable formulations. The particle properties of the active pharmaceutical ingredient (API) play a crucial role in the manufacturability evaluation of poorly tabletable formulations.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Pharmacology & Pharmacy
Jacob Rune Jorgensen, Wolfgang Mohr, Matthias Rischer, Andreas Sauer, Shilpa Mistry, Anette Mullertz, Thomas Rades
Summary: In this study, the stability and intrinsic dissolution of vacuum compression molded (VCM) amorphous solid dispersions (ASDs) of efavirenz (EFV) were investigated. The solubility limits of EFV in seven polymers were determined using the melting point depression (MPD) method. The study found that combining preformulation miscibility determination and dissolution studies is important for rational decision-making regarding the stability and viability of ASD formulations.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Pharmacology & Pharmacy
Yixuan Wang, Thomas Rades, Holger Grohganz
Summary: In this study, the composition evolution of the ternary co-amorphous system CAR-TRP-HPMC was investigated by adding HPMC to previously formed binary systems (CAR - TRP + HPMC, CAR - HPMC + TRP and TRP - HPMC + CAR) prepared by ball milling. The miscibility of CAR with TRP was reduced by the addition of HPMC, as hydrogen bonds formed between CAR and polymer. Phase separation and crystallization of CAR and TRP were observed when their solubility limit in HPMC was exceeded. All ternary co-amorphous systems eventually reached the same composition, but followed different paths depending on the initially used binary system.
Article
Pharmacology & Pharmacy
Xiaoyue Xu, Thomas Rades, Holger Grohganz
Summary: It has been observed that water, as a plasticizer, can increase molecular mobility and decrease the glass transition temperature (Tg) in amorphous systems. However, a recent study found an anti-plasticizing effect of water on prilocaine (PRL), which could be used to moderate the plasticizing effect of water in co-amorphous systems. Nicotinamide (NIC) can form co-amorphous systems with PRL. In this study, the Tgs and molecular mobility of hydrated co-amorphous NIC-PRL systems were compared with those of anhydrous systems to investigate the effect of water.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2023)
Article
Pharmacology & Pharmacy
Katharina Holzapfel, Thomas Rades, Claudia S. Leopold
Summary: The influence of an enantiomeric co-former and the preparation method on the solid-state properties and physical stability of co-amorphous systems was investigated in this study. It was found that the chirality of the co-former and the preparation method had an impact on the solid-state properties and physical stability of the systems.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Editorial Material
Pharmacology & Pharmacy
Shyamal Das, Thomas Rades, Arlene McDowell
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Chemistry, Physical
Anas Aljabbari, Abhijeet Girish Lokras, Jacob Judas Kain Kirkensgaard, Thomas Rades, Henrik Franzyk, Aneesh Thakur, Yibang Zhang, Camilla Foged
Summary: We investigated the structural and material properties of siRNA-loaded LPNs using various analytical techniques. The results revealed the self-assembly of lipidoid into lamellar structures, the lateral organization of siRNA between lipidoid bilayers, and the core-shell structure of siRNA-loaded LPNs. The interactions between lipidoid and siRNA were observed, and the inclusion of siRNA affected the phase behavior of lipidoid. These findings contribute to the understanding of siRNA-loaded LPNs and their applications.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Instruments & Instrumentation
Mette Klitgaard, Maja Norgaard Kristensen, Ramakrishnan Venkatasubramanian, Priscila Guerra, Jette Jacobsen, Ragna Berthelsen, Thomas Rades, Anette Mullertz
Summary: This study aimed to improve the preclinical evaluation of new oral drug formulations by investigating the DSS-induced colitis model. Various parameters were evaluated, and the disease activity index, colon length, and histological evaluation of the colon were identified as effective indicators of colitis in rats. The study also found that the DSS-induced colitis affected luminal pH, lipase activity, and concentrations of bile salts, polar lipids, and neutral lipids.
DRUG DELIVERY AND TRANSLATIONAL RESEARCH
(2023)
Article
Pharmacology & Pharmacy
Afnan Bany Odeh, Boushra El-Sayed, Matthias Manne Knopp, Thomas Rades, Lasse Ingerslev Blaabjerg
Summary: This study investigates the influence of PVP concentration and molecular weight on the precipitation inhibition of poorly soluble drugs, albendazole, ketoconazole, and tadalafil. The results showed that increasing the PVP concentration leads to a higher onset of nucleation and a lower precipitation rate, while the medium viscosity has no significant effect on the nucleation and precipitation rate.
Article
Pharmacology & Pharmacy
Peter I. I. I. J. G. Remoto, Karlis Berzins, Sara J. Fraser-Miller, Timothy M. Korter, Thomas Rades, Jukka Rantanen, Keith C. Gordon
Summary: The solid-state landscape of carbamazepine during dehydration was investigated using both low- (-300 to -15, 15 to 300 cm(-1)) and mid- (300 to 1800 cm(-1)) frequency Raman spectroscopy. Density functional theory with periodic boundary conditions was employed to characterize the carbamazepine dihydrate and different forms, which showed good agreement with experimental Raman spectra. The dehydration process of carbamazepine dihydrate at various temperatures (40, 45, 50, 55, and 60 ?) was explored using principal component analysis and multivariate curve resolution, revealing different transformation pathways of solid-state forms. Low-frequency Raman spectroscopy was found to effectively detect the rapid growth and subsequent decline of carbamazepine form IV, which was not as well observed by mid-frequency Raman spectroscopy. These findings highlight the potential benefits of low-frequency Raman spectroscopy in pharmaceutical process monitoring and control.
Article
Pharmacology & Pharmacy
Jacob Rune Jorgensen, Wolfgang Mohr, Matthias Rischer, Andreas Sauer, Shilpa Mistry, Thomas Rades, Anette Muellertz
Summary: The use of amorphous solid dispersions (ASDs) is a commonly applied formulation strategy to improve the oral bioavailability of poorly water-soluble drugs. However, establishing a predictive model for the in vitro-in vivo relationship (IVIVR) has been challenging. This study suggests that drug absorption may be overestimated in in vitro dissolution-permeation (D/P) setups, and proposes a modified D/P setup to improve predictability by avoiding direct dissolution of drug particles in the permeation barrier.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2023)
Article
Pharmacology & Pharmacy
Mengwei Wang, Junbo Gong, Thomas Rades, Ines C. B. Martins
Summary: Ball milling can reduce the particle size of pharmaceutical powders and induce changes in their physical properties. In this study, we prepared three crystal forms of furosemide and used X-ray diffraction and modulated differential scanning calorimetry to characterize the samples. We found that forms I and III directly converted into an amorphous phase, while form II first underwent a polymorphic transition to form I and then gradually lost its crystallinity. The structural relaxation time of the amorphous fraction was longer for forms I and II, while it was shorter for form III, indicating an amorphous-to-amorphous transformation phenomenon.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Medicine, Research & Experimental
Anas Aljabbari, Shinji Kihara, Thomas Rades, Ben J. Boyd, Karlis Berzins
Summary: The adsorption of gut relevant biomolecules onto particles after oral administration of solid oral dosage forms is expected to form a gastrointestinal corona, which could influence solution-mediated solid-state transformations. This study used low-frequency Raman spectroscopy to investigate the in situ solid-state phase transformations under biorelevant conditions and the presence of biomolecules. The results showed a change in the solid-state transformation pathway from amorphous to crystalline drug and the role of biomolecules in influencing these transformations.
MOLECULAR PHARMACEUTICS
(2023)
Review
Pharmacology & Pharmacy
Yuehua Deng, Shiyuan Liu, Yanbin Jiang, Ines C. B. Martins, Thomas Rades
Summary: Multicomponent solid forms can enhance the properties of low molecular weight drugs, but predicting their formation in the early stages of formulation development is challenging. Empirical and computational methods have been developed, with artificial intelligence being the latest research focus.
Article
Chemistry, Multidisciplinary
Ines C. B. Martins, Anders S. Larsen, Anders O. Madsen, Olivia Aalling Frederiksen, Alexandra Correia, Kirsten M. O. Jensen, Henrik S. Jeppesen, Thomas Rades
Summary: Polyamorphism is a controversial solid-state phenomenon that is still not fully understood. In this study, three distinct polyamorphic forms of hydrochlorothiazide were discovered and their interconversions were investigated. Molecular dynamics simulations revealed differences in dihedral angle distributions between two of the polyamorphs, which may explain their different physicochemical properties.