Publications by Pinelopi Moutzouri

Three-Dimensional Atomic-Level Structure of an Amorphous Glucagon-Like Peptide-1 Receptor Agonist

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri, Daria Torodii

Amorphous formulations are increasingly used in the pharmaceutical industry due to their increased solubility, but their structural characterization at atomic-level resolution remains extremely challenging. Here, we characterize the complete atomic-level s ...

American Chemical Society (ACS)2025

Crystal structure validation of verinurad via proton-detected ultra-fast MAS NMR and machine learning

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri, Daria Torodii

The recent development of ultra-fast magic-angle spinning (MAS) (>100 kHz) provides new opportunities for structural characterization in solids. Here, we use NMR crystallography to validate the structure of verinurad, a microcrystalline active pharmaceutic ...

2024

Barriers to resolution in 1H NMR of rotating solids

David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

The role of 1H solid-state NMR in structure elucidation of solids is becoming more preponderant, particularly as faster magic-angle spinning rates (MAS) become available which improve 1H detected assignment strategies. However, current 1H spectral resoluti ...

Academic Press Inc - Elsevier Science2023

Atomic-level structure determination of amorphous molecular solids by NMR

Manuel Cordova, Arthur César Pinon, David Lyndon Emsley, Pinelopi Moutzouri

Structure determination of amorphous materials remains challenging, owing to the disorder inherent to these materials. Nuclear magnetic resonance (NMR) powder crystallography is a powerful method to determine the structure of molecular solids, but disorder ...

Nature Portfolio2023

A General Method for The Structure Determination of Amorphous Drugs By NMR

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri

Int Union Crystallography2023

Two-dimensional Pure Isotropic Proton Solid State NMR

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

One key bottleneck of solid-state NMR spectroscopy is that H-1 NMR spectra of organic solids are often very broad due to the presence of a strong network of dipolar couplings. We have recently suggested a new approach to tackle this problem. More specifica ...

Wiley-VCH Verlag GmbH2023

Pure Isotropic Proton NMR Spectra in Solids using Deep Learning

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

The resolution of proton solid-state NMR spectra is usually limited by broadening arising from dipolar interactions between spins. Magic-angle spinning alleviates this broadening by inducing coherent averaging. However, even the highest spinning rates expe ...

Wiley-VCH Verlag GmbH2023

Spatial Distribution of Functional Groups in Cellulose Ethers by DNP-Enhanced Solid-State NMR Spectroscopy

David Lyndon Emsley, Pierrick Berruyer, Pinelopi Moutzouri

Cellulose ethers are an important class of biosourced polymers. They are typically obtained from by chemical modification of natural cellulosefibers in aheterogeneous process, resulting in heterogeneous distributions of the functional groups in the materia ...

American Chemical Society2022

Atomic-Level Structure of Zinc-Modified Cementitious Calcium Silicate Hydrate

Paul Bowen, Karen Scrivener, Manuel Cordova, David Lyndon Emsley, Anna Morales Melgares, Pinelopi Moutzouri, Ziga Casar, Amrit Venkatesh

It has recently been demonstrated that the addition of zinc can enhance the mechanical strength of tricalcium silicates (C3S) upon hydration, but the structure of the main hydration product of cement, calcium silicate hydrate (C-S-H), in zinc modified form ...

AMER CHEMICAL SOC2022

H-1 Hyperpolarization of Solutions by Overhauser Dynamic Nuclear Polarization with C-13-H-1 Polarization Transfer

David Lyndon Emsley, Yu Rao, Pinelopi Moutzouri, Amrit Venkatesh

Dynamic nuclear polarization (DNP) is a method that can significantly increase the sensitivity of nuclear magnetic resonance. The only effective DNP mechanism for in situ hyperpolarization in solution is Overhauser DNP, which is inefficient for H-1 at high ...

2022

Advanced characterization of regioselectively substituted methylcellulose model compounds by DNP enhanced solid-state NMR spectroscopy

David Lyndon Emsley, Michel Bardet, Pierrick Berruyer, Pinelopi Moutzouri

Dynamic Nuclear Polarization MAS NMR is introduced to characterize model methylcellulose ether compounds at natural isotopic abundance. In particular an approach is provided to determine the position of the methyl ether group within the repeating unit. Spe ...

2021

Pure Isotropic Proton Solid State NMR

David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

Resolution in proton solid state magic angle sample spinning (MAS) NMR is limited by the intrinsically imperfect nature of coherent averaging induced by either MAS or multiple pulse sequence methods. Here, we suggest that instead of optimizing and perfecti ...

2021

The Atomic-Level Structure of Cementitious Calcium Aluminate Silicate Hydrate Determined by NMR

David Lyndon Emsley, Pinelopi Moutzouri

We review our recent paper which resolves the long-standing dilemma of the location and nature of the six-fold coordinated aluminum in calcium aluminate silicate hydrate (C-A-S-H) samples. First principles calculations predict that at high Ca:Si and H2O ra ...

2021

Theory and simulations of homonuclear three-spin systems in rotating solids

David Lyndon Emsley, Gabriele Stevanato, Pinelopi Moutzouri, Bruno Simões de Almeida

The homonuclear dipolar coupling is the internal spin interaction that contributes the most to the line shapes in magic-angle-spinning (MAS) H-1 NMR spectra of solids, and linewidths typically extend over several hundred Hertz, limiting the H-1 resolution. ...

2021

Sensitivity Enhancements in Lithium Titanates by Incipient Wetness Impregnation DNP NMR

David Lyndon Emsley, Snaedis Björgvinsdóttir, Pierrick Berruyer, Pinelopi Moutzouri, Michael Allan Hope

Solid-state NMR spectroscopy is a widely used method for investigating structural and electronic properties of inorganic materials, but its use is often limited by low sensitivity. Here, we show how solvent-generated dynamic nuclear polarization can be use ...

2020

Hyperpolarization transfer pathways in inorganic materials

Nicolas Luc Matthey, David Lyndon Emsley, Brennan James Walder, Snaedis Björgvinsdóttir, Pinelopi Moutzouri

Dynamic nuclear polarization can be used to hyperpolarize the bulk of proton-free inorganic materials in magic angle spinning NMR experiments. The hyperpolarization is generated on the surface of the material with incipient wetness impregnation and from th ...

Academic Press Inc - Elsevier Science2020

The Atomic-Level Structure of Cementitious Calcium Aluminate Silicate Hydrate

Paul Bowen, Karen Scrivener, Aslam Kunhi Mohamed, Jirawan Siramanont, David Lyndon Emsley, Brennan James Walder, Maya Nicole Harris, Pierrick Berruyer, Pinelopi Moutzouri, Mattia Negroni

Despite use of blended cements containing significant amounts of aluminum for over 30 years, the structural nature of aluminum in the main hydration product, calcium aluminate silicate hydrate (C-A-S-H), remains elusive. Using first-principles calculations ...

2020

Fast remote correlation experiments for 1H homonuclear decoupling in solids

David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida

In 1H MAS spectra, the residual homogeneous broadening under MAS is due to a combination of higher-order shifts and splittings. We have recently shown how the two-dimensional anti-z-COSY experiment can be used for the removal of the splittings. However, th ...

Academic Press Inc - Elsevier Science2020

Homonuclear Decoupling in H-1 NMR of Solids by Remote Correlation

David Lyndon Emsley, Federico Maria Paruzzo, Gabriele Stevanato, Pinelopi Moutzouri, Bruno Simões de Almeida

The typical linewidths of H-1 NMR spectra of powdered organic solids at 111 kHz magic-angle spinning (MAS) are of the order of a few hundred Hz. While this is remarkable in comparison to the tens of kHz observed in spectra of static samples, it is still th ...

Wiley-VCH Verlag GmbH2020