Sofia Garakyaraghi

@sgarakyaraghi.bsky.social

Associate Publisher ACS Central Science #OpenAccess ACS Publications. @JAgFoodChem @JACS_Au @ChemMater @ACSMatLett 👩🏻‍🔬PhD chemist. Opinions my own

Cool work by Cassandra Callmann & team in ACS Cent Sci reporting a sugar-like polymer that removes heavy metals from water by forming a recyclable precipitate. As proof-of-concept, the polymer removed Cd & Pb from river water spiked with these persistent contaminants pubs.acs.org/doi/10.1021/...

Bioinspired, Carbohydrate-Containing Polymers Efficiently and Reversibly Sequester Heavy Metals

Water scarcity and heavy metal pollution are significant challenges in today’s industrialized world. Conventional heavy metal remediation methods are often inefficient and energy-intensive, and produc...

pubs.acs.org

During my time at Pfizer I solved crystal structures for our COVID-19 antiviral, nirmatrelvir. This compound has two remarkably similar anhydrous polymorphs, which presented significant challenges to getting this drug on the market in a short time. A major team effort: pubs.acs.org/doi/abs/10.1...

Tale of Two Polymorphs: Investigating the Structural Differences and Dynamic Relationship between Nirmatrelvir Solid Forms (Paxlovid)

Two anhydrous polymorphs of the novel antiviral medicine nirmatrelvir were discovered during the development of Paxlovid, Pfizer’s oral Covid-19 treatment. A comprehensive experimental and computational approach was necessary to distinguish the two closely related polymorphs, herein identified as Forms 1 and 4. This approach paired experimental methods, including powder X-ray diffraction and single-crystal X-ray diffraction, solid-state experimental methods, thermal analysis, solid-state nuclear magnetic resonance and Raman spectroscopy with computational investigations comprising crystal structure prediction, Gibbs free energy calculations, and molecular dynamics simulations of the polymorphic transition. Forms 1 and 4 were ultimately determined to be enantiotropically related polymorphs with Form 1 being the stable form above the transition temperature of ∼17 °C and designated as the nominated form for drug development. The work described in this paper shows the importance of using highly specialized orthogonal approaches to elucidate the subtle differences in structure and properties of similar solid-state forms. This synergistic approach allowed for unprecedented speed in bringing Paxlovid to patients in record time amidst the pandemic.

pubs.acs.org

The first FDA-approved drug for frostbite can save limbs from amputation, and researchers are working on “coldscreen” preventatives. Check out "The Fight Against Frostbite Progresses" latest from @cenmag.bsky.social special for ACS Central Science. ❄️ pubs.acs.org/doi/10.1021/... #ChemSky

The Fight Against Frostbite Progresses

The first FDA-approved drug for frostbite can save limbs from amputation, and researchers are working on “coldscreen” preventatives.

pubs.acs.org

Light-triggered structural gating for directional electron transfer. ⚡ Work by Jerry Meyer, Elena Galoppini, @fncastellano.bsky.social and co-workers. "Structural Gating Enhances Long-Distance Light-Driven Interfacial Electron Transfer" Read it here: pubs.acs.org/doi/10.1021/... #ChemSky

Structural Gating Enhances Long-Distance Light-Driven Interfacial Electron Transfer

Structural gating provides a molecular means to transfer electrons preferentially in one desired vectorial direction, a behavior needed for applications in artificial photosynthesis. At the interfaces utilized herein, visible-light absorption by a transition metal complex opens a “structural gate” by planarization of otherwise rotating phenyl rings in p-phenylene ethynylene (PE) bridge units. Planarization provides a conjugated pathway for electron flow toward a conductive oxide surface. Interfacial electron transfer to the oxide restores rotation and closes the gate to the unwanted recombination reaction. This structural gating results in nearly quantitative long-distance (>20 Å) interfacial electron transfer that occurs ∼1000 times faster than transfer in the opposite direction. A comparative kinetic study of these complexes with those that contain ionic bridge units, without gating function, as a function of the applied potential and hence −ΔG° provided a physical basis for the structural gating. A small distance-dependent reorganization energy with weak electronic coupling underlies the success of this gate that enables efficient long-distance electron transfer and slow recombination.

pubs.acs.org