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ACS Omega Jun 2024An efficient method has been developed for the synthesis of α-deuterated α-amino esters via hydrogen isotope exchange of α-amino esters in DO with...
An efficient method has been developed for the synthesis of α-deuterated α-amino esters via hydrogen isotope exchange of α-amino esters in DO with 2-hydroxynicotinaldehyde as a catalyst under mild conditions. This methodology exhibits a wide range of substrate scopes, remarkable functional group tolerance, and affording the desired products in good yields with excellent deuterium incorporation. Notably, the ortho-hydroxyl group and the pyridine ring of the catalyst play a crucial role in the catalytic activity, which not only stabilizes the carbon-anion intermediates but also enhances the acidity of the amino esters' α-C-H bond.
PubMed: 38947810
DOI: 10.1021/acsomega.3c09974 -
Cureus May 2024A rare complication, 5-oxoproline-induced high anion gap metabolic acidosis (HAGMA) is associated with chronic acetaminophen use, predominantly reported in outpatient...
A rare complication, 5-oxoproline-induced high anion gap metabolic acidosis (HAGMA) is associated with chronic acetaminophen use, predominantly reported in outpatient settings. However, its occurrence in hospitalized patients, particularly those with end-stage renal disease (ESRD), remains underreported. We present a case of a 74-year-old female with ESRD on hemodialysis who developed HAGMA highly suspicious for 5-oxoproline toxicity from acetaminophen usage following cardiac surgery. Despite a standard analgesic dose, the patient's renal impairment likely predisposed her to 5-oxoproline accumulation, resulting in severe metabolic acidosis. Discontinuation of acetaminophen led to the resolution of HAGMA, highlighting the importance of recognizing this rare but potentially life-threatening complication in the inpatient and critical care setting. This case suggests a potential interaction between acetaminophen metabolism and renal dysfunction in the pathogenesis of 5-oxoproline-induced HAGMA.
PubMed: 38947688
DOI: 10.7759/cureus.61328 -
ACS Central Science Jun 2024Protein-based therapeutics comprise a rapidly growing subset of pharmaceuticals, but enabling their delivery into cells for intracellular applications has been a...
Protein-based therapeutics comprise a rapidly growing subset of pharmaceuticals, but enabling their delivery into cells for intracellular applications has been a longstanding challenge. To overcome the delivery barrier, we explored a reversible, bioconjugation-based approach to modify the surface charge of protein cargos with an anionic "cloak" to facilitate electrostatic complexation and delivery with lipid nanoparticle (LNP) formulations. We demonstrate that the conjugation of lysine-reactive sulfonated compounds can allow for the delivery of various protein cargos using FDA-approved LNP formulations of the ionizable cationic lipid DLin-MC3-DMA (MC3). We apply this strategy to functionally deliver RNase A for cancer cell killing as well as a full-length antibody to inhibit oncogenic β-catenin signaling. Further, we show that LNPs encapsulating cloaked fluorescent proteins distribute to major organs in mice following systemic administration. Overall, our results point toward a generalizable platform that can be employed for intracellular delivery of a wide range of protein cargos.
PubMed: 38947210
DOI: 10.1021/acscentsci.4c00071 -
RSC Advances Jun 2024A new eco-friendly method for creating an optical sensor membrane specifically designed to detect yttrium ions (Y) has been developed. The proposed sensor membrane is...
A new eco-friendly method for creating an optical sensor membrane specifically designed to detect yttrium ions (Y) has been developed. The proposed sensor membrane is fabricated by integrating 4-(2-arsonophenylazo) salicylic acid (APASA), sodium tetraphenylborate (Na-TPB), and tri--octyl phosphine oxide (TOPO) into a plasticized poly(vinyl chloride) matrix with dimethyl sebacate (DMS) as the plasticizer. In this sensor membrane, APASA functions dually as an ionophore and a chromoionophore, while TOPO enhances the complexation of Y ions with APASA. The composition of the sensor membrane has been meticulously optimized to achieve peak performance. The current membrane exhibits a linear dynamic range for Y ions from 8.0 × 10 to 2.3 × 10 M, with detection and quantification limits of 2.3 × 10 and 7.7 × 10 M, respectively. No interference from other potentially interfering cations and anions was observed in the determination of Y. The membrane showed strong stability and a swift response time of about 3.0 minutes, with no signs of APASA leaching. This sensor is highly selective for Y ions and can be renewed by treating it with 0.15 M HNO. It has been effectively applied to measure Y in nickel-based alloys, as well as in biological and environmental samples.
PubMed: 38946767
DOI: 10.1039/d4ra03854a -
Chemical Communications (Cambridge,... Jul 2024I hydrolysis, sluggish iodine redox kinetics and the instability of Zn anodes are the primary challenges for aqueous four-electron zinc-iodine batteries (4eZIBs)....
I hydrolysis, sluggish iodine redox kinetics and the instability of Zn anodes are the primary challenges for aqueous four-electron zinc-iodine batteries (4eZIBs). Herein, the OTf anion chemistry in aqueous electrolyte is essential for developing advanced 4eZIBs. It is elucidated that OTf anions establish weak hydrogen bonds (H bonds) with water to stabilize I species while optimizing a water-lean Zn coordination structure to mitigate Zn dendrites and corrosion. Moreover, the interaction of the OTf anions with the iodine species results in an increased equilibrium average intermolecular bond length of the iodine species, facilitating the 4e redox kinetics of iodine with improved reversibility.
PubMed: 38946686
DOI: 10.1039/d4cc02266a -
Advanced Science (Weinheim,... Jul 2024Amphiphilic block copolymers are promising candidates for the fabrication of ultrafiltration membranes with an isoporous integral asymmetric structure. The membranes are...
Amphiphilic block copolymers are promising candidates for the fabrication of ultrafiltration membranes with an isoporous integral asymmetric structure. The membranes are typically fabricated by the combination of block copolymer self-assembly and the non-solvent-induced phase separation (SNIPS) process resulting in isoporous integral asymmetric membranes. Certainly, all these membranes lack thermal and chemical stability limiting the usage of such materials. Within this study, the fabrication of completely cross-linked isoporous integral asymmetric block copolymer membranes is demonstrated by UV cross-linking resulting in chemical and thermal stable ultrafiltration membranes. The UV cross-linking process of PVBCB-b-P4VP (poly(4-vinylbenzocyclobutene)-b-poly(4vinylpyridine)) block copolymer membranes in dependency of irradiation time, intensity, distance between membrane and UV source and the wavelength is investigated. Furthermore, it is shown that the penetration depths can be increased by soaking the membranes in wave-guiding solutions before UV cross-linking is carried out. Moreover, a completely new and easy cross-linking strategy is developed based on isorefractive solvents resulting in thermal and chemically stable membranes that are cross-linked through the whole membrane thickness. Finally, the new cross-linking strategy in isorefractive solutions is transferred to commercial PVDF and PAN-co-PVC polymer membranes paving the way for more stable and sustainable ultrafiltration membranes.
PubMed: 38946670
DOI: 10.1002/advs.202403288 -
Advanced Science (Weinheim,... Jul 2024Zintl phases typically exhibit low lattice thermal conductivity, which are extensively investigated as promising thermoelectric candidates. While the significance of...
Zintl phases typically exhibit low lattice thermal conductivity, which are extensively investigated as promising thermoelectric candidates. While the significance of Zintl anionic frameworks in electronic transport properties is widely recognized, their roles in thermal transport properties have often been overlooked. This study delves into KCdSb as a representative case, where the [CdSb] tetrahedrons not only impact charge transfer but also phonon transport. The phonon velocity and mean free path, are heavily influenced by the bonding distance and strength of the Zintl anions Cd and Sb, considering the three acoustic branches arising from their vibrations. Furthermore, the weakly bound Zintl cation K exhibits localized vibration behaviors, resulting in strong coupling between the high-lying acoustic branch and the low-lying optical branch, further impeding phonon diffusion. The calculations reveal that grain boundaries also contribute to the low lattice thermal conductivity of KCdSb through medium-frequency phonon scattering. These combined factors create a glass-like thermal transport behavior, which is advantageous for improving the thermoelectric merit of zT. Notably, a maximum zT of 0.6 is achieved for KNaCdSb at 712 K. The study offers both intrinsic and extrinsic strategies for developing high-efficiency thermoelectric Zintl materials with extremely low lattice thermal conductivity.
PubMed: 38946664
DOI: 10.1002/advs.202402209 -
Materials Horizons Jul 2024Birefringent crystals can manipulate the phase and polarization of light, so they are widely used as essential components in various optical devices. Common strategies...
Birefringent crystals can manipulate the phase and polarization of light, so they are widely used as essential components in various optical devices. Common strategies to construct birefringent crystals are introducing metal cations that are either able to realize favorable coordination with functional anionic units or are susceptible to polarizability anisotropy. Herein, we report a metal-free crystal, NH(HCNO)·2HO, synthesized using the facile solution method. In the crystal structure of NH(HCNO)·2HO, (HCNO) functional units are assembled in an optimal manner by cooperative non-covalent interactions, , hydrogen bonding and π-π interactions. As a result, this metal-free crystal possesses exceptional birefringence up to 0.54@550 nm, which is larger than those of most metal-containing birefringent crystals. In addition, the interference color of this crystal does not change obviously from 243 K to 313 K, indicating that the birefringence is robust at different temperatures. This work will inspire useful insights into the role of non-covalent interactions in designing outstanding birefringent crystals for efficient polarized optical devices.
PubMed: 38946550
DOI: 10.1039/d4mh00422a -
Dalton Transactions (Cambridge, England... Jul 2024In this work, PbSbO-type oxides LaMTeO (M = Ga and Mn) were synthesized and structurally characterized by Rietveld refinements against high-resolution X-ray powder...
In this work, PbSbO-type oxides LaMTeO (M = Ga and Mn) were synthesized and structurally characterized by Rietveld refinements against high-resolution X-ray powder diffraction data. The Ga/Te partial ordering within the honeycomb-like two-dimensional [GaTeO] anionic layer leads to the loss of the inversion center between Ga and Te; however the inversion center on the 3̄-roto-inversion axis is preserved, thereby resulting in a 2-fold PbSbO-type superstructure by doubling the -axis associated with a structural symmetry descending from the original 3̄1 to 3̄1 symmetry. In contrast, LaMnTeO (2/) adopts a monoclinically distorted 4-fold superstructure with lattice dimensions of ≈ , ≈ √3, ≈ 2, where and represent the lattice parameters of trigonal PbSbO. The formation of this 2/-superstructure is attributed to the combination of complete Mn/Te ordering and the first-order Jahn-Teller distortion of Mn with the electronic configuration of . Such a monoclinic distortion can effectively lift the Mn spin moments arranged on the triangular sublattice, resulting in a sharp peak for antiferromagnetic transition, which is in stark contrast to subtle magnetic transitions for PbSbO-type tellurates AMn(VI)TeO (A = alkaline earth and Pb) and LnCrTeO (Ln = rare earth) with higher structural symmetry. Our findings highlight that the electronic configuration effects of M-cations play a critical role in controlling the structure symmetry of LaMTeO, providing a strategy to fine-tune the crystal structures and physical properties.
PubMed: 38946522
DOI: 10.1039/d4dt01486c -
Journal of Materials Chemistry. B Jul 2024Topical treatment of vitreoretinal diseases remains a challenge due to slow corneal uptake and systemic clearance. Exosomes are emerging nanocarriers for drug delivery...
Topical treatment of vitreoretinal diseases remains a challenge due to slow corneal uptake and systemic clearance. Exosomes are emerging nanocarriers for drug delivery due to biocompatibility and cellular targeting properties. To apply them for retinal targeting the topical route, exosomes must traverse various ocular barriers including the cornea, lens, vitreous humor (VH), and the retina itself. Here we engineered high-purity milk-derived exosomes by anchoring arginine-rich cationic motifs PEG lipid insertion on their surface. Modification enabled exosomes to use weak-reversible electrostatic interactions with anionic glycosaminoglycan (GAG) and water content of the tissue to enhance their transport rate and retention. Addition of cationic motifs neutralized the anionic surface charge of exosomes (-24 to -2 mV) without impacting size or morphology. Cationic-motif-modified exosomes exhibited two-fold faster steady state diffusivity through bovine corneas compared to unmodified exosomes. Fluorescence recovery after photobleaching confirmed that cationic-motif-modified exosomes can diffuse through VH without steric hindrance. In healthy VH, cationic-motif-modified exosomes demonstrated stronger binding resulting in three-fold lower average diffusivity that enhanced by six-fold in 50% GAG-depleted VH recapitulating advanced liquefaction. Cationic-motif-modified exosomes penetrated through the full-thickness of porcine retinal explants resulting in ten-fold higher uptake in photoreceptors and three-fold greater transfection with encapsulated eGFP mRNA compared to unmodified exosomes. Cationic-motif-modified exosomes are safe to use as they did not adversely affect the mechanical swelling properties of the cornea or lens nor impact retinal cell viability. Cationic-motif-modified exosomes, therefore, offer themselves as a cell-free nanocarrier platform for gene delivery to retinal photoreceptors potentially the topical route.
PubMed: 38946491
DOI: 10.1039/d4tb00849a