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Elucidating details of biology's selective uptake and trafficking of rare earth elements, particularly the lanthanides, has the potential to inspire sustainable biomolecular separations of these essential metals for myriad modern technologies. Here, we biochemically and structurally characterize Methylobacterium (Methylorubrum) extorquens LanD, a periplasmic protein from a bacterial gene cluster for lanthanide uptake. This protein provides only four ligands at its surface-exposed lanthanide-binding site, allowing for metal-centered protein dimerization that favors the largest lanthanide, LaIII. However, the monomer prefers NdIII and SmIII, which are disfavored lanthanides for cellular utilization. Structure-guided mutagenesis of a metal-ligand and an outer-sphere residue weakens metal binding to the LanD monomer and enhances dimerization for PrIII and NdIII by 100-fold. Selective dimerization enriches high-value PrIII and NdIII relative to low-value LaIII and CeIII in an all-aqueous process, achieving higher separation factors than lanmodulins and comparable or better separation factors than common industrial extractants. Finally, we show that LanD interacts with lanmodulin (LanM), a previously characterized periplasmic protein that shares LanD's preference for NdIII and SmIII. Our results suggest that LanD's unusual metal-binding site transfers less-desirable lanthanides to LanM to siphon them away from the pathway for cytosolic import. The properties of LanD show how relatively weak chelators can achieve high selectivity, and they form the basis for the design of protein dimers for separation of adjacent lanthanide pairs and other metal ions. [ABSTRACT FROM AUTHOR]

Human milk oligosaccharides (HMOs) are an important class of biomolecules responsible for the healthy development of the brain‐gut axis of infants. Unfortunately, their accurate characterization is largely precluded due to a variety of reasons – there are over 200 possible HMO structures whereas only 10s of these are available as authentic analytical standards. Furthermore, their isomeric heterogeneity stemming from their many possible glycosidic linkage positions and corresponding α/β anomericities further complicates their analyses. While liquid chromatography coupled to tandem mass spectrometry remains the gold standard for HMO analyses, it often times cannot resolve all possible isomeric species and thus warrants the development of other orthogonal approaches. High‐resolution ion mobility spectrometry coupled to mass spectrometry has emerged as a rapid alternative to condensed‐phase separations but largely has remained limited to qualitative information related to the resolution of isomers. In this work, we have assessed the use of permethylation to improve both the resolution and sensitivity of HMO analyses with cyclic ion mobility separations coupled with mass spectrometry. In addition to this, we have developed the first‐ever high‐resolution collision cross‐section database for permethylated HMOs using our previously established calibration protocol. We envision that this internal reference database generated from high‐resolution cyclic ion mobility spectrometry‐mass spectrometry will greatly aid in the accurate characterization of HMOs and provide a valuable, orthogonal, approach to existing liquid chromatography–tandem mass spectrometry‐based methods. [ABSTRACT FROM AUTHOR]

Identification of features with high levels of confidence in liquid chromatography–mass spectrometry (LC–MS) lipidomics research is an essential part of biomarker discovery, but existing software platforms can give inconsistent results, even from identical spectral data. This poses a clear challenge for reproducibility in biomarker identification. In this work, we illustrate the reproducibility gap for two open-access lipidomics platforms, MS DIAL and Lipostar, finding just 14.0% identification agreement when analyzing identical LC–MS spectra using default settings. Whilst the software platforms performed more consistently using fragmentation data, agreement was still only 36.1% for MS2 spectra. This highlights the critical importance of validation across positive and negative LC–MS modes, as well as the manual curation of spectra and lipidomics software outputs, in order to reduce identification errors caused by closely related lipids and co-elution issues. This curation process can be supplemented by data-driven outlier detection in assessing spectral outputs, which is demonstrated here using a novel machine learning approach based on support vector machine regression combined with leave-one-out cross-validation. These steps are essential to reduce the frequency of false positive identifications and close the reproducibility gap, including between software platforms, which, for downstream users such as bioinformaticians and clinicians, can be an underappreciated source of biomarker identification errors. [ABSTRACT FROM AUTHOR]

In view of the mounting requirements for courses in nuclear chemistry and radiochemistry, hands-on experience in the separations of radioisotopes is imperative. Three separation techniques commonly used were introduced, coprecipitation, liquid-liquid extraction, and ion-exchange chromatography. Their principles and the associated fundamental thermodynamic concepts are detailed. Their respective experimental applications to the separations of radioisotopes of one rare earth element (europium) and two transition metals (cobalt and nickel) are discussed. In-classroom experimental settings are proposed, and experiment outcomes are presented, which can be beneficial for future implementation within nuclear chemistry and radiochemistry programs in higher education.

Herein, I provide a personal perspective on high‐resolution multipass ion mobility spectrometry‐mass spectrometry (IMS‐MS), with a specific emphasis on cyclic (cIMS) and structures for lossless ion manipulations (SLIM IMS)‐based separations. My overarching goal for this perspective was to detail what I believe will be the key important areas in which IMS‐MS will help shape the bioanalytical community and especially omics‐based research. [ABSTRACT FROM AUTHOR]

Paclitaxel is one of the most important chemotherapy agents and it has shown activity against a variety of human cancers. In the past years several derivatives and formulations have been developed to improve its activity and reduce its toxicity. Recently, 1,18‐Octadecanedioic acid‐Paclitaxel (ODDA‐PTX), obtained by conjugation of paclitaxel with a long‐chain diacid, has emerged as a promising paclitaxel prodrug, with high efficacy and low toxicity. A novel strategy for its synthesis has been developed and is herein described. The approach is based on the mono‐allyl protection of octadecanedioic acid (ODDA) and on the Pd‐catalyzed removal of the allyl ester after coupling with paclitaxel. This strategy is superior to previously reported procedures in that it affords the ODDA‐PTX product with much higher purity, avoids chromatographic purifications and can be practically scaled‐up for the industrial production of ODDA‐PTX. [ABSTRACT FROM AUTHOR]

This paper focuses on 3D printing using digital light processing (DLP) to create microchannel devices with inner diameters of 100, 200, and 500 µm and cater flow-through applications within the realm of analytical chemistry, in particular high-pressure liquid chromatographic separations. Effects of layer thickness and exposure time on channel dimensions and surface roughness were systematically investigated. Utilizing a commercially accessible 3D printer and acrylate resin formulation, we fabricated 100–500 µm i.d. squared and circular channel designs minimizing average surface roughness (< 20%) by applying a 20-µm layer thickness and exposure times ranging from 1.1 to 0.7 s. Pressure resistance was measured by encasing microdevices in an aluminum chip holder that integrated flat-bottom polyetheretherketon (PEEK) nanoports allowing to establish the micro-to-macro interface to the HPLC instrument. After thermal post-curing and finetuning the clamping force of the chip holder, a maximum pressure resistance of 650 bar (1.5% RSD) was reached (n = 3). A polymer monolithic support structure was successfully synthesized in situ with the confines of a 500 µm i.d. 3D printed microchannel. A proof-of-concept of a reversed-phase chromatographic gradient separation of intact proteins is demonstrated using an aqueous-organic mobile-phase with isopropanol as organic modifier. [ABSTRACT FROM AUTHOR]

Identification of features with high levels of confidence in liquid chromatography–mass spectrometry (LC–MS) lipidomics research is an essential part of biomarker discovery, but existing software platforms can give inconsistent results, even from identical spectral data. This poses a clear challenge for reproducibility in biomarker identification. In this work, we illustrate the reproducibility gap for two open-access lipidomics platforms, MS DIAL and Lipostar, finding just 14.0% identification agreement when analyzing identical LC–MS spectra using default settings. Whilst the software platforms performed more consistently using fragmentation data, agreement was still only 36.1% for MS2 spectra. This highlights the critical importance of validation across positive and negative LC–MS modes, as well as the manual curation of spectra and lipidomics software outputs, in order to reduce identification errors caused by closely related lipids and co-elution issues. This curation process can be supplemented by data-driven outlier detection in assessing spectral outputs, which is demonstrated here using a novel machine learning approach based on support vector machine regression combined with leave-one-out cross-validation. These steps are essential to reduce the frequency of false positive identifications and close the reproducibility gap, including between software platforms, which, for downstream users such as bioinformaticians and clinicians, can be an underappreciated source of biomarker identification errors.

Summary: In response to escalating environmental concerns surrounding antibiotic pollution, the utilization of calcium-montmorillonite minerals for tetracycline wastewater treatment is gaining prominence. This study systematically analyzed the physicochemical properties of calcium-montmorillonite through scanning electron microscope, contact angle analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. It explored the adsorption efficacy and mechanisms for tetracycline removal, considering factors like initial pH, adsorption duration, concentration, and co-cations (Na+ and Ca2+). Under optimized conditions, achieving over 90% tetracycline removal with a maximum adsorption capacity of 526 mg/g, the study revealed competitive adsorption sites for coexisting cations. The Langmuir model best described the monolayer adsorption process, while kinetic studies favored the pseudo-first-order model. This research offers comprehensive insights into tetracycline adsorption on calcium-montmorillonite, emphasizing its potential as an efficient, cost-effective adsorbent for pharmaceutical wastewater treatment.

Field-flow fractionation (FFF) is a family of single-phase separative techniques exploited to gently separate and characterize nano- and microsystems in suspension. These techniques cover an extremely wide dynamic range and are able to separate analytes in an interval between a few nm to 100 µm size-wise (over 15 orders of magnitude mass-wise). They are flexible in terms of mobile phase and can separate the analytes in native conditions, preserving their original structures/properties as much as possible. Molecular biology is the branch of biology that studies the molecular basis of biological activity, while biotechnology deals with the technological applications of biology. The areas where biotechnologies are required include industrial, agri-food, environmental, and pharmaceutical. Many species of biological interest belong to the operational range of FFF techniques, and their application to the analysis of such samples has steadily grown in the last 30 years. This work aims to summarize the main features, milestones, and results provided by the application of FFF in the field of molecular biology and biotechnology, with a focus on the years from 2000 to 2022. After a theoretical background overview of FFF and its methodologies, the results are reported based on the nature of the samples analyzed. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) ranks as the third most frequently diagnosed cancer and the second leading cause of cancer-related deaths. The current endoscopic-based or stool-based diagnostic techniques are either highly invasive or lack sufficient sensitivity. Thus, there is a need for less invasive and more sensitive screening approaches. We, therefore, conducted a study on 64 human serum samples representing three different groups (adenocarcinoma, adenoma, and control) using cutting-edge GC×GC–LR/HR-TOFMS (comprehensive two-dimensional gas chromatography coupled with low/high-resolution time-of-flight mass spectrometry). We analyzed samples with two different specifically tailored sample preparation approaches for lipidomics (fatty acids) (25 μL serum) and metabolomics (50 μL serum). In-depth chemometric screening with supervised and unsupervised approaches and metabolic pathway analysis were applied to both datasets. A lipidomics study revealed that specific PUFA (ω-3) molecules are inversely associated with increased odds of CRC, while some PUFA (ω-6) analytes show a positive correlation. The metabolomics approach revealed downregulation of amino acids (alanine, glutamate, methionine, threonine, tyrosine, and valine) and myo-inositol in CRC, while 3-hydroxybutyrate levels were increased. This unique study provides comprehensive insight into molecular-level changes associated with CRC and allows for a comparison of the efficiency of two different analytical approaches for CRC screening using same serum samples and single instrumentation. [ABSTRACT FROM AUTHOR]

Ensuring continuous and sustainable lithium supply requires the development of highly efficient separation processes such as LLE (liquid‐liquid extraction) for both primary sources and certain waste streams. In this work, 4‐phosphoryl pyrazolones are used in an efficient pH‐controlled stepwise separation of Li+ from Ca2+, Mg2+, Na+ and K+. The factors affecting LLE process, such as the substitution pattern of the extractant, diluent/water distribution, co‐ligand, pH, and speciation of the metal complexes involved, were systematically investigated. The maximum extraction efficiency of Li+ at pH 6.0 was 94 % when Mg2+ and Ca2+ were previously separated at pH<5.0, proving that the separation of these ions is possible by simply modulating the pH of the aqueous phase. Our study points a way to separation of lithium from acid brine or from spent lithium ion battery leaching solutions, which supports the future supply of lithium in a more environmentally friendly and sustainable manner. [ABSTRACT FROM AUTHOR]

Electrochemical upcycling of nitrate into ammonia at ambient conditions offers a sustainable synthesis pathway that can complement the current industrial NH3 production from the Haber–Bosch process. One of the key rate‐limiting steps is the effective desorption of gaseous or interfacial bubble products, mainly NH3 with some minor side products of nitrogen and hydrogen, from the electrode surfaces to sustain available sites for the NO3− reduction reaction. To facilitate the gaseous product desorption from the catalytic sites, hydrophobic polytetrafluoroethylene (PTFE) nanoparticles are blended within a CuO catalyst layer, which is shown to eliminate the undesirable accumulation and blockage of electrode surfaces and largely decouples the electron‐ and phase‐transfer processes. The NH3 partial current density normalized by the electrochemically active surface area (ECSA) increases by nearly a factor of 17.8 from 11.4 ± 0.1 to 203.3 ± 1.8 mA cm−2ECSA. The DFT and ab‐initio molecular dynamics simulations suggest that the hydrophobic PTFE nanoparticles may serve as segregated islands to enhance the spillover and transport the gaseous products from electrocatalysts to the PTFE. Thus, a higher ammonia transfer is achieved for the mixed PTFE/CuO electrocatalyst. This new and simple strategy is expected to act as inspiration for future electrochemical gas‐evolving electrode design. [ABSTRACT FROM AUTHOR]

Instrument automation, technological advancements and improved computational power made separation science an extremely data-rich approach, requiring the use of statistical and data analysis tools that are able to optimize processes and combine multiple outputs. The use of chemometrics is growing, greatly improving the ability to extract meaningful information. Separation–multidetection generates multidimensional data, whose elaboration should not be left to the discretion of the operator. However, some applications or techniques still suffer from the lack of method optimization through DoE and downstream multivariate analysis, limiting their potential. This review aims at summarizing how chemometrics can assist analytical chemists in terms of data elaboration and method design, focusing on what can be achieved by applying chemometric approaches to separation science. Recent applications of chemometrics in separation analyses, in particular in gas, liquid and size-exclusion chromatography, together with field flow fractionation, will be detailed to visualize the state of the art of separation chemometrics, encompassing volatile, soluble and solid (colloidal) analytes. The samples considered will range from food chemistry and environmental chemistry to bio/pharmaceutical science. [ABSTRACT FROM AUTHOR]

Scheme 1. Schematic illustration of COFs in analytical applications. [Display omitted] • Key aspects of COFs design and common synthetic methods were briefly summarized. • The applications of COFs for sample pretreatment are summarized in depth, including sample extraction and enrichment, enzymes immobilization. • Recent advances in COFs for separation, chemical sensing, and nanozyme sensing are summarized and evaluated in detail. • The challenges in separation mechanism, relationship of structure and performance, and current issues in accurate detection are discussed. Covalent organic frameworks (COFs) have emerged as a new kind of crystalline porous material constructed from organic building blocks through dynamic covalent bonds. The desired COFs can be synthesized through the condensation of pre-designed building blocks. With multitudinously unique characteristics, such as tunable aperture, high specific surface area, excellent stability, enzyme-like activities, and fluorescent properties, COFs have found widespread applications in the field of analytical chemistry. This review introduces the structure and properties of COFs to illustrate how they can be purposefully constructed according to specific application requirements. Subsequently, we detail the analytical applications and advancements of COFs in sample pretreatment, separation science, and chemical sensing. The enzyme-like activities of COFs and the sensing strategies of COFs-based nanozymes are also summarized. Furthermore, potential challenges and further development prospects are also discussed for the further advancement of COFs in analytical applications. [ABSTRACT FROM AUTHOR]

The presence of monoclonal antibody (mAb) fragments in pharmaceutical mAb products is a critical quality attribute and should be controlled for safety. Several mAb fragments derived from clip formation in the complementarity determining regions (CDRs), as well as from cleavage in the hinge region, have been reported. However, the properties of CDR-clipped variants are not fully understood because of difficulties in separating them from intact mAbs under non-denaturing conditions due to similarities in size. We have established a method for separating CDR-clipped variants under non-denaturing conditions using an appropriate size exclusion chromatography column. 1 In this report, we provide a comprehensive characterization of a CDR-clipped variant from bevacizumab. The variant exhibited a lower pI, a higher tendency to form dimers, and a lower affinity for both neonatal Fc receptor (FcRn) and Fcγ receptor (FcγR). The effects of clip formation in CDR H3 on the higher order structure were analyzed by hydrogen/deuterium exchange mass spectrometry, and the observed changes in the structures of the VH, CH2, and VL domains were in agreement with the lowered affinity for antigen, FcRn, and FcγR. These findings suggest that clip formation in the CDR may affect the efficacy, safety, and pharmacokinetics of pharmaceutical mAbs. [ABSTRACT FROM AUTHOR]

A number of recommendations on how to improve the education and training of separation scientists were recently made by the National Academies of Sciences, Engineering, and Mathematics in their report, A Research Agenda for Transforming Separation Science. This perspective outlines how some of these recommendations may be fulfilled by examining trends in potential curriculum topics related to the field and new technological platforms for interactive content delivery. Identifying and adopting the best practices within these emerging educational directions will ensure the future success of the field. [ABSTRACT FROM AUTHOR]

Nanoplastic pollution is increasing worldwide and poses a threat to humans, animals, and ecological systems. High-throughput, reliable methods for the isolation and separation of NMPs from drinking water, wastewater, or environmental bodies of water are of interest. We investigated iron oxide nanoparticles (IONPs) with hydrophobic coatings to magnetize plastic particulate waste for removal. We produced and tested IONPs synthesized using air-free conditions and in atmospheric air, coated with several polydimethylsiloxane (PDMS)-based hydrophobic coatings. Particles were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), superconducting quantum interference device (SQUID) magnetometry, dynamic light scattering (DLS), X-ray diffraction (XRD) and zeta potential. The IONPs synthesized in air contained a higher percentage of the magnetic spinel phase and stronger magnetization. Binding and recovery of NMPs from both salt and freshwater samples was demonstrated. Specifically, we were able to remove 100% of particles in a range of sizes, from 2–5 mm, and nearly 90% of nanoplastic particles with a size range from 100 nm to 1000 nm using a simple 2-inch permanent NdFeB magnet. Magnetization of NMPs using IONPs is a viable method for separation from water samples for quantification, characterization, and purification and remediation of water. [ABSTRACT FROM AUTHOR]

Currently, chemists seem more fascinated with exploiting less hazardous green solvent ionic liquids for countering the detrimental consequence of organic solvents on the environment. Ordinarily, ionic liquids having salt-like structures comprise cations and anions. Ionic liquids alleviate various enzyme-catalyzed reactions having excellent yields, increasing capacities and functions, enhancing recyclability, increasing stability, recovery, and cost-effectiveness, and these are cardinal elements for applications in industry. Furthermore, growing nanotechnology, polymer, electrochemistry, environmental chemistry, pharmaceutical medicinal chemistry or pharmaceutical chemistry, and biochemistry in the area of ionic liquids have been flourished among investigators. Ionic liquids-supported materials and techniques are excellent for efficient and sustainable procedures. Because of their assignment as designer solvents, through which the physiochemical dimensions of an Ionic liquid can be adjusted for better functioning for peculiar applications. The review delivers the gradual improvement, growth or development, or progress and prospects of ionic liquids and their physicochemical properties as well as examples of applications in a unified fashion. [ABSTRACT FROM AUTHOR]

• Sole-monomer sulfobetaine derivative functionalized zwitterionic hydrophilic materials is fabricated within only 1 h. • High column efficiency and superhydrophilicity are achieved on the monolith. • It exhibits excellent enrichment performances for glycopeptides and good separation ability for small bioactive molecules. • It showed high selectivity and sensitivity for the detection of plasma Aβ42/40 or steroid hormones. Analysis of bioactive polar molecules is crucial for different fields, including biology, clinic medicine, and separation science. However, the design of the separation materials remains a huge challenge due to their tedious preparation process and limited chromatographic performances of traditional hydrophilic materials. New-generation hydrophilic polymer materials prepared via a sole-monomer system exhibit excellent reproducibility and chromatographic efficiency; however, such polymers reported to date have a high swelling propensity and risk of low surface exposure of functional groups, which limit their application as separation materials. In this study, N , N -bis(methacryloxyethyl)- N -methyl- N -(3-sulfopropyl)ammonium betaines (BMMSB), a zwitterionic sulfobetaine, was used to rapidly fabricate the zwitterionic hypercrosslinked hydrophilic polymer materials via the sole-monomer system. The novel hypercrosslinked hydrophilic materials exhibited high porosity and permeability, superhydrophilicity, low protein adsorption, and excellent capillary column efficiency (up to 134,950 plates/m for thiourea). It was able to enrich 28 N -glycopeptides from hIgG tryptic digests with a higher efficiency than that of traditional poly(SPE- co -EDMA) monolith and commercial ZIC-HILIC materials. Additionally, the polyBMMSB hydrophilic materials demonstrated superior selectivity and column efficiency to the poly(SPE- co -EDMA) monolith for the separation of various small bioactive molecules, including nucleobases and nucleosides, phenol derivatives, benzoic acid derivatives, urea and allantoin. Especially, high performance bioanalysis of Alzheimer's disease biomarkers plasma Aβ42 and Aβ40, or some steroid hormones in human plasma were also achieved by the polyBMMSB monolith combined with nano liquid chromatography-mass spectrometry. As such, these sulfobetaine-based zwitterionic polymers may serve as a prototypical next-generation zwitterionic hydrophilic materials for rapid and efficient bioanalysis. [ABSTRACT FROM AUTHOR]

Preparative thin-layer chromatography (prepTLC) is a commonly used method of purification suitable for small-scale reactions. However, descriptions of the preferred methodology to load, run, and recover samples from prepTLC are non-standard and varied, making it part of the 'hidden curriculum' of laboratory techniques. In this article we report on the simple, cost-effective methods we use to load and collect samples from a plate, which enhance the convenience, speed, and precision of this technique. [ABSTRACT FROM AUTHOR]

Summary: Polymeric membranes with high permeance and selectivity performances are anticipated approach for water treatment. Separation membranes with moderate molecular weight cut-offs (MW in between 400 and 700 g mol−1) are desirable to separate multivalent ions and small molecules from a water stream. This requires polymeric membranes with controlled pore, pore size distribution, surface charge, and thin active layer to maximize membrane performance. Here, a fabrication of the polyaryl nanofilm with thickness down to ∼15 nm synthesized using interfacial polymerization onto ultrafiltration supports is described. Electron microscopy analysis reveals the presence of crumpled surface morphology in polyaryl nanofilm. Polyaryl nanofilm shows high water permeance of ∼110 Lm−2h−1 bar−1. Polyaryl nanofilm presents molecular weight cut-off greater than ∼450 gmol−1 (molecular marker) with water permeance of ∼84 Lm−2h−1 bar−1. Multivalent salt (K3[Fe(CN)6]) has higher rejection (>95%) as compared to the monovalent (∼5%) and divalent salt (∼28%) with the water permeance of ∼81 Lm−2h−1 bar−1.

Summary: Controlling the ion transport through graphene oxide (GO) membrane is challenging, particularly in the aqueous environment due to its strong swelling tendency. Fine-tuning the interlayer spacing and chemistry is critical to create highly selective membranes. We investigate the effect of single-site divalent cations in tuning GO membrane properties. Competitive ionic permeation test indicates that Cu2+ cations dominate the transport through the 2D channels of GO membrane over other cations (Mg2+/Ca2+/Co2+). Without/With the single-site M2+ modifications, pristine GO, Mg-GO, Ca-GO, and Cu-GO membranes show interlayer spacings of ∼13.6, 15.6, 14.5, and 12.3 Å in wet state, respectively. The Cu-GO membrane shows a two-fold decrease of NaCl (1 M) permeation rate comparing to pristine GO, Mg-GO, and Ca-GO membranes. In reverse osmosis tests using 1000 ppm NaCl and Na2SO4 as feeds, Cu-GO membrane shows rejection of ∼78% and ∼94%, respectively, which are 5%–10% higher than its counterpart membranes.

Recently, ion mobility spectrometry-mass spectrometry (IMS-MS) has become more readily incorporated into various omics-based workflows. These growing applications are due to developments in instrumentation within the last decade that have enabled higher-resolution ion mobility separations. Two such platforms are the cyclic (cIMS) and structures for lossless ion manipulations (SLIM), both of which use traveling wave ion mobility spectrometry (TWIMS). High-resolution separations achieved with these techniques stem from the drastically increased pathlengths, on the order of 10 s of meters to >1 km, in both cIMS-MS and SLIM IMS-MS, respectively. Herein, we highlight recent developments and advances, for the period 2019-2023, in high-resolution traveling wave-based IMS-MS through instrumentation, calibration strategies, hyphenated techniques, and applications. Specifically, we will discuss applications including CCS calculations in multipass IMS-MS separations, coupling of IMS-MS with chromatography, imaging, and cryogenic infrared spectroscopy, and isomeric separations of glycans, lipids, and other small metabolites., (© 2024 The Author(s). Mass Spectrometry Reviews published by Wiley Periodicals LLC.)

The content of monoclonal antibody (mAb) fragments in pharmaceutical mAb products is a critical quality attribute and should be controlled for safety. Peptide bonds in the hinge region of mAbs are susceptible to hydrolysis, generating Fc-Fab fragments, which are associated with lower efficacy than the intact antibody. Fc-Fab fragments can be separated from intact antibody molecules under native conditions by size exclusion chromatography (SEC). Although several fragments generated by a clip in the complementarity determining region (CDR) have been reported, their efficacies have not been analyzed. This is because these fragments could not be separated from intact antibodies under native conditions owing to their similar molecular sizes. Here, we report that bevacizumab variant with clipping in the CDR, with the resulting fragments remaining intact in the variant, can be isolated under native conditions by selecting an adequate SEC column. [ABSTRACT FROM AUTHOR]

Summary: Light olefins are the precursors of all modern-day plastics. Olefin is always mixed with paraffins in the time of production, and therefore it needs to be separated from paraffins to produce polymer-grade olefin. The state-of-the-art separation technique, cryogenic distillation, is highly expensive and hazardous. Adsorption could be a novel, sustainable, and inexpensive separation strategy, provided a suitable adsorbent can be designed. There are different types of mechanisms that were harnessed for the separation of olefins by adsorption, and in this review, we have focused our discussion on those mechanisms. These mechanisms include, (a) Affinity-based separation, like pi complexation and hydrogen bonding, (b) Separation based on pore size and shape, like size-exclusion and gate-opening effect, and (c) Non-equilibrium separation, like kinetic separation. In this review, we have elaborated each of the separation strategies from the fundamental level and explained their roles in the separation processes of different types of paraffins and olefins.

[Display omitted] • A Novel PG-MCDI system for efficient NH 4 + recovery. • ORR was designed to keep high interfacial pH in EDL, sustaining NH 3 conversion. • Ti 3 C 2 Tx -based materials enhance EDL capacitance and ORR performance. • Achieved 278 mg N /g removal capacity and 0.73 kWh/kg N energy consumption at 1.5 V. This study addresses the challenge of efficient ammonium recovery from wastewater, a key issue in global nitrogen cycle management. A novel capacitive deionization (CDI) system, which innovatively integrated a gas diffusion membrane and a proton exchange membrane, called PG-MCDI, was firstly reported to realize NH 4 + recovery from wastewater. This system was specifically designed to regulate the cathode side reaction, particularly oxygen reduction reaction (ORR), to control the local pH near cathode surface to maintain 8 ∼ 10. The pH change can affect the NH 4 +/NH 3 equilibrium, resulted in a speciation change from NH 4 + to NH 3 ·NH 3 will thus be extracted from the feed solution through gas diffusion membrane. Further, Ti 3 C 2 T x -based particles were developed with enhanced NH 4 + adsorption capacity through graphite C doping and a macroporous structure, alongside proper ORR performance reinforced by redox couple TiX+/Ti4+ to keep high interfacial pH. This dual-functional approach significantly improved the NH 4 + removal capacity. The integrated PG-MCDI exhibited excellent NH 4 + removal capacity of 278 mg N g−1 and energy consumption of 0.73 kWh kg−1N at 1.5 V, which are superior to other electrochemical systems. The PG-MCDI system assembled with Ti 3 C 2 T x -based cathode can be routinely employed as an effective strategy to address the energy and environmental issues of recovering NH 4 + from wastewater. [ABSTRACT FROM AUTHOR]

Separation of glow stick dyes adhered to a cotton swab using liquid CO2 provides an engaging demonstration of several chemical concepts including polarity, kinetics, chemiluminescence, and the importance of CO2 a green solvent. The simple protocol allows access to a broad range of students. Differential polarities of the glow stick dyes allow certain dyes to be preferentially dissolved in liquid CO2, leaving other dyes adhered onto cotton. Both TCPO (bis(2,4,6-trichlorophenyl)oxalate) and H2O2, which together provide the necessary reaction for chemiluminescence, are present in both the extracted liquid and cotton upon dissipation of CO2. Thus, it is possible to compare the emission spectrum of the extracted fluid to that of the original glow stick and the residue left on the cotton swab. Emission peaks resulting from the presence of polar dyes in the original glow stick and on the cotton are routinely observed to be missing in the extracts.

Nanoplastic pollution is increasing worldwide and poses a threat to humans, animals, and ecological systems. High-throughput, reliable methods for the isolation and separation of NMPs from drinking water, wastewater, or environmental bodies of water are of interest. We investigated iron oxide nanoparticles (IONPs) with hydrophobic coatings to magnetize plastic particulate waste for removal. We produced and tested IONPs synthesized using air-free conditions and in atmospheric air, coated with several polydimethylsiloxane (PDMS)-based hydrophobic coatings. Particles were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), superconducting quantum interference device (SQUID) magnetometry, dynamic light scattering (DLS), X-ray diffraction (XRD) and zeta potential. The IONPs synthesized in air contained a higher percentage of the magnetic spinel phase and stronger magnetization. Binding and recovery of NMPs from both salt and freshwater samples was demonstrated. Specifically, we were able to remove 100% of particles in a range of sizes, from 2–5 mm, and nearly 90% of nanoplastic particles with a size range from 100 nm to 1000 nm using a simple 2-inch permanent NdFeB magnet. Magnetization of NMPs using IONPs is a viable method for separation from water samples for quantification, characterization, and purification and remediation of water.

Summary: Rare earth separation is still a major challenge in membrane science. Nitrogen-doped nanoporous graphene (NDNG) is a promising material for membrane separation, but it has not yet been tested for rare earth separation, and it is limited by multi-complex synthesis. Herein, we developed a one-step, facile, and scalable approach to synthesize NDNG with tunable pore size and controlled nitrogen content using confinement combustion. Nanoporous hydrotalcite from Zn(NO3)2 is formed between layers of graphene oxide (GO) absorbed with phenylalanine via confinement growth, thus preparing the sandwich hydrotalcite/phenylalanine/GO composites. Subsequently, area-confinement combustion of hydrotalcite nanopores is used to etch graphene nanopores, and the hydrotalcite interlayer as a closed flat nanoreactor induces two-dimensional space confinement doping of planar nitrogen into graphene. The membrane prepared by NDNG achieves separation of Sc3+ from the other rare earth ions with excellent selectivity (∼3.7) through selective electrostatic interactions of pyrrolic-N, and separation selectivity of ∼1.7 for Tm3+/Sm3+.

A fresh look back at the chemistry of Bi3+ spanning solid state structural studies, aqueous biphasic separations, and a chromatographic purification of 213 Bi in support of its clinical use in targeted radiotherapy reveals the foundational importance of coordination chemistry and understanding the preferences exhibited by both the metal center and the ligand(s). Select structural studies of the nitrate and halide salts of Bi3+ complexes with the cyclic crown ethers and acyclic polyethylene glycols (PEGs) are reviewed, and the structure of [BiCl3(cis-anti-cis-dicyclohexano-18-crown-6)] is reported and compared to related structures. Liquid/liquid distribution studies emphasizing Bi3+ partitioning in PEG-based aqueous biphasic systems are presented and show that the distribution ratios using halide anions as extractants increase in the expected order: F- < Cl- < Br- < I-. Building on an understanding of the Bi-directed coordination chemistry in halide containing systems, the rationale for a chromatographic purification of 213 Bi is discussed, as are the performance data showing a 96% recovery of chemically and radionuclidically pure 213 Bi in just 0.25 mL of a strip solution that is directly compatible with binding to carboxylate-based biolocalization agents. The importance of coordination chemistry and an interdisciplinary scientific approach are highlighted, as are select future opportunities in targeted radiotherapy. [ABSTRACT FROM AUTHOR]

Dye removal from industrial waste water has become an important issue. The highvisibility, undesirability and recalcitrance are the significant environmental problemfor the dyes. In the present work,β‐cyclodextrin functionalized KCC‐1 (KCC‐1‐NH‐β‐CD)was synthesized and utilized to the removal of hazardous malachite green. In order to study the morphology of the synthesized nano adsorbent, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were obtained from the surface of the sample. Additionally, the functionalization of KCC‐1 with β‐cyclodextrin was confirmed with Furrier Transform Infrared spectroscopy (FTIR). The textural property of KCC‐1 was verified using nitrogen adsorption/ desorption analysis (BET equation). UV‐Vis spectroscopy utilized for the investigation of malachite green by KCC‐1‐NH‐β‐CD. Specific surface area of the adsorbent was calculated to be 140 m2/g and it can be stated that the synthesized nano adsorbent has high removal efficiency. It should be noted that the adsorption capacity of the employed nano adsorbent was more than 95%, which could be attributed to high porosity of β‐cyclodextrin functionalized KCC‐1. [ABSTRACT FROM AUTHOR]

Methods that determine the relative purity of biopharmaceuticals represent the most widely used form of analysis for the pharmaceutical industry. The ability to rapidly assess method capability or the uncertainty of measurements under actual use conditions continues to present significant challenges. We have refined and applied the model of Uncertainty Based on Current Information to predict the precision of the purity measurements and compared the predicted precision to the measured variability for several different types of purity methods. The measured method variability was derived from the analysis of data sets ranging from hundreds to thousands of measurements for each different method type. The predicted precision was found to be in excellent agreement with the statistically obtained values with R2 = 0.94. This demonstration of concurrence between the predicted and actual precision provides an opportunity for streamlining laborious conventional (statically derived) assessment of method precision and leveraging the Uncertainty Based on Current Information model utilizing much smaller data sets or even a single experiment. [ABSTRACT FROM AUTHOR]

Separation, analysis and recycling technologies are of high interest for our modern societies, where colloidal iron and aluminium (hydr)oxides have important applications. However, there are significant gaps in the fundamental understanding of how these phases form in real systems. Classical nucleation theory cannot account for many experimental observations, and there is a dichotomy between the chemistry of hydrolysing/condensating systems and the physical notion of supersaturation. Reviewing parts of the established and recent literature, we demonstrate that concepts of nonclassical nucleation pathways can overcome these issues. This broader, chemistry-based conceptual framework has a high potential for advancing current applications, and developing new strategies towards separation, analysis and recycling applications, which seem to be urgently required for the future. [ABSTRACT FROM AUTHOR]

In this study, a series of zwitterionic phosphorylcholine functionalized monolithic columns were fabricated via the thermally initiated co-polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and different hydrophilic crosslinkers, including 1,4-bis(acryloyl)piperazine (PDA), N,N′-methylenebisacrylamide (MBA) and 2-(methacryloyloxy)ethyl-[N-(2-methacryloyloxy)ethyl]phosphorylcholine (MMPC). The physicochemical and chromatographic properties of these MPC functionalized monoliths, including column morphology, pore size distribution, permeability, column efficiency, retention mechanism and ζ-potential analysis, were systematically compared. Furthermore, the influence of the crosslinker on the chromatographic performance of these MPC functionalized monoliths was evaluated. The chromatographic results indicate that the polarity of MPC functionalized monoliths may be related to the polarity of the crosslinker, which further affects the column selectivity and efficiency. A particularly high column efficiency (88,000 plates/m) was obtained on the novel poly(MPC- co -MMPC) monolith at optimum linear velocity using thiourea as test analyte. Compared to the poly(MPC- co -MBA) and poly(MPC- co -PDA) monoliths, the poly(MPC- co -MMPC) monolith exhibited higher separation selectivity for polar analytes, including nucleobases, nucleosides and benzoic acid derivatives. Moreover, 24 N -glycopeptides could be detected after enrichment with the poly(MPC- co -MMPC) versus 19 and 10 N -glycopeptides with the poly(MPC- co -MBA) and poly(MPC- co -PDA) monoliths, and no N -glycopeptide without enrichment. Therefore, MMPC has a great potential as a new and alternative hydrophilic crosslinker for the development of zwitterionic polymeric monoliths. Image 1 • The polarity of zwitterionic monolithic materials is related to the polarity of the crosslinker, which further affects column selectivity and efficiency. • The novel poly(MPC- co -MMPC) monolith exhibited high column efficiency, selectivity for polar analytes as well as good enrichment potential for N -glycopeptides. • MMPC has a great potential as a new and alternative hydrophilic crosslinker for the development of zwitterionic monolithic materials. [ABSTRACT FROM AUTHOR]

In response to escalating environmental concerns surrounding antibiotic pollution, the utilization of calcium-montmorillonite minerals for tetracycline wastewater treatment is gaining prominence. This study systematically analyzed the physicochemical properties of calcium-montmorillonite through scanning electron microscope, contact angle analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. It explored the adsorption efficacy and mechanisms for tetracycline removal, considering factors like initial pH, adsorption duration, concentration, and co-cations (Na + and Ca 2+ ). Under optimized conditions, achieving over 90% tetracycline removal with a maximum adsorption capacity of 526 mg/g, the study revealed competitive adsorption sites for coexisting cations. The Langmuir model best described the monolayer adsorption process, while kinetic studies favored the pseudo-first-order model. This research offers comprehensive insights into tetracycline adsorption on calcium-montmorillonite, emphasizing its potential as an efficient, cost-effective adsorbent for pharmaceutical wastewater treatment., Competing Interests: The authors declare no competing interests., (© 2024.)

Separation of glow stick dyes adhered to a cotton swab using liquid CO2 provides an engaging demonstration of several chemical concepts including polarity, kinetics, chemiluminescence, and the importance of CO2 a green solvent. The simple protocol allows access to a broad range of students. Differential polarities of the glow stick dyes allow certain dyes to be preferentially dissolved in liquid CO2, leaving other dyes adhered onto cotton. Both TCPO (bis(2,4,6-trichlorophenyl)oxalate) and H2O2, which together provide the necessary reaction for chemiluminescence, are present in both the extracted liquid and cotton upon dissipation of CO2. Thus, it is possible to compare the emission spectrum of the extracted fluid to that of the original glow stick and the residue left on the cotton swab. Emission peaks resulting from the presence of polar dyes in the original glow stick and on the cotton are routinely observed to be missing in the extracts. [ABSTRACT FROM AUTHOR]