Pristine NASICON Electrolyte: A High Ionic Conductivity and Enhanced Dendrite Resistance Through Zirconia (ZrO2) Impurity-free Solid-Electrolyte Design.

Sodium batteries are considered a promising candidate for large-scale grid storage at tropical climate zone, and solid-state sodium metal batteries have a strong proposition as high energy density battery. The main challenge is to develop ultra-pure solid-state ceramic electrolyte and compatible metal interface. Here, a scalable and energy-efficient synthesis strategy of sodium (Na) Super Ionic CONductor, Na1+xZr2SixP3-xO12 (x = 2, NZSP) solid electrolyte, has been introduced with the complete removal of unreacted zirconium oxide (ZrO2) impurities. Additionally, the reaction mechanism for the formation of pure phase NZSP is reported for the first time. The NZSP prepared by utilizing the Zr precursor, i.e., tetragonal zirconium oxide (t-ZrO2) derived from the Zr(OH)4 gets quickly and completely consumed in the synthesis process leaving no unreacted monoclinic ZrO2 impurities. The synthesis process only needs a minimum stay of 4 h, which is three times less than the conventional synthesis method. The elimination of ZrO2 impurities results in a 2.5-fold reduction in grain boundary resistivity, showcasing a total ionic conductivity of 1.75 mS cm-1 at room temperature and a relative density of 98%. The prepared electrolyte demonstrates remarkable resistance to dendrite formation, as evidenced by a high critical current density value of 1.4 mA cm-2.

Escaping the cohort of concern: in vitro experimental evidence supports non-mutagenicity of N-nitroso-hydrochlorothiazide.

In recent years, nitrosamine impurities in pharmaceuticals have been subject to intense regulatory scrutiny, with nitrosamine drug substance-related impurities (NDSRIs) treated as cohort of concern impurities, regardless of predicted mutagenic potential. Here, we describe a case study of the NDSRI N-nitroso-hydrochlorothiazide (NO-HCTZ), which was positive in the bacterial reverse mutation (Ames) test but is unstable under the test conditions, generating formaldehyde among other products. The mutagenic profile of NO-HCTZ was inconsistent with that expected of a mutagenic nitrosamine, exhibiting mutagenicity in the absence of metabolic activation, and instead aligned well with that of formaldehyde. To assess further, a modified Ames system including glutathione (3.3 mg/plate) to remove formaldehyde was developed. Strains used were S. typhimurium TA98, TA100, TA1535, and TA1537, and E. coli WP2 uvrA/pKM101. In this system, formaldehyde levels were considerably lower, with a concomitant increase in levels of S-(hydroxymethyl)glutathione (the adduct formed between glutathione and formaldehyde). Upon retesting NO-HCTZ in the modified system (1.6-5000 µg/plate), a clear decrease in the mutagenic response was observed in the strains in which NO-HCTZ was mutagenic in the original system (TA98, TA100, and WP2 uvrA/pKM101), indicating that formaldehyde drives the response, not NO-HCTZ. In strain TA1535, an increase in revertant colonies was observed in the modified system, likely due to a thiatriazine degradation product formed from NO-HCTZ under Ames test conditions. Overall, these data support a non-mutagenic designation for NO-HCTZ and demonstrate the value of further investigation when a positive Ames result does not align with the expected profile.

Regeneration of LiFePO4 from spent materials: control and influence of Al impurity.

Owing to the rapid increase of lithium iron phosphate (LiFePO4) batteries, recycling and regeneration of LiFePO4 enjoys significances for sustainable development and environmental protection. In this study, an effective regeneration method for spent LiFePO4 materials and the influence of Al impurity on the electrochemical performance of regenerated LiFePO4 were studied. Firstly, 99.26% Fe, 99.52% P, 99.58% Li, 59.36% Al and 20.24% Cu in spent LiFePO4 material were leached with 150 g•L-1 H2SO4. Subsequently, Al removal and control were achieved by simply adjusting the pH value, and FePO4•2H2O precursors with different Al contents were prepared. Specially, the LiFePO4 regenerated by FePO4•2H2O precursor containing 0.096% Al exhibits excellent electrochemical performance with discharge capacity of 145 mAh•g-1, 140.5 mAh•g-1 and 130.9 mAh•g-1 at the current density of 1C, 2C and 5C, respectively.

In silico mediated workflow for rapid development of downstream processing: Orthogonal product-related impurity removal for a Fc-containing therapeutic.

Therapeutic formats derived from the monoclonal antibody structure have been gaining significant traction in the biopharmaceutical market. Being structurally similar to mAbs, most Fc-containing therapeutics exhibit product-related impurities in the form of aggregates, charge variants, fragments, and glycoforms, which are inherently challenging to remove. In this work, we developed a workflow that employed rapid resin screening in conjunction with an in silico tool to identify and rank orthogonally selective processes for the removal of product-related impurities from a Fc-containing therapeutic product. Linear salt gradient screens were performed at various pH conditions on a set of ion-exchange, multimodal ion-exchange, and hydrophobic interaction resins. Select fractions from the screening experiments were analyzed by three different analytical techniques to characterize aggregates, charge variants, fragments, and glycoforms. The retention database generated by the resin screens and subsequent impurity characterization were then processed by an in silico tool that generated and ranked all possible two-step resin sequences for the removal of product-related impurities. A highly-ranked process was then evaluated and refined at the bench-scale to develop a completely flowthrough two-step polishing process which resulted in complete removal of the Man5 glycoform and aggregate impurities with a 73% overall yield. The successful implementation of the in silico mediated workflow suggests the possibility of a platformable workflow that could facilitate polishing process development for a wide variety of mAb-based therapeutics.

Economical and rapid enantioselective, diastereoselective and achiral separation of palonosetron hydrochloride and its impurities using supercritical fluid chromatography.

Simultaneous separation of compounds with multiple chiral centers and highly similar structures presents significant challenges. This study developed a novel supercritical fluid chromatography (SFC) method with reduced organic solvent consumption and robust separation capabilities to address these challenges. The method was applied to simultaneously achieve enantioselective, diastereoselective, and achiral separation of palonosetron hydrochloride and its six impurities. The effects of the polysaccharide-based chiral stationary phase (CSP), modifier, additive, and column temperature on retention and separation were comprehensively evaluated. It was found that a combination of a polysaccharide-based CSP and a single modifier or a mixture of protonic modifiers could not achieve complete separation due to high structural similarity. However, an ADH column and a ternary solvent mixture containing acetonitrile (methanol: acetonitrile: diethylamine, 60:40:0.2, v/v/v) provided satisfying separation, particularly for the enantiomer and diastereomers of palonosetron. Using the optimized method, the enantioselective, diastereoselective, and achiral separation of palonosetron hydrochloride and its six impurities can be accomplished in 18 min under gradient elution. Thermodynamic results indicated that the separation process was entropy driven. A molecular docking study revealed that the separation was mainly achieved through the differences in hydrogen bond and π - π interactions between the analytes and CSP. This study lays the foundation for SFC analysis of palonosetron hydrochloride and provides a reference for the simultaneous SFC separation of the enantiomers, diastereoisomers and structurally similar compounds.

A Study on the Motion Behavior of Metallic Contaminant Particles in Transformer Insulation Oil under Multiphysical Fields.

When using transformer insulation oil as a liquid dielectric, the oil is easily polluted by the solid particles generated in the operation of the transformer, and these metallic impurity particles have a significant impact on the insulation performance inside the power transformer. The force of the metal particles suspended in the flow insulation oil is multidimensional, which will lead to a change in the movement characteristics of the metal particles. Based on this, this study explored the motion rules of suspended metallic impurity particles in mobile insulating oil in different electric field environments and the influencing factors. A multiphysical field model of the solid-liquid two-phase flow of single-particle metallic impurity particles in mobile insulating oil was constructed using the dynamic analysis method, and the particles' motion characteristics in the oil in different electric field environments were simulated. The motion characteristics of metallic impurity particles under conditions of different particle sizes, oil flow velocities, and insulation oil qualities and influencing factors were analyzed to provide theoretical support for the detection of impurity particles in transformer insulation oil and enable accurate estimations of the location of equipment faults. Our results show that there are obvious differences in the trajectory of metallic impurity particles under different electric field distributions. The particles will move towards the region of high field intensity under an electric field, and the metallic impurity particles will not collide with the electrode under an AC field. When the electric field intensity and particle size increase, the trajectory of the metallic impurity particles between electrodes becomes denser, and the number of collisions between particles and electrodes and the motion speed both increase. Under the condition of a higher oil flow velocity, the number of collisions between metal particles and electrodes is reduced, which reduces the possibility of particle agglomeration. When the temperature of the insulation oil changes and the quality deteriorates, its dynamic viscosity changes. With a decrease in the dynamic viscosity of the insulation oil, the movement of the metallic impurity particles between the electrodes becomes denser, the collision times between the particles and electrodes increase, and the maximum motion speed of the particles increases.

Dominant Scattering Mechanisms in Limiting the Electron Mobility of Scandium Nitride.

Electron mobility in nitride semiconductors is limited by electron-phonon, defect, grain-boundary, and dislocation scatterings. Scandium nitride (ScN), an emerging rocksalt indirect bandgap semiconductor, exhibits varying electron mobilities depending on growth conditions. Since achieving high mobility is crucial for ScN's device applications, a microscopic understanding of different scattering mechanisms is extremely important. Utilizing the ab initio Boltzmann transport formalism and experimental measurements, here we show the hierarchy of various scattering processes in restricting the electron mobility of ScN. Calculations unveil that though Fröhlich interactions set an intrinsic upper bound for ScN's electron mobility of ∼524 cm2/V·s at room temperature, ionized-impurity and grain-boundary scatterings significantly reduce mobility. The experimental temperature dependence of mobilities is captured well considering both nitrogen-vacancy and oxygen-substitutional impurities with appropriate ratios, and room-temperature doping dependency agrees well with the empirical Caughey-Thomas model. Furthermore, we suggest modulation doping and polar-discontinuity doping to reduce ionized-impurity scattering in achieving a high-mobility ScN for device applications.

Surface enhanced transmission Raman spectroscopy: Quantitative performances for impurity analysis in complex matrices.

A transmission detection mode was investigated with SERS analyses (SETRS). A comparison between backscattering and transmission detection modes was conducted to demonstrate the feasibility of performing SETRS analyses. The impact of various parameters on the SERS signal intensity such as sample volume, lens collection optic, laser beam size and laser power were then examined. The analytical performances of SETRS were further evaluated through the quantification of an impurity (4-aminophenol) ranging from 3 to 20 µg/mL in a commercial pharmaceutical product using a total error risk-based approach. To account for expected variability of routine analysis, 9 batches of silver nanoparticles suspensions were used and experiments were performed over 5 different days and by 2 operators. Univariate spectral analysis based on a quadratic regression was compared to a multivariate approach using a partial least square regression. The presented results demonstrated that SETRS can be used to determine an impurity in a complex matrix opening new perspectives for quantitative applications.

Exploring the versatility of mass spectrometry: Applications across diverse scientific disciplines.

Mass spectrometry (MS) has become a pivotal analytical tool across various scientific disciplines due to its ability to provide detailed molecular information with high sensitivity and specificity. MS plays a crucial role in various fields, including drug discovery and development, proteomics, metabolomics, environmental analysis, and clinical diagnostics and Forensic science. In this article we are discussing the application of MS across the diverse scientific disciplines by focusing on some classical examples from each field of application. As the technology continues to evolve, it promises to unlock new possibilities in scientific research and practical applications, cementing its position as an essential tool in modern analytical science.

Pure Hexagonal Diamond with Symmetry-Doping Properties.

The difficulties in asymmetrical doping of wide band gap materials, especially for the n-type diamond challenge, hamper their application in electronic devices. Here, we propose doping diamond polytypes with reasonable band structures to solve this problem. Various elements are doped into six diamond polytypes, and their doping behaviors are investigated. The results show that pure hexagonal (2H) diamond has the band gap with a value of 4.42 eV and the smallest carrier effective masses among six calculated diamond polytypes, exhibiting high electron mobility and hole mobility up to 4250 and 5840 cm2·V-1·s-1, respectively. Compared to cubic (3C) diamond, the impurity formation energy in 2H-diamond is reduced, which is attributed to its C3v symmetry. More importantly, 2H-diamond exhibits favorable doping symmetry with a donor level of 0.14 eV for phosphorus and an acceptor level of 0.19 eV for boron, respectively, which originate from smaller effective masses and stronger delocalization at the band edge in 2H-diamond. These ionization energies are smaller than those in 3C-diamond of 0.32 and 0.58 eV, respectively. This reveals that phosphorus and boron in 2H-diamond are more easily excited at room temperature, producing good n- and p-type conductivities. All of these make 2H-diamond a potential candidate for the replacement of 3C-diamond as a wide band gap material theoretically. These provide a way to realize high-quality n-type diamond, giving significant insights into the realization of diamond-based electronic devices. This also supplies a solution for the difficulties in asymmetric doping of other wide band gap materials.

Safety assessment of protein A and derivation of a parenteral health-based exposure limit.

Protein A (PA) is a bacterial cell wall component of Staphylococcus aureus whose function is to bind to Immunoglobulin G (IgG). Given its ability to bind IgG as well as its stability and resistance to harsh acidic and basic cleaning conditions, it is commonly used in the affinity chromotography purification of biotherapeutics. This use can result in levels of PA being present in a drug product and subsequent patient exposure. Interestingly, PA was previously evaluated in clinical trials as well as supporting nonclinical studies, resulting in a database that enables the derivation of a health-based exposure limit (HBEL). Given the widespread use of PA in the pharmaceutical industry, the IQ DruSafe Impurities Safety Working Group (WG) evaluated the available information with the purpose of establishing a harmonized parenteral HBEL for PA. Based on this thorough, collaborative evaluation of nonclinical and clinical data available for PA, a parenteral HBEL of 1.2 µg/kg/dose (60 µg/dose for a 50 kg individual) is expected to be health protective for patients when it is present as an impurity in a biotherapeutic.

Directly Regenerating of Spent LiCoO2 with Gradient F-doped Subsurface towards Ultra-stable Storage Properties.

As great potential recycling strategy, the direct regeneration of spent LiCoO2 (LCO) is beneficial for lowering environmental pollutions and promoting global sustainability. However, owing to the using of binder and electrolyte, some fluorine impurities would be remained into spent materials. Considering the doping behaviors of F-elements, their suitable content introducing would facilitate the energy-storage abilities of regenerated LCO. Herein, through the tailored introduction of F-elements, spent LCO are successfully regenerated with physical-chemical evolutions. Benefitting from the existed oxygen vacancies, the diffusion energy-barrier of F-elements is reduced from 1.73 eV to 0.61 eV, facilitating the establishment of gradient F-doped subsurface, along with the formation of rigid CoO5F. Meanwhile, excess F-elements (1 wt.%, as a threshold) lead to the formation of LiF passivation layer on the surface. Thus, the as-optimized sample displays a considerable capacity of 154.4 mAh g-1 even at 5.0 C, with retention rate (88.3%) in 3.0~4.5V. Supported by detailed electrochemical and kinetic analysis, the structural advantages are confirmed to boost the improved redox activity of Co-ions and the alleviating of irreversible oxygen-release. Give this, the work is anticipated to reveal the evolutions of regenerated LCO with the introduced F-elements, whilst providing the practical regeneration strategies toward excellent high-voltage properties.

Minimizing Survey Questions for PTSD Prediction Following Acute Trauma.

Traumatic experiences have the potential to give rise to post-traumatic stress disorder (PTSD), a debilitating psychiatric condition associated with impairments in both social and occupational functioning. There has been great interest in utilizing machine learning approaches to predict the development of PTSD in trauma patients from clinician assessment or survey-based psychological assessments. However, these assessments require a large number of questions, which is time consuming and not easy to administer. In this paper, we aim to predict PTSD development of patients 3 months post-trauma from multiple survey-based assessments taken within 2 weeks post-trauma. Our objective is to minimize the number of survey questions that patients need to answer while maintaining the prediction accuracy from the full surveys. We formulate this as a feature selection problem and consider 4 different feature selection approaches. We demonstrate that it is possible to achieve up to 72% accuracy for predicting the 3-month PTSD diagnosis from 10 survey questions using a mean decrease in impurity-based feature selector followed by a gradient boosting classifier.

Poisoning Mechanism Map for Metal Hydride Hydrogen Storage Materials.

The effective utilization of hydrogen storage materials (HSMs) is hindered by impurity gas poisoning, posing a significant challenge for large-scale applications. This study elucidates the poisoning mechanisms of various impurities gases (CO, CO2, O2, Ar, He, CH4, N2) on ZrCo, Pd, U and LaNi5. Impurities gases are categorized into active and inactive types based on their effecting behaviors and mechanisms on the hydrogenation of HSMs. During the hydrogenation process, active impurities chemically poison the hydrogenation reaction by limiting hydrogen absorption at interface, while inactive impurities physically hinder hydrogenation reaction by impeding hydrogen diffusion in hydrogen-impurity mixed gas. In situ Scanning Tunneling Microscope clarifies these behaviors, and a novel criterion based on hydrogen spontaneous dissociation energy is introduced to explain and predict impurity-substrate interaction characteristics. The novel findings of this work provide a comprehensive framework for designing long-lived HSMs with poisoning resistance, guiding the development of more resilient hydrogen storage systems.

Optimized analysis for related substances in spiramycin based on high performance liquid chromatography with hybrid particle column and characterization of its impurities by single heartcut two-dimensional liquid chromatography coupled with quadrupole time-of-flight mass spectrometer.

This article described the development and validation of a method for spiramycin related substances based on hybrid particle column. The chromatographic conditions were as follows: water - 0.2 mol/L dipotassium hydrogen phosphate (the pH value adjusted to 9.5 using a 1 mol/L KOH solution) - acetonitrile - methanol (10: 60: 28.5: 1.5, v/v/v/v) as mobile phase A, water - 0.2 mol/L dipotassium hydrogen phosphate (pH 9.5) - acetonitrile - methanol (10: 30: 57: 3, v/v/v/v) as mobile phase B and gradient elution was performed. Compared with previous analytical methods, this method has strong specificity, excellent sensitivity and stability, which could be used for the daily testing of related substances of spiramycin. Furthermore, impurities above 0.1 % were characterized using two-dimensional liquid chromatography coupled with quadrupole time-of-flight mass spectrometer (2D LC-QTOF-MS/MS) and there were 6 impurities reported for the first time.

Transient Phase-Mediated Li+ Transportation in the Lithium Lanthanum Titanate Solid-State Electrolyte.

The lithium lanthanum titanium oxide (LLTO) perovskite is one type of superior lithium (Li)-ion conductor that is of great interest as a solid-state electrolyte for all-solid-state lithium batteries. Structural defects and impurity phases formed during the synthesis of LLTO largely affect its Li-ion conductivity, yet the underlying Li+ diffusion mechanism at the atomic scale is still under scrutiny. Herein, we use aberration-corrected transmission electron microscopy to perform a thorough structural characterization of the LLTO ceramic pellet. We reveal a prevalent transient phase transition of (La, Ti)2O3 existing at the antiphase boundaries between single-crystalline LLTO domains. This transient phase exhibits a specific crystal orientation with the LLTO phase and shows a gradual structural transition to a tetragonal LLTO structure, which enables detailed crystallographic analysis to correlate their formation to the sintering process of LLTO powders into ceramic pellets. We also find that Li diffusion is retarded by this phase and correlated with the excess amount of La, which is corroborated by the theoretical evaluation of the atomistic mechanisms of Li diffusion across this phase.

Global Perspectives on Mycotoxin Reference Materials (Part I): Insights from Multi-Supplier Comparison Study Including Aflatoxin B1, Deoxynivalenol and Zearalenone.

We conducted a comprehensive examination of liquid mycotoxin reference standards. A total of 30 different standards were tested, each containing 10 samples of three distinct substances: Aflatoxin B1, Deoxynivalenol, and Zearalenone. The standards were sourced from 10 different global market leading manufacturers. To facilitate comparison, all the standard sets were adjusted to the same concentration level. The standards were analyzed using the techniques LC-MS/MS, HPLC-DAD, and LC-HRMS to assess their quality attributes. Regarding the validation of the reference values, it was observed that 30% of the suppliers provided reference standards that were either below the lower acceptance limit or above the higher acceptance limit, confirmed by both the LC-MS/MS and HPLC-DAD methods. Furthermore, a total of 12 impurities were found in the DON standards, 10 in the AFB1 standards, and 8 in the ZON standards, distributed across all the suppliers. Therefore, this study suggests relevant adjustments to the ISO 17034 standard, proposing that the purity of a raw material should be uniformly based on q-NMR analysis, as most manufacturers state the purity of their certificates is determined using HPLC-UV or LC-MS/MS. Liquid standards with a shelf life of ≤1 year should not exceed an uncertainty of 3%. Standards that have a longer shelf life should not have more than 5% uncertainty. This study also emphasizes the importance of stability. The standards should undergo continuous long-term monitoring; otherwise, products may exhibit a target value of only 80%, as seen in one instance. It is also recommended to include proof of HPLC and LC-MS/MS analyses on the certificate of each released batch of a final product.

Nonlinear models based on leaf architecture traits explain the variability of mesophyll conductance across plant species.

Mesophyll conductance ( g m ${g}_{{\rm{m}}}$ ) describes the efficiency with which CO 2 ${\mathrm{CO}}_{2}$ moves from substomatal cavities to chloroplasts. Despite the stipulated importance of leaf architecture in affecting g m ${g}_{{\rm{m}}}$ , there remains a considerable ambiguity about how and whether leaf anatomy influences g m ${g}_{{\rm{m}}}$ . Here, we employed nonlinear machine-learning models to assess the relationship between 10 leaf architecture traits and g m ${g}_{{\rm{m}}}$ . These models used leaf architecture traits as predictors and achieved excellent predictability of g m ${g}_{{\rm{m}}}$ . Dissection of the importance of leaf architecture traits in the models indicated that cell wall thickness and chloroplast area exposed to internal airspace have a large impact on interspecific variation in g m ${g}_{{\rm{m}}}$ . Additionally, other leaf architecture traits, such as leaf thickness, leaf density and chloroplast thickness, emerged as important predictors of g m ${g}_{{\rm{m}}}$ . We also found significant differences in the predictability between models trained on different plant functional types. Therefore, by moving beyond simple linear and exponential models, our analyses demonstrated that a larger suite of leaf architecture traits drive differences in g m ${g}_{{\rm{m}}}$ than has been previously acknowledged. These findings pave the way for modulating g m ${g}_{{\rm{m}}}$ by strategies that modify its leaf architecture determinants.

Analytical Procedure Development and Proposed Established Conditions: A Case Study of a Mass Spectrometry Based NDSRI Analytical Procedure.

With the finalization of the ICH Q14 Analytical Procedure Development guideline, how to apply enhanced approaches (such as analytical quality by design (AQbD)) to develop an analytical procedure, and to propose Established Conditions (ECs) and corresponding reporting categories, is increasingly being discussed. To gain practical experience in applying an enhanced approach for method development and identifying ECs, we developed, validated, and implemented an analytical procedure for a nitrosamine drug substance-related impurity (NDSRI). Here, as an example of the application of Q12 Lifecycle Management guideline principles in regards to analytical procedures, we briefly elaborate how: 1) the principles documented in the ICH Q14 guideline for analytical procedure development were applied, with the focus on identifying an Analytical Target Profile (ATP), knowledge management and risk assessment; 2) analytical procedure robustness according to the recommendations in ICH Q2(R2) Validation of Analytical Procedure guideline and Q14, were evaluated; and 3) mass spectrometry ECs and associated proposed reporting categories were proposed.

Rapid identification of antibody impurities in size-based electrophoresis via CZE-MS generated spectral library.

Methods for the reliable and effective detection and identification of impurities are crucial to ensure the quality and safety of biopharmaceutical products. Technical limitations constrain the accurate identification of individual impurity peaks by size-based electrophoresis separations followed by mass spectrometry. This study presents a size-based electrophoretic method for detecting and identifying impurity peaks in antibody production. A hydrogen sulfide-accelerated degradation method was employed to generate known degradation products observed in bioreactors that forms the basis for size calibration. LabChip GXII channel electrophoresis enabled the rapid (< 1 min) detection of impurity peaks based on size, while capillary zone electrophoresis-mass spectrometry (CZE-MS) facilitated their accurate identification. We combine these techniques to examine impurities resulting from cell culture harvest conditions and forced degradation to assess antibody stability. To mimic cell culture harvest conditions and the impact of forced degradation, we subjected samples to cathepsin at different pH buffers or exposed them to high pH and temperature. Our method demonstrated the feasibility and broad applicability of using a CZE-MS generated spectral library to unambiguously assign peaks in high throughput size-based electrophoresis (i.e., LabChip GXII) with identifications or likely mass of the antibody impurity. Overall, this strategy combines the utility of CZE-MS as a high-resolution separation and detection method for impurities with size-based electrophoresis methods that are typically used to detect (not identify) impurities during the discovery and development of antibody therapeutics.