Journal of Separation Science

The aim of this work was to develop the HPLC‐MS/MS method for the determination of L‐carnitine and creatine in tears, as these molecules can be used as biomarkers of several diseases and health conditions with neurological manifestation, simultaneously with the determination of creatinine as normalization factor. Tears were collected using a microtube during crying or using Schirmer strip by inserting it under the lower eyelid. Due to the low stability of creatine, only a few hours at room temperature, it is advisable to freeze the samples immediately after collection. Different methanol to water contents in the extraction solution were tested (0%–100%). Extraction recovery from Schirmer strips, matrix effect, and overall process efficiency were evaluated for 0.3 and 1 mL of extraction solution used. Finally, the extraction into 1 mL of 80% methanol containing 0.1% formic acid, and subsequent HPLC‐MS/MS separation at isocratic conditions (methanol:water 5:95% with 0.1% formic acid and flow rate of 0.25 mL/min) using a Synergi 4 μ Polar‐RP column (150 × 2 mm) and detection in the positive ion mode was used. The limits of quantifications for L‐carnitine, creatine, and creatinine in tears were 0.5, 1.0, and 1.0 µmol/L, respectively. Intraday and interday precisions were up to 4.4% and bias did not exceed 12% for all analytes. Linearity was tested and approved in the range of 0.23–30 µmol/L for L‐carnitine and 0.78–100 µmol/L for creatine and creatinine. Measured values of L‐carnitine, creatine, and creatinine in real tear samples of healthy individuals (n = 7) were within the range of 1.1–8.2, 4.8–46.3, and 8–44.7 µmol/L, respectively. Obtained results were compared with published results in tears if available (L‐carnitine and creatinine) or with other biological matrices. As our knowledge, this publication is the first that reports the content of creatine in tears.

Glycosylation, a common post‐translational modification, is crucial in various biological processes and diseases. While N‐linked glycans have been widely studied, O‐linked glycans and other small glycan structures, such as glycosphingolipid (GSL) glycans and free oligosaccharides, have been less explored due to their structural complexity and low abundance. To address the challenge of isomeric separation for these small glycans, we employed a mesoporous graphitized carbon (MGC) column, which offers an effective alternative to the nano‐porous graphitized carbon (PGC) column. Previously, the MGC column demonstrated efficient isomeric separation of N‐glycans and glycopeptides. In this study, we optimized chromatographic conditions using standard samples to extend the application of the MGC column to O‐glycans, free oligosaccharides, and GSL glycans. These optimizations resulted in improved retention and isomeric separation. The method was validated through successful isomeric separation of O‐glycans, free oligosaccharides, and GSL glycans derived from human milk, showcasing the MGC column's potential for comprehensive glycomics analysis of biological samples. This study underscores the robustness and reproducibility of the MGC column, highlighting its suitability for advanced glycomics, particularly in biological samples where O‐glycans, GSL glycans, or free oligosaccharides play significant roles in disease progression.

The olive oil industry is currently experiencing a period of significant growth, largely as a result of the high value placed on olive oil as a high‐nutritional food product on a global scale. Industrial olive oil production generates significant quantities of solid waste and dark liquid effluents, involving olive leaves (OLs), olive pomace (OP), and olive mill wastewaters (OMWWs). Particular attention was given to the recycling and valorization of by‐products and biomass from the olive oil industry due to their richness in bioactive compounds, including phenolic compounds with antioxidant properties. The aim of this study was the sustainable recovery and characterization of valuable biocompounds, notably phenols, with particular emphasis on lipophenols, from different matrices (OMWWs, OP, and OLs) of three different Olea europaea cultivars using LC coupled with photodiode array (PDA) and MS detection. Method validation demonstrated satisfactory linearity (R² > 0.9806), repeatability (lower than 9.82%) and recovery (over 79.07%) for all samples investigated. Before quantification, the matrix effect was also evaluated with values ranging from 71.99% to 139.70%.The results highlight that OLs, OP, and OMWWs might be employed for several applications, including nutraceuticals, cosmeceuticals, food, and animal feed.

Alachlor, acetochlor, and metolachlor are organochlorine herbicides extensively used for weed control in agricultural practices, yet their use is prohibited within the European Union due to environmental and health concerns. These compounds and their degradation products exhibit high environmental persistence, necessitating reliable and rapid analytical methods for monitoring. Conventional reversed‐phase liquid chromatography employing C18 columns is commonly utilized for their analysis. However, alkyl silica columns, and especially C18 columns, are not suitable for the effective separation of isomers, necessitating the integration of tandem mass spectrometry for enhanced analytical accuracy. This study explores the application of a porous graphitic carbon‐based column to overcome these limitations. High‐temperature chromatography enabled improved efficiency and selectivity in separating the target compounds. The influence of temperature, flow rate, pH, and mobile phase composition on the retention of alachlor, acetochlor, metolachlor, and their degradation products was systematically evaluated. A method suitable for separation and quantification of the herbicides was developed, highlighting the potential of porous graphitic carbon columns for robust and precise analysis in complex environmental matrices.

New chiral isocratic HPLC conditions were proposed for investigation of moxifloxacin hydrochloride and its potential isomeric impurity (R,R)‐isomer (impurity G) using the chiral additive copper (II)‐sulfate and isoleucine in the mobile phase using an achiral C18 chromatographic column, 150 × 4.6 mm; 3 µm, as a significant improvement of the official European Pharmacopeia method concerning economy and baseline resolution. The mechanism of separation of enantiomers of moxifloxacin using the chiral additive copper (II)‐sulfate is also elucidated. In the optimization of the experimental conditions of the chiral HPLC method, the central composite design was used, and for multiobjective optimization the desirability function with its desired value 1.00 was used. After optimization and method validation the best conditions concerning the concentration of chiral agents (0.01 M), organic solvent content in the mobile phase (30%, v/v methanol), pH value of mobile phase (3.5), and column temperature (23°C) with 10 µL injection volume, were defined. Compared to the pharmacopeial HPLC method, the analysis time was shorter and significantly lower amount of chiral agents in mobile phase was required. The optimized method was validated with respect to linearity, accuracy, precision, and robustness. The linearity of the method has been demonstrated in the range of 0.30–2.50 µg/mL (R² > 0.998). Limit of detection and limit of quantification for moxifloxacin chiral impurity G determination were 0.098 and 0.298 µg/mL, respectively. The method was found to be suitable for quantification of moxifloxacin chiral impurity G in moxifloxacin drug substance.

Epinephrine and norepinephrine are widely used to treat cardiovascular collapse during resuscitation with lipid emulsions in the treatment of drug toxicity including local or non‐local anesthetics. The effect of the lipid emulsion Intralipid on the vasoconstriction induced by epinephrine or norepinephrine is, however, still unknown. In this study, the interaction of epinephrine and norepinephrine with the intravenous Intralipid emulsion was investigated by capillary electromigration techniques. Capillary electrokinetic chromatography was performed to determine the distribution coefficients by running the analytes under different experimental conditions (temperature, ionic strength, and pH) through a capillary filled with the background electrolyte containing Intralipid emulsion. In addition, the binding constants of the epinephrine and norepinephrine complexes with Intralipid emulsion were determined based on the effective electrophoretic mobility data obtained by electrokinetic chromatography at a wide concentration range of Intralipid emulsion. The obtained binding constants, as well as the distribution coefficients determined by electrokinetic chromatography, confirm that epinephrine and norepinephrine are hydrophilic compounds and that they are minimally distributed into the Intralipid emulsion. Therefore, their application as drugs for vasoconstriction upon Intralipid emulsion treatment is well motivated.

In this study, an innovative, rapid, and automated method for quantifying six Gelsemium elegans alkaloids in biological samples using magnetic dispersive solid‐phase extraction (MDSPE) and liquid chromatography tandem mass spectrometry (LC‐MS/MS). Magnetic HLB extractant, NaH2PO4/Na2HPO4 buffer (0.2 M, pH 7) and acetonitrile were used in automatic MDSPE. The average pretreatment time was less than 2 min per sample. Atropine‐d3 was employed as the internal standard (IS). The six alkaloids demonstrated a linear response (R² > 0.997) in the concentration range of 1∼100 ng/mL and 2∼200 ng/g. Precision and accuracy were within ± 15%, and the extraction recovery rates for each alkaloid ranged from 60.32% to 105.32%. The samples were found to be stable under various conditions. In summary, we present the first automated MDSPE‐LC‐MS/MS method for simultaneous quantification of six Gelsemium elegans alkaloids (gelsemine, koumine, humantenmine, humantenine, humantenidine, and humantenirine) in multiple biological matrices (whole blood, urine, liver). Unlike prior studies focused on one to two analytes or single matrices, this method achieves unparalleled specificity for six alkaloids with detection limits up to 0.01 ng/mL (0.02 ng/g), addressing critical gaps in forensic toxicology for complex poisoning cases.

This study developed an efficient separation strategy combining high‐speed countercurrent chromatography and semi‐preparative HPLC for the isolation of sesquiterpenoids from the volatile oil of Dalbergia odorifera, thereby improving the quality control of Xiangdan injection. Initially, the enriched volatile oil was processed using high‐speed countercurrent chromatography with a solvent system of n‐hexane/ethyl acetate/acetonitrile/water (6:1:6:2, v/v/v/v). Within 350 min, four nerolidol oxides were successfully separated, and a sesquiterpenoid compound was markedly enriched. Then, the enriched compound was further purified using semi‐preparative HPLC. HPLC analysis indicated that the strategy successfully separated five sesquiterpenoid compounds from D. odorifera with purities exceeding 91%. Electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy were employed to confirm the structures of five isolated compounds. The five isolated compounds were identified as dalberpene (Compound I), nerolidol oxide I (Compound II), nerolidol oxide II (Compound III), nerolidol oxide III (Compound IV), and nerolidol oxide IV (Compound V). Subsequently, based on the HPLC characteristic chromatogram, the isolated compounds, including dalberpene, nerolidol oxide I, nerolidol oxide II, nerolidol oxide IV, and commercially purchased elemicin, were selected as five target analytes for the quality control of D. odorifera components in Xiangdan injection. The previously developed dispersive liquid–liquid microextraction‐back extraction method was further optimized and rigorously validated. The results indicated that the average concentrations of five target analytes in Xiangdan injection samples ranged from 0.105 to 4.990 µg/mL. Compared with previous studies, this study significantly improved the specificity and accuracy of quality control for D. odorifera components in Xiangdan injection.

In this study, novel covalent/metal–organic skeleton composites (TpBD@MIL‐68; 2,4,6‐triformylphloroglucinol (Tp) and benzidine (BD)) were combined with high‐performance liquid chromatography (HPLC) and used to develop a method for detecting ultraviolet absorbers, including 4‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)benzene‐1,3‐diol (Appolo‐116), 3‐benzenediol, 4‐[4,6‐bis(2,4‐dimethylphenyl)‐1,3,5‐triazin‐2‐yl]‐1 (DBDT), 2,4,6‐triphenyl‐s‐triazine (TPTZ), 2,4,6‐trip‐tolyl‐1.3.5‐triazine, 2‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)‐5‐((hexyl)oxy)phenol (UV‐1577), and 2‐(4,6‐bis‐(2,4‐dimethylphenyl)‐1,3,5‐triazin‐2‐yl)‐5‐(octyloxy)‐phenol (UV‐1164) is present in greenhouse films and soils. TpBD@MIL‐68 has the unique characteristics of a covalent organic framework and a metal–organic framework. TpBD@MIL‐68 exhibited a higher extraction efficiency because of π–π and electrostatic interactions between the benzene ring structure of the TpBD, MIL‐68, and the ultraviolet absorber molecules. The extraction conditions, including the adsorbent dosage, eluent type and dosage, elution time, and the pH of the sample solution, were fully optimized. The extraction efficiency of TpBD@MIL‐68 exceeded 80%. The detection results showed good linearity over a wide range of concentrations (5–5000 µg/L) and low detection limits (0.61–0.94 ng/mL) for target molecules. The practicability of this solid‐phase extraction (SPE)–HPLC method was further evaluated by analyzing greenhouse films and soils, with target recoveries of 80.9%–109.9% and relative standard deviations of less than 8.9%. The as‐synthesized TpBD@MIL‐68 adsorbent exhibited great potential in ultraviolet absorber analysis.

Viticis fructus is the dry fruit of Vitex trifolia L. var. simplicifolia Cham. or Vitex trifolia L., both belonging to the family Verbenaceae. Viticis fructus can grow well in saline alkali lands, and is currently an important industrial raw material for extracting flavones and iridoid glycosides for medicinal use. However, the significance of differences in the chemical components of Viticis fructus from different production areas is not yet clear. Therefore, a sensitive, selective, and accurate UHPLC–ESI–MS/MS method with high selectivity and efficiency was established and validated for simultaneous quantification of nine flavones and one iridoid glycoside in Viticis fructus. A comprehensive quality evaluation of 36 batches of Viticis fructus samples collected from 10 main production areas in China was performed using this method and chemometric analysis. The contents of vitexicarpin in 36 batches of samples were all higher than 0.030% (300 µg/g), which met the requirements of Chinese Pharmacopoeia (2020 edition). However, the contents of the 10 active ingredients from different production areas were quite different. The contents of nine flavones and one iridoid glycoside in Viticis fructus were greatly affected by the growth environment. Humid climatic conditions were relatively favorable for the accumulation of active components in Viticis fructus. The flavone and iridoid glycoside contents were higher in the samples from Shandong, Jiangxi, Guangxi, and Guizhou. Chemometric analysis also showed that vitexicarpin, chrysosplenol D, and agnuside could well represent the total flavones and iridoid glycoside of Viticis fructus for the classification and evaluation of the overall quality of Viticis fructus from different regions. These three representative components can be used as markers to evaluate the quality of Viticis fructus, providing a reliable theoretical and experimental basis for improving the quality standards of Viticis fructus.

The design‐make‐test cycle for drug discovery is highly dependent on the purification of synthesized compounds. Prior to evaluation of suitability, ultrahigh‐performance liquid chromatography is used for an initial standard analysis, where retention times of analytes are measured with a shorter standard gradient method and used to select the appropriate gradients for a final purification method. To circumvent this preliminary screening experiment for small molecule libraries, retention time prediction had been achieved previously by the use of commercial modeling methods. However, these retention time prediction models can have limited applicability when built from smaller datasets and are less effective when constructed from disparate data collected under differing chromatography conditions. Having thousands of measured retention times from high‐throughput physiochemical screening, we sought to leverage these data for the construction of predictive models for a standard preliminary method enabling high‐throughput purification of macrocyclic peptide libraries. Utilizing 4549 analytes and their retention times from high‐throughput physiochemical screening, a structure‐to‐retention‐time model was built using a graph isomorphism network, a form of artificial neural network architecture. Once fitted to high‐throughput screening data, the model was re‐trained with standard gradient method data, a technique known as transfer learning. Through transfer learning, a training set of 80 analytes yielded a neural network model that, when evaluated against a test set of 24 analytes, displays high performance metrics with a coefficient of determination (R²) of 0.82 and mean average error of 0.088 min, or 1.26% of the gradient time. Comparatively, the best commercial quantitative structure‐retention relationship model poorly performed, with an R² of 0.11 and mean average error of 0.202 min. This model has been deployed internally as a Dash app to help democratize the use of the developed models and is being used for selecting purification methods based on analyte structure.

Deciphering the chemical basis of traditional Chinese medicine (TCM) is of far‐reaching significance for revealing its pharmacodynamic mechanism, metabolic transformation, and drug development. However, the complexity of chemical compositions and the large number of isomers in TCM make it difficult to achieve comprehensive detection and identification. Taking Codonopsis Radix as a case, we proposed a reverse molecular assembly (RMA) analysis strategy for rapid discovery of potential new compounds in the complex system of TCM: the paired diagnostic product ions (pDPIs) were designed based on the structural characteristics and characteristic cleavage pathways of taxa‐compounds. First, the reported compounds were categorized into different taxa based on different core structures. Second, pDPIs belonging to a certain taxon were designed according to different core structures, branch chains, and cleavage pathways. Third, the accuracy of pDPIs in positive and negative ion modes was verified by comparing mass spectrometry data, literature reports, and standards. Finally, the RMA analysis strategy was used to accurately identify the chemical components of Codonopsis Radix extract. In this study, 209 compounds were preliminarily characterized, 128 of which are potential new compounds that have not been reported yet in Codonopsis Radix. This study provides an important reference for in‐depth elucidation of the chemical basis of the complex system of TCM.

Reverse fill/flush flow modulation is an effective approach for peak modulation in comprehensive two‐dimensional gas chromatography, and several homemade or commercial solutions have been demonstrated. In terms of configuration, systems with either a fixed bleed capillary or tunable forward or back pressure regulation permit to effectively maintain an optimal modulator channel flow and good modulation performance. In both cases, however, in the up‐to‐date reported works, the modulator channel flow regulation conditions remain constant during the GC run. In this work it was shown that if the objective is to maintain a constant modulator channel flow, constant pressure–resistance regulation conditions can be an issue when the secondary gas chromatography column outlet pressure is not equal to the outlet pressure of the bleed capillary. When the secondary column outlet is connected to a detector, such as, for example, VUV, or to a purged splitter where an elevated constant pressure is applied, which were both tested in this study, in these cases the temperature changes during the GC run impose having to vary the chosen pressure resistance conditions for maintaining a constant modulator channel flow. It was shown, however, that modulator channel flow variation during the GC run appeared minimal when a fixed bleed capillary was used but increased significantly if a tunable auxiliary flow of carrier gas was rather employed. In addition, it was demonstrated through theoretical calculations and experiments that the temperature dependence of the auxiliary carrier gas flow necessary for maintaining a certain constant modulator channel flow is not linear but rather closer to a second‐degree polynomial. While a linear approximation can be sufficient in some cases, in other cases the modulation performance can be impacted more significantly, and thus auxiliary carrier gas flow programming according to a second‐degree polynomial model can be preferred.

In this study, two novel conjugated microporous polymers modified with functional groups were synthesized. Meanwhile, static and dynamic adsorption tests were conducted on the obtained materials. To achieve the best extraction efficiency, the parameters of the pipette‐tip solid‐phase extraction procedure were optimized, including the amount of adsorbent, the type and amount of washing solvent, and the elution solvent. The results demonstrate that the adsorption performance of the sulfonated conjugated microporous polymer is remarkably superior to that of the aminated conjugated microporous polymer. Under the optimal conditions, the linear range for targets was 0.05–10.00 µg/g using this method, the limits of detection were 0.009 µg/g for carbendazim and 0.004 µg/g for thiabendazole, and the recoveries were in the range of 80.7%–108.3% for carbendazim and 87.4%–119.2% for thiabendazole, which was successfully applied to the analysis of target residues in actual samples. In addition, the adsorption capacity of material prepared in this study was superior to that of several commercially available adsorbents. Therefore, a method for the determination of target residues in Ophiopogon japonicus by pipette‐tip solid‐phase extraction coupled with high‐performance liquid chromatography using the material adsorbent was established. This method is important for detecting target residues.

Granaticins and their derivatives are a series of benzoisochromanequinones (BIQs) compounds with remarkable biological activities, but their practical applications have been restricted due to the low separation efficiency of traditional methods. In this work, a high‐speed countercurrent chromatography (HSCCC) method was developed for the first time to separate granaticins from the fermentation broth of Streptomyces vilmorinianum YP1. Considering the similar structures, polarities, and dissociation constants of granaticins, an appropriate solvent system for their complete separation by HSCCC was determined. This system consisted of n‐hexane: ethyl acetate: methanol: water in volume ratios of 2: 5: 3: 4 and 1: 4: 1: 4. Five granaticins with high purity were obtained: a granaticin analogue (29.5 mg); granaticin acid (111.3 mg; purity: 99.2%), MM44785 (49.4 mg; purity: 99.1%), granaticin (0.8 mg; purity: 98.7 %), and granaticin B (73.3 mg; purity: 99.4%) from 2.7 g of crude granaticins extract. The antibacterial activity and stability characteristics of the two main compounds were further evaluated. Granaticin B exhibited excellent antibacterial effects on Gram‐positive bacteria, while granaticin acid showed better thermal stability. This is the first time to develop a general separation strategy for granaticins that are potentially applicable in industry production.

A straightforward and practical 15‐min gas chromatographic method utilizing flame ionization detection has been developed to measure hydrogen cyanide in various matrices. This new approach features a catalyzed two‐stage post‐column reaction that significantly enhances the detection and quantification of hydrogen cyanide. Selecting the right separation column is crucial for accurate analysis. Initial tests with porous layer open tubular columns resulted in significant peak tailing, rendering them unsuitable for trace‐level analysis. Modified polyethylene glycol stationary phases also exhibited strong peak tailing in addition to producing artifact peaks. In contrast, a polydimethylsiloxane‐based column with a very low phase ratio (β = 10) demonstrated excellent analytical performance, including peak symmetry and inertness. The analytical approach achieved a minimum detection limit of 50 parts per billion (ppb, v/v) without preconcentration and a linear range from 0.05 to 200 parts per million (ppm, v/v). At a concentration level of 20 ppm (v/v), the RSD at the 95% confidence level was less than 1% (n = 10), and at a concentration level of 1 ppm (v/v), the RSD at the 95% confidence level was less than 3% (n = 10) under the established conditions. The method's effectiveness has been validated through real‐life applications, including analyzing hydrogen cyanide in fruit seeds and the headspace of untreated water samples.

Although traditional Tibetan medicine is a valuable source for the discovery of novel lead compounds, the isolation of structural analogs from natural sources remains a challenge in the field of separation science. The Tibetan medicine Gentiana szechenyii (GC) is widely to treat various types of inflammation and upper respiratory tract infections. Despite its strong medicinal value, a complex purification process has limited investigations into its chemical composition. Therefore, in this study, a novel off‐line two‐dimensional supercritical fluid chromatographic (2D‐SFC) method was developed and successfully applied to the efficient separation and purification of complex compounds and structural analogs from GS. Initially, the crude GS sample was pretreated using a binary medium‐pressure liquid chromatography system to obtain the target fraction (Fr16, 1.0 g). A novel propyl urea and phenyl/tetrazole stationary phases off‐line 2D‐SFC system was then developed and applied for the separation and purification of Fr16. Consequently, five polyphenolic compounds were successfully isolated with purities of >95%. The obtained results demonstrate the potential of off‐line 2D‐SFC for maximizing the discovery of novel structural analogs and isomers, thereby providing a theoretical basis for the further exploitation of natural products.

A novel, simple capsule phase microextraction combined with high‐pressure liquid chromatography coupled with ultraviolet detection analytical method was developed for the simultaneous determination of organic monomers that can be released from dental resins [bisphenol‐A (BPA), bisphenol A glycerolatedimethacrylate (Bis‐GMA), triethylene glycol dimethacrylate (TEGDMA), and urethane dimethacrylate (UDMA)] in cola drinks. The critical parameters that affect the extraction, such as the selection of the capsule type and size, extraction time, type, and volume of elution solvent, stirring rate during the extraction, and desorption time, were optimized. The method was subsequently validated in terms of selectivity, linearity, accuracy, precision, and robustness and showed satisfactory results. The limits of detection and quantitation were equal to 0.06 and 0.2 ng/µL, respectively, and the recoveries ranged between 93.3% and 106.9%. The method was employed in the determination of monomers released from cola drinks. For this purpose, cola refreshments were incubated with dental resins for 24 h and 7 days, and the proposed method was successfully used for monitoring the release in cola samples.

Recent concern about the impact of environmental preservation and the health of living beings has opened new avenues for scientific research. In this context, contemporary analytical chemistry has been marked by the development of green analytical methodologies, which aim to reduce the use of toxic reagents and minimize the environmental impact of analytical processes. Progress in this area involves the optimization of sample preparation techniques and the use of new functional materials, which contribute to a more sustainable and efficient analysis. Among these methodologies, miniaturized sample preparation techniques stand out, as they use smaller volumes of solvents and offer high sensitivity and selectivity. The use of advanced materials, such as molecularly imprinted polymers, MOFs, and conductive polymers, has driven innovation in analytical procedures regarding complex matrices, including environmental, food, and biological samples. These materials offer high selectivity and stability, improving efficiency in the extraction and detection of specific analytes. This review explores the integration of sustainable and green methodologies. It critically highlights applications and evaluates them using the Analytical Greenness Metric for Sample Preparation, based on publications from the past 6 years.

The interest toward greener and more sustainable chemical processes is constantly growing, especially in chemical industries, where there is an urgent need to reduce the waste on one hand, and to replace not environmentally friendly organic solvents, on the other. One of the current challenges in industrial processes is the depletion of the psychoactive cannabinoid tetrahydrocannabinol (THC) from hemp extracts. Indeed, current legislations impose that THC in hemp products must meet defined concentration limits or, in some cases, it must be completely removed. In the present study, the continuous depletion of THC has been performed through simulated moving bed chromatography operated with a fully green mobile phase, made of water and ethanol. This process permits to overcome the limits and drawbacks of available purification methods, based on toxic solvents and traditional single column chromatography.

Qubai Babuqi Tablets (QBBBQT) is a traditional Chinese medicine compound preparation. It is mainly used in treating vitiligo, with the effect of activating pulse‐beat and regulating blood condition. However, the chemical composition of QBBBQT has not been reported, and it was difficult to determine its active and toxic components. In this study, a simple and efficient method was established to characterize the chemical constituents of the alcohol extract of QBBBQT. Which used ultra‐high‐performance liquid chromatography quadrupole‐orbitrap‐mass spectrometry to match experimental MS² with characteristic ions and neutral losses for rapid analysis and identification of its chemical composition. Finally, a total of 106 chemical components were identified, including 47 flavonoids, 13 coumarins, 21 organic acids, 11 diarylheptanes, four saccharides, and 10 others. This method can be used for the systematic and rapid analysis of the chemical components in QBBBQT, which is of great significance for the study of its pharmacodynamic material basis and quality control.

Herein, we present a sensitive analytical method utilizing Materials Institute Lavoisier (MIL)‐68(Al)‐coated frosted glass rods (MIL‐68(Al)@FGR) coupled with ultra‐high‐performance liquid chromatography for detecting trace tetracycline (TC) antibiotics in food matrices. The synthesized coating was thoroughly characterized through field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, and Fourier‐transform infrared spectroscopy analyses. Systematic optimization of critical parameters, including extraction time, sample pH, formic acid concentration, and desorption time achieved optimal extraction efficiency. The developed method exhibited a wide linear range (3–70 ng/mL) with low detection limits (0.1–0.3 ng/mL) for target analytes. Practical application to spiked food samples demonstrated satisfactory recoveries of 75.2%–115.1% across milk, chicken, and egg matrices, accompanied by precise relative standard deviations of ≤8.4%. The MIL‐68(Al)@FGR‐based approach shows exceptional resistance to matrix interference and detection sensitivity, establishing an effective strategy for monitoring TC residues in complex food samples.

A novel and accurate ultra‐high performance liquid chromatography (UHPLC) method combined with UV detector was developed for the simultaneous determination of 10 fat‐soluble vitamins (retinyl acetate, retinyl palmitate, beta carotene, alpha tocopherol, alpha tocopheryl acetate, alpha tocopheryl acid succinate, ergocalciferol, cholecalciferol, phytonadione, and menaquinone‐7) in multivitamin with mineral capsules. The chromatographic separation was achieved on a Waters XBridge Sheild C18 (100 × 2.1 mm, 1.7 µm) column. The mobile phase comprised of 0.1% formic acid (v/v) in water and 0.1% formic acid in acetonitrile (v/v) delivered in a gradient mode. An enhanced and simple sample preparation procedure involving enzyme digestion of the gel coating of the capsules and ultra‐sonication was developed compared to the complex and time‐consuming saponification methods. The method was validated to fulfill International Conference on Harmonization (ICH) requirements and included specificity, linearity, accuracy, precision, and robustness. The linearity of the method was excellent (R² > 0.999), the RSD for the precision was < 5% and the recovery of the vitamins was in the range of 99.2%–101.9%, demonstrating that the method is suitable for analysis of fate‐soluble vitamins in multivitamin capsules. The developed method could be incorporated into the USP‐NF Multivitamin with minerals capsules monograph.

Risdiplam is a new therapeutic agent developed to treat spinal muscular atrophy (SMA), a genetic neurodegenerative disease caused by mutations in the SMN1 gene. Unlike previous invasive therapies, risdiplam offers the advantage of oral administration, significantly improving patient comfort and accessibility. The review provides information on an SMA historical overview, breakthrough therapies of the development, and design of the methods used to treat SMA. We then focus on its structure and physicochemical properties. The analysis of risdiplam concentrates on developing improved analytical methods for the precise quantification of risdiplam and its metabolites by high‐performance liquid chromatography with mass spectrometry in biological samples using octadecyl stationary phases. For sample preparation, only the protein precipitation method was used. Challenges associated with the risdiplam analytics include developing a highly sensitive and selective method in biological matrices and dealing with potential interferences from the biological matrix. Future research should focus on improving analytical methods, investigating metabolite activity, and expanding our knowledge of its long‐term effects.

Deep eutectic solvents have attracted increasing attention in enantioseparation, but only a few studies focus on the development of deep eutectic solvents as the sole chiral selector. In this work, a one‐pot synthetic method was used to prepare a deep eutectic solvent based on a polysaccharide chiral selector (maltodextrin) as the sole chiral selector in capillary electrophoresis. Six azole antifungal drugs were used as model drugs to investigate the chiral resolution ability of the maltodextrin‐glycerol. Compared to native maltodextrin, the deep eutectic solvents exhibited the more excellent enantioselectivity towards model drugs. Some key factors affecting separation such as maltodextrin concentration, glycerol concentration, buffer pH and separation voltage were investigated. In addition, ultraviolet spectroscopy method and Statistical Product and Service Solutions analysis were adopted to investigate the enhanced chiral recognition mechanism. It is the first time that polysaccharide‐based deep eutectic solvents was developed as a favorable chiral selector in capillary electrophoresis, and this research strategy has paved a new way for developing novel chiral materials.