Separation Column Research Articles

The Structure Characterization of Polysaccharides from Codonopsis pilosula and the Structure-activity Relationship with Immune-regulation on THP-1 Cells.

In recent years, polysaccharides from Codonopsis pilosula (CPs) have received increasing attention for their excellent behaviors in immune-regulation. However, the relationship between the structure and immunomodulatory activity has rarely been reported. In this work, four fractions purified from crude CPs (CPW, CPS0.2, CPS0.5, CPS1) by chromatographic column separation were explored with both structure and immunomodulatory effects by THP-1 cells. The results showed that the monosaccharide composition, chain conformation, molecular weight (Mw) and aggregated state of CPs were different. At the same time, the immunomodulatory effects of CPs were also varied depend on structure differences, as indicated by the released cytokines of TNF-α and IL-1β by LPS-induced THP-1 cells. Finally, we summarized and concluded that the spherical structure and smaller particle size of CPs were the key factors attributed to better immune-enhancing effects. The results showed that the monosaccharide combination differences of polysaccharides might lead to anti-inflammatory or pro-inflammatory activity. Moreover, the higher percentage of glucose, the relatively large particle size, as well as the extended chain conformation of CPs might be the key factors attributed to better immune-enhancing effects. This study aims to provide a theoretical basis for establishing the structure-activity relationship of CPs.

A New LC-MS/MS-Based Method for the Simultaneous Detection of α-Tocopherol and Its Long-Chain Metabolites in Plasma Samples Using Stable Isotope Dilution Analysis

Background: Our study presented a novel LC-MS/MS method for the simultaneous quantification of α-tocopherol (α-TOH) and its phase II metabolites, α-13′-COOH and α-13′-OH, in human serum using deuterium-labeled internal standards (d6-α-TOH, d6-α-13′-COOH, d6-α-13′-OH). Methods: The method addresses the analytical challenge posed by the significantly different concentration ranges of α-TOH (µmol/L) and its metabolites (nmol/L). Previous methods quantified these analytes separately, which caused an increase in workflow complexity. Results: Key features include the synthesis of stable isotope-labeled standards and the use of a pentafluorophenyl-based core-shell chromatography column for baseline separation of both α-TOH and its metabolites. Additionally, solid phase extraction (SPE) with a HybridSPE® material provides a streamlined sample preparation, enhancing analyte recovery and improving sensitivity. By utilizing deuterium-labeled standards, the method compensates for matrix effects and ion suppression. This new approach achieves precise and accurate measurements with limits of detection (LOD) and quantification (LOQ), similar to previous studies. Calibration, accuracy, and precision parameters align well with the existing literature. Conclusions: Our method offers significant advantages in the simultaneous analysis of tocopherol and its metabolites despite concentration differences spanning up to three orders of magnitude. In contrast to earlier studies, which required separate sample preparations and analytical techniques for tocopherol and its metabolites, our approach streamlines this process. The use of a solid-phase extraction procedure allows for parallel sample preparation. This not only enhances efficiency but also significantly accelerates pre-analytical workflows, making the method highly suitable for large-scale studies.

Phytochemical Analysis and Antioxidant, Antimicrobial, and Antibiofilm Effects of a New Himalayan Lichen Placidium deosaiense Usman and Khalid Growing in Pakistan

Phytochemical composition and antimicrobial, antibiofilm, and antioxidant effects of a newly described Himalayan lichen Placidium deosaiense Usman and Khalid growing in Pakistan were investigated. HPLC–DAD methods were used for identification of secondary metabolites in acetone and methanol extracts. The total phenolics content was measured using a spectrophotometric method. The study investigated the antioxidant (DPPH-scavenging activity assay and reducing-power assay), antibacterial (minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)), and antibiofilm (inhibition of biofilm formation and reduction in mature biofilm) activities of extracts of the lichen P. deosaiense and isolated parietin. The chemical constituents olivetol, olivetolic acid, haematommic acid, fallacinol, and parietin were identified as major compounds in the tested extracts of the lichen. Parietin was isolated from the acetone extract on a separation column. The methanol extract had higher values of TPC (21.67 mg GAE/g) than the acetone extract. Isolated parietin showed the best antioxidant activity measures, according to the DPPH-scavenging activity assay (IC50 = 51.616 μg/mL) and reducing-power assay. Although the extracts showed the best antibacterial activity (especially against Proteus mirabilis ATCC 12453), parietin demonstrated superior antibiofilm activity (especially against Staphylococcus aureus ATCC 25923). This is the first report on the phytochemical composition of the lichen Placidium deosaiense and the first description of the chemical composition of some of the 45 species of the genus Placidium. This research will pave the way for further exploration of new activities of this lichen and its metabolites, which are important for medicine and pharmacy.

Development of the Separation Column’s Temperature Field Monitoring System

Oil is one of the main resources used by all countries in the world. The ever-growing demand for oil and oil products forces oil companies to increase production and refining. In order to increase net profit, oil producing companies are constantly upgrading equipment, improving oil production technologies, and preparing oil for further processing. When considering the elements of primary oil refining in difficult conditions, such as hard-to-reach or in remote locations, developers face strict limitations in energy resources and dimensions. Therefore, the use of traditional systems causes a number of difficulties, significantly reducing production efficiency. In this study, the authors solve the problem of improving the characteristics of the oil separation process. In their work, the authors analyzed the separation columns of primary oil distillation, identified the shortcomings of the technological process, and searched for technological solutions. Having identified the lack of technical solutions for monitoring the state of the temperature field of the separation column, the authors developed their own hardware–software complex for monitoring the separation column (RF patents No. 2020665473, No. 2021662752 were received). The complex was tested and successfully implemented into production. The study provides an assessment of the economic efficiency of implementation for a year and a forecast of the economic effect for 10 years.

Optimizing Low-Cost Gas Analysis with a 3D Printed Column and MiCS-6814 Sensor for Volatile Compound Detection.

This paper explores an application of 3D printing technology on the food industry. Since its inception in the 1980s, 3D printing has experienced a huge rise in popularity. This study uses cost-effective, flexible, and sustainable components that enable specific features of certain gas chromatography. This study aims to optimize the process of gas detection using a 3D printed separation column and the MiCS-6814 sensor. The principle of the entire device is based on the idea of utilizing a simple capillary chromatographic column manufactured by 3D printing for the separation of samples into components prior to their measurement using inexpensive chemiresistive sensors. An optimization of a system with a 3D printed PLA block containing a capillary, a mixing chamber, and a measuring chamber with a MiCS-6814 sensor was performed. The optimization distributed the sensor output signal in the time domain so that it was possible to distinguish the peak for the two most common alcohols, ethanol and methanol. The paper further describes some optimization types and their possibilities.

Engineering Trifluoromethyl Groups in Porous Coordination Polymers to Enhance Stability and Regulate Pore Window for Hexane Isomers Separation.

Effective separation of hexane (C6) isomers is critical for a variety of industrial applications but conventional distillation methods are energy-intensive. Adsorptive separations based on porous coordination polymers (PCPs) offer a promising alternative due to their exceptional porosity and tunable properties. However, there is still an urgent need to develop PCPs with high stability and separation performance. This study investigates how substituting a methyl (-CH3) group with a trifluoromethyl (-CF3) group can regulate pores and hydrophobicity in PCPs. This precise adjustment aims to enhance stability and improve the kinetic separation performance of hydrophobic C6 isomers by considering the size and hydrophobicity of the trifluoromethyl group. Two isostructural PCPs with pcu topology, PCP-CH3 and PCP-CF3, were synthesized to vary pore diameters and hydrophobicity based on the presence of -CH3 or -CF3 groups. PCP-CF3 showed greater stability in water compared to PCP-CH3. While PCP-CH3 had high adsorption capacities, it lacked selectivity, whereas PCP-CF3 demonstrated improved selectivity, particularly in excluding dibranched isomers. Dynamic column separation experiments revealed that PCP-CF3 could selectively adsorb linear and monobranched isomers over dibranched isomers at room temperature. These findings highlight the potential of fluorine-modified PCPs for efficient isomer separation and underscore the importance of stability improvement strategies.

Triclinic polymorph of bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] tetrachloridocadmium(II)

The crystal structure of the title organic–inorganic hybrid salt, (C13H12N3)2[CdCl4], (I), has been reported with four molecules in the asymmetric unit in a monoclinic cell [Vassilyeva et al. (2021). RSC Advances, 11, 7713–7722]. While using two different aldehydes in the oxidative cyclization–condensation involving CH3NH2·HCl to prepare a new monovalent cation with the imidazo[1,5-a]pyridinium skeleton, a new polymorph was obtained for (I) in space group P 1 and a unit cell with approximately half the volume of the monoclinic form. The structural configurations of the two crystallographically non-equivalent organic cations as well as the geometry of the moderately distorted tetrahedral CdCl4 2– dianion show minor changes. In the crystal, identically stacked cations and tetrachlorocadmate anions form separate columns parallel to the a axis. The loose packing of the anions leads to a minimal separation of approximately 9.53 Å between the metal atoms in the triclinic form versus 7.51 Å in the monoclinic one, indicating that the latter is packed slightly more densely. The two forms also differ by aromatic stacking motifs. Similar to the monoclinic polymorph, the triclinic one excited at 364 nm shows an intense unsymmetrical photoluminescent band with maximum at 403 nm and a full width at half maximum of 51 nm in the solid state.

Innovative fluidized bed flotation column for fine particle separation

Flotation columns are extensively utilized to separate fine mineral particles. In highly turbulent environments, the increased collision efficiency between bubbles and particles can lead to improved flotation efficiency of fine particles. The fluidized bed flotation column (FBFC), a new type of flotation equipment, improves the separation efficiency of fine particles by creating a highly turbulent environment in the fluidized zone through the addition of solid particles. This paper investigated the fluidization characteristics, bubble, and gas hold up of the FBFC, along with the flotation efficiency of fine quartz particles. Experimental results showed that introducing gas enhanced the fluidization process in the fluidized bed. The fluidized zone facilitated the fragmentation of bubbles into smaller ones. With increasing liquid velocity, the bubble diameter decreases before subsequently increasing, while the gas holdup initially rises and then declines. The flotation efficiency of fine quartz particles is superior in FBFC with added particles compared to those without added particles. The flotation efficiency of fine particles increases with the rise in both liquid velocity and gas velocity.

Effect of binary porogen mixtures on polymer monoliths prepared by gamma-radiation initiated polymerization

Gamma-radiation initiated polymerization is an easy-to-use and simple technique for the preparation of porous polymer monoliths widely used as active materials in separation columns. Herein, binary porogen mixtures of ethyl acetate/acetone/acetonitrile with methanol were used to synthesize diethylene glycol dimethacrylate monoliths with this technique. Systematic studies have been performed to determine the effect of the composition of the solvent mixture on the morphology and the reaction kinetics, including the growth mechanism and the growth rate. The irradiation dose-dependent conversion profiles showed that with binary solvents the polymerization is much faster than with the same compounds used as single solvents. Depending on the type and the composition of the solvent one-, two- and three-dimensional, and fractal growth mechanisms were identified.

Single-pot extractive double divided wall column for Acetonitrile, Ethanol, and water Separation: Design and control

An integrated single-pot double divided wall column (DDWC) process is designed for separating acetonitrile, ethanol and water into its constituent pure components using dimethyl sulfoxide (DMSO) as the homogenous extractive entrainer. Comparison with the recently reported side-stream extractive distillation (SSED) design with three columns shows the single-pot process to be more cost-effective and energy-efficient. The SSED process has a Total Annualized Cost (TAC) that is higher by 9.91% and an energy consumption that is higher by 7.27%. Also, a decentralized temperature inferential control system is shown to effectively reject large throughput and moderate feed composition changes to establish the controllability of the proposed design. The developed single-pot process is thus a promising alternative, particularly for space-constrained production facilities.

Measurement of atmospheric amines and aminoamides by column adsorption/extraction and hydrophilic liquid chromatography-electrospray-tandem mass spectrometry.

Sampling and chromatography-mass spectrometry methods were investigated to measure atmospheric amines and aminoamides. Amines and their amide derivatives play significant roles in new particle formation (NPF) in the atmosphere, especially diamines and aminoamides have higher NPF potentials compared to monoamines. For amine sampling, silica gel tube collection and formic acid extraction gave good overall recoveries (>93 ± 8%) for mono-, di-, tri-, tetramines, and aminoamides. Two chromatography methods were subjected to analyze the extracted amines. One involved direct analysis using hydrophilic interaction liquid chromatography with carboxyl or diol group functioned separation column (carboxyl-HILIC or diol-HILIC), and the other utilized derivatization with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) and subsequent reversed-phase chromatography (HPLC). Separated amines were detected by electrospray ionization and tandem mass spectrometry in both cases. DBD-F-HPLC method provided good sensitivity for mono- and all polyamines (limit of detection (LOD) < 4.6nM, relative standard deviation (RSD) for 100nM < 9.2%). However, aminoamides could not be detected by DBD-F-HPLC. Carboxyl-HILIC provided good sensitivities for mono- and diamines and aminoamides (LOD < 1.6nM, RSD < 4.8%). Forest air measurement was performed and data obtained by carboxyl-HILIC and DBD-F-HPLC showed good agreement for 1,3-diaminopropane, 1,4-diaminobutane (putrescine) and 1,5-diaminopentane (cadaverine) (R2 = 0.9215-0.9739, n = 7-14). Carboxyl-HILIC method was the best for the amine analysis, and combination with silica gel tube sampling provides atmospheric monitoring available. The developed method can be used not only to study atmospheric chemistry of diamines and aminoamides but also to analyze flavor/odor of foods, flowers and wastes.

Determination of deoxynivalenol and metabolites in maize samples by LC-MS/MS

In Vietnam, the regulation QCVN 8-1:2011/BYT has been issued to control mycotoxin content in food products. However, there are currently no regulations or studies on their derivatives and metabolites. Deoxynivalenol-3-glucoside (D3G) and two acetylated derivatives of deoxynivalenol (DON), namely 15-acetyldeoxynivalenol (15-AcDON) and 3- acetyldeoxynivalenol (3-AcDON), have been frequently detected in naturally contaminated grains such as wheat, barley, and corn. This study developed and applied a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine deoxynivalenol (DON) and its metabolites, including deoxynivalenol-3-glucoside (D3G), 3- acetyldeoxynivalenol (3-AcDON), and 15-acetyldeoxynivalenol (15-AcDON) in maize. The instrumental conditions comprised a C18 HSS SB (150 mm &amp;times; 2.1 mm &amp;times; 1.7 &amp;micro;m) column for separation and an MS/MS detector in positive and negative electrospray ionization (ESI) source, employing multi-reactive ion monitoring mode, with an injection volume of 2 &amp;micro;L. The method has been fully validated and meets the performance requirements of AOAC, demonstrating high specificity. The linearity range was established from 100 &amp;micro;g/kg to 1000 &amp;micro;g/kg, with a method detection limit (MDL) of 30 &amp;micro;g/kg. The repeatability and recovery rates were determined to be between 1.45% to 4.31% and 90% to 110%, respectively. The validated method was applied to analyze 50 maize samples. Deoxynivalenol (DON) was detected in 10 samples (20%), while deoxynivalenol-3-glucoside (D3G), 3- acetyldeoxynivalenol (3-AcDON), and 15-acetyldeoxynivalenol (15-AcDON) were not detected in any of the samples.

Preparation of alkyl microporous organic network-based capillary column for an efficient gas chromatographic separation of position isomers.

The large surface area, excellent thermal stability and easy modification make microporous organic networks (MONs) good candidates in the field of gas chromatography (GC). Due to the limited species and highly conjugated networks of MONs, their applications are still in infancy and restricted. To accelerate their developments and to enrich their types in GC, here we report the first example of synthesizing alkyl MON and its capillary column for GC separation of position isomers. Linear 1,8-dibromooctane is used as the alkyl monomer instead of traditional aromatic ones to construct novel alkyl MON to decrease the inherent conjugated characteristic of MONs. The alkyl MON exhibits good thermal stability (up to 350°C), large surface area (1173m2g-1), and non-polar character, allowing good resolution for alkanes, alkyl benzenes, alcohols, ketones, and diverse position isomers, including dichlorobenzene, trichlorobenzene, bromotoluene, nitrotoluene, methylbenzaldehyde, and ionone with the limits of detection (0.003mgmL-1) and limits of quantitation of (0.10mgmL-1). The in situ growth-prepared alkyl MON column demonstrates remarkable duration time and precisions for the retention relative standard deviations, (RSDs%, intra-day, n=7), 0.06%-0.53% (intra-day, n=7), and 2.87%-10.59% (column-to-column, n=3). In addition, the fabricated alkyl MON-coated capillary column offers better resolution than three commercial GC columns for the resolution of methylbenzaldehyde, bromotoluene, and chlorotoluene isomers. This work reveals the practicability for synthesizing alkyl MONs and demonstrates their prospects for position isomers separation.

Experiences with the infra-acetabular screw placement technique in acetabular fracture surgery

To investigate the application experiences and effectiveness of the infra-acetabular screw (IAS) placement technique in acetabular fracture surgery. A clinical data of 34 patients with complex acetabular fractures with anterior and posterior columns separation, who were admitted between January 2019 and October 2023 and treated with IAS fixation, was retrospectively analyzed. There were 23 males and 11 females with an average age of 55.3 years (range, 18-78 years). The acetabular fractures caused by traffic accident in 20 cases, falling from height in 12 cases, crushing injury in 1 case, and bruising with a heavy object in 1 case. According to the Letournel-Judet classification, there were 7 cases of anterior column fracture, 8 cases of anterior wall/column plus posterior hemi-transverse fracture, 2 cases of T-shaped fracture, and 17 cases of both-column fracture. The time from injury to surgery was 4-21 days (mean, 8.6 days). The time of IAS placement and the intraoperative blood loss were recorded. After surgery, the X-ray film and CT scan were re-examined, and the modified Matta score was used to assess the quality of fracture reduction. The trajectory of IAS in the channel was analyzed based on CT scan, and the screw length was measured. During follow-up, the fracture healing was observed and the hip function was assessed according to the modified Merle d'Aubigné-Postel scoring system at last follow-up. The IAS was successfully implanted in all 34 patients. The length of IAS ranged from 70 to 100 mm (mean, 86.2 mm). The time of IAS placement ranged from 10 to 40 minutes (mean, 20.7 minutes). The intraoperative blood loss ranged from 520 to 820 mL (mean, 716.8 mL). All patients were followed up 8-62 months (mean, 21.8 months). After surgery, 4 patients developed lateral femoral cutaneous nerve injury, 2 developed popliteal vein thrombosis of the lower extremity, 3 developed incision infection, and no surgical complication such as arteriovenous injury or obturator nerve palsy occurred. At last follow-up, the hip function was rated as excellent in 14 cases, good in 13 cases, fair in 4 cases, and poor in 3 cases according to the Merle d'Aubigné-Postel scoring system, with an excellent and good rate of 79.41%. Imaging re-examined showed that the quality of fracture reduction was rated as excellent in 9 cases, good in 19 cases, and poor in 6 cases according to the modified Matta score, with an excellent and good rate of 82.35%; and 25 (73.53%) IAS trajectories were located in the channel. All fractures obtained bony union, and the healing time was 12-24 weeks (mean, 18 weeks). During follow-up, there was no loosening or fracture of the plate and screws. IAS placement technique can effectively strengthen internal fixation and prevent fracture re-displacement, making it a useful adjunct for treating complex acetabular fractures with anterior and posterior columns separation.

Determination and evaluation of canthaxanthin and β-apo-8’-carotenoid ethyl ester in chicken eggs and meat in Tianjin

Canthaxanthin and β-apo-8’-carotenoid ethyl ester are widely used as feed additives in poultry feed for enhancing the color of poultry products. The excessive intake of the two colorants can cause health damage. According to the European Food Safety Authority (EFSA), the acceptable daily intake (ADI) of canthaxanthin and β-apo-8’-carotenoid ethyl ester are 0.03 mg/kg·bw and 0.015 mg/kg·bw, respectively. Ultra-high-performance liquid chromatography-diode array detector (UPLC-DAD) was used to determine two colorants in chicken eggs and meat. A PRiME HLB solid-phase extraction cartridge was used to extract and clean-up the sample. BEH C18 column was used as the separation column, with water containing 0.1% formic acid and acetonitrile as the mobile phase. The limit of detection (LOD) was 0.05 mg/kg, and the limit of quantification (LOQ) was 0.1 mg/kg. The recoveries were between 90% and 104%. The daily intake of two colorants in chicken eggs and meat was evaluated based on the detection data, food consumption data and weight data of the population. The mean estimated daily intake (EDI) values of canthaxanthin through chicken eggs and meat were 1.09 µg/(kg·bw·d) and 0.013 µg/(kg·bw·d), respectively. The mean EDI value of β-apo-8’-carotenoid ethyl ester through eggs was 0.44 µg/(kg·bw·d). The results showed that eggs were the main contributor to the daily intake of two colorants. The mean hazard quotients (HQ) values of two colorants through chicken eggs and meat was within a safe range.

Fractional distillation of waste plastic pyrolysis oil for isolating narrow hydrocarbons cuts

Pyrolysis of polyolefins generates a large amount of olefins, which can serve as a valuable feedstock for the synthesis of chemicals. Nevertheless, their effective utilization requires refining owing to their diverse carbon distribution. This study performed a comprehensive GC×GC analysis of pyrolysis oils derived from waste polypropylene (PP) and waste high-density polyethylene (HDPE). The chemical composition of PP pyrolysis oil exhibited a high content of iso-olefins, whereas HDPE pyrolysis oil contained mainly alpha-olefins. Experimental batch distillation of PP pyrolysis oil yielded narrow hydrocarbon cuts with iso-olefins content exceeding 70 wt%. In contrast, distillation of HDPE resulted in cuts with more than 25 wt% alpha-olefins content. To perform ASPEN simulations, the physical properties (density, viscosity) of the oil were determined, two ways for obtaining boiling curves (ASTM D2887 and ASTM D86) were compared and two property methods (Peng-Robinson and Soave-Redlich-Kwong) were compared. It was concluded that the ASTM D2887 boiling curve and the Peng-Robinson property method present better experimental agreement for pyrolysis oils using the Theil’s Inequality Coefficients test. Based on the validated batch simulation, continuous distillation process schemes for isolating narrow carbon cuts in the refinery atmospheric tower indicate that a side draw configuration provides a better yield of (19.1 wt%) compared to a dedicated separate distillation column of (11.9 wt%) for the same number of trays, while the dedicated column allows the possibility to achieve higher purity.

Precise target capture and the dynamic separation of Sn(IV) in highly acidic media by combining N and P donor covalent organic framework silica-based composite adsorbents

A silica-based adsorbent (P507@COF-TpAzo/SiO2) with nitrogen and phosphorus donors was prepared for industrial separation and recovery of Sn(IV) by in-situ growth of covalent organic framework (COF) on a silica substrate combined with vacuum impregnation. The materials were tested and analyzed by the scanning electron microscope (SEM), X-ray diffraction (XRD) and other characterization techniques, which demonstrated that the adsorbent has an enormous specific surface area, excellent heat resistance, and a regular morphological structure. The static experimental results showed that the adsorbent displayed remarkable selectivity for Sn(IV) in high HCl and HNO3 concentration environments, with excellent kinetics (∼60 min) and outstanding adsorption capacities (60.02 mg/g in 3 M HCl, 92.59 mg/g in 3 M HNO3) in different media at 3 M acidity. Cycle performance testing demonstrated that the adsorbent exhibited excellent stability (cycle times ≥8). Analysis using Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) showed that the synergistic adsorption results of N and P were reflected, mainly by the synergistic complexation of P=O and N=N-C. The potential sites for the adsorption of the adsorbent towards Sn(IV) were predicted by density functional theory (DFT) calculations, and the adsorbent demonstrated a more stable binding energy with Sn(IV). Finally, dynamic separation and efficient enrichment (>210) of Sn(IV) in highly acidic wastewater were realized by designing a penetrating column separation process. P507@COF-TpAzo/SiO2 satisfied the requirements of the dynamic adsorption experiments, bridging the research gap of dynamic separation, and provides a new strategy for the industrial removal and recovery of Sn(IV), as well as a way for environmental protection and industrial green production.

Remediation of plastic waste generated during the COVID-19 pandemic: A conceptual process design of pyrolysis using polyethylene, polypropylene, polystyrene based polymers

During the COVID-19 pandemic, the increase in plastic-based personal protective equipment has raised concerns about managing medical waste and protecting the environment. This study highlights the need for effective waste management strategies by creating a conceptual process flow diagram and investigating thermal treatment methods like pyrolysis as potential solutions. Using computational modeling and process optimization, the study examines different polymer blends, including High-Density Polyethylene (HDPE), Polystyrene (PS), and Polypropylene (PP), to understand how they behave during pyrolysis and the yields they produce. Two pyrolysis schemes have been developed to handle various polymer blends. In Scheme 1, the liquefied polymer is preheated and then pyrolyzed in a reactor, producing a vapor stream and a residue stream (carbon). The vapor stream is cooled to enhance liquid oil production and then is separated in a distillation column to isolate liquid oil from pyrogas. Scheme 2 follows a similar process but converts a significant portion of liquid hydrocarbons to gas in the distillation column, requiring further gas processing in a one-stage separator column. The results show that temperature significantly impacts liquid yield, with specific temperature ranges leading to increased yield. Additionally, the composition of the polymers and the rate at which the material is fed into the process affect the yields, with specific blends showing promise for higher liquid yield. This study emphasizes the importance of accurate process modeling to optimize the operational parameters and improve the economic viability of plastic pyrolysis technology presenting a promising opportunity to convert plastic waste into valuable resources.

Breathomics: may it become an affordable, new tool for early diagnosis of non-small-cell lung cancer? An exploratory study on a cohort of 60 patients.

Analysis of breath, specifically the patterns of volatile organic compounds (VOCs), has shown the potential to distinguish between patients with lung cancer (LC) and healthy individuals (HC). However, the current technology relies on complex, expensive and low throughput analytical platforms, which provide an offline response, making it unsuitable for mass screening. A new portable device has been developed to enable fast and on-site LC diagnosis, and its reliability is being tested. Breath samples were collected from patients with histologically proven non-small-cell lung cancer (NSCLC) and healthy controls using Tedlar bags and a Nafion filter attached to a one-way mouthpiece. These samples were then analysed using an automated micro portable gas chromatography device that was developed in-house. The device consisted of a thermal desorption tube, thermal injector, separation column, photoionization detector, as well as other accessories such as pumps, valves and a helium cartridge. The resulting chromatograms were analysed using both chemometrics and machine learning techniques. Thirty NSCLC patients and 30 HC entered the study. After a training set (20 NSCLC and 20 HC) and a testing set (10 NSCLC and 10 HC), an overall specificity of 83.3%, a sensitivity of 86.7% and an accuracy of 85.0% to identify NSCLC patients were found based on 3 VOCs. These results are a significant step towards creating a low-cost, user-friendly and accessible tool for rapid on-site LC screening. ClinicalTrials.gov Identifier: NCT06034730.

Rapid and simultaneous determination of ultrashort-, short- and long- chain perfluoroalkyl substances by a novel liquid chromatography mass spectrometry method

Per- and Polyfluoroalkyl Substances (PFAS) are a group of persistent organic pollutants that have received considerable attention from public and regulatory groups. Due to regulations of long-chain PFAS, the use of short-chain and ultrashort-chain PFAS is rapidly growing. Thus, there is an urgent need to develop quantitative methods for determining PFAS with different chain lengths in various environmental matrices. This study introduces an innovative liquid chromatography-mass spectrometry (LC-MS) system combining large volume injection (LVI) and online solid phase extraction (SPE). This system incorporates three columns: a reverse-phase (RP) column, a weak anion exchange (WAX) trap column, and a hybrid HILIC/ion-exchange (HILIC/IE) column, controlled by two valves. With valve switching, ultrashort-chain PFAS that are not retained by the RP column are enriched by the trap column, while other PFAS are separated by the RP column. The trapped ultrashort PFAS are then transferred to the HILIC/IE column for further separation. The LVI significantly enhances the method's sensitivity, allowing for rapid and simultaneous determination of ultrashort-, short- and long- chain PFAS in aqueous samples. The matrix effects from various environmental samples were evaluated, and the results indicate that this unique LC-MS method is suitable for analyzing all chain-length PFAS in various matrices, including surface water, sewage effluent, and seawater. Finally, this novel LC-MS method was applied to quantify PFAS in various water samples.