Filter Plate Research Articles

B-161 Liquid chromatography/mass spectrometry analysis of ethyl glucuronide and ethyl sulfate using a perfluorophenyl stationary phase

Abstract Background Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are minor metabolites of ethanol that are excreted in urine. These two metabolites are often tested for to determine if an individual has recently consumed alcohol. EtG and EtS are very polar analytes, which make them difficult to chromatograph using reversed-phase chromatography. These analytes often elute early, which can lead to irreproducible results. When EtG and EtS are analyzed by LC/MS with a mobile phase that contains formic acid, the signal of these two analytes can be suppressed. This leads to increased LOQ and cutoffs. We examined the perfluorophenyl (PFP) stationary phase for its utility in analyzing EtG and EtS. This stationary phase has been shown to have greater retention of polar compounds than C18 reversed-phase columns. In addition, we compared the effect of formic acid to acetic acid on the separation. Methods Urine samples containing EtG and EtS were diluted 10:1, using 50mM acetic acid or 0.1% formic acid, into a 96-well microtiter filter plate containing a 0.2micron filter. Internal standards were added to the microtiter plate containing the urine samples. The samples were filtered through the filter plate and analyzed by LC/MS using the PFP column (50 x 2.7micron) with a 50mM acetic acid or 0.1% formic acid/acetonitrile mobile phase. The analytes were detected using negative mode ionization. The total analysis time was 4.5minutes. Results EtG and EtS showed improved retention using the PFP column. Retention times for EtG and EtS were 0.75 and 1.20 minutes respectively using the PFP column, compared to 0.4 and 0.3 minutes using the C18 column. The greater retention time improved the LOQ for both analytes.The LOQ for EtS and EtG were determined to be 125 and 250 ng/mL, respectively. Greater retention of EtG was observed by switching the modifier from formic acid to acetic acid. The retention time increased from 0.45 to 0.75 minutes. There was less signal suppression using acetic acid in place of formic acid. Improvement in peak shape was observed when the injection volume was reduced to 5microliters. The method was validated over a range of 250 to 10000 ng/mL for EtG and 125 to 5000 ng/mL for EtS. Acceptable linearity was obtained for both analytes. Accuracy was performed at three concentration levels. All three levels demonstrated acceptable accuracy with the difference between the measured and expected concentration being with in 20% of each other. Conclusions The PFP stationary can be used to test EtG and EtS. This stationary phase gave greater retention of EtS and EtG. The use of acetic acid improved the limit of detection by decreasing the ion suppression, which decreased the limit of detection. The assay was accurate and precise for both analytes, demonstrated in the validation.

Assessment of monitoring approaches to control Legionella pneumophila within a complex cooling tower system

Precise and rapid methods are needed to improve monitoring approaches of L. pneumophila (Lp) in cooling towers (CTs) to allow timely operational adjustments and prevent outbreaks. The performance of liquid culture (ASTM D8429-21) and an online qPCR device were first compared to conventional filter plate culture (ISO 11731-2017), qPCR and semi-automated qPCR at three spiked concentrations of Lp (serogroup 1) validated by flow cytometry (total/viable cell count). The most accurate was qPCR, followed by liquid culture, online and semi-automated qPCR, and lastly, by a significant margin, filter plate culture. An industrial CT system was monitored using liquid and direct plate culture by the facility, qPCR and online qPCR. Direct plate and liquid culture results agreed at regulatory sampling point, supporting the use of the faster liquid culture for monitoring culturable Lp. During initial operation, qPCR and online qPCR results were within one log of culture at the primary pump before deviating after first cleaning. Other points revealed high spatial variability of Lp. The secondary pumps and chiller had the most positivity and highest concentrations by both qPCR and liquid culture compared to the basin and infeed tank. Altogether, this suggests that results from monthly compliance sampling at a single location with plate culture are not representative of Lp risks in this CT due to the high temporal and spatial variability. The primary pump, rather than the CT basin, should be designated for sampling, as it is representative of the health risk. An annual multi point survey of the system should be conducted to identify and target Lp hot spots. Generally, a combination of liquid culture for compliance and frequent qPCR for process control provides a more agile and robust monitoring scheme than plate culture alone, enabling early treatment adjustments, due to lower limit of detection (LOD) and turnover time.

A Review of Artificial Waterfalls in Gardens

When artificial waterfalls are built in gardens, leaves from trees or vegetation often fall into the water storage pool and block the pipelines, requiring regular cleaning of pipelines. This not only increases the manpower needed for maintenance but also disrupts the use of the waterfalls. Therefore, it is necessary to design a new type of artificial waterfall that is suitable for gardens. The waterfall should incorporate features that make cleaning easier, including filter plates and water funnels to prevent clogging caused by fallen leaves and debris.

A label-free high-throughput protein solubility assay and its application to A[formula omitted]40

A major hallmark of Alzheimer's disease is the accumulation of aggregated amyloid β peptide (Aβ) in the brain. Here we develop a solubility assay for proteins and measure the solubility of Aβ40. In brief, the method utilizes 96-well filter plates to separate monomeric Aβ from aggregated Aβ, and the small species are quantified with the amine reactive dye o-phthalaldehyde (OPA). This procedure ensures that solubility is measured for unlabeled species, and makes the assay high-throughput and inexpensive. We demonstrate that the filter plates successfully separate fibrils from monomer, with negligible monomer adsorption, and that OPA can quantify Aβ peptides in a concentration range from 40 nM to 20 μM. We also show that adding a methionine residue to the N-terminus of Aβ1–40 decreases the solubility by <3-fold. The method will facilitate further solubility studies, and contribute to the understanding of the thermodynamics of amyloid fibril formation.

Red and green dual-wavelength Pr:LiGdF4 laser with a single birefringent filter

A simultaneous continuous-wave (CW) dual-wavelength Pr:LiGdF4 laser using a single birefringent filter (BF) plate under excitation with a frequency doubled optically pumped semiconductor laser (2 ω-OPSL) was experimentally demonstrated. We calculate the wavelength-dependent loss property of the BF. By adjusting the BF plate, the spectral intensity ratio of the generated wavelengths can be maintained to be 1:1. A simultaneous CW dual-wavelength Pr:LiGdF4 laser at 604 and 523 nm is experimentally realized. For a pump power of 7.2 W, red and green dual-wavelength laser radiation at 604 and 523 nm and 1.25 W of output power using a 4% output coupler could be generated. A slope efficiency of 19.8% with respect to the absorbed pump power and optical-to-optical efficiency of 17.4% for the highest-incident pump power were obtained. To our knowledge, this is the first study that has realized a dual-wavelength in Pr:LiGdF4 laser.

B-305 A Novel Dilute-n-shoot Method for Quantitating Isotonitazene and Desmetonitazene in Human Urine By LC/MS

Abstract Background Isonitazene is a benzimidazole derived opioid analgesic drug related to etonitazene, which has been sold as a designer drug. According to doctors isotonitazene has the potency of 20–200 times of fentanyl. The side effects of isotonitazene are like fentanyl and has been linked to many fatalities in Europe and the US. It has led to a number of overdoses through secondhand contact, by smelling or coming in contact with skin. It is slowly replacing fentanyl as the deadliest street drug in the US. We developed a dilute-n-shoot method that would test for isotonitazene and its metabolite metodesnitazene in human urine. This method used filtration to remove unwanted particulates and protein. It reduces the number of steps needed to prepare samples for liquid chromatography/mass spectrometry analysis compared to methods that require centrifugation. This assay allows for easier training of staff. In addition, it is easily adaptable to increase sample load. Method Isotonitazene and metodesnitazene urine samples were prepared for LC/MS analysis by diluting them 1:20 in 0.1% formic acid in water. These samples were spiked with internal standard and filtered through a 0.2 μm Captiva 96-well filter plate. Isotonitazene and metodesnitazene concentrations were measured using LC/MS in the positive ion mode. The separation was obtained using a phenylhexyl UPLC column, 50 × 2.1 mm, 1.8 μm, along with a 50:50 acetonitrile/methanol/water formic acid gradient mobile phase. Results The separation was completed in a proximately 4.5 min with good resolution between isotonitazene and metodesnitazene. Validation studies demonstrated that this method was linear from 2 to 100 ng/mL, with r2 ≥ 0.990 for both isotonitazene and metodesnitazene. Interday and intraday precision for both analytes were acceptable, with CV values &amp;lt; 5.0%. Accuracy measurements at 5, 25 and 80 ng/mL gave results where the percent difference was ≤20% for the 4 ng/mL concentration and ≤15% for the 25 and 80 ng/mL. A study of interfering compounds showed that there were no interferences that would affect the accuracy of isotonitazene and metodesnitazene. Recovery studies showed that &amp;gt; 90% of each analyte was recovered from the filtration step. The LOQ was determined to be 2 ng/mL and the LOD was determined to be 0.5 ng/mL. The reportable range was determined to be 2 to 200 ng/mL. The results of this validation will be discussed in detail in this poster. Conclusion The method was linear and precise for both analytes over a range of 2 to 100 ng/mL. The method was reproducible and easy to use. Isotonitazene and metodesnitazene could easily be quantitated in human urine using this method.

B-205 A Simple Method for Opioids, Synthetic Opioids and PCP Detection in Hair Samples by LC-MS/MS

Abstract Background Hair analysis is useful for monitoring exposure to drugs and is a unique body material for the retrospective detection of drug consumption due to its large detection window, and it is easy to collect, store, and transport. Establishing a LC-MS/MS protocol for opioids determination may be challenging due to similarities among the molecular structures and the MS/MS fragmentation profile. This study aimed to develop and validate a simple, rapid, and sensitive LC-MS/MS method for quantification of 6-acetylcodeine, 6-acetylmorphine, codeine, dihydrocodeine, EDDP, PCP, fentanyl, heroin, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone, oxymorphone and tramadol in hair samples. Methods In this method, 15 mg of hair in a 2.0 mL microtube was decontaminated sequentially with dichloromethane and methanol. The sample was dried, and 0.75 mL of extraction solvent and a labeled internal standards solution were added. The hair sample was pulverized in a FastPrep-24™ 5G from MP-Biomedicals and then sonicated at 60°C for 60 min. The sample was centrifuged and filtered with Captiva filtration plates. Then, 100 µL of supernatant was added to 100 uL of ultrapure water and 5.0 uL was injected directly into the LC-MS/MS system. Chromatographic separation was performed on an Agilent 1290 Infinity II equipped with HALO Biphenyl column, and employing a mobile phase constituted by acetonitrile with 0.1% of formic acid and 5 mM of ammonium formate. The detection was performed with a Sciex 6500+ QTrap mass spectrometer. Results The current method was successfully validated for carryover, linearity, precision, recovery, limits of detection and quantification, and the measurement of uncertainty was calculated. The results were summarized in the Table 1. Conclusion The developed LC-MS/MS method was simple, rapid, and sensitive to detect opioids in hair samples.

Comparison of Miniaturized Chromatographic Columns and 96-Well Plates for Automated Antibody Purification under Economic and Sustainable Aspects

Therapeutic antibodies are an area of major interest in treating infectious diseases, autoimmune diseases, and cancer. Efficient purification strategies are required to discover and produce antibodies, representing a significant cost driver. Miniaturization and automation of the chromatographic purification process may contribute to cost reduction. In this article, miniaturized chromatographic columns and 96-well filter plates are used to purify an IgG antibody from cell cultures and are compared in terms of quality, cost, and sustainability. The validation results of the two miniaturized chromatographic antibody purification methods indicate high efficacy and are comparable except for minor differences in yield. The lowest cost per sample can be obtained with the miniaturized chromatographic columns, as annual throughput can be maximized with the miniaturized plates. By evaluating sustainability, significant reductions in laboratory waste produced during antibody purification can be shown, along with an increase in employee safety by using the automation system. Overall, the comparison of results shows that, in the development of new purification strategies, the type of implementation has a decisive influence on the outcomes in terms of recovery, cost-effectiveness, and sustainability.

Determination of metarrestin (ML-246) in human plasma for a first-in-human clinical pharmacokinetic application by a simple and efficient uHPLC-MS/MS assay

Metarrestin is a first-in-class small molecule inhibitor targeting the perinucleolar compartment, a subnuclear body associated with metastatic capacity. Promising preclinical results led to the clinical translation of the compound into a first-in-human phase I trial (NCT04222413). To characterize metarrestin’s pharmacokinetic profile in humans, a uHPLC-MS/MS assay was developed and validated to determine the disposition of the drug in human plasma. Efficient sample preparation was accomplished through one-step protein precipitation paired with elution through a phospholipid filtration plate. Chromatographic separation was achieved with gradient elution through an Acuity UPLC® BEH C18 column (50 × 2.1 mm, 1.7 µm). Tandem mass spectrometry facilitated the detection of metarrestin and tolbutamide, the internal standard. The effective calibration range spanned 1–5000 ng/mL and was both accurate (range −5.9 % to 4.9 % deviation) and precise (≤9.0 %CV). Metarrestin proved stable (≤4.9 % degradation) under various assay-imposed conditions. Matrix effects, extraction efficiency, and process efficiency were assessed. Further, the assay was successfully able to determine the disposition of orally administered metarrestin in patients from the lowest dose cohort (1 mg) for 48 h post-administration. Thus, the validated analytical method detailed in this work is simple, sensitive, and clinically applicable.

A Preliminary Anti-Glare System for Traffic Vehicles Using Polarizing Filters and a Polarizing Flip Plate

In the past, polarizing filters were attached to cars’ halogen headlights to reduce glare for other vehicles. However, the filters absorbed a significant amount of light and made it difficult for drivers to see properly. Coupled with overheating issues and numerous technical and logistical limitations, polarized automotive lighting systems have not become widespread. In this research, we propose using a polarized LED lighting system to improve drivers’ visibility. Our results demonstrated an illuminance reduction of up to 97.5% when simultaneously using a polarized headlight filter and flip plate. Additionally, our system’s lower operating temperatures resulted in a lifespan increase of approximately 120 times compared to a conventional halogen lighting system.

Passenger vehicle interior decontamination by low concentration hydrogen peroxide vapor following a wide area biological contamination incident.

To assess low concentration hydrogen peroxide (LCHP) (H2O2) vapor dispersed with a home humidifier for its ability to decontaminate vehicle interiors contaminated with Bacillus anthracis surrogate Bacillus atrophaeus spores. Efficacy of a vaporized 3% H2O2 solution was evaluated for liquid volumes, on/off vehicle heating, ventilation, and air conditioning (HVAC) system operations, and temperatures that ranged from 5 to 27°C. Survival of the spores was assessed by quantification of remaining viable spores with efficacy quantified in terms of mean log10 reduction. Decontamination efficacy after the 6-day dwell time increased when the 3% H2O2 liquid volume was doubled, increasing from 4-of-10 to 10-of-10 nondetects (zero colonies counted using standard dilution and filter plating) inside the vehicle cabin. Recirculating cabin air through the HVAC system during decontamination decreased efficacy to 6-of-10 non-detects. While no 6-log10 reduction in viable spores was observed on the cabin filter with the cabin filter kept in place, a 6-log10 reduction was achieved after its removal and placement in the cabin during treatment. Results from this study allow for informed decisions on the use of LCHP vapor as an effective decontamination approach for vehicle interiors.

Assessment of the Synergetic Performance of Nanostructured CeO2-SnO2/Al2O3 Mixed Oxides on Automobile Exhaust Control.

In order to control diesel exhaust emission, CeO2-SnO2/Al2O3 (CTA) mixed oxides were prepared and coated on perforated stainless steel (SS) filter plates, and the catalytic activities were analyzed in this work. The CeO2-SnO2 (different compositions of Ce/Sn-2:8; 1:1; 8:2) composites and Al2O3 were prepared separately via a co-precipitation approach, and CeO2-SnO2/Al2O3 (CTA) mixed oxides were attained by mechanical mixing of 75 wt% CeO2-SnO2 composites with 25 wt% Al2O3. X-ray diffraction (XRD) and Raman spectroscopy were performed for all three CeO2-SnO2/Al2O3 (CTA) mixed oxides; the CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample confirmed the presence of cubic and tetragonal mixed faces, which enhances the redox nature (catalytic activities). Various characterizations such as high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), and a scanning electron microscope (SEM) were employed on CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample to investigate the structural, textural, compositional, and morphological properties. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample was coated on a perforated stainless steel (SS) filter plate via a simple, cost-effective, and novel method, and an exhaust emission test for various compression ratios (CR), injection pressure (IP), and load (L) was completed using an AVL Digas analyzer. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample, with a size of 10.22 nm and a high surface area of about 73 m2 g-1, exhibit appreciable catalytic properties.

ODP179 Development of Derivatization-free ID-LC/MS/MS Method for Simultaneous Measurement of Human Serum Monosaccharides

Abstract According to the CDC's National Diabetes Statistics Report for 2020, it is estimated that 34.2 million, 10.5% of the U. S. population, have diabetes. High fructose intake has also been associated with increased de novo lipogenesis in the liver leading to non-alcoholic fatty liver disease (NAFLD). Emerging evidence suggests that measuring fructose, galactose, and other saccharides in addition to glucose may be helpful for diagnosis of metabolic disorders and other diseases. Therefore, there is a need for an accurate and precise laboratory method for measuring serum monosaccharide panels. Traditional monosaccharide assays used in patient care often can only quantitate one monosaccharide at a time. We aim to develop a high-throughput analytical method for simultaneous measurement of serum monosaccharides that is suitable for large scale epidemiologic studies. Our assay is based on a derivatization-free ID-LC/MS/MS procedure. Certified primary reference materials of monosaccharides from NIST (Gaithersburg, MD) were used for assay calibration. The serum samples were spiked with 13 C labeled internal standards. The monosaccharides were isolated from serum matrix by acetonitrile protein precipitation and filtration in 96-well filter plate (0.2um, porous PTFE). Aliquot of the acetonitrile filtrate was applied on an AB SCIEX Triple Quad™ 6500 LC/MS/MS system for analysis. The monosaccharides including glucose, galactose, fructose, mannose, and potential interferences were resolved from each other on Unison UK Amino column (3×250mm) eluted with acetonitrile and water gradient. Selective reaction monitoring in negative electrospray ionization mode was used for quantitation of monosaccharides in the samples. The measurement ranges covered 10–402 mg/dL for glucose, which is sufficient to monitor the serum glucose levels in normal, hypo-, and hyperglycemia patient samples. Using 4 levels of NIST SRM 965b (values assigned using GC-MS based reference measurement procedure), the method demonstrated excellent measurement accuracy of over 98% for serum glucose. The imprecision of serum glucose measurement was within 3%. Imprecision and accuracy of lower abundant serum monosaccharides were lower than 6% and above 96%, respectively. The application of 96-well format filter plate and automated liquid handler system significantly improves the throughput of sample preparation. The current analytical method can be used to simultaneously measure the concentrations levels of a panel of serum monosaccharides with appropriate accuracy and precision. Free of derivatization, simple sample procedure and application of automation system significantly improves throughput of the assay which are suitable for routine serum monosaccharides assay in clinical laboratories and for large biomonitoring studies. Presentation: No date and time listed

P455 Identification of Cryptic species of Aspergillus using Beta-tubulin gene in a tertiary care center in South India

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM ObjectivesTo identify cryptic species of the genus Aspergillus using Beta-tubulin gene by sequence typing.Methods Aspergillus grown from various clinical samples (Ear swab, Bronchial wash, Endotracheal Aspiration, Paranasal sinus, BAL, Sputum) was subcultured on Sabouraud's Dextrose Agar/Oatmeal Agar.Tease mount/Slide culture was done to study the morphological features of the hyphae, size, shape, and arrangement of the conidia.DNA Extraction using phenol-chloroform method: DNA was extracted and purified directly from 4-day-old culture and used as a template for polymerase chain reaction (PCR) amplification.DNA Amplification: A fragment of the target gene were amplified using PCR.The primer pairs used for Beta-tubulin gene was Bt2a (Forward primer) and Bt2b (Reverse primer).Beta-tubulin.Bt2a FGGTAACCAAATCGGTGCTGCTTTCBt2b RACCCTCAGTGTAGTGACCCTTGGCDNA Purification: The PCR product was purified with multi-screen filter plates.Gel electrophoresis: The amplified DNA product was subjected to agarose gel electrophoresis and specific band formation was to be observed for the species of Aspergillus.DNA Sequencing: The purified product will be used as a template for sequencing. An applied biosystem 3730 sequencer will be used to obtain DNA sequences.Phylogenetic Analysis: Parsimony analysis of individual and combined matrices will be conducted using PAUP version 4.0b10 software/free software at phylogeny.fr by the maximum parsimony (MP) and Neighbor-joining methods.The results will be represented using a dendrogram.ResultsA total of 30 Aspergillus isolates were collected and identified using Phenotypic methods.The DNA extraction and PCR amplification were done and sent for Sequencing. The results of Sequence typing are awaited.ConclusionCryptic species are morphologically indistinguishable forms of Aspergillus and their identifications can be confirmed exclusively by using molecular techniques which have led to the description of previously unknown or rare species among different Aspergillus species complex. According to studies, the frequency of such species was found to be 10% in TRANSNET study U.S and 12% in FILPOP study Spain. Most of these species are less susceptible and certain species are multidrug-resistant (azoles and amphotericin B) and the emergence of antifungal-resistance among the Aspergillus species forms the importance in identifying Cryptic species.

Kapok fiber-supported liquid extraction for convenient oil samples preparations: A feasibility and proof-of-concept study

In this study, a novel kapok fiber-supported liquid extraction (KF-SLE) method was developed for conveniently extracting analytes from oil samples. Natural kapok fiber without any pretreatment was directly used as an oil support medium. The extraction device was conveniently constructed by directly packing some kapok fibers into a syringe tube. Due to the fibrous property of the kapok fiber, no filter plate was needed. The cost of a KF-SLE device was as low as 0.5 CNY. The KF-SLE process was conveniently conducted using a simple three-step protocol: (1) the oil sample without any pretreatment including dilution was added directedly; (2) then, the oil-immiscible extractant was added; (3) after waiting a certain time for static extraction, the extractant was eluted out by pressing the kapok fibers with the syringe plunger. The extractant could be directly transferred for subsequent instrumental detection. For the feasibility and proof-of-concept study, the method was applied to quantify four synthetic flavor chemicals in edible oils. Satisfied quantification results were obtained with the correlation coefficient (R2) being greater than 0.996, the relative recoveries ranging from 92.90% to 107.53% and intra- and inter-day RSDs being less than 7.56%. All in all, for the first time, the SLE technique was expanded to process oil samples and the method has the characteristics of low cost, environmental friendliness, high sample processing throughput and ease of automation, offering a promising approach for edible oil sample preparations.

Elimination of Microplastics at Different Stages in Wastewater Treatment Plants

Microplastic pollution has been widely studied as a global issue due to increased plastic usage and its effect on human and aquatic life. Microplastics originate from domestic and industrial activities. Wastewater treatment plants (WWTPs) play an important role in removing a significant amount of microplastics; otherwise, they end up in bioaccumulation. This study provides knowledge about the characteristics of microplastics, removal efficiency, and the correlation between wastewater quality and microplastic concentrations from three different WWTPs that differ in the type of biological and advanced wastewater treatment techniques that are believed to play an important role in microplastic removal. Microplastics of different types, such as fragments, fibers, and beads, are identified by using an optical microscope before and after the treatment process at each stage to assess the effect of different treatment techniques. In the screening unit and primary clarifier unit, WWTP-B shows the highest removal efficiency with 74.76% due to a distribution flow system installed before the primary clarifier to ensure a constant flow of wastewater. WWTP-B uses a bioreactor consisting of a filter plate coated with activated carbon (BSTS II) that can enhance the adaptability and adhesion of microorganisms and showed that 91.04% of the microplastic was removed. Furthermore, only WWTP-A and WWTP-B were applied coagulation, followed by the disc filter; they showed significant results in microplastic removal, compared to WWTP-C, which only used a disc filter. In conclusion, from all WWTP, WWTP-B shows good treatment series for removing microplastic in wastewater; however, WWTP-B showed a high rate of microplastic removal; unfortunately, large amounts of microplastics are still released into rivers.

Permeability of Olmesartan Medoxomil from Lipid Based and Suspension Formulations using an Optimized HDM-PAMPA Model

Hexadecane membrane-parallel artificial membrane permeability assay (HDM-PAMPA) is based on an artificial hexadecane membrane that separates the two compartments (donor and acceptor compartment). This model is used to predict the permeability of drugs in gastrointestinal tract and to simulate the passive absorption. In vivo behaviour of the drugs can be estimated with these systems in drug development studies. In our study we optimized HDM-PAMPA model to determine permeability of olmesartan medoxomil (OM) lipid based drug delivery system (OM-LBDDS). In order to prove that LBDDS formulation facilitates the weak permeability of OM, permeation rates were compared with the OM suspension formula (containing 0.25% v/w CMC). The experiment was performed on a 96-well MultiScreen® PAMPA filter plate (MAIPN4510). The permeability of olmesartan formulations from the donor to acceptor compartment separated by a HDM membrane were determined by the previous validated HPLC method. We created positive control series without coating hexadecane membrane to present the LBDDS and suspension formulation permeability from uncoated plates. The effective permeability constant (Pe) was calculated by the formula and improvement of permeability of OM-LBDDS formulation from hexadecane membrane was confirmed. On the contrary there was no permeation of OM-Suspension in the hexadecane coated plates. As a result, the intestinal permeability of OM-LBDDS was calculated to be at least 100 times more than the suspension. OM-Suspension permeation was only observed in the hexadecane uncoated positive control plates. This was also manifestation of HDM-PAMPA mimicking permeability of intestines because of its lipidic construction.

A new species of early Cambrian arthropod reconstructed from exceptionally preserved mandibles and associated small carbonaceous fossils (SCFs)

AbstractMandibulate arthropods (myriapods, hexapods and crustaceans) account for a major component of extant animal diversity but their origins remain unclear. Here, we re‐examine the record of exceptionally preserved arthropodan microfossils, including mandibles, from the lower Cambrian (Stage 4) Mount Clark Formation, Northwest Territories, Canada. The assemblage comes from a single drillcore horizon and occurs as thousands of small carbonaceous fossils (SCFs) representing disarticulated body parts. The mandibles occur as isolated molar surfaces with an elongate outline, a heavy setal fringe, and a subtle right–left asymmetry. These are sufficiently distinctive to diagnose a new genus and species of arthropod, Masticaris fimbriata. Co‐occurring SCFs include diverse appendage lobes and ventral body fragments, along with spines and setae assignable to 53 morphological categories and occurring either singly or in arrays, including filter plates. Most are plausibly interpreted as belonging to the feeding apparatus of M. fimbriata. The mandibles and filter plates correspond to those in extant pancrustaceans, particularly branchiopods, although the mouthparts of some more basal Cambrian arthropods raise the possibility of convergent feeding adaptations. Overall, anatomical and taphonomic continuity with younger SCFs suggests that M. fimbriata belongs to an early pancrustacean radiation that is still largely cryptic in the fossil record. More generally, the assemblage provides an inventory of fine‐scale cuticular specializations in early Cambrian arthropods that prefigure the trophic versatility and ecological dominance of crustaceans in the modern marine fauna.

Experimental Study on the Dust-Cleaning Performance of New Structure Microporous Membrane Filter Plate

On the basis of the existing dust collector structure, this study designed a fan-shaped new structure microporous membrane filter plate (NSMMFP). The pressure distribution law of the NSMMFP can be obtained by measuring the wall surface peak pressure under different injection pressures. The powder attachment experiment was carried out to explore the influence of the dust moisture content on the dust stripping rate (DSR), and a high-speed camera was used to observe the peeling process of the dust. The results show that the peak pressure of each measuring point and the average wall surface peak pressure gradually increase with the injection pressure. The dust stripping quality (DSQ) and rate show an increasing trend as a whole as the injection distance. The DSR of the filter plate shows a downward trend when the dust quality G increases, while DSQ shows the opposite trend. Furthermore, as the dust moisture content increases, the DSQ and DSR gradually decrease. As the dust moisture content increases, the dust attached to the surface of the filter plate is more fragmented and peels from the surface of the filter plate during the dust cleaning process.

Developing a regeneration process for ceramic elements of vacuum filters in operation at the copper concentrate filtration station of Copper Plant

Copper concentrate filtration station constitutes an initial stage in the production circuit of the Copper Plant, and maintaining the required throughput is crucial. Concentrate slurries from Talnakh and Norilsk Concentrators go to the filtration station, where industrial slurry products are also introduced in the production cycle. The filtration station is responsible for two key processes &ndash; thickening and filtering. Incoming slurry goes through two consecutive stages of thickening and the thickened product is then filtered. Due to increased performance targets, ceramic filters experience higher loads. Because of it, the established wash modes fail to maintain the necessary permeability of the filter membranes. Brown deposit can be regularly found on the ceramic filtering elements that significantly affects their permeability leading to emergency change-outs. In the course of the study, researchers found what causes the brown deposit on the surface of filter plates and how it forms. A study was conducted that looked at the applicability of reagents for the regeneration of filtering elements. Application of sulphuric acid was found to be the optimum solution. Further studies helped determine the concentration of sulphuric acid solution necessary to remove the deposit. Thus, it is proposed to use decopperized electrolyte from the copper electrowinning plant for filter plate regeneration. The best technical solution was also found. Thus, it is reasonable to use a separate wash tank to take a filter apart before removing the deposit. The industrial tests conducted demonstrated that the regeneration efficiency of the proposed process can be as high as 97%.Other contributors to this research include A. V. Egorov, V. V. Velichko and O. Yu. Kokoev.