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1.
Anal Bioanal Chem ; 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38896239

ABSTRACT

Residues of various highly polar pesticides and their metabolites are commonly found in numerous food products. Some of these compounds, such as glyphosate, are not only used in large amounts in agriculture, but are also controversially discussed in public. Here, we present a method, employing ion chromatography (IC) coupled to tandem mass spectrometry (IC-MS/MS), for the analyses of glyphosate, aminomethyl phosphonic acid (AMPA), N-acetyl-glyphosate (NAGly), fosetyl, and 10 further highly polar pesticides and metabolites in various plant and animal matrices following a minimal sample preparation by means of the QuPPe method. Thorough investigations showed that an AS19 column enabled the analysis of all 14 compounds within 30 min. The best sensitivity could be obtained with the make-up solvent acetonitrile being admixed to the mobile phase at a 1:2 flow rate ratio. Matrix effects were thoroughly studied in terms of ion suppression and retention time shifts. Conductivity detection was used to monitor elution profiles of matrix co-extractives in comparison with matrix effect profiles obtained by continuous post-column infusion of a mix with 13 highly polar pesticides and metabolites. These tests indicated that a fivefold dilution of QuPPe extracts was suitable for the routine analysis of samples for MRL-conformity, as it considerably reduced matrix effects maintaining sufficient sensitivity and high recovery rates in eight different commodities. The suitability of the final method for its application in routine analysis was verified by the analysis of >130 samples containing incurred residues where the results were compared with two existing LC-MS/MS methods.

2.
Se Pu ; 42(6): 508-523, 2024 Jun.
Article in Chinese | MEDLINE | ID: mdl-38845512

ABSTRACT

Given continuous improvements in industrial production and living standards, the analysis and detection of complex biological sample systems has become increasingly important. Common complex biological samples include blood, serum, saliva, and urine. At present, the main methods used to separate and recognize target analytes in complex biological systems are electrophoresis, spectroscopy, and chromatography. However, because biological samples consist of complex components, they suffer from the matrix effect, which seriously affects the accuracy, sensitivity, and reliability of the selected separation analysis technique. In addition to the matrix effect, the detection of trace components is challenging because the content of the analyte in the sample is usually very low. Moreover, reasonable strategies for sample enrichment and signal amplification for easy analysis are lacking. In response to the various issues described above, researchers have focused their attention on immuno-affinity technology with the aim of achieving efficient sample separation based on the specific recognition effect between antigens and antibodies. Following a long period of development, this technology is now widely used in fields such as disease diagnosis, bioimaging, food testing, and recombinant protein purification. Common immuno-affinity technologies include solid-phase extraction (SPE) magnetic beads, affinity chromatography columns, and enzyme linked immunosorbent assay (ELISA) kits. Immuno-affinity techniques can successfully reduce or eliminate the matrix effect; however, their applications are limited by a number of disadvantages, such as high costs, tedious fabrication procedures, harsh operating conditions, and ligand leakage. Thus, developing an effective and reliable method that can address the matrix effect remains a challenging endeavor. Similar to the interactions between antigens and antibodies as well as enzymes and substrates, biomimetic molecularly imprinted polymers (MIPs) exhibit high specificity and affinity. Furthermore, compared with many other biomacromolecules such as antigens and aptamers, MIPs demonstrate higher stability, lower cost, and easier fabrication strategies, all of which are advantageous to their application. Therefore, molecular imprinting technology (MIT) is frequently used in SPE, chromatographic separation, and many other fields. With the development of MIT, researchers have engineered different types of imprinting strategies that can specifically extract the target analyte in complex biological samples while simultaneously avoiding the matrix effect. Some traditional separation technologies based on MIP technology have also been studied in depth; the most common of these technologies include stationary phases used for chromatography and adsorbents for SPE. Analytical methods that combine MIT with highly sensitive detection technologies have received wide interest in fields such as disease diagnosis and bioimaging. In this review, we highlight the new MIP strategies developed in recent years, and describe the applications of MIT-based separation analysis methods in fields including chromatographic separation, SPE, diagnosis, bioimaging, and proteomics. The drawbacks of these techniques as well as their future development prospects are also discussed.


Subject(s)
Molecular Imprinting , Humans , Chromatography, Affinity/methods , Solid Phase Extraction/methods , Enzyme-Linked Immunosorbent Assay
3.
Food Res Int ; 190: 114604, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38945616

ABSTRACT

Sheep's milk (SM) is known to differ from cow's milk (CM) in nutritional composition and physicochemical properties, which may lead to different digestion behaviours. This work aimed to investigate the impact of the species (cow vs sheep) and the structure (milk vs yogurt) on the digestion of dairy products. Using an in vitro static gastrointestinal digestion model, CM, SM, cow's milk yogurt (CY) and sheep's milk yogurt (SY) were compared on particle size evolution, microscopic observations, degree of lipolysis, degree of proteolysis, specific protein degradation and calcium bioaccessibility. Species and structure affected particle size evolution during the gastric phase resulting in smaller particles for yogurts compared to milks as well as for CM products compared to SM products. Species impacted lipid composition and lipolysis, with SM products presenting higher short/medium-chain fatty acids content and higher intestinal degree of lipolysis. Proteolysis was influenced by structure, with milks showing higher intestinal degree of proteolysis compared to yogurts. Caseins were digested faster in CM, ⍺-lactalbumin was digested faster in SM despite its higher concentration, and during gastric digestion ß-lactoglobulin was more degraded in CM products compared to SM products and more in yogurts compared to milks. Lastly, SM products released more bioaccessible calcium than CM products. In conclusion, species (cow vs sheep) impacted more the digestion compared to the structure (milk vs yogurt). In fact, SM was different from CM mainly due to a denser protein network that might slow down the accessibility of the enzyme to its substrate which induce a delay of gastric disaggregation and thus lead to slower the digestion of the nutrients.


Subject(s)
Digestion , Lipolysis , Milk , Particle Size , Proteolysis , Yogurt , Animals , Digestion/physiology , Cattle , Yogurt/analysis , Sheep , Milk/chemistry , Lactoglobulins/metabolism , Gastrointestinal Tract/metabolism , Dairy Products/analysis , Lactalbumin/metabolism , Caseins/metabolism , Caseins/analysis , Species Specificity , Milk Proteins/analysis , Milk Proteins/metabolism
4.
Food Res Int ; 188: 114510, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38823887

ABSTRACT

The aim of this study was to explore the copigmentation effect of gallic acid on red wine color and to dissect its mechanism at the molecular level. Three-dimensional studies, e.g., in model wine, in real wine and in silico, and multiple indicators, e.g., color, spectrum, thermodynamics and phenolic dynamics, were employed. The results showed that gallic acid significantly enhanced the color quality and stability of red wine. Physico-chemical interactions and chemical transformations should be the most likely mechanism, and physico-chemical interactions are also a prerequisite for chemical transformations. QM calculations of the physico-chemical interactions proved that the binding between gallic acid and malvidin-3-O-glucoside is a spontaneous exothermic reaction driven by hydrogen bonding and dispersion forces. The sugar moiety of malvidin-3-O-glucoside and the phenolic hydroxyl groups of gallic acid affect the formation of hydrogen bonds, while the dispersion interaction was related to the stacking of the molecular skeleton.


Subject(s)
Anthocyanins , Color , Gallic Acid , Glucosides , Hydrogen Bonding , Thermodynamics , Wine , Gallic Acid/chemistry , Wine/analysis , Glucosides/chemistry , Anthocyanins/chemistry , Quantum Theory , Phenols/chemistry
5.
J Pestic Sci ; 49(2): 65-76, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38882703

ABSTRACT

The matrix effects (ME) in simultaneous analysis of pesticide residue using liquid chromatography-tandem mass spectrometry (LC-MS/MS) were evaluated by comparing the slopes of matrix-matched and reagent-only calibrations of four types of vegetable samples. Both the sampling and measurement variances of the ME were also determined using one-way analysis of variance. Substantial ion suppression (ME<-20%) was observed in komatsuna, spinach, and tomato when a modified Japanese official method was implemented. The ME magnitude varied significantly due to sample variability for some pesticides, but it varied by no more than 4% as a result of analytical procedure variance. This study also showed that the addition of stable isotope-labeled internal standards at low concentrations improved the recovery of pesticides from samples at various residue levels. The findings of this study highlight the importance and practical application of internal standards and the matrix-matched calibration method in residue analysis using LC-MS/MS.

7.
Water Res ; 257: 121685, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38728774

ABSTRACT

Water disinfection is undoubtedly regarded as a critical step in ensuring the water safety for human consumption, and ozone is widely used as a highly effective disinfectant for the control of pathogenic microorganisms in water. Although the diminished ozone efficiencies in complex water matrices have been widely reported, the specific extent to which individual components of matrix act on the virus inactivation by ozone remains unclear, and effective methodologies to predict the comprehensive effects of various factors are needed. In this study, the decoupled impact of the intricate water matrix on the ozone inactivation of viruses was systematically investigated and assessed from a simulative perspective. The concept of "equivalent ozone depletion rate constant" (k') was introduced to quantify the influence of different species, and a kinetic model was developed based on the k' values for simulating the ozone inactivation processes in complex matrix. The mechanisms through which diverse species influenced the ozone inactivation effectiveness were identified: 1) competition effects (k' = 105∼107 M-1s-1), including organic matters and reductive ions (SO32-, NO2-, and I-), which were the most influential species inhibiting the virus inactivation; 2) shielding effects (k' = 103∼104 M-1s-1), including Ca2+, Mg2+, and kaolin; 3) insignificant effects (k' = 0∼1 M-1s-1), including Cl-, SO42-, NO3-, NH4+, and Br-; 4) promotion effects (k' = ∼-103 M-1s-1), including CO32- and HCO3-. Prediction of ozone disinfection efficiency and evaluation of species contribution under complex aquatic matrices were successfully realized utilizing the model. The systematic understanding and methodologies developed in this research provide a reliable framework for predicting ozone inactivation efficiency under complex matrix, and a potential tool for accurate disinfectant dosage determination and interfering factors control in actual wastewater treatment processes.


Subject(s)
Disinfection , Ozone , Virus Inactivation , Wastewater , Ozone/pharmacology , Wastewater/virology , Virus Inactivation/drug effects , Disinfection/methods , Water Purification , Disinfectants/pharmacology , Models, Theoretical , Kinetics
8.
Materials (Basel) ; 17(10)2024 May 11.
Article in English | MEDLINE | ID: mdl-38793348

ABSTRACT

Harmful substances in consumer goods pose serious hazards to human health and the environment. However, due to the vast variety of consumer goods and the complexity of their substrates, it is difficult to simultaneously detect multiple harmful substances in different materials. This paper presents a method for the simultaneous determination of 41 harmful substances comprising 17 phthalates (PAEs), 8 organophosphate flame retardants (OPFRs), and 16 polycyclic aromatic hydrocarbons (PAHs) in five types of products using the matrix-matching calibration strategy. The method employs an efficient ultrasonic extraction procedure using a mixture of dichloromethane and methylbenzene, followed by dissolution-precipitation and analysis through gas chromatography-mass spectrometry. Compared with previous experiments, we established a universal pretreatment method suitable for multi-matrix materials to simultaneously determine multiple harmful substances. To evaluate the effects of the matrix on the experimental results, we compared neat standard solutions and matrix-matching standard solutions. The results demonstrated that all compounds were successfully separated within 30 min with excellent separation efficiency. Additionally, the linear relationships of all analytes showed strong correlation coefficients (R2) of at least 0.995, ranging from 0.02 mg/L to 20 mg/L. The average recoveries of the target compounds (spiked at three concentration levels) were between 73.6 and 124.1%, with a relative standard deviation (n = 6) varying from 1.2% to 9.9%. Finally, we tested 40 different materials from consumer products and detected 16 harmful substances in 31 samples. Overall, this method is simple and accurate, and it can be used to simultaneously determine multiple types of hazardous substances in multi-matrix materials by minimizing matrix effects, making it an invaluable tool for ensuring product safety and protecting public health.

9.
Environ Pollut ; 355: 124180, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38768676

ABSTRACT

Solid phase extraction (SPE) has been widely used for pretreatment in target screening (TS) analysis. However, some compounds are difficult to recover by SPE or their recovery is unstable for environmental samples. In this study, we tested large-volume injection (LVI) without SPE for TS analysis of 103 compounds listed by the Ministry of the Environment (Japan)-so-called 'items to be surveyed'-using liquid chromatography high-resolution mass spectrometry. We evaluated the limit of quantification (LOQ) by LVI and compared this LOQ with the LOQ by SPE pretreatment using a hydrophilic-lipophilic balance (HLB) combined with activated carbon, which was found previously to afford the best SPE cartridges for target compounds recovery. The LOQ generally decreased as the injection volume increased, and the LOQ was at least 250 times lower for a 500-µL injection than for a 2-µL injection for half of the compounds. LVI provided LOQs lower than the predicted no effect concentration for more compounds than the SPE method. The average matrix effect (ME) by LVI was in the range 70%-130% for 69 out of 97 compounds. The ME was higher or lower for some of the remaining compounds, but the ME was in the range 10%-1000% for all 18 water samples for 84 of the 97 compounds. Comparing the ME by LVI and the recovery ratio by the SPE method showed that LVI achieved more accurate quantitation than the SPE method for a larger number of compounds. Therefore, LVI provides better sensitivity and quantitativeness than the SPE method using HLB and activated carbon for TS analysis of as many 'items to be surveyed' as possible.


Subject(s)
Environmental Monitoring , Mass Spectrometry , Solid Phase Extraction , Water Pollutants, Chemical , Water Pollutants, Chemical/analysis , Solid Phase Extraction/methods , Environmental Monitoring/methods , Chromatography, Liquid/methods , Mass Spectrometry/methods , Japan
11.
Nutrients ; 16(7)2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38612977

ABSTRACT

When food products are often considered only as a source of individual nutrients or a collection of nutrients, this overlooks the importance of interactions between nutrients, but also interactions between nutrients and other constituents of food, i.e., the product matrix. This product matrix, which can be defined as 'The components of the product, their interactions, their structural organization within the product and the resultant physicochemical properties of the product', plays a critical role in determining important product properties, such as product stability, sensory properties and nutritional and health outcomes. Such matrix effects can be defined as 'the functional outcome of specific component(s) as part of a specific product matrix'. In this article, dairy matrix effects are reviewed, with particular emphasis on the nutrition and health impact of dairy products. Such matrix effects are critical in explaining many effects of milk and dairy products on human nutrition and health that cannot be explained solely based on nutrient composition. Examples hereof include the low glycemic responses of milk and dairy products, the positive impact on dental health, the controlled amino acid absorption and the absence of CVD risk despite the presence of saturated fatty acids. Particularly, the changes occurring in the stomach, including, e.g., coagulation of casein micelles and creaming of aggregated fat globules, play a critical role in determining the kinetics of nutrient release and absorption.


Subject(s)
Milk , Nutrients , Humans , Animals , Nutritional Status , Amino Acids , Blood Coagulation
12.
Diagnostics (Basel) ; 14(8)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38667445

ABSTRACT

Glucose meters provide a rapid blood glucose status for evidence-based diagnosis, monitoring, and treatment of diabetes mellitus. We aimed to evaluate the commutability of processed blood materials (PBMs) and their use in the performance evaluation of glucose meters. Two PBMs obtained by the fixed-cell method were analyzed for homogeneity, stability, and commutability. The compatibility of ten pairs between mass spectrometry and each glucose meter was categorized as compatible (mean paired difference ≤ 5%) and incompatible (mean paired difference > 5%). The performance of glucose meter 1 (n = 767) and glucose meter 2 (n = 266) was assessed. The glucose in the PBMs remained homogenized and stable for at least 180 days. Six out of ten pairs had commutable PBMs. Commutability of PBMs was observed in both well-compatible and incompatible glucose results. Target glucose values from mass spectrometry were significantly different (p ≤ 0.05) from consensus values in one group of glucose meters. When commutable PBMs were used, glucose meter 1 showed better performance than glucose meter 2, and the percentage of satisfaction was associated when using target values for glucose from mass spectrometry and consensus values, but the performance of glucose meter 2 was not associated. PBM from a fixed-cell method could be mass produced with acceptable homogeneity and stability. Commutability testing of PBMs is required prior to use in the performance evaluation of glucose meters, as the commutability of glucose in the PBMs obtained by a fixed-cell method was variable and depended on the individual glucose meter.

13.
Article in English | MEDLINE | ID: mdl-38670261

ABSTRACT

BACKGROUND: Egg allergy is common and caused by sensitization to ovomucoid and/or ovalbumin. Many egg-allergic patients are able to tolerate eggs baked into other foods, such as muffins. Although heating egg extensively reduces allergens, the effect of other food ingredients on allergenicity of eggs, or the "matrix effect," is less well studied. OBJECTIVE: We aimed to define how food matrices impact the matrix effect in egg allergenicity. METHODS: Enzyme-linked immunosorbent assay was used to quantify ovalbumin and ovomucoid in extracts from various baked egg products: plain baked egg without a matrix, and muffins baked using either wheat flour, rice flour, or a wheat flour/banana puree mix. Allergen-specific immunoglobulin E (IgE)-blocking enzyme-linked immunosorbent assays were performed using the egg product extracts on egg-allergic patient sera to determine whether the amount of extracted egg protein in each extract correlated with how well the extracts could bind patients' egg IgE. RESULTS: Baking eggs in any muffin matrix led to an increase in the amount of extractable ovalbumin and a decrease in the amount of extractable ovomucoid compared with plain baked egg. Compared with wheat muffins, rice muffins had more extractable ovalbumin and wheat/banana muffins had more extractable ovalbumin and ovomucoid. The egg allergens in the extracts were able to block egg-allergic patients' egg IgE. CONCLUSIONS: Food matrices affect egg allergen availability. Patients and families should be advised that substitutions in baked egg muffin recipes can affect the amount of egg allergens in foods and potentially affect the risk of food allergic reaction.

14.
J Food Prot ; 87(6): 100278, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38631420

ABSTRACT

The use of antibiotics in agriculture and livestock poses health risks to consumers. Treatments such as High Hydrostatic Pressure (HHP) have been shown to reduce antibiotic and pesticide residues in food. This study aims to investigate the matrix effect on the effectiveness of HHP on hydrochloride tetracycline (HTC) and sulfathiazole (STZ) residues in spiked food matrices. The effect of viscosity, as well as carbohydrate, protein, and fat content on the effectiveness of HHP on antibiotic residues, was investigated. The studied matrices were full-fat and fat-free bovine milk and model food systems consisting of aqueous solutions of sugars, aqueous solutions of proteins, and oil in water emulsions. Model food systems were also used to study the viscosity effect. These systems consisted of aqueous solutions of honey, aqueous solutions of apple puree, and aqueous solutions of glycerol. The HHP processing (580 MPa, 6 min, 25 °C) took place under industrial conditions. For both antibiotics, the concentration of sugars and proteins was found to affect the effectiveness of treatment. The concentration of oils affected treatment efficacy only for HTC. Reduction of antibiotics by HHP was also affected by the type of carbohydrate and the viscosity. In conclusion, the composition and the viscosity of the food matrix exert a variable effect on the studied antibiotic residues reduction by HHP indicating different underlying mechanisms of the interactions between food constituents and antibiotics under the same process conditions.


Subject(s)
Anti-Bacterial Agents , Hydrostatic Pressure , Anti-Bacterial Agents/pharmacology , Animals , Humans , Cattle , Viscosity , Food Contamination/analysis , Milk/chemistry , Drug Residues
15.
Molecules ; 29(3)2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38338336

ABSTRACT

Some South American countries have ancient traditions that may pose legal problems, such as the consumption of coca leaves, as this can provide positive results for cocaine use after the analysis of biological samples. For this reason, it is necessary to find specific markers that help differentiate legal from illegal consumption, such as tropacocaine, cinnamoylcocaine, and especially hygrine and cuscohygrine. In this work, two techniques for collecting biological samples are compared: the Quantisal® Oral Fluid collection device and passive drooling. Once the samples were collected, they were subjected to solid-phase extraction for subsequent injection into GC-MS. Different validation parameters included in international guides have been studied to evaluate whether the proposed method is valid for the defined purpose, placing special emphasis on the study of the matrix effect and little value on GC-MS analyses. With respect to this parameter, an increase in the signal was found for CUS and t-CIN, but it was not significant for the rest of the substances studied. The recoveries have varied significantly depending on the way of working, being higher when working with standardized areas. After carrying out work with the oral fluid samples collected from laboratory volunteers, the method was applied to two real samples. The results obtained support the need for further research to overcome certain limitations presented by the device.


Subject(s)
Alkaloids , Coca , Cocaine , Humans , Coca/chemistry , Gas Chromatography-Mass Spectrometry , Alkaloids/analysis , Plant Leaves/chemistry
16.
Environ Sci Pollut Res Int ; 31(12): 18826-18841, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38353823

ABSTRACT

In this study, a muti-residue analysis method of 40 pesticides in five different categories of fruits in China was developed based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Five hundred real samples were analyzed and assessed for the dietary exposure risk. The sample treatment method was optimized by comparing four clean-up methods. The matrix effects of different fruits were evaluated. The analytical method was validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision. The results showed that the optimal method was the treatment by clean up with ODS (octadecylsilane) and MgSO4. The matrix effect was the strongest in orange and weakest in apple. The LOD and LOQ of pesticides were 0.04-5.9 µg kg-1 and 0.13-19.5 µg kg-1, respectively. The recoveries at three spiked levels were ranged from 71.2 to 115.2% with the RSDs from 0.1 to 19.6%. Twenty-two pesticides were detected in 500 fruit samples from the major production regions of China, with concentrations ranging from 0.1 to 1930 µg kg-1. A total of 13, 10, 9, 8, and 4 pesticides were detected in peach, orange, grape, apple, and strawberry. Both the acceptable daily intake (ADI) and acute reference dose (ARfD) for all the detected pesticides were lower than 100%, indicating that the dietary intake risks are acceptable and would not pose potential health risks.


Subject(s)
Pesticide Residues , Pesticides , Pesticide Residues/analysis , Fruit/chemistry , Chromatography, Liquid , Tandem Mass Spectrometry/methods , Pesticides/analysis , Risk Assessment , China
17.
Article in English | MEDLINE | ID: mdl-38306956

ABSTRACT

Ion mobility spectrometry (IMS) has a promising application prospect in food surveillance. However, due to the complexity of food matrix and trace levels of pesticide residues, the effective and rapid detection of pesticides by IMS has been a challenge, especially when using electrospray ionization (ESI) as an ion source. In this study, low-temperature partitioning with dispersive solid-phase extraction (LTP-dSPE) was explored and compared with conventional procedures. Both methods were validated for the quantification of eight pesticides in apples, obtaining a limit of detection (LOD) of 0.02-0.12 mg/kg for LTP-dSPE and 0.02-0.09 mg/kg for conventional solid-phase extraction (SPE), lower than those usually stipulated by government legislation in food matrices. For LTP-dSPE, the matrx effect (ME) ranged from -16.3 to -68.6 %, lower than that for the SPE method, ranging from -70.0 to -92.9 %. The results showed satisfactory efficiency and precision, with recovery values ranging from 67.9 to 115.4 % for LTP-dSPE and from 62.0 to 114.8 % for conventional SPE, with relative standard deviations below 13.0 %. Notably, the proposed LTP-dSPE/ESI-IMS has been shown to be more cost-effective, easier to use, more environment-friendly, more accessible, and, most importantly, less matrix effect than the conventional method, thereby being suitably applicable to a wide range of food safety applications.


Subject(s)
Malus , Pesticide Residues , Pesticides , Pesticides/analysis , Tandem Mass Spectrometry/methods , Temperature , Pesticide Residues/analysis , Ion Mobility Spectrometry , Solid Phase Extraction/methods
18.
J Am Soc Mass Spectrom ; 35(3): 590-602, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38379502

ABSTRACT

Untargeted metabolomics based on reverse phase LC-MS (RPLC-MS) plays a crucial role in biomarker discovery across physiological and disease states. Standardizing the development process of untargeted methods requires paying attention to critical factors that are under discussed or easily overlooked, such as injection parameters, performance assessment, and matrix effect evaluation. In this study, we developed an untargeted metabolomics method for plasma and fecal samples with the optimization and evaluation of these factors. Our results showed that optimizing the reconstitution solvent and sample injection amount was critical for achieving the balance between metabolites coverage and signal linearity. Method validation with representative stable isotopically labeled standards (SILs) provided insights into the analytical performance evaluation of our method. To tackle the issue of the matrix effect, we implemented a postcolumn infusion (PCI) approach to monitor the overall absolute matrix effect (AME) and relative matrix effect (RME). The monitoring revealed distinct AME and RME profiles in plasma and feces. Comparing RME data obtained for SILs through postextraction spiking with those monitored using PCI compounds demonstrated the comparability of these two methods for RME assessment. Therefore, we applied the PCI approach to predict the RME of 305 target compounds covered in our in-house library and found that targets detected in the negative polarity were more vulnerable to the RME, regardless of the sample matrix. Given the value of this PCI approach in identifying the strengths and weaknesses of our method in terms of the matrix effect, we recommend implementing a PCI approach during method development and applying it routinely in untargeted metabolomics.


Subject(s)
Liquid Chromatography-Mass Spectrometry , Tandem Mass Spectrometry , Chromatography, Liquid/methods , Metabolomics/methods , Feces
19.
Crit Rev Anal Chem ; : 1-25, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38300174

ABSTRACT

Withanolides are the class of steroidal molecules getting greater emphasis in recent years. Quality control throughout the manufacturing and storage period is often one of the key problems that have restricted their broad use in India's indigenous and Ayurvedic medical systems for thousands of years. Because of their diverse clinical potential, withanolides have received a great deal of scientific attention. Analytical techniques are being devised for the automated isolation, identification, and estimation of every single protein within the cell as well as in herbal extracts of withanolides, due to which now researchers are interested in determining the effects of metabolism as well as various stimuli on protein expression, which made the study easier. This study discusses the potential use of hyphenated analytical methods that are reliable in understanding the molecular signaling features, proteome evaluation and characterization of withanolides, in addition to examining existing methodological limitations. The choice of analytical techniques for the withanolides analysis, however, relies on the nature of the sample matrix, the aim of the analysis, and the sensitivity of the technique.

20.
J Vet Diagn Invest ; 36(2): 229-237, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38362609

ABSTRACT

A One Health approach has been key to monitoring the COVID-19 pandemic, as human and veterinary medical professionals jointly met the demands for an extraordinary testing effort for SARS-CoV-2. Veterinary diagnostic laboratories continue to monitor SARS-CoV-2 infection in animals, furthering the understanding of zoonotic transmission dynamics between humans and animals. A RT-PCR assay is a primary animal screening tool established within validation and verification guidelines provided by the American Association of Veterinary Laboratory Diagnosticians (AAVLD), World Organisation for Animal Health (WOAH), and the U.S. Food and Drug Administration (FDA). However, differences in sample matrices, RNA extraction methods, instrument platforms, gene targets, and cutoff values may affect test outcomes. Therefore, targeted validation for a new sample matrix used in any PCR assay is critical. We evaluated a COVID-19 assay for the detection of SARS-CoV-2 in feline and canine lung homogenates and oral swab samples. We used the commercial Applied Biosystems MagMAX Viral/Pathogen II (MVP II) nucleic acid isolation kit and TaqPath COVID-19 Combo kit, which are validated for a variety of human samples, including nasopharyngeal and oropharyngeal swab samples. Our masked test showed a high detection rate and no false-positive or false-negative results, supporting sample extension to include feline oral swab samples. Our study is a prime example of One Health, illustrating how a COVID-19 assay designed for human testing can be adapted and used to detect SARS-CoV-2 in oral swab samples from cats and likely dogs, but not lung homogenates.


Subject(s)
COVID-19 , Cat Diseases , Dog Diseases , Animals , Cats , Dogs , Humans , COVID-19/diagnosis , COVID-19/veterinary , SARS-CoV-2 , Pandemics , COVID-19 Testing/veterinary , Clinical Laboratory Techniques/methods , Clinical Laboratory Techniques/veterinary , RNA, Viral/analysis , Lung , Phosphates , Sensitivity and Specificity
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