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Objective: An ultra-high liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-QTOF-MS) was established and applied for the screening and quantitation of pesticide residues in raw milk and infant and young children formula milk powder. Methods: A stable and reliable pretreatment procedure involving quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and Captiva EMR-lipid cleanup was developed and validated. The samples were separated on a Luna Omega Polar C18 (2.1 mm × 100 mm, 1.6 μm) by gradient elution using mobile phase A consisting of 2 mmol/L ammonium formate and 0.01% formic acid and mobile phase B consisting of 2 mmol/L ammonium formate and 0.01% formic acid. By analyzing commercial pesticide certified reference materials, a single injection method using two fragmentation techniques, collision-induced dissociation (CID) and electron activated dissociation (EAD) was developed for the simultaneous qualitative screening and quantitative analysis of 500 pesticide compounds, in which mass spectrometry data were collected using the Zeno sequential window acquisition of all theoretical fragment ion spectra (SWATH) data-independent acquisition (DIA) mode. Comprehensive scores obtained by the OS software from four factors, including mass deviation, retention time deviation, differential isotope ratio and spectrum library similarity, were used for qualitative screening. The matrix-matched external standard method was used for quantitative analysis based on the peak area of precursor ions in the extracted ion chromatogram (XIC). Results: The comprehensive scores of the 500 pesticides and their metabolites ranged from 90.4 to 99.4 points, higher than the minimum score of qualitative screening (90 points), and the limits of detection (LOD) were in the range of 0.025–0.5 μg/kg. The correlation coefficients (r2) of the matrix-matched calibration curves for 103 pesticides and their metabolites with maximum residue limits (MRL) in milk set by the national standard of China GB 2763-2021 were above 0.99. The average recoveries ranged from 72.7% to 114.5% at three spiked concentration levels with relative standard deviations (RSDs) of 2.1%–13.6% (n = 6), and the limits of quantitation (LOQ) were in the range of 0.15–3 μg/kg. Conclusion: This method was sensitive and accurate, and could be used for the screening identification of multiple pesticides and their metabolites and the quantitative analysis of restricted pesticides with high detection rate in raw milk and infant formula milk powder at low cost.

The aim of individuals consuming health supplements is to attain a robust state through nutritional regulation. However, some unscrupulous manufacturers, motivated by profit, fraudulently incorporate drugs or unauthorized components with therapeutic effects into the product for instant product performance enhancement. The long-term use of these products may inadvertently inflict harm on human health and fail to promote nutritive healthcare. The illegal inclusion of these substances is prevalent in kidney-tonifying and sexuality-enhancing products. Developing effective analytical methods to identify these products and screen for illegal added ingredients can effectively prevent such products from reaching and remaining on the market. A target screening method for the detection and quantification of 90 phosphodiesterase type 5 inhibitors (PDE-5is) in 5 kinds of health products was developed and validated. The type of dietary supplements varied from tablets, capsules, and protein powder to wine and beverages. Sample preparation was completed with a one-step liquid phase extraction. The screening process of 90 PDE-5is was done efficiently within 25 min by ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) using the dynamic multiple reaction monitoring (dMRM) technique. The LODs of 90 PDE-5is were detected at levels ranging from 25 to 85 ng/g or ng/mL. This novel targeting methodology was effective and can be applied to routine market supervision. Among 286 batches of samples, 8 batches were found to be positive. Three kinds of PDE-5is were first detected in healthy products. The screening method demonstrated herein will be a promising and powerful tool for rapid screening of PDE-5is. [ABSTRACT FROM AUTHOR]

Naturally occurring substances and their derivatives function as vital resources for pesticides that can be used in fields, such as insecticide production and fungicide development. As a botanical entity displaying multifaceted biological functions, wormwood has received thorough scrutiny across multiple sectors. The insect repellency potency combined with antibacterial and antifungal activities of wormwood position it as a potential candidate for prospective development into eco-friendly chemical pesticides. In this research, Wormwood essential oil was procured via ethanol water under ultrasonic scenarios and subsequently diluted with PEG 400 to formulate green chemical pesticides. The defensive efficacy of this green pesticide on plants was validated through 2 weeks of clustered plant growth experiments. Active constituents that exerted their effects were scrutinized by GC-MS. Furthermore, this green pesticide also displays efficacious effects on the prevention and management of aphids, exhibiting a dose-dependent relationship. 4-terpenol, eucalyptol, carvacrol, and L-borneol were identified by GC-MS as the predominant active constituents in this green chemical pesticide. Wormwood can be leveraged to develop green chemical pesticides, which can protect plants without contaminating the environment. [ABSTRACT FROM AUTHOR]

Mycotoxins are a class of exogenous metabolites that are major contributors to foodborne diseases and pose a potential threat to human health. However, little attention has been paid to trace mycotoxin co-exposure situations in vivo. To address this, we devised a novel analytical strategy, both highly sensitive and comprehensive, for quantifying 67 mycotoxins in human plasma samples. This method employs isotope dilution mass spectrometry (IDMS) for approximately 40% of the analytes and utilizes internal standard quantification for the rest. The mycotoxins were classified into three categories according to their physicochemical properties, facilitating the optimization of extraction and detection parameters to improve analytical performance. The lowest limits of detection and quantitation were 0.001–0.5 μg/L and 0.002–1 μg/L, respectively, the intra-day precision ranged from 1.8% to 11.9% RSD, and the intra-day trueness ranged from 82.7–116.6% for all mycotoxins except Ecl, DH-LYS, PCA, and EnA (66.4–129.8%), showing good analytical performance of the method for biomonitoring. A total of 40 mycotoxins (including 24 emerging mycotoxins) were detected in 184 plasma samples (89 from infertile males and 95 from healthy males) using the proposed method, emphasizing the widespread exposure of humans to both traditional and emerging mycotoxins. The most frequently detected mycotoxins were ochratoxin A, ochratoxin B, enniatin B, and citrinin. The incidence of exposure to multiple mycotoxins was significantly higher in infertile males than in healthy subjects, particularly levels of ochratoxin A, ochratoxin B, and citrinin, which were significantly increased. It is necessary to carry out more extensive biological monitoring to provide data support for further study of the relationship between mycotoxins and male infertility. [ABSTRACT FROM AUTHOR]

With increasing health awareness and the accelerating pace of life, whole-grain prepared foods have gained popularity due to their health benefits and convenience. However, the potential risk of type B trichothecene toxins has also increased, and these mycotoxins in such foods are rarely regulated. In this study, a quantitative method combining a single-valve dual-column automatic online solid-phase extraction system with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed for the first time using restricted-access media columns. This method can simultaneously determine trace residues of seven type B trichothecenes within 15 min. The method is convenient, sensitive (limit of detection and quantification of 0.05–0.6 μg/kg and 0.15–2 μg/kg, respectively), accurate (recovery rates of 90.3%–106.6%, relative standard deviation < 4.3%), and robust (>1000 times). The established method was applied to 160 prepared food samples of eight categories sold in China. At least one toxin was detected in 70% of the samples. Whole-wheat dumpling wrappers had the highest contamination rate (95%) and the highest total content of type B trichothecenes in a single sample (2077.3 μg/kg). Exposure risk assessment indicated that the contamination of whole-grain prepared foods has been underestimated. The total health risk index of whole-wheat dumpling wrappers, which are susceptible to deoxynivalenol, reached 136.41%, posing a significant threat to human health. Effective measures urgently need to be taken to control this risk. [ABSTRACT FROM AUTHOR]

Featured Application: This research developed three cost-effective testing techniques to quickly and efficiently detect suspected samples to determine the authenticity of cosmetics utilizing MALDI-TOF, GC-MS and mid-IR instruments. (1) Background: The adulteration of cosmetics has become increasingly common, which seriously harms ordinary consumers. The counterfeit cosmetics pointed out in this study mainly refer to imitating genuine products in terms of ingredients and packaging. Ordinary consumers cannot distinguish their authenticity solely based on appearance and daily use. If there is a convenient and low-cost detection method that can expose this phenomenon of adulteration, it will be able to expose adulteration and protect the interests of consumers quickly and conveniently. (2) Methods: MALDI-TOF, GC-MS, and mid-IR were used to develop low-cost and fast methods for identifying the authenticity of cosmetics. Five types of liquid and five types of emulsion cosmetics purchased from container and wholesale markets were analyzed using the three instruments mentioned above, and their spectra and acquired data were carefully compared to determine their authenticity. MALDI-TOF and GC-MS directly tested cosmetic samples, and mid-IR spectroscopy tested the ink on the outer packaging of cosmetics. (3) Results: The data procured by MALDI-TOF can provide a representation of its product attributes; two liquid samples and one paste sample demonstrated inconsistent test outcomes with the corresponding reference samples, suggesting contamination. The results of GC-MS can illustrate the substance count within cosmetic samples; the comparison outcomes of the total ion chromatogram indicate that one paste sample was a counterfeit. The results attained from mid-IR were consonant with those acquired from the MALDI-TOF analysis and GC-MS. (4) Conclusions: These three newly developed techniques can all be effectively utilized for the task of detecting cosmetic adulteration and quality control in the manufacturing process. With regard to user-friendliness and rapidity, both MALDI-TOF and mid-IR outperform GC-MS, demonstrating consistently superior levels of detection. Conversely, GC-MS has unique advantages in identifying emulsion cosmetics containing a high amount of weak polarity and volatile substances. Consequently, these corresponding methods could serve as efficient and cost-effective ways to detect authenticity issues in real-world cosmetic products. [ABSTRACT FROM AUTHOR]

The preparation and treatment of the sample has become an important part of the determination process, which directly affects the accuracy of detection. The preparation of the sample for final detection is actually a process of separation and transfer of the target to be tested from the sample matrix. The phase-transfer process of analysis and detection is the process of transferring the target substance to be measured from a complex multiphase system to a simple homogeneous system. This study shows a new phase-transfer process for food sample pretreatment in the determination of carbamate pesticides. Edible gum, xanthan gum, carrageenan, and gelatin were selected for purification testing from the perspective of eco-friendliness and safety. Phase-transfer purification process research was carried out on spinach and other foods. Compared with the commonly used QuEChERS method, the LC/MS results indicate that the straightforward carrageenan treatment process can significantly diminish the detection matrix effect and yield similarly superior detection parameters. The phase-transfer purification method with carrageenan has similar sensitivity and systematic error. The limits of detection and limits of quantitation of each pesticide compound in six plant sample substrates were 0.02–0.36 μg/kg and 0.06–1.9 μg/kg, respectively, which were lower than the residue limits here and abroad. Supplemental recoveries in six blank samples at 5, 20, and 100 μg/kg with the phase-transfer process method were better than those for the QuEChERS method. Positive determination results of actual samples using carrageenan phase-transfer purification proved that this method can be used for related detection from a practical point of view. [ABSTRACT FROM AUTHOR]

In order to improve the risk identification ability of the technical support system of food safety supervision, an online screening platform for food risk substances (hereafter referred to as "platform") was established. The platform aims at the qualitative analysis of unknown compounds and consists of three parts: a standard spectrum library, screening model, and online comparison module. The standard library contains the standard spectra of 527 food risk substances by high-performance liquid chromatography/high-resolution mass spectrometry. The screening comparison algorithm, the core of the screening model, is obtained through the improvement of the existing spectral library search algorithm. The inspector uploads the original spectrum file through the online comparison module; the online comparison module calls the corresponding script to convert the original spectrum file into a standard spectrum file and then uses the screening and comparison algorithm to achieve online real-time comparison. The comparison results are used to determine whether the sample to be tested contains the food risk substances contained in the standard library, so as to realize the preliminary screening of potential food risk substances. The platform supports the spectrogram data format of mainstream instrument manufacturers. The standard spectrogram database can be coconstructed and shared by cooperative laboratories to effectively enrich the types of food risk substances. Through laboratory comparison, data calibration, and model optimization, the screening accuracy of the platform can reach more than 97%. The platform adopts the Internet online screening method, which greatly facilitates the risk investigation and control of national food safety inspection and testing institutions. At the same time, the construction of the screening platform for food risk substances based on high-performance liquid chromatography/high-resolution mass spectrometry, the Internet, big data, and other technologies will provide a new technical means for food safety risk management and control. Hence, it can build a bridge between the screening of risk substances and illegally added substances, as well as risk assessment, risk management, and control. [ABSTRACT FROM AUTHOR]

Food safety remains a matter of great concern in most countries and the composition in food is crucial to food safety. It is very important to make sense of the quality and change of food ingredients. In this research, the change of γ-butyrolactone (GBL), one kind of food additive in beverage, had been evaluated by nuclear magnetic resonance (NMR) technique. The 1H-NMR results of seven beverages covering various kinds with spiked GBL indicated that GBL was transformed into dangerous γ-hydroxybutyric acid (GHB) in six popular beverages under certain conditions which could happen during transportation and storage. Further results of quantitative 13C-NMR showed that pH and temperature were two key factors affecting the transforming degree of GBL to GHB. Lower pH and higher temperature will increase the degree of transformation. GHB was a neurotransmitter on the chemical control list, which was absolutely forbidden to be added to food. This nondestructive NMR detecting technology which did not need the complex pretreatment method to directly determine food ingredients can be useful for identifying the risk of food safety from the changes of food composition during transport and storage. [ABSTRACT FROM AUTHOR]

γ-Hydroxybutyrate (GHB) is a neurotransmitter, which exhibits a strong central nervous system depressant effect. The abuse of GHB or its precursor substances (γ-butyrolactone (GBL) and 1,4-butanediol (1,4-BD)) may cause serious problems. This study developed a fast and effective UHPLC-MS/MS method for the simultaneous quantification of GHB, GBL, and 1,4-BD in four popular beverages, including carbonated drinks, tea, apple cider vinegar, and coffee. The established method overcomes the influence of the in-source collision-induced dissociation of unstable compounds during quantification. The limits of detection were 0.2 μg/mL for GBL and 0.5 μg/mL for GHB and 1,4-BD with excellent linearity in the range of 0.2–50 μg/mL. The recoveries of the three compounds at three spiked levels (2.5, 5.0, and 10.0 μg/mL) in the four kinds of beverages studied were between 90 and 110%, while the relative standard deviations (RSDs) were all <10%. The matrix effect was negligible using this simple and appropriate preprocessed procedure. The method established in this study can quickly and reliably detect the GHB content and its analogues in beverages. [ABSTRACT FROM AUTHOR]

Polyphenols are powerful antioxidants implicated in reducing the risk of human cancer and cardiovascular disease. Chlorogenic acid is a principal polyphenol in coffee, a beverage consumed worldwide on an immense scale. In many countries, coffee is consumed with milk, which has been shown to affect the bioavailability of polyphenols. Here we assessed the interactions of chlorogenic acid with five major milk proteins (α-casein,β-casein,κ-casein,α-lactalbumin, andβ-lactoglobulin) by spectroscopy and molecular docking calculations. The data showed that the number of binding sites in each chlorogenic acid–milk protein complex was close to 1. Fluorescence quenching of milk proteins by chlorogenic acid occurred through a static mechanism and the binding distance was smaller than 8 nm. Binding constant for chlorogenic acid–β-lactoglobulin was larger than those for chlorogenic acid-α-lactalbumin, chlorogenic acid–α-casein, chlorogenic acid–β-casein, and chlorogenic acid–κ-casein. Thermodynamic parameters revealed that Van der Waals forces and hydrogen bond interactions predominated in chlorogenic acid–α-casein and chlorogenic acid–α-lactalbumin complexes; hydrophobic interactions were predominant in chlorogenic acid–β-casein, chlorogenic acid–κ-casein, and chlorogenic acid–β-lactoglobulin. Molecular docking calculations identified chlorogenic acid was located near Pse66, Ile65, and Pro29 in the chlorogenic acid–α-casein adduct, Leu138, Thr126, Gln123, Ser124, Gln167, Ser166, Ser168 in the chlorogenic acid–β-casein adduct, Glu147, Asn123, Val143, Pse149, Pro120, Leu79, Ala148 in the chlorogenic acid–κ-casein adduct, Glu49, Tyr103, Gln54, His32, Trp104, Leu110 in the chlorogenic acid–α-lactalbumin adduct, and Cys66, Leu22, Lys60, Trp61, Ser21, Lys69, Gln59 in the chlorogenic acid–β-lactoglobulin adduct. Notably, the antioxidant activity of chlorogenic acid decreased significantly on interaction with each of the milk proteins (p < 0.05). This study reveals the binding behaviors of chlorogenic acid with five milk proteins and provides basic data that can help to clarify the binding mechanism. [ABSTRACT FROM PUBLISHER]

The effects of lactose on the changes in the composition and size of casein micelles induced by high-pressure treatment and the related mechanism of action were investigated. Dispersions of ultracentrifuged casein micelle pellets with 0–10% (w/v) lactose were subjected to high pressure (400 MPa) at 20 °C for 40 min. The results indicated that the level of non-sedimentable caseins was positively related to the amount of lactose added prior to pressure treatment, and negatively correlated to the size. A mechanism for the pressure-induced, lactose-dependent changes in the casein micelles is proposed. Lactose inhibits the hydrophobic interactions between the micellar fragments during or after pressure release, through the hydrophilic layer formed by their hydrogen bonds around the micellar fragments. In addition, lactose does not favour the association between calcium and the casein aggregates after pressure release. Due to these two functions, lactose inhibited the formation of larger micelles after pressure treatment. [ABSTRACT FROM AUTHOR]

Authors' Contributions Ding Hong, Cao Jin, Hu Kang, and Jin Shaoming jointly studied and formulated research ideas, technical solutions, and verification implementation. Kang Hu and Shaoming Jin wrote and prepared the original draft. In the article titled "The Bridge between Screening and Assessment: Establishment and Application of Online Screening Platform for Food Risk Substances" [[1]], the Authors' Contributions statement was omitted. [Extracted from the article]

Folic acid has been widely introduced into nano-drug delivery systems to give nanoparticle-targeted characteristics. However, the poor water solubility of folic acid may hinder the exploitation of its ability to load antineoplastic drugs. In the present study, we designed a new folate derivative (FA-2-DG) synthesized from folic acid and 2-Deoxyglucose (2-DG). The aim of this study was to evaluate the self-assembly characteristics of FA-2-DG, and its ability of loading cisplatin. The critical micelle concentration was 7.94 × 10−6 mol L−1. Fourier transform infrared spectroscopy indicated that hydrogen bonding interaction is a main driving force for the self–assembly of FA-2-DG. The particle was stable in pure water or 0.5% bovine serum albumin dispersions. By forming a coordination bond, the particles assembled from FA-2-DG can load cisplatin. The loading efficiency was maximal when the molar ratio of FA-2-DG to cisplatin was 2:1. [ABSTRACT FROM AUTHOR]

The glucose analog, 2-deoxyglucose (2-DG), specifically inhibits glycolysis of cancer cells and interferes with the growth of cancer cells. However, the excellent water solubility of 2-DG makes it difficult to be concentrated in tumor cells. In this study, a targeted nano-pharmacosome was developed with folic acid-modified 2-DG (FA-2-DG) by using amino ethanol as a cleavable linker. FA-2-DG was able to self-assemble, forming nano-particles with diameters of 10–30 nm. The biological effects were evaluated with cell viability assays and flow cytometry analysis. Compared with a physical mixture of folic acid and 2-DG, FA-2-DG clearly reduced cell viability and resulted in cell cycle arrest. A computational study involving docking simulation suggested that FA-2-DG can dock into the same receptor as folic acid, thus confirming that the structural modification did not affect the targeting performance. The results indicated that the nano-pharmacosome consisting of FA-2-DG can be used for targeting in a nano-drug delivery system. [ABSTRACT FROM AUTHOR]

The analysis of food samples is a challenging task. The high complexity of food matrices hinders the extraction and detection of analytes from them. Therefore, the correct preparation of food samples is a crucial step for their subsequent analysis, as it achieves the proper isolation and preconcentration of analytes and removes the interfering proportion of the food matrix before instrumental analysis. We aimed to develop a method that not only satisfies the requirement of detecting trace compounds in complex matrices but also achieves a "greener" approach by reducing the use of organic solvents and non-degradable materials to minimize the health hazards posed to the operators as well as pollution to the environment. In this study, we prepared egg white as a concentrated gel and used this material for the biological purification of milk samples. After the milk protein was removed by acidification and salting, the residual amount of aflatoxin M1 in milk samples was quantitatively determined by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that the novel egg white purification method possessed advantages over the immunoaffinity technique used as the reference method in extraction recovery, sensitivity, repeatability, and operability. The limit of detection (LOD) was 0.001 μg/kg. In spiked samples containing 0.01 μg/kg to 2 μg/kg of AFM1, the average recovery was 88.3-94.7%, with a precision of 6.1-11.0%. Improved repeatability was obtained by significantly reducing the operation time and resource requirements compared with the immunoaffinity technique currently used internationally. This study provides a reference for the further improvement of the relevant international standards in place for the detection of aflatoxin M1 in milk.

Resistance and nonresponse to aspirin dramatically decreases its therapeutic efficacy. To overcome this issue, a small-molecule thrombus-targeting drug delivery system, aspirin-Arg-Gly-Asp-Val (A-RGDV), is developed by covalently linking Arg-Gly-Asp-Val tetrapeptide with aspirin. The 2D ROESY NMR and ESI-MS spectra support a molecular model of an A-RGDV tetramer. Transmission electron microscopy images suggest that the tetramer spontaneously assembles to nanoparticles (ranging from 5 to 50 nm in diameter) in water. Scanning electron microscopy images and atomic force microscopy images indicate that the smaller nanoparticles of A-RGDV further assemble to bigger particles that are stable in rat blood. The delivery investigation implies that in rat blood A-RGDV is able to keep its molecular integrity, while in a thrombus it releases aspirin. The in vitro antiplatelet aggregation assay suggests that A-RGDV selectively inhibits arachidonic acid induced platelet aggregation. The mechanisms of action probably include releasing aspirin, modifying cyclic oxidase, and decreasing the expression of GPIIb/IIIa. The in vivo assay demonstrates that the effective antithrombotic dose of A-RGDV is 16700-fold lower than the nonresponsive dose of aspirin.