FOOD CHEMISTRY
·
2024
·
IF 8.5
Shaofeng Yuan,Jian Yang,Xiaoyan Fu,Hang Yu,Yahui Guo,Yunfei Xie,Yuan Xiao,Yuliang Cheng,Weirong Yao
The effect of tannic acid (TA) binding on the thermal degradation of boscalid was studied in this work. The results revealed that TA binding has a significant impact on boscalid degradation. The degradation rate constant of bound boscalid was reduced, and its corresponding half-life was significantly prolonged compared to the free state. Four identical degradation products were detected in both states through UHPLC-Q-TOF-MS, indicating that degradation products were not affected by TA binding. Based on DFT and MS analysis, the degradation pathways of boscalid included hydroxyl substitution of chlorine atoms and cleavage of C N and C C bonds. The toxicity of B2 and B3 exceeded that of boscalid. In summary, the binding of TA and boscalid significantly affected the thermal degradation rate of boscalid while preserving the types of degradation products. This study contributed to a fundamental understanding of the degradation process of bound pesticide residues in complex food matrices.
研究领域:
食品科学
·
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 3
·640
·
IF 4.2
Maoqing Chai,Guangqiang Xu,Rulin Yang,Hongguang Sun,Qinggang Wang
The accumulation of waste plastics has a severe impact on the environment, and therefore, the development of efficient chemical recycling methods has become an extremely important task. In this regard, a new strategy of degradation product-promoted depolymerization process was proposed. UsingN,N′-dimethyl-ethylenediamine (DMEDA) as a depolymerization reagent, an efficient chemical recycling of poly(bisphenol A carbonate) (BPA-PC or PC) material was achieved under mild conditions. The degradation product 1,3-dimethyl-2-imidazolidinone (DMI) was proven to be a critical factor in facilitating the depolymerization process. This strategy does not require catalysts or auxiliary solvents, making it a truly green process. This method improves the recycling efficiency of PC and promotes the development of plastic reutilization.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2022
·
IF 3.571
Houwei Lin,Yinlian Yuan,Tian Hang,Peng Wang,Shijiao Lu,Hang Wang
In recent years, the development and optimization of biodegradable coronary stents have become the research focus of many medical device manufacturers and scientific research institutions since they can be completely degraded and absorbed, and they restore vascular function. However, there is a lack of in situ quantification of these stents spatially in tissue in vivo . In this study, matrix-assisted laser desorption/ionization (MALDI) Fourier transform ion cyclotron resonance (FT ICR) and time-of-flight (TOF) mass spectrometric imaging (MSI) were used to analyze the time-dependent distributions of a biodegradable vascular scaffold, which consisted of copolymers of lactic acid and glycolic acid (PLGA) and its degradation products in cross-sections and longitudinal sections of blood vessels. The MALDI-MSI methods for analyzing the distribution of PLGA and its derivatives in vivo were established by optimizing the conditions of sample pretreatment and mass spectrometry (MS). In order to semi-quantify the contents of PLGA degradation products in blood vessels, self-made stainless-steel and indium tin oxide (ITO) target plates were developed to compare and establish the standard curves for semi-quantitative analysis. The target plate can be placed on the target carrier of MS simultaneously with the conductive slide, which can simultaneously carry out vapor deposition or spray on the substrate, to ensure the parallelism of the pretreatment experiments between the standards and the actual vascular samples. The proposed method provided a powerful tool for evaluating the distributions and degradation process of biological stent materials in the coronary artery, as well as provided technical support for the research and development of degradable biological stents and product optimization.
研究领域:
医学影像学
·
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
APPLIED RADIATION AND ISOTOPES
·
2025
·
IF 1.8
Long Cui,Mengyuan Zhang,Xian Wang,Jun Xi,Liping Cheng,Mingcheng Yang,Dong Zhang,Huili Yan,Xiaojie Chen,Fuyan Zhang,Zehui Si,Xilong Zhao
Acrylamide (AA), a neurotoxic and potentially carcinogenic compound, forms in starch-rich foods during high-temperature processing, raising significant food safety concerns. Effective AA mitigation strategies are essential. Among degradation methods, irradiation is a promising food processing technology that reduces harmful contaminants without compromising food quality. To investigate the effect of irradiation on AA degradation and explore potential degradation mechanisms, this study first established a liquid chromatography-based detection method to detect AA in starch matrices. Starch matrices containing AA were irradiated with 60 Co-γ rays, and the effects of irradiation dose, initial concentration, and moisture content on degradation efficiency were analyzed. Furthermore, high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS) was employed to identify degradation products and elucidate their formation pathways. Results demonstrated that liquid chromatography effectively detected AA in starch matrices. At an initial AA concentration of 1 000 mg/kg and 60% moisture content, a 2 kGy irradiation dose achieved a 99.12% degradation rate. Total ion chromatogram analysis identified 17 degradation compounds, with five key products primarily formed through graft polymerization reactions between AA and glucose in the starch matrix. In conclusion, optimized 60 Co-γ irradiation effectively degrades AA in starch-based food matrices while generating specific degradation products. These findings offer valuable insights into applying irradiation technology to reduce AA, providing an important reference for enhancing food safety control strategies.
研究领域:
食品安全
·
食品科学
·
辐射生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Boyin Yan,Zhiquan Liu,Ying Liu,Rui Huang,Yongpeng Xu,Dongmei Liu,Fuyi Cui,Wenxin Shi
β- N -Methylamino- l -alanine (BMAA), a new cyanobacterial toxin , is found in different aquatic ecosystems worldwide and is to threaten the human nervous system. Therefore, it is important for water plants to develop feasible methods to counter the effects of BMAA. In this study, the removal of BMAA by chlorine, as well as its intermediate products, at different pH values and the mechanism of pH on the removal BMAA were investigated. The results showed that the chlorination of BMAA is in accordance with the second-order kinetics model. The reaction rate of chlorinated BMAA increased with the increase in the concentration of chlorine. The pH of the solution significantly affected the reaction rate. The apparent kinetic constant ( k app ) decreased from 6.00 × 10 3 M − 1 ·min − 1 to 35.5 M − 1 ·min − 1 when the pH increased from 4.5 to 9 in the chlorine concentration of 32.23 μM. It is probable that the species distribution and proportion of BMAA and chlorine at different pH values were the main causes of this phenomenon. Additionally, the chlorination reaction consisted of four elementary reactions and hydrogen ions were beneficial to the reaction. The temperature also affected the reaction rate and the activation energy of the reaction was 16.6 ± 1.99 kJ·M − 1 . A variety of degradation products were detected and the path of degradation was speculated. Chlorination, dechlorination , and decarboxylation were the main processes of oxidative degradation. Furthermore, the composition of the degradation products was the same at different pH values.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PACKAGING TECHNOLOGY AND SCIENCE
·
2018
·Vol. 31
·期 10
·679-688
·
IF 1.808
Yan Yan,Chang-Ying Hu,Zhi-Wei Wang,Zi-Wei Jiang
Food contact materials contain non-intentionally added substances from degradation, and reaction processes could rise food safety problems. Three polypropylene random copolymer composite films were prepared by extruding the polypropylene random copolymer matrix with Irgafos 168, Irgafos 168 and nanocopper, Irgafos 168 and KH550 modified nanocooper, respectively. To evaluate the degradation behaviors of Irgafos 168, the films were treated by UV irradiation, microwave treatment, sunlight exposure, placed in different oxygen concentration conditions, suffered the extrusion process, and high temperature. Migration test was conducted at 20°C, 40°C, and 70°C with films tested in food simulant. GC-MS was adopted to determine the concentration of Irgafos 168 and its two degradation products, 2,4-di-tert-butylphenol (DP1) and tris (2,4-di-tert-butylphenyl) phosphate (DP2). UV irradiation significantly accelerated the degradation of Irgafos 168 compared with other treatments; DP1 and DP2 increased to maximum value at 24 hours and decreased afterwards, simultaneously. The introduction of nanocopper notably promoted DP1 generation after extrusion whereas suppressed DP2 generation which also caused a higher degradation rate of Irgafos 168 and sharp decrease of DP1 under microwave treatment, sunlight exposure, and high temperature treatment. No significant difference between the effects of nanocopper and KH550 modified nanocopper on degradation of Irgafos 168 was found. For the migration test, the introduction of nanocopper inhibited the migration of Irgafos 168 and DP2 whereas promoted the migration of DP1. No significant difference between the introduction of nanocopper and KH550 modified nanocopper on migration of Irgafos 168 and DP1, DP2 was found.
研究领域:
食品安全
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2022
·
IF 3.571
Jing Jiang,Zhao-liang Hu,Hamza Boucetta,Jia-ming Liu,Min Song,Tai-jun Hang,Yu-ting Lu
Flumazenil is an imidazobenzodiazepine derivative that antagonizes the actions of benzodiazepines . The degradation pathway elucidation plays an important role in the drug quality control. In this work, a reliable LC-Q-TOF/MS method was developed to separate and identify the degradation products of flumazenil generated in the stress testing conducted according to the ICH Q1A(R2) guideline. Fifteen degradation products were detected in total including three reported impurities and twelve unknown impurities. Based on the chromatographic and mass spectrometric data acquired, the structures of all the degradation products were identified. Besides, two major degradants were synthetized and further confirmed by NMR. The degradation pathways of flumazenil were elucidated, and the degradation characteristics of benzodiazepines were also discussed. The obtained results are of both great importance for the quality control of flumazenil and good reference for the degradation study of other benzodiazepines.
研究领域:
药物化学
·
分析化学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2019
·
IF 2.983
Fábio de Souza Barbosa,Leonardo Capra Pezzi,Marisa Tsao,Sandra Manoela Dias Macedo,Tiago Franco de Oliveira,Elfrides E.S. Schapoval,Andreas S.L. Mendez
An ESI-MS/MS method through direct infusion was validated for quantitative analysis of meropenem powder for injection. The validation parameters were established in a rapid analysis of 30 s. Drug stability was studied through the submission to stress testing, resulting on four degradation products. Under hydrolytic conditions, in acid, neutral and alkaline media, the major degradation product was formed through the cleavage of the β-lactam ring. Oxidation of the drug using H 2 O 2 (3%) showed the formation of two degradation products from a decarboxylation reaction and N-oxide formation. Under high humidity conditions, there was detected a dimer product. The stability of meropenem after reconstitution was studied in conditions that simulate its clinical use. In samples reconstituted and diluted in infusion fluids, an extensive degradation was observed. At room temperature meropenem maintained its content > 90% for up to 4 h when prepared in 5% glucose and for up to 12 h when prepared in 0.9% NaCl. Through ESI-MS/MS analyzes it was observed a degradation product formed by β-lactam ring cleavage, detected in all conditions studied. It was also identified a degradation product formed only in 5% glucose, generated by the hydrolysis of β-lactam followed by the attachment of a glucose molecule to the nitrogen of the pyrrolidine ring. In general, all the results obtained in the stability studies contribute to the knowledge about this antibiotic and future candidates of this class.
研究领域:
药学
·
分析化学
·
药物代谢
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Jie Tian,Beibei Li,Ruijuan Qu,Dongmei Zhou,Cheng Sun,Zunyao Wang,Feng Zhu
In this article, the degradation of 4, 4’-(hexafluoroisopropylidene) diphenol (bisphenol AF, BPAF) by ozone was studied and toxicity of the degradation products was evaluated. Kinetic studies showed that acidic conditions were more conducive to the ozone degradation of BPAF than alkaline conditions. In the presence of common anions, Br − and SO 4 2− promoted the degradation of BPAF, whereas NO 2 − , NO 3 − , HSO 3 − inhibited the degradation, and the other anions and cations had no significant effect. The degradation products were analyzed by mass spectrometry, and were mainly manifested in hydroxylation, carboxylation and cleavage of benzene ring. The addition of NO 2 − , HSO 3 − and Br − produced the corresponding free radicals , resulting in the parent compound being attacked and affecting the degradation efficiency and pathways. The theoretical calculated results showed that the ortho-site of the BPAF phenolic hydroxyl group was more active than the meta-position, and it's more likely for free radicals to attack ortho-sites and initiate substitution reactions. Toxicity assessment of the products in the process of ozone degradation showed that toxicity of the products was reduced by benzene ring cleavage and a reduction in the F atomic number. However, the toxicity of nitro and brominated products of BPAF was increased. These findings provide some new insights into the role of common ions in ozonation process and product formation, and supplement the existing conclusions. The results of this study remind future researchers to concern that inorganic ions in real water may be converted into corresponding free radicals that affect the formation of ozone oxidation products.
研究领域:
环境科学
·
化学
·
毒理学
✓ 已验证
DOI
高影响因子
AQUATIC TOXICOLOGY
·
2024
·
IF 4.1
Jiping Li,Wei Li,Naisen Liu,Chenggong Du
The photodegradation products (PDPs) of antibiotics in the aquatic environment received increasing concern, but their chronic effects on microalgae remain unclear. This study initially focused on examining the acute effects of erythromycin (ERY), then explored the chronic impacts of ERY PDPs on Chlorella pyrenoidosa . ERY of 4.0 − 32 mg/L ERY notably inhibited the cell growth and chlorophyll synthesis. The determined 96 h median effective concentration of ERY to C. pyrenoidosa was 11.78 mg/L. Higher concentrations of ERY induced more serious oxidative damage, antioxidant enzymes alleviated the oxidative stress. 6 PDPs (PDP749, PDP747, PDP719, PDP715, PDP701 and PDP557) were identified in the photodegradation process of ERY. The predicted combined toxicity of PDPs increased in the first 3 h, then decreased. Chronic exposure showed a gradual decreasing inhibition on microalgae growth and chlorophyll content. The acute effect of ERY PDPs manifested as growth stimulation, but the chronic effect manifested as growth inhibition. The malonaldehyde contents decreased with the degradation time of ERY at 7, 14 and 21 d. However, the malonaldehyde contents of ERY PDPs treatments were elevated compared to those in the control group after 21 d. Risk assessment still need to consider the potential toxicity of degradation products under long-term exposure.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2019
·
IF 2.983
Jinsheng Lin,Tianpei Huang,Mengxue Feng,Dan Li,Danna Zhao,Jichao Wang,Jianyang Jin,Wenquan Zhu,Min Li
During the related substances testing of mirabegron extended release tablets, an unknown peak was observed in HPLC chromatograms in a level exceeding the identification threshold. By using a strategy that combines LC–PDA/UV-MS n with mechanism-based stress studies, the unknown peak was rapidly identified as cyanomethyl mirabegron, a solution degradant that is caused by a Strecker-like reaction between the API, formaldehyde (an impurity in PEG), and HCN (an impurity in HPLC grade acetonitrile). The mechanism of the solution degradation chemistry was verified by stressing mirabegron with formaldehyde and trimethylsilyl cyanide (TMSCN, a synthetic reagent that generates HCN upon contact with water), in which the secondary amine group of mirabegron first reacts with formaldehyde to form the iminium ion intermediate; the latter then undergoes a nucleophilic attack by cyanide to yield the cyanomethyl mirabegron. The structure of the impurity was further confirmed through the synthesis of the impurity and subsequent structure characterization by 1D and 2D NMR. Due to the ubiquitous presence of formaldehyde in pharmaceutical excipients (e.g., PEG and polysorbate) and trace amount of HCN in HPLC grade acetonitrile, this type of solution degradation would likely occur in sample preparations of pharmaceutical finished products containing APIs with primary and secondary amine moieties. In a GMP environment, such an event may trigger undesirable out-of-specification (OOS) investigations; the results of this paper should help resolve such OOS investigations or even prevent these events from happening in the first place.
研究领域:
药物化学
·
分析化学
·
制药工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2016
·
IF 3.698
Yingjie Li,Qingnan Liu,Wenfeng Li,Yingzhou Lu,Hong Meng,Chunxi Li
Mechanochemical destruction (MCD) is a good alternative to traditional incineration for the destruction of persistent organic pollutants (POPs), like hexachlorobenzene (HCB), and the key is to find an efficient co-milling reagent. Toward this aim, HCB was milled with various reagents in a planetary ball mill at room temperature, and CaC 2 was found to be the best one. HCB can be destroyed completely within 20 min at a mass ratio of CaC 2 /HCB = 0.9 and a rotation speed of 300 rpm. The ground samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy . The results show that the destruction products are nonhazardous CaCl 2 and carbon material with both crystalline and amorphous structures. On these bases, possible reaction pathways were proposed. Considering its excellent efficiency and safety, CaC 2 may be the most feasible co-milling regent for MCD treatment of HCB. Further, the results are instructive for the destruction of other POPs.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）