Environmental Science-Processes & Impacts
·
2021
·Vol. 23
·期 10
·1566-1577
·
IF 4.238
Cécilia Siri,Yang Liu,Thibault Masset,William Dudefoi,Dean Oldham,Matteo Minghetti,Dominique Grandjean,Florian Breider
The sorption of hydrophobic organic compounds (HOC) onto microplastics is relatively well reported in the literature, while their desorption remains poorly investigated, especially in biological fluids. The present study investigated the sorption and desorption of progesterone on polyethylene (PE), polypropylene (PP), and polystyrene (PS) microplastics. The sorption experiments showed that the equilibrium was reached in a few hours for all plastics. A sorption efficiency of 357.1 μg g−1 was found for PE and PS, and 322.6 μg g−1 for PP. Sorption experiments indicated that adsorption would certainly happen via surface sorption and a potentially pore-filling mechanism. The desorption was carried out in Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF), whose formulations were more complex than similar models reported so far. It has been found that the desorption was higher in SIF as compared to SGF, due to micelle formation in SIF promoting the pollutant solubilization. The sorption of pepsin onto microplastics has also been revealed, suggesting a competition between pollutants and pepsin for sorption sites and a potent reduction in pollutant solubilization. This study indicates that the ingestion of microplastics could be considered as an additional route of exposure to pollutants and therefore emphasizes pollutant bioavailability for aquatic organisms.
研究领域:
环境科学
·
毒理学
·
生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2021
·
IF 4.464
Meiling Lian,Yuqing Shi,Wei Zhang,Jingbo Zhao,Da Chen
This work reports the synthesis and application of nitrogen and sulfur co-doped Nb 2 C MXene (NS-Nb 2 C) for the sensing of dopamine (DA) in gastric juice. NS-Nb 2 C MXene was successfully synthesized in a one-step treatment of Nb 2 C using thiourea as N,S resource. The heteroatom doping strategy enables introduction of N,S into MXene nanosheets and simultaneously induces the increased interlayer spacing, high surface area, and enhanced electrical conductivity. It was found that NS-Nb 2 C is more electrochemically active than multilayered Nb 2 C nanosheets (ML-Nb 2 C) and delaminated Nb 2 C nanosheets (DL-Nb 2 C). Based on this, the as-prepared NS-Nb 2 C/Nafion/GCE was used to study the electrochemical behavior of dopamine in pH = 3.0. The sensing interface not only utilizes the unique two-dimensional (2D) nanosheet morphology of Nb 2 C that has a larger surface area and conductive network, but also takes advantage of the more active sites provided by doping. This enables the sensor to achieve ultra-sensitive detection of dopamine (S/N = 3) with a low limit of detection (LOD) of 0.12 µM. In addition, the prepared sensor has good stability and selectivity, and the results of detecting DA in simulated gastric juice is satisfactory. The results indicated that the Nb-based MXenes provided a promising tool for acidic electrochemical sensing applications.
研究领域:
材料科学
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电化学传感
·
医学检测
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2011
·Vol. 3
·期 2
·498-503
·
IF 0
Haoxiang Lu,Wei Wang,Zhen Zheng,Peiyu Sun,Xinling Wang,Feng-Chih Chang
Two kinds of novel peptide mimetic pepsin-inspired degradable polyurethanes were synthesized and characterized. A synthetic pseudo tripeptide acted as chain extender and provided active sites for pepsin biodegradation. In vitrodegradation behavior was investigated in simulated gastric fluid containing pepsin, and assessed by 1H NMR, mass loss and SEM. The results indicated that the pseudo peptide bonds in polyurethanes were effectively digested by the action of pepsin. Furthermore, the rate and degree of pepsin-inspired polyurethanes in simulated gastric fluid containing pepsin could be controlled by alteration of the soft segments and activity of pepsin. The influence of the polymers on human umbilical vein endothelial cells was evaluated by WST-1 assay. The results indicated that the polymers sustained much higher cell viability than the controls.
研究领域:
生物材料学
·
高分子化学
·
生物医学工程
✓ 已验证
产品关联
DOI
FOOD HYDROCOLLOIDS
·
2014
·
IF 4.28
Sha Cai,Meng Zhao,Yapeng Fang,Katsuyoshi Nishinari,Glyn O. Phillips,Fatang Jiang
Emulsification/internal gelation is an effective encapsulation method to protect probiotics from adverse environment. In this paper, microcapsules of Lactobacillus acidophilus CGMCC1.2686 were prepared by emulsification and gelation of alginate solutions with slow release of Ca 2+ ions from calcium carbonate (CaCO 3 ) and calcium disodium ethylenediaminetetraacetate (Ca-EDTA). Physical characterization of the two types of microcapsules showed that alginate-Ca-EDTA microcapsule was more uniform in size than alginate-CaCO 3 , with a span factor of 0.96 and 1.20, respectively. Mechanical measurements demonstrated that alginate-CaCO 3 microcapsule was more robust and elastic, which was supported by its denser structure as observed by electron scanning microscopy. Bacteria encapsulation yields in the two microcapsules were similar, 37.9% for alginate-CaCO 3 and 36.9% for alginate-Ca-EDTA. However, alginate-CaCO 3 microcapsule exhibited much higher cell survivals in both simulated gastric juice and bile salts solution (22.2% and 2.6*10 −2 %, respectively) than alginate-Ca-EDTA (7.1% and 0%, respectively), indicating a more effective protection of L. acidophilus CGMCC1.2686. The protection efficiency was discussed in relation to the mechanical properties of the microcapsules and the calcium sources used.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Analytical Chemistry
·
2020
·
IF 1.678
Lina Huang,Hanke Li,Yuhang Li,Peng Ren,Lezhou Yi,Yang Chen,Tongmei Ma
Background. Organic tin compounds (OTCs), a group of high-risk hazardous substances, are highly concerned in safety regulation of consumer products especially for toys because they can cause serious damage to organs after prolonged or repeated exposure. Gastric juice migration is nowadays widely implemented to assess organic tin intake from toys or food-contact materials; however, the followed up detection method using sodium tetraethylborate [NaB(Et4)] as a derivatization agent may directly lead to false positive of monomethyltins (MMT). Objective. In order to avoid the phenomena of false positive of MMT in the course of laboratory testing of toys, it is necessary and important to perform relative experimental and theoretical studies to reveal the cause of false positive of MMT. Method. With metal tin powder as a representative of inorganic tin which existed in real samples, it was treated with artificial gastric juice (0.07 mol/L·HCl), followed by ethyl derivatization using sodium tetraethylborate [NaB(Et)4] and then analyzed by gas chromatography-mass spectrometry (GC-MS) according to the procedure specified in the standard of EN 71-3:2013+A3:2018 issued by the European Committee for Standardization (CEN). Results. Without any OTCs in the starting materials, MMT false positive can be reproduced by detecting 0.56 mg/L of triethylmethyltin (TEMT) together with approximately 1000 mg/L of tetraethyltin (TeET), which is similar to real samples. Further, it is demonstrated that the detected amount of TEMT is linearly related with the added amount of NaB(Et)4, and that the formation of TEMT (methyl derivative) is easier than TeET (ethyl derivative) even though the ethyl group is present in a larger amount than the methyl group. Conclusions. The phenomena of MMT false positive which occurred in the laboratory testing of toys is mainly because that TEMT is highly likely to be obtained from the reaction of inorganic tin and trace level of methylation agent impurities contained in the derivatization reagent—NaB(Et)4. To avoid MMT false positive, it is concluded that the maximum acceptable mole ratio of methylation agent impurities contained in NaB(Et)4 is approximately 0.028%. This research is helpful to be aware of methylation impurities and is favorable to avoid false judgment caused by MMT false positive in routine analysis of toys.
研究领域:
分析化学
·
毒理学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2024
·
IF 11
Nuocheng Xu,Yutong Feng,Huiping Wan,Zilong Li,Keyu Sun,Shuhong Ye
The objective of this research was to formulate a sophisticated probiotic intestinal-targeted delivery system employing GEL (Gelatin) and CMC (Carboxymethyl Cellulose) via intricate complex coacervation and double-emulsion structure. RSM (Response Surface Methodology) screening of cryoprotectants was undertaken and the digestive kinetic characteristics of microcapsules were comprehensively evaluated in simulated in vitro release environment. Upon optimization using response surface design, bacterial suspension was prepared using composite cryoprotectant composed of 3.07 wt% MNT (Mannitol), 4.42 wt% TCP (Taxus cuspidata polysaccharides) and 2.01 wt% GEL, achieving a cell recovery rate of 83.21%, which was 70.8% higher than free cells. The freeze-dried microcapsules presented in a stabilized bilayer system, the cell concentration after encapsulation was 8.66 log CFU/g, with encapsulation efficiency reaching 88.17%, and the particle size distribution concentrated at 299.05 μm/d. GEL and CMC conjugate through the interaction of positive and negative ions to form a complex polymer under pH of 3.5. Deprotonation occurs while pH changes in intestinal environment, enabling controlled release. In vitro release kinetics by Hixson-Crowell was closer than Higuchi model, the survival rate of encapsulated cells reached 83.64% in simulated gastric fluid, representing a 56.15% increase compared to free cells. After 6-weeks of storage in low-humidity environment at −18 °C, the recovery rate remained at 94.59%, representing a 69.17% increase compared to free cells. This research offer guiding principles and insights for future comparable research.
研究领域:
食品科学
·
生物工程
·
药物递送系统
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2022
·
IF 6.556
Xuemei Ma,Jiayi Yu,Lin Wei,Qian Zhao,Liyong Ren,Zhiyong Hu
Simultaneous selective determination of Fe (Ⅱ) and Fe (Ⅲ) is of great significance to the study of iron ion tracking and release of iron supplement in gastric fluid. In this paper, a composite material (N-CQDs/AgNPs/β-CD) was prepared by a one-pot method. The various characterizations confirmed the silver nanoparticles (AgNPs) grew in situ on the surface of nitrogen-doped carbon quantum dots (N-CQDs), and the β-cyclodextrin (β-CD) and AgNPs linked together by Ag–O bonds finally presented gourd-like nanoparticles on the surface of N-CQDs. Then, N-CQDs/AgNPs/β-CD modified glassy carbon electrode (GCE) was applied to detect Fe(II) and Fe(III) simultaneously. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results confirmed that N-CQDs/AgNPs/β-CD enhanced electrode performances because of the synergistic effect between N-CQDs, AgNPs and β-CD. The sensor was successfully applied for the determination by differential pulse voltammetry (DPV) of Fe(II) and Fe(III) released from four iron supplementations in simulated gastric fluid (SGF).
研究领域:
分析化学
·
生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Long Yu,Qutong Zheng,Di Wu,Yuxiu Xiao
pH is of great importance in understanding physiological and pathologic processes. Abnormal gastric juice pH is an indicator of many gastric diseases such as peptic ulcer and gastric cancer. In this work, a nanocomposite 1-hydroxypyrene@ Co/Tb- dipicolinic acid metal-organic framework (1-OHP@Co/Tb-DPA MOF) was constructed as a ratiometric fluorescent pH sensor for strong acidity. The nanocomposite-based pH sensor was response-rapid (30 s), linearly responsive in the broad pH range of 0.3–7.8 ( r > 0.95) and ultra-sensitive in the pH range of 0.3–5.0. Importantly, the nanocomposite-loaded fiber paper was prepared as a visual microsensor for point-of-care pH detection via ratiometric chromaticity, coupled with a homemade portable determination device. The paper-based visual microsensor is response-rapid and sensitive, long-term stable (at least 30 days), and suitable for pH assay of microvolume (as little as 5 μL) samples at pH 0.3–5.0. Both the nanocomposite-based ratiometric fluorescent sensor and the paper-based visual microsensor can accurately determine the pH of artificial gastric juices (relative error <5.4%). To our knowledge, this is the first time to report a MOF-based ratiometric fluorescent pH sensor for strong acidity (pH<1) and a paper-based pH microsensor for point-of-care visual assay via ratiometric chromaticity.
研究领域:
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
AAPS PHARMSCITECH
·
2017
·Vol. 19
·期 3
·1020-1028
·
IF 2.451
Zhou Huanbin,Li Shunyi,Chen Yao,Zhang Qian,Bai Xuequn,Zhu Chune,Liu Hu,Wang Lili,Wu Chuanyu,Pan Xin,Wu Chuanbin
Microencapsulation technology has the potential to protect probiotics and to deliver them to the gut, and extrusion is one of the most commonly used methods. However, the rather large diameters of 1~5 mm produced tend to cause oral grittiness and result in low compliance. In this article, Streptococcus thermophilus IFFI 6038 (IFFI 6038) microcapsules were prepared using an ultra-fine particle processing system (UPPS) previously developed by this research group. IFFI 6038 suspension was pumped by a peristaltic pump to the feeding inlet nozzle and then dispersed into micro-droplets by a rotating disk, followed by solidification. Trehalose (16%) was used as a cryoprotectant to protect IFFI 6038 from damage by lyophilization used in the process. Alginate (3%) resulted in IFFI 6038 microcapsules with a median particle diameter ( d
50 ) of 29.32 ± 0.12 μm and a span value of 1.00 ± 0.02, indicating uniform particle size distribution. To evaluate the potential of microencapsulation in protecting IFFI 6038 from the gastric conditions, the viable counts of IFFI 6038 following incubation of IFFI 6038 microcapsules in simulated gastric juices for 120 min were determined and compared with those of free IFFI 6038. The stability of microencapsulated IFFI 6038 upon storage for 3 months at 4°C and 25°C, respectively, was also determined. The results showed that microcapsules prepared by UPPS protected IFFI 6038 from gastric conditions. The results from a rat diarrhea model showed that microcapsules prepared by the UPPS method were able to effectively improve the diarrhea conditions in rats.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2022
·
IF 7.425
Xin Luo,Siqi Fan,Zhuosui He,Fangfang Ni,Chengzhi Liu,Min Huang,Lei Cai,Gerui Ren,Xuan Zhu,Qunfang Lei,Wenjun Fang,Hujun Xie
Probiotics are sensitive to external conditions, resulting in low survival rates after being ingested or during food production, transportation and storage. In order to improve the survival rate of Lactobacillus plantarum (LP) during gastrointestinal digestion, storage, and freeze-drying, alginate-whey protein isolate (ALG-WPI) and alginate-pectin-whey protein isolate (ALG-PEC-WPI) composites were employed to encapsulate LP. The encapsulation efficiency of ALG-WPI-LP and ALG-PEC-WPI-LP beads both reached more than 99 % . Scanning electron microscopy (SEM) indicated that dense and rough aggregates were formed on the surface of both composites, and attached LP cells could be observed inside the beads. The ALG-WPI and ALG-PEC-WPI composites can protect the viability of LP in simulated gastric fluid (SGF) and release the probiotics in simulated intestinal fluid (SIF). The storage stability of LP at 4 °C was improved by about 15 % in comparison with bare LP and the survival rates of LP in ALG-WPI-LP and ALG-PEC-WPI-LP powders after freeze-drying were increased by 65.37 % and 72.06 %, respectively. The formation mechanism of ALG-WPI and ALG-PEC-WPI composites was further explored by fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The ALG-WPI and ALG-PEC-WPI composites have great potential to protect and deliver probiotics in food systems.
研究领域:
食品科学
·
微生物学
·
生物工程
✓ 已验证
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Jun Ye,Luying Liu,Wu Lan,Jian Xiong
Carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA) hydrogels loaded with soybean peptide (SPE) were fabricated via a freeze-thaw method. These hydrogels conquer barriers in simulated gastric fluid (SGF), and then release SPE in simulated intestinal fluid (SIF). The results of in vitro SPE release from these hydrogels showed that in SGF only a little of the SPE released, but in SIF the SPE was completely released. The released SPE had scavenging rates for DPPH and ABTS free radicals of 41.68 and 31.43 %. The pharmacokinetic model of SPE release from the hydrogels in SIF was studied. When the hydrogels are moved from SGF to SIF, the sorption of the shrinkage hydrogel network is entirely controlled by stress-induced relaxations. There are swollen and shrunken regions during SPE release. For SPE release into the SIF, SPE has to be freed from the weak bonds in the swollen regions by changes in the conformation of CMC and PVA. The release rate of SPE was found to be governed by the diffusion and swelling rate of the shrinkage hydrogel network. The Korsmeyer-Peppas equation diffusion exponents (n) for SPE release from the hydrogels are >2.063, indicating a super case II transport. These data demonstrate CMC/PVA hydrogels have potential applications in oral peptide delivery.
研究领域:
药学
·
材料科学
·
生物技术
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Peng Wang,Zhi-gang Luo,Zhi-gang Xiao
Hydrogel beads composed of oxidized gellan gum (OGG) and resistant starch (RS) were successfully fabricated by ionic cross-linking and used as delivery carriers for resveratrol. Firstly, OGG with different degrees of oxidation were prepared through 2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation, and characterized by Fourier transform infrared spectroscopy and carbon-13 nuclear magnetic resonance to prove that carboxyl groups were successfully introduced into the gellan gum molecules. Molecular weight, thermal stability, zeta potential and gelation temperature of OGG were also investigated. Subsequently, resveratrol was encapsulated into OGG/RS hydrogel beads in the form of resveratrol/β-cyclodextrins inclusion complexes. The addition of RS significantly influenced the morphological structure and swelling capacity of OGG/RS hydrogel beads. The OGG/RS hydrogel beads exhibited a pH-sensitivity and high encapsulation efficiency of resveratrol (84.95 %–90.73 %). Furthermore, the in-vitro release behaviors demonstrated that OGG/RS hydrogel beads showed good stability in simulated gastric fluids and sustained release of resveratrol in simulated intestinal fluids. The obtained results indicate that OGG/RS hydrogel beads show a potential as delivery system for resveratrol in the food industry.
研究领域:
食品科学
·
药学
·
材料科学
✓ 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）