This study developed the polysaccharide-based nanoparticles by the polyelectrolyte complexation between chitosan (CS) and gum arabic (GA) as novel delivery systems for curcumin. Optimization of ...parameters affecting the formulation of such nanocarriers was performed by means of dynamic light scattering and fluorescence analysis. It was demonstrated that at pH 4.0 and 1:1 mixing ratio of CS to GA, the two biopolymers can form hydrophilic, monodisperse and highly positively charged colloidal nanoparticles. Fourier-transform infrared and X-ray diffraction further confirmed their electrostatic interaction. Subsequently, the formulations and stability of nanoparticles loaded with curcumin were compared. The optimum formulation was found to be Tween 80/egg yolk phospholipid (1:1, w/w), curcumin/emulsifier (0.5:5, w/w) and curcumin concentration initially prepared (4%, w/w). The developed nanoparticles showed the average diameter in the range of 250–290 nm. The curcumin encapsulation efficiency and loading content respectively exceeded 90% and 3.8%, with a retention rate higher than 85% during storage. Additionally, whatever the antioxidant model was, the antioxidant activities of curcumin were significantly enhanced by nanoencapsulation. Furthermore, compared to emulsion without biopolymer coating, CS-GA nanoparticles can improve the stability and delay the release of curcumin in a simulated gastrointestinal environment. These findings suggested that CS-GA nanoparticles could be used as an ideal carrier to deliver hydrophobic bioactive ingredients like curcumin in functional foods.
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•CS-GA nanoparticles containing emulsifiers were fabricated as curcumin carriers.•CS-GA nanoparticles can encapsulate, stabilize and deliver curcumin effectively.•Antioxidant activity of curcumin was enhanced by nanoencapsulation.•Release of curcumin from nanoparticles was controlled in gastrointestinal tract.
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•Dextran with 40 kDa endow the glycosylated micelles a better encapsulation ability.•The lutein loaded in glycosylated micelles changed from crystalline to amorphous.•Glycosylated ...casein micelles were more stable to pH and ionic strength.•Lutein burst release in vitro was controlled by glycosylated casein micelles.
Lutein was encapsulated in glycosylated micelles and the controlled delivery property was investigated. The particle size at different pH and CaCl2 concentration showed that the stability of micelles based on glycosylated casein was significantly superior to that of casein/dextran mixture. The bigger molecular weight of the dextran moieties attached to the casein molecules improved the steric hindrance effect. The cumulative release rate showed that lutein could be bound with glycosylated casein in the micelles and uniformly scattered in simulated gastric fluid, while micelles composed of casein and dextran mixtures rapidly disintegrated and released the embedding lutein within 0.5 h. Additionally, micelles based on glycosylated casein significantly increased the bioaccessibility of lutein from 14.63% to 62.45%. Therefore, glycosylated casein via Maillard reaction could be used as the carrier of lutein, which might effectively control its release behavior in the simulated gastrointestinal tract.
Infections like COVID-19 are the primary cause of death around the world because they can cause acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and sepsis. Inflammatory cells ...serve as crucial protective barriers in these diseases. However, excessive accumulation of inflammatory cells is also one of the major causes of organ damage. The non-muscular myosin light chain kinase (nmMLCK) plays crucial of cytoskeletal components involved in endothelial cell-matrix and cell-cell adhesion, integrity, and permeability. Our previous investigations found that ML-7, a specific inhibitor of MLCK, promoted neutrophil apoptosis through various signaling pathways. In this study, we found that knockout of MLCK significantly promote apoptosis of neutrophils and macrophages in the BALF of the LPS-induced ALI, meanwhile it had no effect on the apoptosis of neutrophils in the circulatory system. RNA-sequencing revealed that the effect of MLCK knockout in inducing apoptosis of inflammatory cells was mediated through lysosomes. Administering ML-7 into the lungs significantly promoted neutrophil apoptosis, accelerating their clearance. In the LPS- or CLP-induced sepsis models, ML-7 administration significantly improves the apoptosis of inflammatory cells, especially neutrophils, at the infection site but had no impact on neutrophils in the circulatory system. ML-7 also significantly improved the survival rate of mice with LPS- or CLP-induced sepsis. Taken together, we found that MLCK plays a crucial role in the survival of inflammatory cells at the infection site. Inhibiting MLCK significantly induces apoptosis of inflammatory cells at the infection site, promoting inflammation resolution, with no impact of the circulatory system.
•MLCK activation contributes to the survival of neutrophils in human sepsis.•Ablation of Mlck1 or inhibition of MLCK accelerates the cell death of inflammatory cells but have no effect on normal white blood cells.•Inhibition of MLCK improves the survival of mice with CLP or LPS-induced sepsis.
The flexibility and simplicity of stir bar sorption extraction (SBSE) have been combined with the selectivity of molecularly imprinted polymers (MIP). Stir bars were coated reproducible with a 180
μm ...film formed from a formic acid solution of nylon-6 polymer either nonimprinted or imprinted with monocrotophos. Time sorption profiles were measured for the extraction of monocrotophos from dichloromethane at the concentration of 10–200
μmol/L levels with both types of films in order to compare extraction characteristics. The results indicated that the MIP coated layer showed remarkable high affinity toward monocrotophos and equilibrium adsorption was attained rapidly (60
min) in contrast to free standing molecularly imprinted polymer in which equilibrium adsorption was normally attained after several hours. The stir bars coated with MIP films were capable of extracting four structural analogues of monocrotophos from dichloromethane solution, which suggests that both the amino group and P
O part of these molecules is responsible for interaction with the imprinted polymer. Evidence was also presented by FT-IR analysis that the amide-hydrogen-bonding interaction between the MIP-coated films and monocrotophos was originated for monocrotophos recognition. To achieve selective extraction of monocrotophos from sample, stir bars coated with MIP films were washed with 10% (v/v) acetic acid/methanol and methanol. Clean extracts and yields of 95% were obtained, demonstrating the suitability of stir bar coated with MIP films for the analysis of environmental and biological samples. Compared with traditional MIP and SBSE, the MIP-coated film showed not only the high selectivity but also the rapid equilibrium adsorption.
To facilitate rapid in situ analyte monitoring within heterogeneous samples, a space-resolved solid phase microextraction (SR-SPME) technique was developed that utilized miniaturized segmented ...fibers. Initially, a multilayered agarose gel was used to determine the effects of diffusion-based mass transfer and fiber dimension on the space-resolving capability of SPME. For diazepam within agarose gel, the SR-SPME limit of detection was 2.5 ng/mL, with a linear dynamic range up to 500 ng/mL. The efficacy of the SR-SPME technique was further evaluated within diverse biological matrices (onion bulb, fish muscle, and adipose tissues) containing stratified pharmaceutical analytes. Empirically, the results agreed well with established techniques such as microdialysis and liquid extraction, but SR-SPME was simpler to implement, displayed higher spatial resolution, and was more cost-effective than traditional approaches. Additionally, the segmented design of the SPME fibers and stepwise desorption protocols offer potential advantages within high throughput applications.
An analytical methodology for the analysis of four polar organophophorus pesticides (monocrotophos, mevinphos, phosphamidon, omethoate) in water and soil samples incorporating a molecularly imprinted ...solid-phase extraction (MISPE) process using a monocrotophos-imprinted polymer was developed. Binding study demonstrated that the polymer showed excellent affinity and high selectivity to monocrotophos. The MISPE procedure including the clean-up step to remove any interferences was optimized. The accuracy and selectivity of the MISPE process developed were verified using a non-imprinted (blank) polymer and a classical ENVI-18 cartridge as the SPE matrix during control experiments. The use of MISPE improved the accuracy and precision of the GC method and lowered the limit of detection. The recoveries of four polar organophosphorus pesticides (OPPs) extracted from 1
L of river water at a 100
ng/L spike level were in the range of 77.5–99.1%. The recoveries of organophosphorus pesticides extracted from a 5-g soil sample at the 100
μg/kg level were in the range of 79.3–93.5%. The limit of detection varied from 10 to 32
ng/L in water and from 12 to 34
μg/kg in soil samples. The molecularly imprinted polymer (MIP) enabled the selective extraction of four organophosphorus pesticides successfully from water and soil samples, demonstrating the potential of molecularly imprinted solid-phase extraction for rapid, selective, and cost-effective sample pretreatment.
Chronic obstructive pulmonary disease (COPD) characterized by the airway and lung inflammation, is a leading cause of morbidity and mortality worldwide, especially among smokers over 40 years of age ...and individuals exposed to biomass smoke. Although the detailed mechanisms of this disease remain elusive, there is feasible evidence that protein posttranslational modifications (PTMs) may play a role in its pathoetiology. We thus conducted studies to dissect the effect of cigarette smoke extracts (CSE) on the change of SUMOylated substrates in human bronchial epithelial cells (HBEs).
Samples were collected in HBEs with or without 24 h of CSE insult and then subjected to Western-blot and LC-MS/MS analysis. Subsequently, bioinformatic tools were used to analyze the data. The effect of SUMOylation on cytochrome P450 1A1 (CYP1A1) was evaluated by flow cytometry.
It was noted that CSE stimulated HBEs to undergo a SUMOylation turnover as evidenced by the changes of SUMOylated substrates and SUMOylation levels for a particular substrate. The SUMOylated proteins are relevant to the regulation of biological processes, molecular function and cellular components. Particularly, CSE stimulated a significant increase of SUMOylated CYP1A1, a critical enzyme involved in the induction of oxidative stress.
Our data provide a protein SUMOylation profile for better understanding of the mechanisms underlying COPD and support that smoking induces oxidative stress in HBEs, which may predispose to the development of COPD in clinical settings.
Solid-phase microextraction (SPME) has been demonstrated to be useful for
in vivo sampling in pharmacokinetic studies. In this study, a single time-point kinetic calibration for
in vivo dynamic ...monitoring was developed by simplification of the laborious multiple time-point kinetic calibration, based on the independent desorption kinetics of the preloaded standards from SPME fibers with the changing analyte concentrations. The theoretical foundation and practical application conditions, such as the replicate numbers, the optimal time-point for desorption, and the sampling time, were systematically investigated. Furthermore, the feasibility of using regular standards rather than deuterated ones for the kinetic calibration was justified by comparing to the data obtained using the deuterated standards. All the methods were verified by
in vitro and
in vivo experiments. The results from
in vivo SPME were validated by the blood drawing and chemical assay. These simplified calibration methods improved the quantitative applications of SPME for dynamic monitoring and
in vivo sampling, enhance the multiplexing capability and automatic potentials for high throughput analysis, and decrease expenses on reagents and instruments.
A method was developed for rapid qualitative determination of lignocellulose in the tobacco cell wall by utilizing 2D heteronuclear single quantum coherence NMR spectra (2D HSQC NMR). Traditional ...methods for analyzing the structure of lignocellulose involve many steps of separation and extraction, which is labor-intensive. In this work, the whole cell wall was milled and dissolved in deuterium solvent. The solvent dimethylsulfoxide (DMSO-d
) containing hexamethylphosphoramide (HMPA-d
) enhanced swelling of the sample and gave high-resolution spectra. The tobacco samples are ball milled at different ball milling times, and the state of the particles is observed through an electron microscope, and then the probability of the particles being less than 5 µm is counted. Through the comparison of the abundance and integration of the peak signals in the spectra under different transmittances, it was determined that when the milling time was 6 h, the quality of the NMR spectra was the best. The optimum conditions of characterizing tobacco structure were DMSO-d
/HMPA-d
solution and 6 h milling time. Under these conditions, complete representation of the structure of lignocellulose and simplified process could be achieved.
Neodymium ion imprinted polymer (Nd
3+-IIP) particles for selective solid-phase extraction of Nd
3+ were prepared and determined with inductively coupled plasma atomic emission spectrometry ...(ICP-AES). The unleached Nd
3+-IIP particles were prepared by the copolymerization of Nd
3+-5,7-dichloroquinoline-8-ol-4-vinylpyridine ternary complex with styrene and divinyl benzene, then Nd
3+ was leached to obtain Nd
3+-IIP particles. The adsorption capacity of the Nd
3+-IIP was 35.18 mg/g. The largest selectivity coefficient for Nd
3+ in the presence of competitive ions such as La
3+, Ce
3+, Pr
3+ and Sm
3+ was over 110. The proposed method was validated by analyzing two certified reference materials (GBW07301a sediment and GBW07401 soil) and the determined values were in a good agreement with standard values. The method was convenient, selective, sensitive and applicable to the determination of trace Nd
3+ in environmental samples with complicated matrix.
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