•Renewable/natural ingredients based edible films and coatings.•Polysaccharides based coatings versatile in functioning, furnish a green approach.•Edible coatings functions as carrier for ...aroma/flavoring agents without any impact on natural constituents of products.•Future prospects with new research directions.
Food is a vital product for the survival of human beings and with passage of time quality concerns of consumers are rising. Edible films and coatings are thin layers applied on food products to protect them and improve their quality. Films/coatings are prepared from naturally occurring renewable sources (polysaccharides, proteins, lipids and composites) which we can eat without disposing them. These films are environment friendly and contain antioxidants, anti-browning agents and colorants. Various methods (spraying, brushing, electro-spraying) are used to apply a coating on food material to protect them from microbial growth, prolonging their shelf life and improving other quality aspects like sensory attributes, appearance, originality and freshness of ingredients. In addition to edible films, some special additives like glycerol, sorbitol etc. is used to improve the efficiency of edible films and coatings. Chemistry and nature of these films and coatings vary in the vast range of hydrophilic and hydrophobic boundaries to cover the whole range of food products. In recent times, herbal coatings are widely used for the coating purposes e.g. Aloe Vera, citral and eugenol essential oils. However, some challenges presented are focusing the scientific attention for viable solution.
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•The membrane was prepared by using a novel nature-inspired method.•The membrane possesses self-cleaning and antibacterial properties.•The membrane exhibits robust mechanical strength ...and stability.•The membrane features excellent biocompatible and UV-shielding.•Using this membrane can effectively separate various oil-water mixtures.
Fabrication of environmental-friendly, low-cost, and free-standing superhydrophobic nanofibrous membranes with additional functionalities such as self-cleaning and UV-shielding properties is highly demanded for oil-water separation. Herein, we describe the preparation of multifunctional superhydrophobic nanofibrous membrane by using a facile and novel nature-inspired method, i.e., plant polyphenol (tannic acid) metal complex is introduced to generate rough hierarchical structures on the surface of an electrospun polyimide (PI) nanofibrous membrane, followed by modification of poly (dimethylsiloxane) (PDMS). Taking an as-prepared tannic acid − Al3+-based superhydrophobic membrane as an example, it not only exhibits anti-impact, low-adhesive and self-cleaning functions, but also presents excellent performance in the separation of various oil-water mixtures. A high flux up to 6935 l m−2 h−1 with a separation efficiency of over 99% and the oil contents in water below 5 ppm is obtained even after repeating use for twenty separation cycles. Additionally, the membrane exhibits excellent UV-shielding property, attributing to the inherent UV-absorbing ability of tannic acid. Furthermore, the membrane also possesses additional properties including antibacterial activity, good biocompatibility, robust mechanical strength, and excellent resistance to various harsh conditions. These attractive properties of the as-prepared membrane make it a promising candidate for potential applications in industrial oil-contaminated water treatments and oil-water separation.
This study aims to improve properties of Ultem
polyetherimide (PEI) by incorporating up to 2 wt% additives of the perovskite oxide La
Yb
AlO
(LYA). The structure of dense PEI/LYA films was ...characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) in combination with an analysis of their elemental composition using energy-dispersive spectroscopy (EDS). The PEI/LYA films exhibit a two-layer structure. Contact angle measurements revealed hydrophilization of the membrane surface enriched with the perovskite. The transport properties were tested via gas separation and pervaporation processes. The separation selectivity of He/N
and O
/N
gas pairs increased with the growth of the LYA content in the membranes. Pervaporation of a methanol(MeOH)-cyclohexane(CH) mixture was effective due to the high sorption of MeOH in the PEI/LYA membranes. The maximal pervaporation separation index was found for the PEI/LYA(2%) membrane.
Lateral flow assays Koczula, Katarzyna M; Gallotta, Andrea
Essays in biochemistry,
06/2016, Letnik:
60, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Lateral flow assays (LFAs) are the technology behind low-cost, simple, rapid and portable detection devices popular in biomedicine, agriculture, food and environmental sciences. This review presents ...an overview of the principle of the method and the critical components of the assay, focusing on lateral flow immunoassays. This type of assay has recently attracted considerable interest because of its potential to provide instantaneous diagnosis directly to patients. The range and interpretation of results and parameters used for evaluation of the assay will also be discussed. The main advantages and disadvantages of LFAs will be summarized and relevant future improvements to testing devices and strategies will be proposed. Finally, the major recent advances and future diagnostic applications in the LFA field will be explored.
•Recent advances in artificial intelligence for predicting fouling are presented.•Working principles of AI technologies for membrane fouling prediction are discussed.•Comparisons of the inputs, ...outputs, and accuracy of AI approaches are conducted.•Future research efforts are highlighted for AI technologies in predicting membrane fouling.
Membrane fouling is one of major obstacles in the application of membrane technologies. Accurately predicting or simulating membrane fouling behaviours is of great significance to elucidate the fouling mechanisms and develop effective measures to control fouling. Although mechanistic/mathematical models have been widely used for predicting membrane fouling, they still suffer from low accuracy and poor sensitivity. To overcome the limitations of conventional mathematical models, artificial intelligence (AI)-based techniques have been proposed as powerful approaches to predict membrane filtration performance and fouling behaviour. This work aims to present a state-of-the-art review on the advances in AI algorithms (e.g., artificial neural networks, fuzzy logic, genetic programming, support vector machines and search algorithms) for prediction of membrane fouling. The working principles of different AI techniques and their applications for prediction of membrane fouling in different membrane-based processes are discussed in detail. Furthermore, comparisons of the inputs, outputs, and accuracy of different AI approaches for membrane fouling prediction have been conducted based on the literature database. Future research efforts are further highlighted for AI-based techniques aiming for a more accurate prediction of membrane fouling and the optimization of the operation in membrane-based processes.
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Octafluorocyclopentene (OFCP) engages linear, unprotected peptides in polysubstitution cascades that generate complex fluorinated polycycles. The reactions occur in a single flask at 0–25 °C and ...require no catalysts or heavy metals. OFCP can directly polycyclize linear sequences using native functionality, or fluorospiroheterocyclic intermediates can be intercepted with exogenous nucleophiles. The latter tactic generates molecular hybrids composed of peptides, sugars, lipids, and heterocyclic components. The platform can create stereoisomers of both single- and double-looped macrocycles. Calculations indicate that the latter can mimic diverse protein surface loops. Subsets of the molecules have low energy conformers that shield the polar surface area through intramolecular hydrogen bonding. A significant fraction of OFCP-derived macrocycles tested show moderate to high passive permeability in parallel artificial membrane permeability assays.
Electrodialysis self-reversal (EDR) technology has attracted in the treatment of water for domestic and industrial uses. The self-reversal consists of a frequent reversal of the direction of current ...between the EDR-cell electrodes to combat fouling of ion exchange membranes (IEMs). Irrespective of the EDR self-cleaning processes, the role of natural organic matter and their complexing ability with metal ions on IEMs fouling is partially understood. The objective of this review is to identify the research gaps present in the elucidation of IEM fouling routes. The common IEMs’ foulants are identified, and several fouling mechanisms are briefly discussed. The effectiveness of self-cleaning mechanisms to reduce IEMs fouling is also be discussed. Dissolved organic carbon (DOC) possesses high chelation which forms metal complexes with di and trivalent cations found in water. The role of ternary complexes, e.g. M2+/3+–DOC and membrane surface, on membrane fouling via surface bridging, are also addressed. Finally, mitigation methods of IEMs membrane fouling are also discussed.
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•Self–reversal in EDR fails some times to get rid of foulants.•Groundwater contains DOC–Ca2+ complexes alone with free Ca2+ ions.•Ternary DOC–Ca2+ –membrane complexes responsible for irreversible fouling in AEMs.
With the rising demand for fresh and ready-to-eat foods, antimicrobial packaging has been developed to control or prevent microbial growth as well as maintain food quality and safety. Chitosan is an ...advanced biomaterial for antimicrobial packaging to meet the growing needs of safe and biodegradable packaging. The application of natural essential oils as antimicrobial agents effectively controls the growth of spoilage and pathogenic microbes. Thus, chitosan edible coatings and films incorporated with essential oils have expanded the general applications of antimicrobial packaging in food products. This review summarized the effect of essential oils on modifying the physicochemical characteristics of chitosan-based films. Notably, the antimicrobial efficacy of the developed composite films or coatings was highlighted. The advances in the preparation methods and application of chitosan films were also discussed. Broadly, this review will promote the potential applications of chitosan-essential oils composite films or coatings in antimicrobial packaging for food preservation.
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•This review presented advances in chitosan films containing essential oils (EOs).•Various methods for the preparation of chitosan films were discussed.•EOs can modify the physical and mechanical properties of chitosan films.•Chitosan films incorporated with EOs exhibited enhanced antimicrobial activity.•These films or coatings have potential applications in extending food shelf-life.
•AGS-MBR greatly lowered fouling rate in comparison with that of the conventional MBR.•A new scouring model was developed to explain the AGS scouring mechanism.•The AGS scouring stress is ...proportional to the total amount of AGS on the membrane.•A contribution quantification model was built to evaluate fouling mitigation factors.•AGS scouring had a contribution rate of 39.97% for membrane fouling mitigation.
Aerobic granular sludge (AGS) has been proven to have a low fouling potential in membrane bioreactor (MBR). Nevertheless, AGS scouring effect on mitigating membrane fouling remains poorly investigated. The main objective of this study is to examine AGS-MBR performance, to reveal the AGS scouring mechanism and quantify its contribution rate to membrane fouling mitigation, from the views of theory and experiment. Above all, AGS-MBR exhibited a low fouling rate ((transmembrane pressure (TMP) kept below 20 kPa) without membrane cleaning and a higher removal of organics and nutrients than conventional MBR during 80 days’ sludge granulation process. Then, flocculent sludge (FS) with various AGS ratios was applied to simulate the sludge granulation phase. When AGS ratio increased from 0% to 100%, the permeate flux gradually elevated from 40.0 L m−2h−1 to 92.9 L m−2h−1, and fouling resistance decreased from 9.0 × 10−12m−1 to 3.9 × 10−12m−1 benefiting from the loose structure and high porosity of AGS fouling layer. Meanwhile, the scouring effect produced by AGS on the membrane fouling mitigation was investigated. Based on the momentum conservation, a new hydrodynamic model was developed to explain the scouring mechanism of AGS. The scouring stress, proportional to the total amount of AGS depositing on the membrane surface, effectively reinforced the collision between AGS and FS, and reduced their deposition on the membrane surface by friction with the membrane; thus it was further conducive to membrane fouling mitigation. Moreover, a novel contribution quantification model was proposed for analyzing the contribution rate of AGS scouring effect to mitigate membrane fouling. AGS scouring possessed a significant contribution rate (39.9%) for fouling mitigation, compared with AGS structure (50.3%) and hydraulic stress (9.7%). In final, this study provides an in-depth understanding to mitigate the MBR membrane fouling by the unique advantages of sludge granulation.
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•A new concept of SIP was proposed for the preparation of PEA NF membranes.•The reactivity of hydramine could be activated by a trace amount of diamine.•The “hydramine-diamine” coupling unit acts as ...the reactive monomer.•The PEA membranes exhibited an improved salt rejection and considerable PWP.
Polyester-amide (PEA) thin film composite (TFC) NF membranes have rapidly evolved towards a competitive performance, benefiting from their remarkable antifouling capability and superior chlorine resistance. In this report, a new concept of synergistic interfacial polymerization is explored, which promptly triggers the reaction between hydramines and trimesoyl chloride (TMC) in the presence of a trace amount of diamines. This rapid-start mode enables the formation of defect-free PEA films without the requirement of catalysis. A comprehensive characterization of physicochemical properties using high-resolution mass spectrometer (HRMS) reveals that the recombination and formation of a “hydramine-diamine” coupling unit plays a decisive role in activating the synergistic interfacial polymerization reaction with TMC molecules. Taking the pair of serinol and piperazine (PIP) as an example, the PEA-NF membrane fabricated with 0.1 w/v% serinol mixed with 0.04 w/v% PIP as water-soluble monomer and 0.1 w/v% TMC as oil phase monomer was found to have a pure water permeability (PWP) of 18.5 L·m−2·h−1·bar−1 and a MgSO4 rejection of 95.5 %, which surpasses almost all the reported PEA NF membranes. Findings of the current research provide more possibilities for the low-cost and rapid synthesis of high-performance PEA membranes aiming for water purification.
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