Alginate-modified surfactants functionalized metal-organic framework-based fluorescent film sensors for detection and adsorption of volatile aldehydes in water.

Volatile aldehydes have an adverse impact on both human health and the environment, therefore, a fast, straightforward, highly accurate detection technique for the simultaneous detection and removal of several aldehydes is eagerly anticipated. Herein, novel APGF@ZIF-8 and APOF@ZIF-8 sensing materials were developed by coating fluorescent alginate-modified surfactants (APGF and APOF) into the ZIF-8 MOFs to produce quite porous fluorescent sensors (SBET up to 1519 m2/g). The detection capacity of the prepared sensors for benzaldehyde, glyoxal, formaldehyde, and acetaldehyde has been examined. The detection mechanism was suggested as hydrogen bonding formation between the sensors and volatile aldehydes as confirmed by Gaussian calculations. All the fluorescence spectra of aldehydes display remarkable linear detection relationships in the range of 0.05-200 µM with the limits of detection (LOD) values in the range of 0.001-0.18 µM (0.106-10.44 ppb). These sensors were utilized successfully to detect multiple volatile aldehydes in river water samples with satisfactory recoveries of 96-107 %. Interestingly, fluorescent APGF@ZIF-8/CS and APOF@ZIF-8/CS films as portable disposable removal techniques for benzaldehyde, glyoxal, formaldehyde, and acetaldehyde from water were fabricated. APOF@ZIF-8/CS exhibited an excellent formaldehyde adsorption capacity of 58.30 mg/g and an adsorption removal efficiency of 93.5 %. The adsorption process of biosorbent on various aldehydes was fitted by Freundlich adsorption isotherm. The adsorption kinetics followed Pseudo-second-order kinetic model.

Enhancement of cytotoxic and antioxidant activities of Digenea simplex chloroform extract using the nanosuspension technique.

Digenea simplex (D. simplex), an Egyptian marine red macroalga, contains a diverse group of phytochemicals with unique bioactivities. At the same time, the synthesis of nanosuspension (NS) has received increasing interest to optimize the technological aspects of drugs. Thence, the main objective of this work was to use the chloroform extract (ChlE) of D. simplex to prepare its nanosuspension (ChlE-NS) formulation to increase its aqueous solubility, thereby improving its bioactivity. By using FTIR, GC/MS analysis, and phytochemical screening assays, the chemical profiling of ChlE was assessed. NS was prepared by the antisolvent precipitation technique using 1.5% w/v polyvinyl alcohol (PVA). A light microscope, FTIR, particle size distribution, polydispersity index (PDI), and zeta potential (ZP) measurements was used to characterize the prepared NS. Four cancer cell lines were used in the MTT experiment to investigate the anticancer potential of ChlE and ChlE-NS. An apoptotic mechanism was established using acridine orange/ethidium bromide (AO/EB) dual staining, DNA fragmentation, and increased caspase activity. ChlE and ChlE-NS were also evaluated as antioxidants using DPPH and ABTS free radical assays. The results showed that, when compared to ChlE, ChlE-NS had greater cytotoxic activity against the four cancer cell lines. However, results of antioxidant activity showed that ChlE-NS had an IC50 of 36.86 ± 0.09 and 63.5 ± 0.47%, while ChlE had values of 39.90 ± 0.08 and 86.5 ± 0.8% in DPPH and ABTS assays, respectively. Based on the results of this research, D. simplex ChlE-NS may be an effective strategy for enhancing ChlE's cytotoxic and antioxidant activities.

Cotton bandages finished with microcapsules of volatile organic constituents of marine macro-algae for wound healing.

Microencapsulation is an innovative technique having a growing application in textile finishing. Besides, marine macroalgae contain plenty of phytoconstituents used in various fields especially textile finishing. This work imparts the property of wound healing finish to cotton fabrics producing a bandage from eco-friendly algal volatile organic constituents (VOCs). VOCs extracted from Digenea simplex, Lurencea papillosa, Galaxurea oblongata, and Turbenaria decurrens Egyptian marine macroalgae scattered along the coastline of the Red sea were 0.52, 0.9, 0.87, and 0.62% (v/w), respectively. These VOCs as well as their microencapsulated (VOM) forms were finished onto cotton fabrics by a conventional pad-dry cure technique using sodium alginate (SA) as a shell wall material. The VOCs of each alga were extracted and chemically investigated using gas chromatography coupled with mass spectrometry (GC-MS). The results indicate, in addition to the identification of 125 volatile compounds, the diversity and outstanding differences in volatile composition among the 4 algae. Wound healing activities of the finished fabrics were evaluated. VOCs microcapsules-finished (VOMF) fabrics were more effective compared to VOCs-finished (VOF) fabrics and almost comparable to mebo-ointment (standard drug)-finished (MoF) fabrics. The differences in VOCs efficiencies may be attributable to the diversity in type and amount of volatiles found in the four algae. Therefore, this is a low-cost, convenient, reproducible, and scalable way to obtain encapsulated VOCs for the application in textile wound healing.

Preparation and characterization of smart therapeutic pH-sensitive wound dressing from red cabbage extract and chitosan hydrogel.

Developing a multifunctional wound dressing that protects, cures and indicates the healing progress, is a new approach of investigation. Red cabbage extract (RCE), consisting of bioactive compounds that have antioxidant, anti-inflammatory, anti-carcinogenic, bactericidal, antifungal, and antiviral activities, was utilized as a natural pH-sensitive indicator. Chitosan-based hydrogel, encapsulating RCE, was developed to obtain a smart therapeutic pH-sensitive wound dressing as antimicrobial bio-matrix provides a comfortable cushion for wound bed and indicates its status. Methacrylated-chitosan was crosslinked by different concentrations of methylenebisacrylamide (MBAA) by which hydrogel mechanical and morphological properties were tuned. The proposed mechanism for hydrogel formation was confirmed by FT-IR. The coloristic properties of the RCE and the changes in color intensity as a function of pH were confirmed by UV-Vis spectroscopy. The effect of MBAA on the mechanical, swelling, release and morphological properties of hydrogel were investigated. MBAA (2.5% wt/v) in 2% wt/v chitosan showed preferable mechanical (20 KPa), swelling (1294% at pH 8 ± 0.2), and release (prolonged up to 5 days) properties. Hydrogel matrices, loaded on cotton gauze submerged in different pH buffer solutions, showed explicit color changes from green to red as pH changed from 9 to 4.

Multifunctional Hydroxyapatite/Silver Nanoparticles/Cotton Gauze for Antimicrobial and Biomedical Applications.

Medical textiles have played an increasingly important protection role in the healthcare industry. This study was aimed at improving the conventional cotton gauze for achieving advanced biomedical specifications (coloration, UV-protection, anti-inflammation, and antimicrobial activities). These features were obtained by modifying the cotton gauze fabrics via in-situ precipitation of hydroxyapatite nanoparticles (HAp NP), followed by in-situ photosynthesis of silver (Ag) NPs with ginger oil as a green reductant with anti-inflammation properties. The HAp-Ag NPs coating provides good UV-protection properties. To further improve the HAp and Ag NPs dispersion and adhesion on the surface, the cotton gauze fabrics were modified by cationization with chitosan, or by partial carboxymethylation (anionic modification). The influence of the cationic and anionic modifications and HAp and Ag NPs deposition on the cotton gauze properties (coloration, UV-protection, antimicrobial activities, and water absorption) was thoroughly assessed. Overall, the results indicate that chemical (anionic and cationic) modification of the cotton gauze enhances HAp and Ag NPs deposition. Chitosan can increase biocompatibility and promotes wound healing properties of cotton gauze. Ag NP deposition onto cotton gauze fabrics brought high antimicrobial activities against Candida albicans, Gram-positive and Gram-negative bacteria, and improved UV protection.

Synthesis and characterization of hydrolysed starch-g-poly(methacrylic acid) composite.

A novel method for the synthesis of starch-g-poly(methacrylic acid) composite was adopted by graft polymerization of hydrolysed starch (HS) and methacrylic acid (MAA) in aqueous medium using an efficient sodium perborate (SPB)-thiourea (TU) redox initiation system. The parameters influencing the redox system efficiency and thence the polymerization method were considered. These parameters comprehended the concentrations of MAA, SPB, TU and SPB/TU molar ratio as well as the polymerization temperature. The polymerization reaction was scrutinized through calculation of the MAA total conversion percent (TC%). The resultant poly(MAA-HS) composite was assessed by evaluating the polymer criteria (the graft yield, GY%; the grafting efficiency, GE%; the homopolymer, HP%; and the total conversion). The comportment of the apparent viscosity of the cooked poly(MAA)-starch composite paste, obtained under diverse polymerization conditions, was examined. Tentative mechanisms, which depict all occasions that happen amid the entire course of the polymerization reaction, have been proffered.