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•Chitosan Schiff bases bearing salicylidene ionic liquids were prepared and characterized.•Metalation of these Schiff bases afford the corresponding Ag(I)/Pd(II) complexes ...(M-ILCSBs).•The new compounds were evaluated for their in vitro antimicrobial and antitumor efficacy.•ILCSBs and M-ILCSBs are more effective than chitosan as antimicrobial agents.•M-ILCSBs were found to be more cytotoxic than ILCSBs.
In our endeavor to develop a new class of pharmacological candidates with antimicrobial and anticancer efficacy, a series of biopolymeric chitosan Schiff bases bearing salicylidene ionic liquid (IL-Sal) brushes (ILCSB1-3, poly-(GlcNHAc-GlcNH2-(GlcN-Sal-IL)) was successfully synthesized by adopting efficient synthetic routes. Unfortunately, metalation trials of these biopolymeric Schiff bases afford the corresponding Ag(I)/M(II) complexes (where M=Co, Pd). These designed architectures were structurally characterized and pharmacologically evaluated for their in vitro antimicrobial, against common bacterial and fungal pathogens, and anticancer activities against human colon carcinoma (HCT-116) cell line. In conclusion functionalization of chitosan with IL-Sal brushes coupled with metalation of formed ILCSBs were synergistically enhanced its antimicrobial and antitumor properties to a great extent. Noteworthy, Ag-ILCSB2 (IC50=9.13μg/mL) was ca. 5-fold more cytotoxic against HCT-116 cell line than ILCSB2 (IC50=43.30μg/mL).
•O. syriacum essential oil (OSEO) and imidazolium-Zn(II)Salen were prepared and characterized.•OSEO and Zn(II)Salen were separately or co-encapsulated by chitosan nanoparticles (CSNPs).•Spectral, ...microscopic, and thermal analyses confirmed the successful encapsulation.•Zn(II)Salen-/ OSEO-loaded CSNPs displayed good in-vitro release profiles.•Nanoencapsulation with CSNPs improved the antimicrobial potencies of Zn(II)Salen and OSEO.
This study reports preparation and physicochemical characterization of natural antimicrobials (Origanum Syriacum essential oil (OSEO), shrimp chitosan nanoparticles (CSNPs)) and new imidazolium ionic liquid-supported Zn(II)Salen. These antimicrobials were separately or co-encapsulated by CSNPs to fabricate novel antimicrobial nanoplatforms "NPFs" (OSEO-loaded CSNPs (NPF-1), Zn(II)Salen-loaded CSNPs (NPF-2), and Zn(II)Salen@OSEO-loaded CSNPs (NPF-3)). The finding of loading, encapsulation, and antimicrobial release studies confirm the suitability of CSNPs for nanoencapsulation of Zn(II)Salen and OSEO. All NPFs can significantly suppress the growth of microbial species with performances dependent upon the microbial strain and nanoplatform concentration. The susceptibility of microbes toward new antimicrobials was as follows; Gram-positive bacteria > Gram-negative bacteria > fungi. The amazing physicochemical features of new nanoplatforms and their bioactive ingredients (Zn(II)Salen, OSEO, and CSNPs) signify the importance of our designs for developing a new generation of nanopharmaceuticals supported both natural products and biogenic ionic metal cofactors, targeting the multidrug resistant (MDR) pathogens.
The toxicity of cisplatin (CDDP) toward the renal tubules and its severe effects on the proximal tubules limits its further use in cancer therapy. The current study was undertaken to evaluate the ...protective effects of gallic acid-grafted O-carboxymethyl chitosan (GA@CMCS) against nephrotoxicity induced by CDDP in rats. Renal injury was assessed in the GA@CMCS/CDDP-treated rats using kidney injury molecule-1 (KIM-1). Moreover, the levels of reduced glutathione (GSH), malondialdehyde (MDA), and nitric oxide (NO) were measured. The comet assay was performed to measure the DNA damage. The renoprotective activity of GA@CMCS was supported by histo- and immuno-pathological studies of the kidney. GA@CMCS significantly normalized the increases in kidney homogenate of KIM-1, MDA, and NO-induced by CDDP and significantly increased GSH as compared with the CDDP group. GA@CMCS also significantly protects rat kidneys from CDDP-induced histo- and immuno-pathological changes. Both biochemical findings and histo- and immuno-pathological evidence showed the renoprotective potential of GA@CMCS against CDDP-induced oxidative stress, inflammation, and renal dysfunction in rats. In conclusion, GA@CMCS has been shown to mitigate the nephrotoxicity impact of CDDP in cancer therapy.
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•Synthetic routes of poly-(imidazolium vanillyl) chitosan Schiff bases (PIVCSBs) are reported.•Two protocols have addressed for preparation of AgNPs, green and chemical.•AgNPs-based ...NBCs have been fabricated via capping of AgNPs with PIVCSBs.•Applying of NBCs to cotton fabrics acquired them potent antimicrobial efficacies.•Treated cotton fabrics have strong bactericidal activity.
Current work offers two simple synthetic routes for the production of poly-(imidazolium vanillyl)-grafted oligochitosan Schiff bases (PIVCSBs) and their silver nano-biocomposites (NBCs). First, a green in-situ protocol for preparation of silver nanoparticles (AgNPs) using PIVCSBs as a synergetic reductant and capping agent to afford PIVCSBs/Agin NBCs. Contrariwise, in the ex-situ protocol the AgNPs were initially fabricated and then capped by PIVCSBs to fabricate PIVCSBs/Agex NBCs. Structural, morphological and physicochemical features of new architectures were examined by diverse techniques. The obtained NBCs were applied as cotton fabrics antibacterial finishing additives via a pad-dry-curing method. The obtained data revealed that the AgNPs produced by in-situ approach are spherical, smaller size, well-stabilized, and uniformly distrusted when compared with that formed using ex-situ technique as proved by UV–Vis, SEM micrographs and TEM techniques. Moreover, the antibacterial properties of cotton-treated fabrics were evaluated against E. coli and S. aureus species and acquired very strong bactericidal activity to cotton fabrics.
Cross-linked quaternized polyethersulfone (QPES) hybrid mixed polymer membranes (MPMs) loading amino crystalline nanocellulose (ACNC) were successfully fabricated and applied for phosphate removal. ...The successful production of novel materials was validated by microscopic, spectral, and microanalytical methods. When compared to the native QPES membrane, the primary qualities of QPES hybrid membranes (hydrophilicity, porosity, permeability, antifouling) have been greatly improved overall. In addition, the surface zeta potential (SZP) and ion exchange capacity (IEC) measurements demonstrated the high positive surface charge densities of MPMs, which is beneficial for phosphate uptake. Phosphate adsorption by these membranes was studied at different temperatures, contact times, and initial phosphate concentrations using batch experiments, to investigate the optimal conditions for phosphate uptake. The MPMs showed excellent adsorption capacities with maximal removal capacities in the range of 68.8–87.95 %. Phosphate adsorption on MPMs was regulated primarily by the Sips isotherm model with multilayer adsorption capabilities and exhibited pseudo-second order kinetics (R2 = 0.9951–0.9976). The positive ΔH° and ΔS° values are indicative of the endothermic nature of phosphate adsorption and randomness increase. The negative ΔG° value indicates the spontaneousity of phosphate adsorption. Phosphate removal effectiveness of the membranes was maintained following recovery and regeneration with NaOH.
A green and sustainable heterogeneous nanocatalyst for the Suzuki reaction was fabricated by refining rice straw to ionic nanocellulose Schiff base (NCESB) which was employed for bio-reduction of ...Pd(II) into Pd nanoparticles (Pd NPs) and immobilization of these NPs to fabricate the desired nanocatalyst (NCESB@Pd). The TEM image revealed well-dispersed PdNPs with sizes of 5–23 nm. The new nanocatalyst displayed amazing activity in catalyzing coupling reactions of a wide range of halobenzenes with phenylboronic acid at 50 °C (reaction time 15–60 min) and even at room temperature (reaction time 120 min). The NCESB@Pd nanocatalyst exhibited excellent recyclability (up to five catalytic runs) without a significant loss of its activity or identity. Therefore, the new ionic nanocatalyst may open a new window for a novel generation of ionic low-cost green and highly effective nanocatalysts for organic transformation reactions.
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•Rice straw was successfully refined to ionic nanocellulose Schiff base (NCESB).•NCESB was used as bio-reductant of Pd(II) and support for fabrication of NCESB@Pd nanocatalyst.•The nanocatalyst displayed amazing activity in catalyzing Suzuki coupling reactions.•NCESB@Pd exhibits excellent recyclability (up to five catalytic runs).
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•Ammonium-salicylidene chitosan Schiff base (ASCSB) was prepared and characterized.•New ternary nanocomposites based on ASCSB, TiO2, and ZnO nanoparticles were in-situ fabricated.•New ...ternary nanocomposites (NC1,2) were applied for treating cotton fabrics.•The treated cotton fibers demonstrated excellent antimicrobial impacts on different pathogens.•The ZnO-rich nanocomposite endowed fabrics with more UV protection than TiO2-rich one.
The purpose of this work is to offer a novel approach to designing multifunctional technical cotton textiles by coating them with smart bio-materials. Two different ternary nanocomposites (NC1, NC2) comprising (ammonium-salicylidene) chitosan Schiff base (ASCSB), TiO2, and ZnO nanoparticles were in-situ prepared and applied for treating cotton fibers using the facile pad-dry-cure process to impart antimicrobial and ultraviolet protection characteristics. Notably, NC1 is TiO2-rich, while NC2 is rich in ZnO. The physicochemical and visual characteristics of the new nanocomposites and the treated fabrics were investigated by spectral, microscopic, and thermal methods. The as-prepared NC1 exhibited a more homogeneous distribution, higher depositing density and smaller mean nanoparticle size (48 nm) when compared to NC2 (56 nm). In contrast, NC2-treated fabrics showed a higher depositing density of nanoparticles than NC1-treated ones. The treated cotton fibers demonstrated strong and sustainable antimicrobial impacts on S. aureus, E. coli, and C. albicans pathogens, with more effective performance for NC2-treated textiles in comparison to NC1-treated fabrics. The NC2-remediated cotton fabrics demonstrated a higher UV protection factor (UPF) value (53) as compared to NC1-coated fabrics (35), indicating that the ZnO-rich nanocomposite endowed cotton fabrics with more ultraviolet protection than TiO2-rich nanocomposite.
Imidazolium salts (Im+–R2R3–Cl−) attached to the N,N′-bis(salicylidene)-(±)-trans-1,2-diaminocyclohexane (saldach) backbone (4a–f) have been designed and successfully applied for the synthesis of the ...corresponding mononuclear complexes with Mn(III) and Fe(III) ions. The molecular structures of the saldach ligands H2(R1)2saldach(Im+–R2R3–Cl−)2 (R1 = H, tert-Bu, R2 = H, Et, n-Bu, R3 = H, Me) and their M(III)Cl{(R1)2saldach(Im+–R2R3–Cl−)2} (M = Mn, Fe) complexes have been established. The free ligands exist as the phenol-OH and not as the zwitterionic (imine)N–H+···−O(phenol) tautomer. Antimicrobial activity of the target compounds revealed higher potent antibacterial activity against Salmonella aureus, B. subtilis while less effective against E. coli and C. albicans and inactivity against A. flavus. Compound (4d) and its Fe(III) complex (6d) exhibit remarkable extra-potent bactericidal activity.
Display omitted A novel synthetic strategy has been successfully developed for the synthesis of saldach–imidazolium derivatives and their complexes. These compounds represent promising candidates when set in the context of antimicrobial applications.
•N,N′-Bis(salicylidene)-(±)-trans-1,2-diaminocyclohexane (saldach) as scaffold.•Imidazolium salts (Im+–R2R3–Cl−) covalently attached to H2(R1)2 saldach backbone.•Compounds were tested against four bacterial pathogens and two fungal strains.•Most compounds showed promising antibacterial activity.•H2(tBu)2saldach(Im+–HMe–Cl−)2 and its Fe-complex are possible antibiotic candidates.
Capacitive deionization (CDI) is being progressed as an auspicious ion removal technique from brackish and seawater. Herein, we introduce a novel one-step facile chemical approach to fabricate ...tubular architectured composite electrodes made of both Titania and Multiwalled carbon nanotubes (TNTs/MWCNTs). The composites have been exploited, for the first time, as electrode materials for capacitive deionization. The composite electrodes were fully characterized
via
Field Emission Scanning Electron Microscopy (FESEM), Raman spectroscopy, X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) techniques, and Nitrogen Sorption. The electrochemical response was investigated by using Cyclic Voltammetry (CV), Galvanostatic Charge and Discharge (GCD), and Potentio-Electrochemical Impedance Spectroscopy (PEIS) measurements. The fabricated composite electrodes containing 5 wt% TiO
2
nanotubes showed remarkable specific capacitance, conductivity, reversibility, and durability compared to pristine MWCNTs and other MWCNT-based composite electrodes reported in the literature. The desalination capability of the composite electrode was investigated using batch mode operation. The electrosorption capacity of the composite electrode containing 5 wt% TiO
2
nanotubes (13.2 mg g
−1
) is approximately two fold larger than that of pristine MWCNTs (7.7 mg g
−1
), indicating an improved desalination efficiency. Therefore, the fabricated TNT/MWCNT composite electrode is a promising candidate for CDI technology.
TiO
2
/CNT composites are energy-efficient capacitive deionization platforms with exceptional electrosorption capacity.
A new simple pH-sensitive fluorescent probe, methylimidazolium salicylaldehyde ionic liquid (MeIm-Sal-IL), was designed and successfully synthesized from commercially available salicylaldehyde (Sal)
...via
an extremely simple efficient two-step synthetic protocol. This new pH sensor has prominent advantages over traditional fluorescent pH probes, such as a large Stokes shift (∼125 nm) and extreme aqueous solubility along with simultaneous color and fluorescence profile changes as a result of pH alteration. The fluorescence behavior of this new probe provides a new state-of-the-art pH sensing method. Fluorescence turn-on is observed with increasing pH ( 5 to 11), accompanied by a bathochromic shift of 70 nm from (
λ
max
emission 435 to 505 nm;
λ
max
absorption 323 to 378 nm). This bathochromic shift may be ascribed to the tautomeric equilibrium involving excited-state intramolecular proton transfer (ESIPT). Meanwhile, the fluorescence intensity enhancement at higher pH is attributable to the internal charge transfer (ICT) process. Also, the new probe was labeled with silica nanoparticles (SiNPs) in order to produce a novel nano-fluorosensor for pH measurements. The nanosensor was fabricated by covalent labeling of chloro-modified SiNPs with the new probe. The emission spectra of the new nanosensors are bathochromically shifted by about 65 nm (
λ
max
emission 435 to 500 nm) at low pH (3 to 5). Moreover, the fluorescence intensity of the nanosensor is increased by 60 fold in the pH range from 5 to 9. The sensitivity of the new nanosensor is highly applicable within the pH range of 5 to 9, which suggests a broad variety of applications in the physiological pH range.
A turn-on pH nano-fluorosensor based on a new probe labeled SiNPs was designed. The new probe is based on ESIPT process for Sal bearing 2-MeIm ionic liquid terminal. The pH sensing performance of the nanosensor has been investigated.
