Novel adsorbents, magnetite nanoparticles modified with pectin shell and silica/pectin double shell, were fabricated and tested for single dye and dye mixture adsorption from water samples.

Pec/CS/JO formulated nanocomposite showed a 13-fold increase in potency against cancer cells, whereas cell viability of normal cells wasn't affected.

Efficient low carbon foot print methods are critical to achieving circularity for the dominant post-consumer plastic polyethylene terephthalate (PET). In a strong sustainability advancement over previous technologies, depolymerization of waste PET bottles was performed using a dissolution/degradation approach optimized in accordance with polymer mechanical parameter inter-relationships. A dual functioning deep eutectic solvent (DES), comprising m-cresol and choline chloride, served as both the solubilizing and catalyzing agent for alkaline hydrolysis of PET using high energy efficiency microwave (MW) irradiation. The PET depolymerization process was optimized using Box–Behnken design while tailoring the DES volume, concentration of the depolymerizing agent (sodium hydroxide), and MW irradiation time as independent variables. The percentage PET weight loss as high as 84% was obtained using 15 mL of DES containing 10% (w/v) NaOH under 90 s MW irradiation. Simple, cost-effective purification steps were afforded by the DES’s advantageous physicochemical nature and were implemented to provide the terephthalic acid (TPA) monomer with acceptable yield. Validation of the PET depolymerization and identification of obtained monomers were carried out by a range of characterization techniques including FTIR, NMR, DSC, and HPLC. Post-consumer PET bottle depolymerization was evaluated, and a 91.55% TPA monomer yield ready for repolymerization as virgin PET demonstrates the high potential market application of this low energy, low carbon solvent virgin to virgin approach to PET circularity.

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On a score sheet for plastics, bioplastics have a medium score for combined mechanical performance and a high score for biodegradability with respect to counterpart petroleum-based plastics. Analysis quickly confirms that endeavours to increase the mechanical performance score for bioplastics would be far more achievable than delivering adequate biodegradability for the recalcitrant plastics, while preserving their impressive mechanical performances. Key architectural features of both bioplastics and petroleum-based plastics, namely, molecular weight (Mw) and crystallinity, which underpin mechanical performance, typically have an inversely dependent relationship with biodegradability. In the case of bioplastics, both macro and micro strategies with dual positive correlation on mechanical and biodegradability performance, are available to address this dilemma. Regarding the macro approach, processing using selected fillers, plasticisers and compatibilisers have been shown to enhance both targeted mechanical properties and biodegradability within bioplastics. Whereas, regarding the micro approach, a whole host of bio and chemical synthetic routes are uniquely available, to produce improved bioplastics. In this review, the main characteristics of bioplastics in terms of mechanical and barrier performances, as well as biodegradability, have been assessed—identifying both macro and micro routes promoting favourable bioplastics’ production, processability and performance.

The efficiency of adsorption of two photosensitive fluoroquinolones; Ciprofloxacin (CIP) and Moxifloxacin (MOX), on the surface of synthesized magnetite/pectin nanoparticles (MPNPs) and magnetite/silica/pectin nanoparticles (MSPNPs) was studied from aqueous solution under varying experimental conditions. A validated spectrofluorimetric assay was developed for monitoring of CIP and MOX intact drugs and their photodegraded molecules concentrations. To optimize the working conditions which influence the drugs sorption, a 24 full factorial experimental design was implemented. The maximum percentage of removal was attained as 89% (type of sorbent = MSPNPs, pH = 7.0, initial drug concentration = 5 mg/L, and contact time = 30 min). The studied factorspH, NPs loading, initial drug concentration, and contact timewere significant for both types of sorbents. The most significant variable was pH, and the highest CIP and MOX adsorption occurred at pH = 7.0. Equilibrium isotherm data were fitted to Langmuir, Freundlich, and Sips equations, and the Sips model showed the best fit with equilibrium isotherm data. Furthermore, pseudo-first- and pseudo-second-order kinetic models were used to analyze sorption kinetics, and it was found that adsorption of the investigated fluoroquinolones followed pseudo-second-order kinetics. We believe that our synthesized NPs can be used as effective adsorbents for fluoroquinolones and their photodegraded molecules removal from aqueous solutions.

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An innovative antimicrobial technology for plastic surfaces is presented. We report the synthesis and scale-up of triangular silver nanoplates (TSNPs) and their integration into polycaprolactone (PCL) and polylactic acid (PLA) polymers through a solvent-casting technique. The TSNPs have a high geometric aspect ratio and strong local surface plasmon resonance (LSPR) response, which provides an effective tool for monitoring their integrity during processing and integration with the biodegradable plastics. An aqueous-based seed-mediated chemical method was used to synthesize the TSNPs, and characterisation was carried out using TEM and UV (Ultraviolet)-VIS (Visible) spectroscopy to measure LSPR profiles. The UV-VIS spectra of silver seeds and TSNPs exhibited characteristic peaks at 395 and 600 nm respectively. Synthesized TSNPs were coated with thiol-terminated polyethylene glycol (SH-PEG) and transferred into chloroform in order to effect compatibility with PCL and PLA. TSNP/PCL and TSNP/PLA composite films were prepared by solvent casting. The morphological structure, thermal, mechanical, and antimicrobial properties of the TSNP-incorporated composite films were evaluated. Results showed the TSNP-treated films had a rougher surface than the bare films. Insignificant changes in the thermal properties of TSNP-treated films compared to bare ones were also observed, which indicated the thermal stability of the composite films. The tensile strength and antimicrobial properties of the composite films were increased after TSNP incorporation. TSNP/PCL and TSNP/PLA films exhibited improved antimicrobial activity against Escherichia coli and Staphylococcus aureus with antimicrobial effect (AE) values ranging between 0.10 and 0.35. The obtained results and demonstrated TSNP production scalability validate the TSNP treated PCL and PLA films as a composite material with desirable antimicrobial effect for wide-ranging surface applications.