In recent years, natural polymers have replaced synthetic polymers for antibacterial orthopedic applications owing to their excellent biocompatibility and biodegradability. Zein is a biopolymer found in corn. The lacking mechanical stability of zein is overcome by incorporating bioceramics, e.g., mesoporous bioactive glass nanoparticles (MBGNs). In the present study, pure zein and zein/Zn–Mn MBGN composite coatings were deposited via electrophoretic deposition (EPD) on 316L stainless steel (SS). Zn and Mn were co-doped in MBGNs in order to make use of their antibacterial and osteogenic potential, respectively. A Taguchi design of experiment (DoE) study was established to evaluate the effect of various working parameters on the morphology of the coatings. It was observed that coatings deposited at 20 V for 5 min with 4 g/L concentration (conc.) of Zn–Mn MBGNs showed the highest deposition yield. Uniform coatings with highly dispersed MBGNs were obtained adopting these optimized parameters. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were employed to investigate the morphology and elemental composition of zein/Zn–Mn MBGN composite coatings. Surface properties, i.e., coating roughness and wettability analysis, concluded that composite coatings were appropriate for cell attachment and proliferation. For adhesion strength, various techniques, including a tape test, bend test, pencil hardness test, and tensile test, were performed. Wear and corrosion analysis highlighted the mechanical and chemical stability of the coatings. The colony forming unit (CFU) test showed that the zein/Zn–Mn MBGN composite coating was highly effective against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) due to the presence of Zn. The formation of a hydroxyapatite (HA)-like structure upon immersion in the simulated body fluid (SBF) validated the in vitro bioactivity of the coating. Moreover, a WST-8 assay depicted that the MG-63 cells proliferate on the composite coating. It was concluded that the zein/Zn–Mn MBGN coating synthesized in this work can be used for bioactive and antibacterial orthopedic applications.
Lead-free ceramics are promising candidates for replacing lead-based piezoelectric materials such as lead-zirconate-titanate (PZT) if they can compete in dielectric and ferroelectric characteristics. In this work, for lead-free piezoelectric ceramic, 0.74(Bi0.5Na0.5TiO3)-0.26(SrTiO3) (BNT-ST26) and niobium-substituted (Nb-BNT–ST26) ceramics were synthesized by solid-state reactions. The evolution of niobium substitution to the perovskite phase structure of BNT-ST26 ceramics was confirmed by X-ray diffraction (XRD) analysis and Raman spectra. Electromechanical properties of Nb-BNT-ST26 ceramics initially increased with the addition of niobium up to 0.5% and decreased with a further increase in Nb content. Temperature-dependent dielectric curves showed that the depolarization temperature (Td) decreased below room temperature because of Nb substitution. The composition with 0.5% Nb yielded a maximum bipolar strain (Smax) of 0.265% and normalized strain of d33* ~ 576 pm/V under an electric field of 4.6 kV/mm at room temperature. At this critical concentration of 0.5% Nb, maximum saturation polarization of 26 μC/cm2 was achieved. The dielectric constant with temperature peaks became more diffused and the depolarization temperature decreased with the increasing Nb content. The study concludes that Nb-doped BNT-ST26 is an excellent material for high-temperature, stable, frequency-dependent, lead-free piezoelectric devices.
In recent years, natural polymers have replaced synthetic polymers for antibacterial orthopedic applications owing to their excellent biocompatibility and biodegradability. Zein is a biopolymer found in corn. The lacking mechanical stability of zein is overcome by incorporating bioceramics e.g. mesoporous bioactive glass nanoparticles (MBGNs). In present study, pure zein and zein/Zn-Mn MBGNs composite coatings were deposited via electrophoretic deposition (EPD) on 316L stainless steel (SS). Zn and Mn were co-doped in MBGNs in order to make use of their antibacterial and osteogenic potential, respectively. A Taguchi design of experiment (DoE) study was established to evaluate the effect of various working parameters on the morphology of the coatings. It was observed that coatings deposited at 20 V for 5 min with 4 g/L concentration (conc.) of Zn-Mn MBGNs showed highest deposition yield. Uniform coatings with highly dispersed MBGNs were obtained adopting these optimized parameters. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-Ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR) were employed to investigate the morphology and elemental composition of zein/Zn-Mn MBGNs composite coating. Surface properties i.e. coating roughness and wettability analysis concluded that composite coatings were appropriate for cell attachment and proliferation. For adhesion strength various techniques including tape test, bend test, pencil hardness test, and tensile test were performed. Wear and corrosion analysis highlighted the mechanical and chemical stability of coatings. Colony forming unit (CFU) test showed that zein/Zn-Mn MBGNs composite coating was highly effective against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) due to the presence of Zn. The formation of hydroxyapatite (HA) like structure upon immersion in simulated body fluid (SBF) validated the in vitro bioactivity of the coating. It was concluded that zein/Zn-Mn MBGNs coating synthesized in this work can be used for bioactive and antibacterial orthopedic applications.
The presence of chemicals, heavy metals, and colorants from textile effluents in water represent a significant health risk. To address this, a range of treatment methods, including ion exchange, membrane processes, physicochemical approaches, and biological techniques, are employed to eliminate these contaminants. Activated carbon, distinguished by its porous structure and effective pollutant, is a notable solution. An environmentally sustainable method involves producing activated carbon from agricultural and industrial waste to combat water pollution. For instance, the recycling of industrial waste, like glass fiber-reinforced plastic, can be used for water treatment via pyrolysis with a ZnCl2 activation process. The quality of the activated carbon is confirmed through characterization methods such as XRD, FTIR, SEM, and Raman spectroscopy, suggesting potential applications extending beyond water filtration, encompassing supercapacitors, fuel storage, and CO2 absorption. This study underscores the environmentally friendly potential of repurposing industrial waste for efficient and eco-conscious water purification.