New cellulose carbamates and cellulose acetate carbamates were prepared by classical addition reaction of isocyanates with alcohols. A Telomerization technique was used to make the grafted molecules ...strongly anchored and more hydrophobic. These molecules were grafted into cellulose and CA chains, respectively. The structures of the synthesized derivatives were confirmed using Nuclear Magnetic Resonance Spectroscopy, Fourier Transform Infrared and Thermogravimetric Analysis, and their solubility phenomenon was also established, and the carbamate derivatives showed better solubility compared to cellulose. Their ability to biodegrade was investigated, and it was concluded that Cell-P
and CA-P
derivatives are more biodegradable than the other samples. These results suggest that the resulting compounds can be used effectively in many useful industrial fields, for instance, eco-friendly food packaging, domains that use materials that are environmentally friendly and sustainable and the development of green chemistry.
In this study, tin dioxide nanoparticles (SnO
NPs) were successfully synthesized through an eco-friendly method using basil leaves extract. The fabricated SnO
NPs demonstrated significant adsorption ...capabilities for phenol (PHE), p-nitrophenol (P-NP), and p-methoxyphenol (P-MP) from water matrices. Optimal conditions for maximum removal efficiency was determined for each phenolic compound, with PHE showing a remarkable 95% removal at a 3 ppm, 0.20 g of SnO
NPs, pH 8, and 30 min of agitation at 35 °C. Molecular docking studies unveiled a potential anticancer mechanism, indicating the ability of SnO
NPs to interact with the epidermal growth factor receptor tyrosine kinase domain and inhibit its activity. The adsorption processes followed pseudo-second order kinetics and Temkin isotherm model, revealing spontaneous, exothermic, and chemisorption-controlled mechanisms. This eco-friendly approach utilizing plant extracts was considered as a valuable tool for nano-sorbent production. The SnO
NPs not only exhibit promise in water treatment and also demonstrate potential applications in cancer therapy. Characterization techniques including scanning electron microscopy, UV-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy (XRD), and energy-dispersive X-ray spectroscopy (EDAX) provided comprehensive insights into the results.
Hydroxyapatite (HAp) attracts interest as a biomaterial for use in bone substitution or allografts. In the current work, biomaterial nanocomposites based on HAp and pectin were synthesized by using ...the double decomposition method, which involved using pectin extracted from fresh cladodes of the prickly pear, Opuntia ficus-indica. The crystallinity, purity, and several analytical techniques like Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were used to understand the surface’s shape. The results revealed that the produced HAp/pectin nanoparticles are pure, spherical, and amorphous. The spectroscopic data indicated a substantial interaction between HAp and pectin, specifically between Ca (II) and pectin hydroxyl and carboxyl groups. The presence of pectin showed a noticeable influence on the prepared nanocomposite texture and porosity. We further assess the antibacterial and antifungal activity of the developed nanocomposite against a number of pathogenic bacteria and fungi, evaluated by the well diffusion method. In the absence of pectin, the XRD analysis revealed that the HAp nanoparticles had 10.93% crystallinity. When the pectin concentration reached 10 wt.%, it was reduced to approximately 7.29%. All synthesized nanocomposites demonstrated strong antimicrobial activity against both Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria in addition to various fungi (e.g., Aspergillus fumigatus, Penicillium funiculosum, and Trichoderma viride). This study endorses the HAp/Pectin nanocomposite as an efficient antimicrobial material for biomedical advanced applications.
In this work, we presented a synthesis of a composite based on HAp and PEG 6000 using a new method of synthesis dissolution precipitation to be applied for application of wastewater purification from ...toxic metal ions. Multiple characterization methods were used to analyze the morphology and the structure of the well-prepared compounds including FT-IR, Raman, XRD, XPS, TGA and SEM were used to conduct a composite analysis. The adsorption effectiveness of this analysis towards Pb
2+
and various other hazardous metal ions found in sewage was assessed. Batch experiments were conducted to optimize the various operational parameters including adsorbent dose, temperature, pH, contact time, and initial concentration. The Langmuir isotherm was used to fit the data, and it predicted monolayer adsorption with a maximum capacity of 67 mg g
−1
for HAP PEG600 and 60 mg g
−1
for HAp. A pseudo-second-order equation fits the adsorption process well (0.961–0.971). The thermodynamic data support the spontaneous metal bonding to the composite receptor sites. Theoretical calculations showed that the interaction strength is very strong and gets stronger when the PEG6000 is deprotonated. The results presented here are supported by evidence acquired from experiments. Theoretical computation using Monte Carlo (MC) and Molecular Dynamic (MD) simulation models showed excellent affinity of prepared foams for the model ion Pb
2+
with highly negative adsorption energy values indicating vigorous interactions of Pb
2+
with the adsorbate surfaces.
Hydroxyapatite (HAp) synthesized through a wet chemical procedure was used to adsorb lead (II) from an aqueous solution. HAp was characterized using Fourier transform infrared, X-ray diffraction, ...Brunauer–Emmett–Teller analysis, and scanning electron microscopy. The removal of Pb
+2
was investigated using the factorial design approach to investigate the efficiency of different Pb
+2
concentrations, adsorption contact time, and HAp mass. The greatest Pb
+2
removal (98.94%) was obtained at a starting concentration of 50 mg/L, a contact period of 15 min, and a pH of 8. At 323 K, the isothermal adoption module was fitted to the Langmuir isotherms with a regression coefficient (
R
2
) of 0.96. The thermodynamic calculations revealed that the adsorption process was exothermic, spontaneous, and predominantly dominated by chemisorption. Furthermore, the maximum adsorption capacity (
Q
max
) at equilibrium was 90.18 mg/g, and the adsorption kinetics was specified by a pseudo-second-order kinetic model. Density functional theory and theoretical studies showed that the results of the experiment were correlated by the observation of a much higher negative E
ads
value for the lead ion adsorbate molecules as they attached to the surface of the adsorbent.
Phosphocalcic apatites have osteoconductive and bioactive properties that make them suitable for bone reconstruction. But, they are inactive against pathogenic microorganisms that can infect bone ...tissue. To overcome this limitation, we synthesized oxygen-doped phosphocalcic apatites that can release molecular oxygen as a bioactive molecule. We investigated how the calcium-to-phosphorus ratio (Ca/P) gave impacts on the chemical and structural composition of the oxygen-doped phosphocalcic apatites. We here used the double decomposition method, which involved mixing calcium nitrate and diammonium phosphate solutions in an ammonia buffer. We then characterized the products using several analysis, including infrared absorption spectroscopy, X-ray diffraction, thermal analysis, nitrogen adsorption-desorption, and elemental chemical analysis. It was found that the oxygen-doped phosphocalcic apatites were calcium-deficient and had a well-defined crystallinity at room temperature. After calcination at 900°C, the crystallinity improved further. The thermal analysis showed two mass losses: one at 50°C due to water adsorption and another at 450°C due to CO2 release. The specific surface area was about 100 ± 2 m2/g without any change with the Ca/P ratio. The quantity of molecular oxygen increased with the Ca/P ratio and reached an optimal value of the order of 3.6 ×10-4 mol for Ca/P=1/65 with the chemical formula of Ca9.9(PO4)6(OH)1.25(O2)0.74(CO3)0.01. It is important to make further analysis to know more about the properties of oxygenated apatite, and to combine this apatite with polymers purposely to have biomedical composites. It then can be concluded that the oxygen-doped phosphocalcic apatites could be a promising biomaterial for bone infection prevention and treatment. This research highlights an oxygenation treatment of phosphocalcic apatite and brings new ideas and possibilities for future research and development to get better understanding of the behavior of these biomaterials to be more effective, especially in the biological field. As a perspective, improving the biological properties in these biomaterials needs to be further explored, including experimental parameters for the obtainment of more conclusive results.
The objective of this work was to develop a process that allows the synthesis of an apatitic material of controlled composition and morphology, which could be used for medical and environmental ...applications. The adsorbent was synthesized, and characterized using scanning electron microscopy, nuclear magnetic resonance, Thermal analysis and other techniques, Atomic Force Microscopy, X-ray photoelectron spectroscopy and Total organic carbon. Different experimental parameters such as the effect of the amount of adsorbent, solution pH and temperatures and contact times were studied. Pseudo-order kinetics models were studied, and our data followed a pseudo second order. Experimental data were analyzed for both Langmuir and Freundlich models and the data fitted well with the Langmuir isotherm model. To understand the mechanism of adsorption, thermodynamic parameters like standard enthalpy, standard Gibbs free energy, and standard entropy were studied. The study indicated that the process is spontaneous, exothermic in nature and follow physisorption mechanisms. The novelty of this study showed surface of composite based of hydroxyapatite has the ability to highlight the surface designed for efficient removal of Cu2+ and Zn2+ ions, from aqueous solutions more than other studies.
•Natural biomaterials in powder form were synthesized using double decomposition and neutralization methods.•Synthesis methods have a significant impact on the adsorbent's ability to remove organic ...dye pollutants from an aqueous solution.•Adsorption capacity is higher in samples synthesized by the double decomposition calcined method.•Hydroxyapatite nanoparticles are efficient adsorbents for removing pollutants such as methylene blue from water.
Water pollution due to industrial discharges is a major problem in many countries as it can have adverse effects on the environment and human health. Among wastewater treatment processes, adsorption technique is widely used to reduce the harmful effects of many pollutants, including dyes. The main objective of this research is to characterize and evaluate the removal capacity of methylene blue (a cationic dye) from an aqueous solution using hydroxyapatite as a bio-adsorbent. Hydroxyapatite was prepared by two different methods and the resulting biomaterials were designated HAp A, HAp B, HAp C, and HAp D. A comparative study of methylene blue adsorption by these biomaterials was performed. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize these adsorbents. The effects of various experimental parameters such as contact time (5–120 min), concentration (5–90 mg/L), pH (6–12) and temperature (25–6°C) were studied. Adsorption studies revealed a removal efficiency of 88.88% at an initial MB concentration of 45 mg/L, an equilibrium time of 20 min, Basic pH and a temperature of 25 °C. The pseudo-second order kinetic model was used to describe the adsorption kinetics, while the Freundlich adsorption isotherm was used to describe the equilibrium adsorption process. This research suggests that the method of synthesis has a significant impact on the ability of the adsorbent to remove organic pollutants from dyes in an aqueous solution.
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Beauveria bassiana has a high insecticidal potential to control the tarnished plant bug, Lygus lineolaris, a significant pest of strawberries. Screening experiments showed that L. lineolaris adults ...were susceptible to several B. bassiana isolates. Another screening test with Coleomegilla maculata, a natural enemy found in strawberries, was also performed in order to select the isolate having lower entomopathogenic impact on this insect. Based on data obtained from both insect species and on the ecozone origin of the B. bassiana isolates, INRS-IP and INRS-CFL isolates were selected for further experiments. The LC₅₀ values of these two isolates against L. lineolaris adults were 7.8 x 10⁵ and 5.3 x 10⁵ conidia/ml, and average survival time (AST) values were 4.46 and 4.37 days at a concentration of 1 x 10⁸ conidia/ml respectively. Results also indicated that L. lineolaris nymphs are susceptible to the selected isolates. During field experiments, using a randomized block design with four replicates, INRS-IP and INRS-CFL isolates were applied at two rates (1 x 10¹¹ and 1 x 10¹³ conidia/ha) weekly during a period of 4 weeks. These multiple applications triggered a significant reduction of L. lineolaris nymphal populations in strawberries. Twenty-four days after the first application, a significant difference was observed between the mean population densities of surviving nymphs in all B. bassiana-treated plots (less than one insect per five plants) compared with those in control plots (four insects per five plants). During the field experiment, persistence of insecticidal activity and viability of B. bassiana conidia were also monitored. The results showed the presence of viable and infective conidia up to 6 days after each application on strawberry foliage. Moreover, the multiple applications of B. bassiana at the rate of 1 x 10¹³ conidia/ha triggered a significant reduction in strawberry fruit injuries induced by L. lineolaris feeding behaviour compared with the control plots.
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