Confined effect of water solution of ciprofloxacin in carbon nanotubes studied by Raman and Fourier Transform Infrared Spectroscopy methods

Formulation of biodegradable alginate-based nano-carriers for in-vitro drug delivery and antibacterial activity

Evaluation of the controlled release of ciprofloxacin (CIP.HCl) and the antibacterial efficacy of alginate (ALG)-based nanocarriers constitute the primary objectives of the current work. Herein, ALG-based nano-structures were prepared by the co-precipitation method and thoroughly analyzed using different characterization techniques, i.e., fourier transform infrared (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and zeta potential (ZP). The intense peaks emerged at 500, 545, and 750 cm-1 due to the CeO bond. Peaks that appeared at 550-600 cm-1 and 525 cm-1 are due to the stretching vibrations of FeO and ZnO bonds, respectively. Lowering of the peaks from 1640 to 1630 cm-1 and 1420 to 1384 cm-1 were observed in ALG-based nanocomposite (NC) due to the interaction of ALG with metal oxides (MO), which confirmed the formulation of CeO2/ZnFe2O4/ALG nanocomposite. The diffraction peaks at 28.6°, 56.6°, 76.5°, 37°, 47.9°, 62.3°, 74°, 13°, 21° confirmed the synthesis of MO (crystallite size 15.74 nm) and CeO2/ZnFe2O4/ALG (12 nm). In accordance with morphological studies, CeO2/ZnFe2O4 oxides had a uniform distribution throughout the relatively smooth and permeable surface of the ALG-based NC. Ciprofloxacin (CIP) was used as a model drug. Negative values of ZP revealed that CIP-loaded nanocomposite (CeO2/ZnFe2O4/ALG/CIP) had more stability than CeO2/ZnFe2O4/ALG. The maximum percentage of loading around 25 % on ALG NC was examined using the optical density (OD) method at pH 5.5. Correlation coefficients from the first order (0.971), Korsmeyer (0.9858), and Hixson (0.9021) models show the best-fitted models of the release profile in all circumstances. The release mechanism was investigated using various kinetics models. The controlled drug released was observed around 17 % at 40 °C after 3 h at pH 7.4, which is almost identical to the body temperature of a human, which is 37 °C. Similarly, after 24 h, sustained and controlled in-vitro release of the drug was studied, and it was 37, 72, and 74 % at pH 2.2, 7.4, and 9.4, respectively. Thus, prepared ALG-based NC is suitable for the controlled in-vitro release of (CIP.HCl). Metal oxides (CeO2/ZnFe2O4) and ALG-based nanocomposite (CeO2/ZnFe2O4/ALG) showed great antibacterial activity against Staphylococcus aureus (S. aureus) like 15 mm and 14 mm than Escherichia coli (E. coli).

Copolymers functionalized with quaternary ammonium compounds under template chain exhibit simultaneously efficient bactericidal and flocculation properties: Characterization, performance and mechanism

In this work, novel multifunctional cationic template copolymers with flocculation and sterilization capabilities were synthesized using a low-pressure ultraviolet (LP-UV) template polymerization method for the removal of kaolin and Escherichia coli (E. coli) from water. The influence of template agents on the structural performance of the copolymers was evaluated through characterization, which showed that template copolymer TPADM possesses a higher cationic charge density and a more complex rough surface, contributing to better flocculation performance than that of the non-template copolymer CPADM. Under optimal experimental conditions, TPADM-1 exhibited removal rates of 98.45% for kaolin and 99% for E. coli (OD600 =0.04), marginally outperforming the non-template copolymer. Simultaneously, TPADM-1 produced good adaptability to kaolin and E. coli wastewater in terms of wide pH, speculating that charge neutralization, adsorption bridging, patching, and sweeping simultaneously dominate the flocculation mechanism. Interestingly, SEM and 3D-EEM analysis confirm that the sterilization of E. coli occurs through two distinct functions: initially adsorption followed by subsequent cell membrane rupture and leakage of cellular contents, ultimately leading to cell death. This research further confirms the feasibility of the designed novel multifunctional copolymers for achieving simultaneous disinfection and turbidity removal, demonstrating practical applicability in real water treatment processes.

Raman spectral pattern recognition of breast cancer: A machine learning strategy based on feature fusion and adaptive hyperparameter optimization

Raman spectroscopy, as a kind of molecular vibration spectroscopy, provides abundant information for measuring components and molecular structure in the early detection and diagnosis of breast cancer. Currently, portable Raman spectrometers have simplified and made equipment application more affordable, albeit at the cost of sacrificing the signal-to-noise ratio (SNR). Consequently, this necessitates a higher recognition rate from pattern recognition algorithms. Our study employs a feature fusion strategy to reduce the dimensionality of high-dimensional Raman spectra and enhance the discriminative information between normal tissues and tumors. In the conducted random experiment, the classifier achieved a performance of over 96% for all three average metrics: accuracy, sensitivity, and specificity. Additionally, we propose a multi-parameter serial encoding evolutionary algorithm (MSEA) and integrate it into the Adaptive Local Hyperplane K-nearest Neighbor classification algorithm (ALHK) for adaptive hyperparameter optimization. The implementation of serial encoding tackles the predicament of parallel optimization in multi-hyperparameter vector problems. To bolster the convergence of the optimization algorithm towards a global optimal solution, an exponential viability function is devised for nonlinear processing. Moreover, an improved elitist strategy is employed for individual selection, effectively eliminating the influence of probability factors on the robustness of the optimization algorithm. This study further optimizes the hyperparameter space through sensitivity analysis of hyperparameters and cross-validation experiments, leading to superior performance compared to the ALHK algorithm with manual hyperparameter configuration.

Dibutyl Phthalate Adsorbed on Multiwalled Carbon Nanotubes Causes Fetal Developmental Toxicity in Balb/C Mice

This study investigated whether using multiwalled carbon nanotubes (MWCNTs) as a carrier for dibutyl phthalate (DBP) could delay the degradation rate of DBP in mice and increase its estrogen-like interference effect. Pregnant Balb/C mice were divided into four groups and exposed to different treatments via tail-vein injection every 3 days until gestational day 20. The female and male mice were then sacrificed for toxicological study. The results showed that the combination of MWCNTs and DBP resulted in a higher fetal mortality rate than if the mice were exposed to MWCNTs or DBP alone. H&E staining showed that the estrous period of the exposed mice was delayed, the development of oocytes was blocked in the combination group, the number of spermatogenic cells decreased, and the quality of sperm decreased. Our experiment showed that the expression levels of the genes involved in sex hormone synthesis in the testis and ovaries were significantly increased after combined treatment compared with the MWCNT group (p < 0.01). The study suggests that DBP degradation is delayed when absorbed on MWCNTs, which increases its estrogen-like interference and interferes with fetal development, ultimately leading to increased fetal mortality.

Synthesis of CuO/GO-DE Catalyst and Its Catalytic Properties and Mechanism on Ciprofloxacin Degradation

A new catalyst, copper oxide/graphene oxide-diatomaceous earth (CuO/GO-DE), was prepared by the ultrasonic impregnation method. The optimal conditions for catalyst preparation were explored, and its structure and morphology were characterized by BET, XRD, SEM, TEM, FTIR, Raman and XPS. By taking ciprofloxacin as the target pollutant, the performance and reusability of CuO/GO-DE to degrade antibiotic wastewater was evaluated, and the optimal operating conditions were obtained. The main oxidizing substances in the catalytic system under different pH conditions were analyzed, as well as the synergistic catalytic oxidation mechanism. The intermediate products of ciprofloxacin degradation were identified by LC-MS, and the possible degradation process of ciprofloxacin was proposed.

Lattice Distortion, Amorphization and Wear Resistance of Carbon-Doped SUS304 by Laser Ablation

Lattice distortion and amorphization of carbon-doped SUS304 by variation of the laser output were investigated in terms of phase formation and the bonding state. The laser output was changed by 10% in the range of 60% to 100% after covering the SUS304 with carbon paste. A graphite peak and expanded austenite (S-phase) peak were observed in the carbon-doped SUS304, and Rietveld refinement was performed to identify the lattice distortion. The lattice constant of SUS304 was initially 3.612 Å, but expansion lattice distortion occurred in the carbon-doped SUS304 as a result of the S phase formation and carbon doping, and the lattice constant increased to 3.964 Å (100% laser output). X-ray photoelectron spectroscopy analysis for the bonding state of the carbon-doped SUS304 showed that the sp²/sp³ ratio decreased from 3.21 (70% laser output) to 2.52 (100% laser output). The residual stress in the lattice was accumulated due to carbon doping by high thermal energy, which resulted in the formation of amorphous carbon. The bonding environment was represented by the I_D/I_G ratio using Raman analysis, and it increased from 0.55 (70% laser output) to 1.68 (100% laser output). During microstructure analysis of the carbon-doped SUS304, disordered structures by amorphization were observed in the carbon-doped SUS304 by the greater than 90% laser output. The amorphous carbon filled the lattice grains or voids to lubricate the surface, which improved the friction coefficient and wear rate from 0.23 and 7.63 mm³(Nm)^-110^-6 to 0.09 and 1.43 mm³(Nm)^-110^-6, respectively.

Dehydrogenation of methylcyclohexane over Pt-based catalysts supported on functional granular activated carbon

Herein, we developed the dehydrogenation of methylcyclohexane over Pt-based catalysts supported on functional granular activated carbon. Sulphuric acid, hydrogen peroxide, nitric acid and aminopropyl triethoxy silane were adopted to modify the granular activated carbon. The structural characterizations suggested that the carbon materials had a large surface area, abundant pore structure, and a high number of oxygen-containing functional groups, which influenced the Pt-based catalysts on the particle size, dispersion and dehydrogenation activity. The hydrogen temperature-programmed reduction technique was utilized to investigate the interaction between the active component Pt and the various functionalized granular activated carbon materials. The CO pulse technique revealed the particle sizes and dispersion of the as-prepared Pt-based catalysts. Finally, the Pt-based catalysts were successfully applied to study their catalytic activity in the dehydrogenation reaction of methylcyclohexane. The results showed that the Pt-based catalyst over granular activated carbon functionalized with sulphuric acid groups had a higher conversion of methylcyclohexane (63%) and a larger hydrogen evolution rate (741.1 mmol g_Pt ^-1 min^-1) than the other resulting Pt-based catalysts at 300 °C.