Superior adsorption and removal of doxorubicin from aqueous solution using activated carbon via thermally treated green adsorbent: isothermal, kinetic, and thermodynamic studies

Activated carbon from apricot seeds (ASAC) was successfully made using a low-cost, straightforward synthesis process. With the use of various instruments, including XRD, XPS, FT-IR, SEM, and TEM, the adsorbent was demonstrated. The surface area of the ASAC that was given was also shown to be 436.8 m2/g. It was discovered that the synthesized ASAC has a fantastic capacity to absorb the anti-cancer medication doxorubicin hydrochloride (DOX). Based on changes in temperature, pH, and DOX concentration, The DOX adsorption behaviour's mechanism was evaluated. The adsorption capacity of ASAC for DOX was greater at pH 6.0, according to experimental data as the adsorption capacity was discovered to be 951.13 mg/g. Adsorption equilibrium analysis revealed that, when compared to the other models, the Langmuir adsorption provided the best fit to the data that were collected. Additionally, The ASAC has validated the DOX activation energy of adsorption as a chemisorption technique. The kinetics of adsorption were shown to be fitted to pseudo-second-order kinetic model. The reaction was endothermic and spontaneous, according to thermodynamic data. Innvestigation the removal efficiency of ASAC to remove DOX from real watrer sample (tap water, effluent wastewater, and impact wastewater). It was suggested by the results that ASAC was a viable option for treating wastewater and adsorbing DOX. The synthesized ASAC has noteworthy cyclability and reusability characteristics due to its high efficiency (up to five cycles) and low cost (around 86 percent).

Functionalized Mesoporous Silica as Doxorubicin Carriers and Cytotoxicity Boosters

Mesoporous silica nanoparticles (MSNs) bearing methyl, thiol or glucose groups were synthesized, and their encapsulation and release behaviors for the anticancer drug Doxorubicin (Dox) were investigated in comparison with nonporous homologous materials. The chemical modification of thiol-functional silica with a double bond glucoside was completed for the first time, by green thiol-ene photoaddition. The MSNs were characterized in terms of structure (FT-IR, Raman), morphology (TEM), porosity (nitrogen sorption–desorption) and Zeta potential measurements. The physical interactions responsible for the Dox encapsulation were investigated by analytic methods and MD simulations, and were correlated with the high loading efficiency of MSNs with thiol and glucose groups. High release at pH 5 was observed in most cases, with thiol-MSN exhibiting 98.25% cumulative release in sustained profile. At pH 7.4, the glucose-MSN showed 75.4% cumulative release, while the methyl-MSN exhibited a sustained release trend. The in vitro cytotoxicity was evaluated on NDHF, MeWo and HeLa cell lines by CellTiter-Glo assay, revealing strong cytotoxic effects in all of the loaded silica at low equivalent Dox concentration and selectivity for cancer cells. Atypical applications of each MSN as intravaginal, topical or oral Dox administration route could be proposed.

Magnetite graphene oxide modified with β-cyclodextrin as an effective adsorbent for the removal of methotrexate and doxorubicin hydrochloride from water

The purpose of this investigation was to analyze the performance of magnetite graphene oxide modified with β-cyclodextrin (GO@Fe₃O₄@β-CD) for adsorption of methotrexate (MTX) and doxorubicin (DOX) from aqueous solutions. Characterization of GO@Fe₃O₄@β-CD was carried out using some methods. The perfect conditions for the adsorption of MTX and DOX were 7.0, 45 min, 20 mg, and 25 °C for solution pH, contact time, adsorbent dose, and temperature, respectively, with removal efficiency values of 97.8% and 98.5% for MTX and DOX, respectively. The adsorption kinetic of MTX and DOX via GO@Fe₃O₄@β-CD followed pseudo second-order (PSO) model, while the adsorption isotherm obeyed Langmuir model by monolayer adsorption with maximum adsorption capacities of 198.5 and 204.5 mg g^-1 for MTX and DOX, respectively. Therefore, it could be argued that HCl and 0.1 mol L^-1 NaOH would reflect adequate elution properties for GO@Fe₃O₄@β-CD recovery.

Adsorption and Release of Sulfamethizole from Mesoporous Silica Nanoparticles Functionalised with Triethylenetetramine

Mesoporous silica nanoparticles (MSN) were synthesised and functionalised with triethylenetetramine (MSN-TETA). The samples were fully characterised (transmission electron microscopy, small angle X-ray scattering, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential and nitrogen adsorption/desorption isotherms) and used as carriers for the adsorption of the antimicrobial drug sulphamethizole (SMZ). SMZ loading, quantified by UV-Vis spectroscopy, was higher on MSN-TETA (345.8 mg g-1) compared with bare MSN (215.4 mg g-1) even in the presence of a lower surface area (671 vs. 942 m2 g-1). The kinetics of SMZ adsorption on MSN and MSN-TETA followed a pseudo-second-order model. The adsorption isotherm is described better by a Langmuir model rather than a Temkin or Freundlich model. Release kinetics showed a burst release of SMZ from bare MSN samples (k1 = 136 h-1) in contrast to a slower release found with MSN-TETA (k1 = 3.04 h-1), suggesting attractive intermolecular interactions slow down SMZ release from MSN-TETA. In summary, the MSN surface area did not influence SMZ adsorption and release. On the contrary, the design of an effective drug delivery system must consider the intermolecular interactions between the adsorbent and the adsorbate.

Fabrication of the magnetic mesoporous silica Fe-MCM-41-A as efficient adsorbent: performance, kinetics and mechanism

Antibiotics are emerging pollutants and increasingly present in aquaculture and industrial wastewater. Due to their impact on the environment and health, their removal has recently become a significant concern. In this investigation, we synthesized nano zero-valent iron-loaded magnetic mesoporous silica (Fe-MCM-41-A) via precipitation and applied the adsorption of oxytetracycline (OTC) from an aqueous solution. The effects of competing ions such as Na⁺, Ca²⁺ and Cu²⁺ on the adsorption process under different pH conditions were studied in depth to providing a theoretical basis for the application of nanomaterials. The characterization of the obtained material through transmission electron microscopy demonstrates that the adsorbent possesses hexagonal channels, which facilitate mass transfer during adsorption. The loaded zero-valent iron made the magnetic, and was thus separated under an applied magnetic field. The adsorption of OTC onto Fe-MCM-41-A is rapid and obeys the pseudo-second-order kinetic model, and the maximum adsorption capacity of OTC is 625.90 mg g^-1. The reaction between OTC and Fe-MCM-41-A was inner complexation and was less affected by the Na⁺. The effect of Ca²⁺ on the adsorption was small under acidic and neutral conditions. However, the promotion effect of Ca²⁺ increased by the increase of pH. Cu²⁺ decreased the removal efficiencies continuously and the inhibitory effects decrease varied with the increase of pH. We propose that surface complexing, ion-exchange, cationic π-bonding, hydrogen bonding, and hydrophobicity are responsible for the adsorption of OTC onto Fe-MCM-41-A.

Fluorometer for Screening of Doxorubicin in Perfusate Solution and Tissue with Solid-Phase Microextraction Chemical Biopsy Sampling

The recent development of an in vivo solid-phase microextraction (SPME) method capable of analyzing drugs and metabolic products in biofluids and living tissues holds great promise. The standard in vivo SPME protocol based on mass spectrometry is a very powerful analytical approach, but it is not practical for on-site analysis in many cases. In this paper, we present a fluorescence-based SPME method and a prototype of a portable fluorometer that is capable of quickly quantifying concentrations of the anticancer drug, doxorubicin (DOX). The instrument uses thin coated, biocompatible SPME fibers, which we have previously presented as a chemical biopsy tool for use during in vivo lung perfusion (IVLP) procedures within a hospital setting. In this research, we test SPME fibers with C8-SCX, C18, and HLB coatings with our fluorometer. The mixed-mode C8-SCX fibers showed the best sensitivity of the three and were therefore used to examine DOX extraction from perfusate solution and a homogenized lamb lung tissue. The maximum concentration of free active sites in the C8-SCX fiber and the adsorption equilibrium constant were determined to be (9.1 ± 0.3) × 10^-7 mol m^-2 and 420 ± 30 m³ mol^-1, respectively. Finally, the detection limits for DOX extracted from buffer, perfusate, and lung tissue were 40, 100, and 3700 μg L^-1, respectively.

Ethanol-activated granular aerogel as efficient adsorbent for persistent organic pollutants from real leachate and hospital wastewater

Hydrophobic aerogels were used to remove three types of persistent organic pollutants: pharmaceutical drugs (i.e. doxorubicin [DOX], paclitaxel [TAX]), phthalates (diethyl phthalate [DEP]), and hydrophilic rhodamine dye (RhB) from synthetic and real wastewaters, using Lumira granular aerogel from Cabot activated with EtOH (ET-GAG). The hydrophobic silica aerogel was characterized by X-ray diffraction (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), Brunauer-Emmet-Teller (BET) and attenuated total reflection-Fourier transform infrared spectroscopy. The pollutants were analysed by high-performance liquid chromatography (HPLC)-UV and HPLC-mass spectrometry. The adsorption process was governed by hydrophobic- hydrophobic interactions between the ET-GAG and micropollutants. The adsorption capacity of ET-GAG, examined by batch experiments, for DOX, TAX and DEP were 13.80, 14.28 and 17.54 mg/g respectively. The rate of adsorption to ET-GAG is high in the initial 40 min followed by no change in the rate due to saturation of adsorption sites. ET-GAG was able to completely remove micropollutants from real leachate and hospital wastewater, implying practical applications. Regeneration of the aerogel was studied by solvent extraction. Et-GAG adsorbent demonstrated better removal of toxic chemotherapeutic drugs and phthalates than GAC.

Removal of doxorubicin by magnetic copper phosphate nanoflowers for individual urine source separation

Doxorubicin (DOX) originated from users' urine has been an emerging environmental pollutant due to its significant genotoxicity to mankind. Thus, urine source separation is a potential strategy to isolate DOX at a higher concentration and reduce the burden of downstream wastewater treatment. To develop highly efficient, easy separation and retrievable materials for individual patient to conveniently remove DOX from own urine, magnetic Cu₃(PO₄)₂ nanoflowers were prepared through anchoring amino-functionalized magnetic nanoparticles on the Cu₃(PO₄)₂ nanoflowers. Characterizations revealed the magnetic nanoflowers were spherical in shape with a mean size of 15 μm, and porous and hierarchical in structure. Magnetic nanoparticles located the surface of petals. Multibatch experiments were performed to assess the removal performance of DOX from aqueous solution. The magnetic nanoflowers exhibited excellent removal efficiency of DOX under weakly alkaline condition at ambient temperature. Linear and non-linear analyses were carried out to compare the best fitting kinetics and isotherms. Sorption kinetic data best fitted the pseudo-second order model. The Freundlich isotherm explained equilibrium sorption data with R² = 0.993 higher than that for the Langmuir isotherm. When the pH of synthetic urine was adjusted to weakly alkaline (pH 8.0-9.0), over 95% of DOX (20 mg L^-1) was removed by a little of magnetic nanoflowers (50 mg L^-1) within 5 min. Meanwhile, the magnetic nanoflowers could be easily separated and recovered from the synthetic urine by a magnet. So, for individual urine source separation strategy, the magnetic nanoflower seems to be an efficient, convenient and inexpensive approach to remove DOX from human urine.

Silica-Polymer Composites as the Novel Antibiotic Delivery Systems for Bone Tissue Infection

Bone tissue inflammation, osteomyelitis, is commonly caused by bacterial invasion and requires prolonged antibiotic therapy for weeks or months. Thus, the aim of this study was to develop novel silica-polymer local bone antibiotic delivery systems characterized by a sustained release of ciprofloxacin (CIP) which remain active against Staphylococcus aureus for a few weeks, and do not have a toxic effect towards human osteoblasts. Four formulations composed of ethylcellulose (EC), polydimethylsiloxane (PDMS), freeze-dried CIP, and CIP-adsorbed mesoporous silica materials (MCM-41-CIP) were prepared via solvent-evaporation blending method. All obtained composites were characterized in terms of molecular structure, morphological, and structural properties by using Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM/EDX), and X-ray diffraction (XRD), thermal stability by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), and in vitro antibiotic release. The antibacterial activity against Staphylococcus aureus (ATCC 6538) as well as the in vitro cytocompatibility to human osteoblasts of obtained composites were also examined. Physicochemical results confirmed the presence of particular components (FTIR), formation of continuous polymer phase onto the surface of freeze-dried CIP or MCM-41-CIP (SEM/EDX), and semi-crystalline (composites containing freeze-dried CIP) or amorphous (composites containing MCM-41-CIP) structure (XRD). TGA and DSC analysis indicated the high thermal stability of CIP adsorbed onto the MCM-41, and higher after MCM-41-CIP coating with polymer blend. The release study revealed the significant reduction in initial burst of CIP for the composites which contained MCM-41-CIP instead of freeze-dried CIP. These composites were also characterized by the 30-day activity against S. aureus and the highest cytocompatibility to human osteoblasts in vitro.