Uptake of propranolol on ionic liquid iron nanocomposite adsorbent: Kinetic, thermodynamics and mechanism of adsorption

Biogenic platinum nanoparticles using black cumin seed and their potential usage as antimicrobial and anticancer agent

Herein, the biogenic platinum nanoparticles (Pt NPs) were synthesized by using black cumin seed (Nigella sativa L.) extract as a reducing agent. The biogenic platinum nanoparticles synthesized by black cumin seed extract was characterized in detail by Transmission Electron Microscopy (TEM), UV-vis spectrophotometer, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). According to TEM analysis, Pt nanoparticles have spherical shapes and sizes between 1-6 nm. Moreover, the biogenic Pt NPs was assessed for its cytotoxicity effect on MDA-MB-231 breast and HeLa cervical cancer lines and their antibacterial effect against selected strains of gram-positive and negative bacteria. The cytotoxicity and bacterial tests showed the effectiveness of biogenic Pt nanoparticles. Dose-dependent toxicity effects were shown in the MDA-MB-231 breast and HeLa cervical cancer lines (IC50: 36.86 μg/mL and 19.83 μg/mL, respectively). In addition, Pt NPs showed high zone diameters against gram-positive and gram-negative bacteria at concentrations of 100 and 500 μg/ml. These results contribute to the development of the pharmaceutical industry as a potential antibacterial and anticancer agent.

Potentiality of the Phoma sp. inactive fungal biomass, a waste from the bioherbicide production, for the treatment of colored effluents

The potentiality of Phoma sp. inactive fungal biomass, waste from the bioherbicide production, was evaluated for the treatment of colored effluents containing Acid Red 18 (AR 18) dye. The batch experiments were performed to evaluate the following parameters: pH of the solution (2-10), dye concentration (50-200 mg L^-1), adsorbent dose (0.5-2.5 g L^-1), contact time (0-180 min) and temperature (298-328 K). The batch experiments using a synthetic dye solution revealed that Phoma sp. was efficient at pH of 2.0, 298 K and using a dosage of 1.25 g L^-1. The process was fast, being the equilibrium reached within 180 min. The maximum value of biosorption capacity was 63.58 mg g^-1, being the process favorable and exothermic. From the fixed bed assays, breakthrough curves were obtained, presenting a mass transfer zone of 7.08 cm and breakthrough time of 443 min. Phoma sp. was efficient to decolorize a simulated effluent, removing more than 90% of the color. From the obtained results, it can be concluded that Phoma sp. inactive biomass is a low-cost option to treat colored effluents in continuous and discontinuous biosorption modes. These indicate that Phoma sp. of inactive biomass is an option for the treatment of colored effluents.

Indolocarbazole based polymer coated super adsorbent polyurethane sponges for oil/organic solvent removal

The synthesis of an indolocarbazole-fluorene based conjugated polymer (ICZP6), by Sonogashira coupling reaction, has been presented. The ICZP6 has then been integrated with a nano iron oxide embedded polyurethane foam (ICZP6PUF) to develop a promising adsorbent for oil/organic contaminants in aqueous systems. The anchoring ability of ICZP6 on to iron oxide PU sponge switches on significant hydrophobicity within the whole molecular assembly. The cooperative effects of ICZP6-iron oxide- PU sponge system have been highlighted in terms of structural, microscopic and wettability characteristics. The heterogeneity and hierarchical porous structure of the system offer a high adsorption capability for different types of oils and organic contaminants in water, typically in the range of 100-240 gg^-1. The performance of ICZP6PUF has been confirmed by the fast (within 5-10s) and choosy removal of selected oils and organic solvents from polluted water with the aid of an external magnetic field. The adsorbed materials (oil/organic solvents) can be separated from the adsorbent by simple mechanical squeezing without causing any structural deformation or performance deterioration; with a reusability of the system over 50 cycles. The adsorption isotherm has been found to fit well with the Langmuir model with R² = 0.9484. To extent the scope of the ICZP6PUF hybrid, an integrative logic gate has been designed.

New Insights into the Interaction between Graphene Oxide and Beta-Blockers

As a nano-adsorbent, magnetic graphene oxide (GO/Fe3O4) was synthesized to potentially adsorb propranolol (PRO) from water. The synthetic material was characterized by SEM, TEM, VSM, FTIR, XRD, zeta potential, and XPS. The environmental factors, such as pH, humic acid concentration, PRO concentration, and contact time, were investigated regarding their effect on the adsorption process. The kinetics data fitted the pseudo first-order and second-order kinetics equations. The Langmuir equation, the Freundlich equation, and the Sips equation were used to analyze the adsorption isotherms. Electrostatic attraction, hydrogen bonding, and the π-π interaction all contributed to the adsorption process of PRO onto GO/Fe3O4. The discovery of this study emphasized the feasibility of GO/Fe3O4 removal of PRO and expanded the scope of the application of GO.

Role of Unani Medicines in Cancer Control and Management

Background:

Cancer is a havoc and killer disease. Several ways including allopathic chemotherapy have been used in the cancer treatment. Allopathic chemotherapy has several limitations and side effects. Unani medicine is also one of the therapies to cure cancer.

Objective:

In this type of treatment, herbal drugs are used for the treatment and prevention of cancer. The main attractive thing about herbal drug is no side effect as compared to allopathic chemotherapy.

Methods:

Actually, herbal drugs are the extracts of medicinal plants. The plant extracts are obtained by crushing and heating the main part of the plants; showing anticancer activity. The main plants used in the treatment of cancer are oroxylum indicum, dillenia indica, terminalia arjuna etc.

Results:

Mainly the cancers treated are of digestive system, breast, cervical, brain, blood, bone, lungs, thyroid, uterine, bladder, throat etc.

Conclusion:

The present review article discusses the importance of Unani system of medicine for the treatment of cancer. Besides, the future perspectives of Unani medicine in cancer treatment are also highlighted.

Effect of the mole ratio of Mn/Fe composites on arsenic (V) adsorption

Iron and manganese have been studied as a proposal for new materials that could be used for the adsorption of arsenic (V) (As (V)), in order to remove this contaminant. The objective of this work was to study the effect of the molar ratio of three Mn/Fe+Mn composites (X=0.17, 0.32, 0.47) on the properties of adsorbent media, and to determine their influence on arsenic removal by comparing them with two metallic oxyhydroxides, that are commonly used as adsorbents of As(V) in aqueous solution (goethite and birnessite). These media were synthesized by chemical precipitation while controlling particle size. They were characterized using X-ray diffraction (XDR), scanning electron microscopy with X-ray dispersive energy spectrometry (SEM-EDS), surface area analysis by the BET method, Fourier transform infrared spectroscopy (FTIR), and isoelectric point analysis (IEP). The surface area (286m²/g) of the composite with a molar ratio of X=0.17 was larger than that of the other media. The adsorption kinetics and isotherms were fitted to the mathematical models, specifically, the pseudo-second order and Langmuir, respectively. The X=017 composite had an adsorption capacity of 3.28mg/g and removed 99% of As(V) with an initial concentration of 0.5 and 97% with an initial concentration of 10mg/L, at 180min, 25°C, and pH7. The five adsorbent media were tested with well water with an initial As(V) concentration of 0.075mg/L, and the best behavior was exhibited with a molar ratio of X=0.17 at 90min, resulting in 100% removal of As(V). The results suggest that this material is an effective and viable alternative to remove this contaminant from water.

Graphene based adsorbents for remediation of noxious pollutants from wastewater

The contamination of water resources with noxious pollutants is a serious issue. Many aquatic systems are contaminated with different toxic inorganic and organic species; coming to wastewater from various anthropogenic sources such as industries, agriculture, mining, and domestic households. Keeping in view of this, wastewater treatment appears to the main environmental challenge. Adsorption is one of the most efficient techniques for removing all most all types of pollutants i.e. inorganics and organics. Nowadays, graphene and its composite materials are gaining importance as nano adsorbents. Graphene; a two-dimensional nanomaterial having single-atom graphite layer; has attracted a great interest in many application areas (including wastewater treatment) due to its unique physico-chemical properties. The present paper is focused on the remediation of noxious wastes from wastewater using graphene based materials as adsorbents, and it contains all the details on materials - i.e., from their synthesis to application in the field of wastewater treatment (removal of hazardous contaminants of different chemical nature - heavy and rare-earth metal ions, and organic compounds - from wastewater effluents. The efficiency of the adsorption and desorption of these substances is considered. Certainly, this article will be useful for nano environmentalist to design future experiments for water treatment.

Preparation of a carboxymethylcellulose-iron composite for uptake of atorvastatin in water

Many water bodies are being contaminated by atorvastatin, which has certain side effects and problems on healthy individuals through contaminated water. For this purpose, effective and selective carboxymethylcellulose macromolecule iron composite nanoparticles were synthesized by green methods, characterized and used for uptake of atorvastatin drug residue from water. Atorvastatin in water was analyzed by HPLC using Aqua C₂₈ (250 mm × 46 mm id) column and buffer-ACN (35:65, v/v) as eluent. The maximum elimination of atorvastatin was 80% with 40 μg L^-1 concentration; 40 min agitated time, 5.0 pH, 1.0 g L^-1 dose and 298 K temp. The removal data obeyed Freundlich, Langmuir, Dubinin-Radushkevich and Temkin models. The values of free energy were -8.79, -8.73 and -8.65 kJ mol^-1 at 20.0, 25.0 and 30.0 °C temperatures. Enthalpy value was -14.16 kJ mol^-1; showing exothermic removal. Entropy was -18.74 × 10^-3 kJ mol^-1 K; presenting decrease in entropy in the process. The kinetics modeling showed pseudo-first-order and liquid film diffusion mechanisms of removal. The removal technology was quick, conservation pleasant and lucrative. It is because of it capability with little dose and interaction time. Hence, the reported technology is practical for the exclusion of atorvastatin in water resource.

Fast Removal of Propranolol from Water by Attapulgite/Graphene Oxide Magnetic Ternary Composites

In this work, a novel adsorbent attapulgite/graphene oxide magnetic composite (ATP/Fe₃O₄/GO) was synthesized for removing propranolol (PRO) from aqueous water. The factors affecting the PRO adsorption process onto ATP/Fe₃O₄/GO including pH, ionic strength, sorbent dosage, and humic acid were systematically investigated by batch experiments. Meanwhile, magnetic attapulgite (ATP/Fe₃O₄) and magnetic graphene oxide (GO/Fe₃O₄) were prepared for the comparison of the adsorption performance for PRO. The structural and surface characteristics of the resulting materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, zeta potential measurements, and scanning electron microscope. The results showed that the adsorption rate of PRO onto ATP/Fe₃O₄/GO was up to 99%, faster and higher than that of other adsorbents involved at neutral pH. Moreover, the adsorption kinetics were better fitted with pseudo-first-order kinetic model than the second-order kinetic model. The adsorption data were fitted well with the Freundlich isotherm equations, implying that the adsorption process was heterogeneous. The adsorption reaction was endothermic and spontaneous according to the thermodynamic parameters. All results indicated that ATP/Fe₃O₄/GO was a promising adsorbent for removing PRO from water.

Phenolic metabolism and related heavy metal tolerance mechanism in Kandelia Obovata under Cd and Zn stress

In the present study, a set of pot culture experiments was conducted to reveal how the metabolism process of phenolic compounds was affected by cadmium (Cd) and zinc (Zn) and to further uncover heavy metal tolerance mechanisms in Kandelia obovata. After 60d of treatment, the biomass and chlorophyll a content in the leaves were suppressed, but total phenolic compounds in roots and leaves were improved by the increasing gradient of Cd or Zn concentrations; Total phenolic compounds significantly increased by 3.6-44.6% in the roots, and by 0.4-126.6% in the leaves. At the meantime, the activity of Shikimate dehydrogenase (SKDH), cinnamyl alcohol dehydrogenase (CAD), and polyphenol oxidase (PPO) in the roots increased by 11.2-307.6%, 12.4-175.4% and - 2.7-392.8%, and the results were 3.4-69.5%, 1.7-40.0%, 16.0-99.7% in the leaves. Higher toxicity of Cd than Zn, as well as slight alleviating effect of 100 mg kg^-1 Zn on 2.5 mg kg^-1 Cd were found. Additionally, a significantly positive correlation coefficients for relationship between phenolic metabolism related enzyme activity and Cd/Zn contamination levels was found, and leaf SKDH, leaf CAD, and leaf PPO activities were moderately correlated with leaf Cd (r = 0.39, r = 0.43, and r = 0.57, respectively) and leaf Zn (r = 0.44, r = 0.41, r = 0.19, respectively) content, which indicate that Cd and Zn play a previously unrecognized but major role in phenolic compounds synthesis, transport, and metabolism in K. obovata. The results also provided evidence that the application of high levels of Cd and Zn was accompanied by three phenolic metabolism pathways participating in heavy metal tolerance process.

Modeling of fenuron pesticide adsorption on CNTs for mechanistic insight and removal in water

Inexpensive multi-walled carbon nanotubes (MCNTs) were prepared with 10-40 nm particle sizes and 9.0 m²g^-1 surface area. Fenuron pesticide was removed in water using these CNTs with 100.0 µgL^-1 concentration, 60 min contact time, 2.0 g L^-1 dose, 7.0 pH, and 25 °C. 90% removal of fenuron pesticide was achieved. Adsorption data obeyed Tempkin, Freundlich, Langmuir and Dubinin-Radushkevich models. The standard free energies values of fenuron pesticide adsorption were -11.89, -11.59, -11.55 kJ mol^-1. The values of enthalpy and entropy were -9.12 kJmol^-1 and -26.61 × 10^-3 kJ mol^-1 K. The negative values of free energy showed speedy adsorption of fenuron pesticide on CNTs. The supramolecular mechanism of fenuron adsorption onto CNTs was fixed by simulation studies and the binding energy and binding affinity of fenuron with CNTs were - 6.5 kcal mol^-1 and 5.85 × 10⁴ M^-1, respectively. There were one π-σ, seven π-π stacked, one π-π T-shaped, and three π-alkyl type of hydrophobic interactions between fenuron and carbon nanotube. These results clearly indicated the physical nature of the adsorption. The method is speedy, cost-effective, efficient and repeatable. Therefore, the established adsorption method is appropriate for adsorption of fenuron pesticide in waters.

Chiral pharmaceuticals: Environment sources, potential human health impacts, remediation technologies and future perspective

Chiral pharmaceuticals (CPs), including non-steroid anti-inflammatory drugs (NSAIDs), β-blockers and some herbicide and pesticides, are widely used in aquaculture, clinical treatment and many other fields. However, people are increasingly concerned about such ubiquitous pollutants, which can frequently be detected in contaminated soil and water. In large part, the significant sources of chiral pharmaceuticals stem from industrial processes, such as the direct discharge of untreated or incompletely treated wastewaters containing chiral pharmaceuticals, incorrect storage and use, animal wastes and biosolids. The main ways for human exposure to chiral pharmaceuticals are the disease treatment process and chiral pharmaceuticals contaminants. According to the results of a series of toxic studies, some diseases, even cancers, may be associated with exposure to certain chiral pharmaceuticals. Therefore, the treatment of chiral pharmaceuticals has become an important issue. The current advanced remediation techniques for chiral pharmaceuticals include the conventional method (sorption and sonolysis), biotransformation (an aerobic granular sludge-sequencing batch reactor and constructed wetland system) and advanced oxidation processes (ozonation and photocatalysis). Herein, in this review, we summarize the current status and sources of chiral pharmaceuticals, potential effects on human health, as well as the superiority, disadvantages and prospects of current advanced remediation technologies. Moreover, we also anticipate the prospect of the future research needed for chiral pharmaceuticals pollutant remediation.

Integrating natural and engineered remediation strategies for water quality management within a low-impact development (LID) approach

The objective of this paper is to demonstrate an interdisciplinary strategy combining both engineering- and biology-based approaches for stormwater and wastewater treatment. The work involves a novel and environmentally friendly surface material that can withstand urban load over its design service life, allows preliminary treatment through filtration, and diverts water to the subsurface to conduct secondary treatment below the surface through phytoremediation via the extensive rooting systems of trees. The present study highlights an interdisciplinary low-impact development (LID) approach developed for a polluted industrial wastewater site, for a cleaner and greener environment. The LID system involves (i) rhizofiltration and phytoremediation methods for removing heavy metals and organic pollutants using a hybrid poplar and aspen species; (ii) porous infrastructure produced using industrial waste, referred to as geopolymer pavers; and (iii) use of Silva cells as a tree-friendly and load support system. The design of the pavers over the Silva cells is innovative as it can deal with rainwater runoff and urban transportation loads simultaneously. The proposed system has the ability to extract heavy metals that are common in urban runoff or domestic and industrial effluents thus preserving the ecosystem naturally. The test site is only 15 m², but designed for a water-retention capacity of 2 m³ (roughly 1:100 year design volume draining a 10 × 10 m parking lot), and remediation levels for Cu and Zn are expected to reach 180 mg/kg dry weight and 1200 mg/kg dry weight, respectively.

Quantitative contribution of Cd2+ adsorption mechanisms by chicken-manure-derived biochars

This study investigated the efficiency and mechanisms of Cd²⁺ removal by chicken-manure biochar produced at different temperatures. Adsorption kinetics, isotherms, thermodynamic, and desorption were examined, and the biochars before and after adsorption were analyzed by SEM-EDS, FTIR, Boehm titration, and XRD. Kinetics of adsorption were better described by pseudo-second-order kinetic model than pseudo-first-order kinetic and intraparticle diffusion model under different initial Cd²⁺ concentrations of 20, 50, and 100 mg L^-1. Equilibrium adsorption was better modeled by Freundlich and Temkin isotherm equations than Langmuir equation at different temperatures of 25, 35, and 45 °C. Thermodynamic parameters confirmed the spontaneous and endothermic nature of the adsorption of Cd²⁺ at all of temperatures. Moreover, functional group complexation, precipitation, and cation exchange jointly contributed to Cd²⁺ adsorption on the biochars, whose relationship with the properties of biochar were also analyzed. The new precipitate as Cd₅(PO₄)₃OH was found during the adsorption. Complexation and precipitation were predominant mechanisms for all biochars (together accounting for 92.4-98.8%), while cation exchange made a relatively minor contribution to total Cd²⁺ removal (accounting for 1.2-7.6%). The relative distribution of each mechanism on the biochars was determined, which deepen our understanding of the Cd²⁺ adsorption process. These results are useful for future practical applications of biochar to removal heavy metals from water.

Efficacy of spent black tea for the removal of nitrobenzene from aqueous media

Nitrobenzene (NB) is a kind of persistent organic pollutant. A ubiquitous and cost-effective substance spent black tea (SBT) was investigated for the removal of nitrobenzene from aqueous media. The maximum uptake potential of dried biomass (SBT) for NB was found to be 14.86 mg per gram (q_max) in a batch experimental set-up. Equilibration time for NB sorption was about 50 min, and optimal removal efficiency was achieved at a dosage of 2 g/L with an initial concentration of 100 mg/L of NB. Findings revealed that NB uptake increased with an increase in the temperature from 273 K to 353 K. Sorption was also found to be pH sensitive, sorption improved as the pH value changes from alkaline to acidic (from 10 to 2). Different isotherm (Langmuir, Freundlich, Temkin and Dubinin Radushkevich) and kinetic models (pseudo-1st order, pseudo-2nd order and Elovich models) were applied to experimental results; the sorption mechanism was well described by the Freundlich and pseudo-2nd order models. Moreover, Scanning electron micrographs, ATR-FTIR spectra and the results of elemental analysis also supported the efficacy of SBT as an efficient bio-sorbent for the elimination of NB from water.

Removal of aromatic and hydrophobic fractions of natural organic matter (NOM) using surfactant modified magnetic nanoadsorbents (MNPs)

The present study investigated the potential of surfactant modified magnetic nanoadsorbents (MNPs) for the removal of aromatic and hydrophobic fractions of natural organic matter (NOM), leading to the formation of trihalomethanes (THMs) in chlorinated drinking water. Co-precipitation method was used for the synthesis of MNPs. However, MNPs have a tendency to form an agglomeration. Therefore, polyethylene glycol (PEG) was used as a surface modifier to reduce the agglomeration. The PEG-coated MNPs were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), BET surface area, X-ray diffraction (XRD), Fourier transform spectrometer (FTIR), and zeta (ζ) potential. FESEM observation indicates that PEG-coated MNPs were spherical in shape and 25 nm in size. Zeta potential values (- 58.35 to - 74.9 mV) indicated excellent stability of PEG-MNPs. FTIR spectra indicated the presence of a -CH₂ group, responsible for the chemical interaction between aromatic and humic content. Batch experiments were conducted by studying the effect of pH, contact time, and adsorbent dosage on NOM removal. Excellent removal of DOC (94.49%) and UV₂₅₄ (89.32%) was observed at the optimum dose of adsorbent (0.75 g/L) and at pH 7.0. Adsorption kinetics followed pseudo-second-order reaction (R², 0.973) and occurs by multilayer chemisorption which is due to the chemical interaction between aromatic and humic compounds of NOM with MNPs. Thus, MNPs showed great potential as a novel adsorbent for the removal of aromatic and hydrophobic compounds of NOM and can significantly be used to curtail the problem of THMs in drinking water supplies.

Preparation and characterization of CS/β-CD/Nano-ZnO composite porous membrane optimized by Box-Behnken for the adsorption of Congo red

In this paper, an effective chitosan/beta-cyclodextrin/nanometer zinc oxide (CS/β-CD/Nano-ZnO) composite porous membrane was synthesized by sol-gel and polymer-assisted inverting method. Preparation conditions of CS/β-CD/Nano-ZnO were investigated by single-factor and Box-Behnken response surface methodology optimizing triethoxyvinylsilane (JH-V151), beta-cyclodextrin (β-CD), and nanometer zinc oxide (Nano-ZnO), and applied to study the adsorption characteristics of Cong red (CR) from aqueous solution using batch experiments. The optimum preparation conditions were determined that the volume fraction of JH-V151 alcohol solution was 11%, the ratio of β-CD to CS was 5.35, and the ratio of Nano-ZnO's mass to solution's volume was 0.36%. Different characterization methods including field-emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV-visible spectroscopy, and Universal Materials Tester were used to prove the appearance, crystallinity, functional groups, swelling degree, transmittance, and tensile property of CS/β-CD/Nano-ZnO. The optimized batch experimental parameters were 50 mg L^-1, 4 h, 7.0, 0.5 g L^-1, and 55.0 °C as initial concentration, contact time, pH, adsorbent dose, and temperature, respectively. The maximum adsorption capacity on CR reached 96.33 mg g^-1, which is 4.34 times with respect to CS. The batch experimental data were best described by a pseudo-second-order kinetics model and Langmuir isotherm model (R² = 0.9965, theoretical saturated adsorption capacity 147.28 mg g^-1). The values ∆G were - 2.09, - 4.73, and - 7.37 kJ mol^-1 at 298, 308, and 318 K temperatures, respectively. The ∆H value was 76.68 kJ mol^-1, indicating the endothermic and spontaneous adsorption in nature. The ∆S value was 0.26 kJ mol^-1 K^-1, a signal of entropy increase during adsorption. The adsorption capacity decreased only by 5.8% after six recycling runs, which indicated the reusability of CS/β-CD/Nano-ZnO. Therefore, the CS/β-CD/Nano-ZnO composite porous membrane is a promising membrane material for the efficient removal of CR from any water at large and economic scales at moderate concentration.

Characterization of potassium hydroxide modified anthracite particles and enhanced removal of 17α-ethinylestradiol and bisphenol A

Anthracite is a natural inorganic-organic hybrid environmentally friendly material, which often is used as a filter medium in water treatment. In this study, we processed anthracite particles using potassium hydroxide (KOH) with different concentrations. The anthracites, before and after treatments, were characterized by Brunauer-Emmett-Teller analysis, scanning electron microscopy, Fourier transform infrared spectrometer, X-ray diffraction, X-ray photoelectron spectroscopy, and Boehm titration. The specific surface area and the amount of total alkalinity of anthracite were 23.73 m² g^-1 and 0.38 mmol g^-1 (increased by 101 and 217%, respectively) for 4 M KOH treatments, but decreased to 10.09 m² g^-1 and 0.12 mmol g^-1 for 10 M KOH treatments. We selected 4 M KOH-modified anthracite particles to remove 17α-ethinylestradiol (EE2) and bisphenol A (BPA) from water with unmodified anthracite used in control experiments. The pseudo-second-order model fitted well for the whole adsorption process, and intraparticle diffusion was not the unique rate-controlling step. The equilibrium adsorption data fitted well with the Langmuir-Freundlich model, and the adsorption capacities of EE2 and BPA on anthracite particles after 4 M KOH treatments were 0.7914 and 0.4327 mg g^-1 (increased by 138 and 97%, respectively), because the active sites markedly increased. The ligand exchange, hydrogen bonds, and π-π electron donor-acceptor interactions were the main adsorption mechanisms. The 4 M KOH-modified anthracite could be promising in large-scale applications, both as filter medium and adsorbent for organic contaminants.

Spectroscopic Studies as a Toolbox for Biophysical and Chemical Characterization of Lipid-Based Nanotherapeutics

The goal of this study is to provide tools to minimize trial-and-error in the development of novel lipid-based nanotherapeutics, in favor of a rational design process. For this purpose, we present case-study examples of biophysical assays that help addressing issues of lipid-based nanotherapeutics' profiling and assist in the design of lipid nanocarriers for therapeutic usage. The assays presented are rooted in spectroscopic methods (steady-state and time-resolved fluorescence; UV-Vis derivative spectroscopy; fluorescence anisotropy and fluorescence lifetime image microscopy) and allow accessing physical-chemical interactions between drugs and lipid nanocarriers, as well as studying interactions between lipid-based nanotherapeutics and membranes and/or proteins, as this is a key factor in predicting their therapeutic and off target effects. Derivative spectroscopy revealed Naproxen's high distribution (LogD ≈ 3) in different lipid-based nanocarriers (micelles and unilamellar or multilamellar vesicles) confirming the adequacy of such systems for encapsulating this anti-inflammatory drug. Fluorescence quenching studies revealed that the anti-inflammatory drugs Acemetacin and Indomethacin can reach an inner location at the lipid nanocarrier while being anchored with its carboxylic moiety at the polar headgroup. The least observed quenching effect suggested that Tolmetin is probably located at the polar headgroup region of the lipid nanocarriers and this superficial location may translate in a fast drug release from the nanocarriers. Fluorescent anisotropy measurements indicated that the drugs deeply buried within the lipid nanocarrier where the ones that had a greater fluidizing effect which can also translate in a faster drug release. The drug binding strength to serum albumin was also compared for a free drug (Clonixin) or for the same drug after encapsulation in a lipid nanocarrier DSPC:DODAP (2:1). Under both conditions there is a strong binding to serum albumin, at one binding site, suggesting the need to produce a stealth nanosystem. Finally the cellular uptake of lipid nanocarriers loaded with Daunorubicin was investigated in cancer cells using fluorescence lifetime imaging microscopy. From the images obtained it was possible to conclude that even at short incubation times (15 min) there was a distribution of the drug in the cytoplasm, whereas for longer incubation periods (4 h) the drug has reached the nucleus.

Chromium (VI) biosorption by Saccharomyces cerevisiae subjected to chemical and thermal treatments

The potential of chemically and thermally treated Saccharomyces cerevisiae as biosorbents for chromium (VI) was investigated in this work. The presence of this toxic metal in industrial effluents is harmful to the environment, so, it is important to develop environmental friendly methods for Cr(VI) removal from these effluents. Biosorption using microorganisms such as S. cerevisiae is a viable treatment option because this biomass is easily available as a residue of fermentation industries. In this study, the affecting variables on Cr(VI) biosorption were studied by constructing biosorption isotherms, using lyophilized yeast subjected to chemical and thermal treatments. S. cerevisiae was able to remove 99.66% of Cr(VI) from effluents by biosorption. The significant variables affecting biosorption were pH, initial Cr(VI) concentration, and contact time. The biosorption isotherms were represented by the Freundlich model for the untreated biomass, BET model for the chemically treated biomass, and Langmuir model for the heat-treated biomass. Thermal treatment increased the biosorption affinity of the biomass for chromium, while the chemical treatment facilitated the formation of a multilayer.

Synergistic effect of 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide and titanium oxide on the redox behaviour of flunarizine in solubilized media

Titanium oxide nanoparticles and 1-butyl-2,3-dimethylimidazolium bis (trifluoromethanesulfonyl) imide modified glassy carbon electrode (TiO₂/IL/GCE) has been fabricated for electrochemical sensing of flunarizine (FRH). The electrochemical properties and morphology of the prepared nanocomposite were studied by electrochemical impedance spectroscopy (EIS) and transmission electron microscopy (TEM). The response of the electrochemical sensor was found to be proportional to the concentrations of FRH in the range from 0.5 μgmL^-1 to 16 μgmL^-1. The detection limit obtained was 0.03 μgmL^-1. The proposed method was also applied to the determination of FRH in pharmaceutical formulation and human serum with good recoveries.