Toxic element determination in selected cosmetic products: health risk assessment

The aim of this research was to determine the content of arsenic (As), cadmium (Cd), lead (Pb), and nickel (Ni) in selected lipsticks and face foundations of different price categories and the health risk assessment associated with these toxic elements via dermal and oral exposure. The samples (10 lipstick and 10 face foundations) were purchased from local markets in Belgrade, Serbia. The samples were prepared by acid digestion and analyzed by atomic absorption spectrometry (flame atomization for Cd, Pb, and Ni and electrothermal atomization for As). Arsenic was found in 50% of lipstick samples and in only two face foundation samples with the highest concentration of 0.28 mg/kg in the lipstick sample. Lead concentration was in the range of 1.15 to 5.12 mg/kg in ten samples. Nickel was found in five samples out of 20, with the highest concentration of 4.20 mg/kg. Cadmium was found in only one face foundation sample in the cheaper price range (1.11 mg/kg). The obtained results indicate that concentrations of As, Pb, Cd, and Ni were within the permissible limits according to Serbian legislation. Health risk associated with these elements was assessed as non-carcinogenic and carcinogenic risk. Obtained hazard quotients (HQs) and hazard indexes (HIs) were below 1, indicating the absence of significant non-carcinogenic health risk due to exposure to these toxic elements (TEs). The carcinogenic risk results show that investigated cosmetic products can be considered low-risky due to the possibility of causing malignant disease.

Health risk assessment of heavy metals in soil, plant, and water samples near "Gacko" power plant, in Bosnia and Herzegovina

This study assesses heavy metal content in soil, water, and plant material from sites located around the lignite mine and the power plant "Gacko", Bosnia and Herzegovina. The samples were collected, prepared, and analyzed for heavy metals content using the flame atomic absorption spectrophotometer. Samples were analyzed for cadmium, lead, copper, zinc, manganese, and iron. To identify the relationship among the metals in samples and their possible sources, Pearson's correlation and principal component analysis were performed. Health risk assessment was applied to establish potential health risks posed to humans caused by contaminants in different environmental compartments. The results of our analyses show that most soil samples contain copper, and one of those samples had a copper concentration of more than 70 µg/g, which is a critical upper value for agricultural use. In the soil samples that were analyzed, cadmium was also detected, and its concentration was greater than 2 µg/g. Lead, on the other hand, had a concentration that was higher than the maximum permissible for unpolluted soils in 40% of the soil samples that were analyzed. Lead and cadmium concentrations in surface waters mostly contribute to a non-carcinogenic risk in the scenario of recreational swimming exposure. The presence of Cd, a highly toxic element in water, may be explained by the leaching of artificial fertilizers used in the study area, whereas Pb's origin may be geological. The results of this study recommend routine heavy metal monitoring in samples of soil, water, and plants from the examined area so that, if metal concentrations continue increasing, remedial action should be advised to prevent accumulation in the food chain.

In vitro and in silico study of the biological activity of tetradentate Schiff base copper(II) complexes with ethylenediamine-bridge

The biological activity of six structurally similar tetradentate Schiff base copper(II) complexes, namely [Cu(ethylenediamine-bis-acetylacetonate)] (CuAA) and five derivatives where two methyl groups are replaced by phenyl, (CuPP), CF3 (CuTT) or by mixed groups CH3/CF3 (CuAT), Ph/CF3 (CuPT), and Ph/CH3 (CuAP) has been investigated. The set of antioxidant assays was performed, and the results were expressed as IC₅₀ and EC₅₀ values. The series of complexes showed interesting bioactivity and were investigated for the determination of antioxidant, antifungal, antimicrobial, and cytotoxic activity. A significant antioxidant behavior was exhibited by complex CuAA, greater than Trolox in the Oxygen Radical Absorbance Capacity (ORAC) assay. Antibacterial assay over Gram-positive and Gram-negative pathogenic bacterial strains and some fungal pathogens were studied. Antiproliferative activity of complexes in two human tumor cell lines, breast adenocarcinoma MCF-7, colon adenocarcinoma LS-174, and normal fibroblast cells-MRC-5, examined the effect on cell cycle progression. The significant cytotoxic potential, comparable to cisplatin cytotoxicity, was determined in human breast cancer cell line-MCF-7 with IC₅₀ values being 17.53-31.40 μM and human colon cancer cell line-LS-174 with IC₅₀ values being 15.22-23.92 μM. All tested compounds showed nearly twice more selectivity toward cancer cell lines than normal cells. The interactions of complexes with human serum albumin (HSA), the most prominent protein in plasma, were investigated using spectroscopic fluorescence techniques. The complexes bind to human serum albumin at multiple sites (n = 0.2-1.9), displaying a moderate binding constant K_a = 4.1-12.4 × 10⁴ M^-1. The molecular docking experiment effectively showed complex binding to HSA and DNA molecular fragments.

Surface functional groups and degree of carbonization of selected chars from different processes and feedstock

The knowledge of the structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness test for the analytical methods used in this study. Specific problems connected with the pretreatment of samples and drawbacks of some methods for some types of chars could be identified in an integrated consideration of the results from different methods. None of the spectroscopic methods was found to be suitable for the quality control of all types of chars. The most valuable results were obtained by chemical analysis that, however, required the complete determination of the main elements, including that of oxygen, and of inorganic components for adequate results. The combination of X-ray photoelectron spectroscopy (XPS) and FT-IR spectroscopy allows a rough characterization of surface functional groups, but cannot discriminate aliphatic and aromatic OH groups. FT-IR might be a suitable method for the quality control of biochars made at lower temperature. The results of Raman spectroscopy did not well correlate with the amount of sp2 hybridized carbon determined by XPS. A better correlation of XPS data was found with the electrical polarization determined by the method of spectral induced polarization that was used for the first time in conjunction with extensive analytical characterization.

Voltammetric Determination of Diazepam on Antimony Film Screen- Printed Electrode in Pharmaceutical Formulations

Background:

Diazepam belongs to the group of 1,4-benzodiapines. It is used for the treatment of anxiety, convulsions and as muscle relaxants. The presence of a 4,5-azomethine group enables its electrochemical detection.

Introduction:

A screen-printed electrode modified with antimony film was used for the determination of diazepam in pharmaceutical preparations

Methods:

Electrode modification was done by ex-situ deposition of antimony on a commercially available screen-printed electrode. Parameters affecting the electroanalytical response of the sensor, such as deposition potential, deposition time, and antimony concentration, were examined and optimized. The modified electrode showed enhanced electroactivity for diazepam reduction compared to the unmodified electrode. Under optimal conditions, linear sweep voltammetry was used for the determination of the analyte.

Results:

The sensor showed linear dependence in the range from 0.5 to 10 μmol/L, the correlation coefficient was 0.9992. The limit of detection was 0.33 μmol/L, corresponding limit of quantification was 1.08 μmol/L. Modification enabled determination of diazepam in the presence of oxygen.

Conclusion:

The modified electrode was used for the determination of diazepam in tablets. Results confirmed the applicability of the electrochemical sensor.

Interaction, binding capacity and anticancer properties of N,N′-bis(acetylacetone)-propylenediimine-copper(ii) on colorectal cancer cell line Caco-2

The binding capacity and interaction of N,N′-bis(acetylacetone)propylenediimine-copper(ii) with HSA were systemically investigated in vitro and in silico.

Spectrophotometric determination of caffeine in energy drinks and teas

Introduction: Caffeine is a natural alkaloid, isolated from more than 60 plant species. Over 80% of the world's population consumes caffeine on daily basis through the consumption of coffee, tea, chocolates and, more recently, energy drinks. As a pharmacologically potent substance caffeine is an ingredient of many medicaments available on the pharmaceutical market of Republic of Serbia without a doctor's prescription. Besides that, caffeine acts as a psychoactive stimulant, mild diuretic, and displays an interaction with some medicaments due to the induction of CYP1 and CYP2 isoenzymes. Keeping in mind all of the above, it is necessary to take into account the daily caffeine intake, as well as to control its content in energy drinks. Aim: The aim of this study was spectrophotometric determination of caffeine content in energy drinks and tea, available in markets of the Republic of Serbia. Material and Methods: Caffeine was determinated by UV/VIS spectrophotometry in nine types of energy drinks and eight samples of black and green tea. Results: The results showed that caffeine content in energy drink samples ranged from 26.81 to 35.44 mg/100mL and corresponds to declaration. The caffeine content in tea samples varies with the species (11.27-22.61 mg/100mL for green and 13.85-22.73 mg/100mL for black tea), but also with origin, growth conditions and tea processing. Conclusion: The obtained data suggest that UV/VIS spectrophotometry can be used for routine determination and control of caffeine content in energy drinks and tea. It is important to note that caffeine intake through the usual daily consumption of tea and energy drinks should not have a negative impact on human health, but this alkaloid could be additionally consumed through other sources, which is especially important for certain groups of patients.

Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II)

The porous spinel oxide nanoparticles, MnCo₂O₄, were synthesized by citrate gel combustion technique. Morphology, crystallinity and Co/Mn content of modified electrode was characterized and determined by Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction pattern analysis (XRD), simultaneous thermogravimetry and differential thermal analysis (TG/DTA). Nanoparticles were used for modification of glassy carbon electrode (GCE) and new sensor was applied for simultaneous determination of Pb(II) and Cd(II) ions in water samples with the linear sweep anodic stripping voltammetry (LSASV).The factors such as pH, deposition potential and deposition time are optimized. Under optimal conditions the wide linear concentration range from 0.05 to 40 μmol/dm³was obtained for Pb(II), with limit of detection (LOD) of 8.06 nmol/dm³ and two linear concentration ranges were obtained for Cd(II), from 0.05 to 1.6 μmol/dm³ and from 1.6 to 40 μmol/dm³, with calculated LOD of 7.02 nmol/dm³. The selectivity of the new sensor was investigated in the presence of interfering ions. The sensor is stable and it gave reproducible results. The new sensor was succesfully applied on determination of heavy metals in natural waters.

Selenazolyl-hydrazones as Novel Selective MAO Inhibitors With Antiproliferative and Antioxidant Activities: Experimental and In-silico Studies

The novel approach in the treatment of complex multifactorial diseases, such as neurodegenerative disorders and cancer, requires a development of efficient multi-targeting oriented drugs. Since oxidative stress significantly contributes to the pathogenesis of cancer and neurodegenerative disorders, potential drug candidates should possess good antioxidant properties. Due to promising biological activities shown for structurally related (1,3-thiazol-2-yl)hydrazones, a focused library of 12 structurally related benzylidene-based (1,3-selenazol-2-yl)hydrazones was designed as potential multi-targeting compounds. Monoamine oxidases (MAO) A/B inhibition properties of this class of compounds have been investigated. Surprisingly, the p-nitrophenyl-substituted (1,3-selenazol-2-yl)hydrazone 4 showed MAO B inhibition in a nanomolar concentration range (IC₅₀ = 73 nM). Excellent antioxidant properties were confirmed in a number of different in vitro assays. Antiproliferative activity screening on a panel of six human solid tumor cell lines showed that potencies of some of the investigated compounds was comparable or even better than that of the positive control 5-fluorouracil. In-silico calculations of ADME properties pointed to promising good pharmacokinetic profiles of investigated compounds. Docking studies suggest that some compounds, compared to positive controls, have the ability to strongly interact with targets relevant to cancer such as 5′-nucleotidase, and to neurodegenerative diseases such as the small conductance calcium-activated potassium channel protein 1, in addition to confirmation of inhibitory binding at MAO B.

Development of a Flow Injection System for Differential Pulse Amperometry and Its Application for Diazepam Determination

This work presents the development of a flow injection system for differential pulse amperometry (DPA) for diazepam determination in the presence of oxygen. The thin flow cell consisted of the bare glassy carbon electrode, reference silver/silver chloride, and stainless steel as the auxiliary electrode. Electrochemical reduction of diazepam (DZP) was characterised by cyclic voltammetry. Azomethine reduction peak was used for DZP quantification. The detector response was linear in the range 20-250 µmol/dm³ of diazepam, with a calculated detection limit of 3.83 µg/cm³. Intraday and interday precision were 1.53 and 10.8%, respectively. The method was applied on three beverage samples, energetic drink, and two different beer samples, and obtained recoveries were from 93.65 up to 104.96%. The throughoutput of the method was up to 90 analyses per hour.

Assessment of non-steroidal anti-inflammatory and analgesic pharmaceuticals in seawaters of North of Portugal: occurrence and environmental risk

The occurrence of seven pharmaceuticals and two metabolites belonging to non-steroidal anti-inflammatory drugs and analgesics therapeutic classes was studied in seawaters. A total of 101 samples covering fourteen beaches and five cities were evaluated in order to assess the spatial distribution of pharmaceuticals among north Portuguese coast. Seawaters were selected in order to embrace different bathing water quality (excellent, good and sufficient). Acetaminophen, ketoprofen and the metabolite hydroxyibuprofen were detected in all the seawater samples at maximum concentrations of 584, 89.7 and 287 ng L(-1), respectively. Carboxyibuprofen had the highest seawater concentration (1227 ng L(-1)). The temporal distribution of the selected pharmaceuticals during the bathing season showed that, in general, higher concentrations were detected in August and September. The environmental risk posed by the pharmaceuticals detected in seawaters towards different trophic levels (fish, daphnids and algae) was also assessed. Only diclofenac showed hazard quotients above one for fish, representing a potential risk for aquatic organisms. These results were observed in seawaters classified as excellent bathing water. Additional data is needed in order to support the identification and prioritization of risks posed by pharmaceuticals in marine environment.

Anthelmintic activity in vivo of epiisopiloturine against juvenile and adult worms of Schistosoma mansoni

Schistosomiasis is a serious disease currently estimated to affect more that 207 million people worldwide. Due to the intensive use of praziquantel, there is increasing concern about the development of drug-resistant strains. Therefore, it is necessary to search for and investigate new potential schistosomicidal compounds. This work reports the in vivo effect of the alkaloid epiisopiloturine (EPI) against adults and juvenile worms of Schistosoma mansoni. EPI was first purified its thermal behavior and theoretical solubility parameters charaterised. In the experiment, mice were treated with EPI over the 21 days post-infection with the doses of 40 and 200 mg/kg, and 45 days post-infection with single doses of 40, 100 and 300 mg/kg. The treatment with EPI at 40 mg/kg was more effective in adult worms when compared with doses of 100 and 300 mg/kg. The treatment with 40 mg/kg in adult worms reduced parasite burden significantly, lead to reduction in hepatosplenomegaly, reduced the egg burden in faeces, and decreased granuloma diameter. Scanning electron microscopy revealed morphological changes to the parasite tegument after treatment, including the loss of important features. Additionally, the in vivo treatment against juvenile with 40 mg/kg showed a reduction of the total worm burden of 50.2%. Histopathological studies were performed on liver, spleen, lung, kidney and brain and EPI was shown to have a DL50 of 8000 mg/kg. Therefore EPI shows potential to be used in schistosomiasis treatment. This is the first time that schistosomicidal in vivo activity of EPI has been reported.