Determination of antioxidant, antimicrobial and antitumor activity of bryophytes from Mount Ida (Canakkale, Turkey)

395-401In this study, active components of bryophytes were extracted from the samples collected from Mount Ida (Canakkale- Turkey). Three different extraction methods (Soxhlet, supercritical fluid extraction-SFE, Soxhlet after SFE) were employed for 2016 samples while direct Soxhlet extraction was carried out for 2017 samples using methanol as extracting solvent. Initially, antioxidant activity tests of the crude extracts were performed for all the samples. Antioxidant properties were determined to be fairly weak or moderate in the majority of the species studied. Marchantia polymorpha (T1), a liverwort, showed high extraction yield and antioxidant activity. Similarly, high activity was detected in Hypnum cupressiforme (T9) and Neckera complanata (T10) species. The antioxidant capacity of the tested species often sheds light on other activities. Antimicrobial properties were also tested for all extracts obtained in 2017. Thuidium tamariscinum (T8) was positive against Acinetobacter haemolyticus ATCC 19002 bactericin; T1 and Isothceum myurum (T11) were positive against Bacillus subtilis TCC6633 bacteria and all other species were negative. Following these results, we have concentrated on the most active species and carried out antitumoral tests. Again, fractioned polar isolate of T1 was the only antiproliferative species against HeLa and A549 lung cancer cells

Fabrication of PAMP/Au and GO/PAMP/Au nanosensors for electrochemical detection of paracetamol in pharmaceutical preparations

This paper reports on the modification of Pencil Graphite Electrode (PGE) surface with the poly(2-amino-4-methylphenol)/gold (PAMP/Au) and graphene oxide/poly(2-amino-4-methylphenol)/gold (GO/PAMP/Au) nanocomposites, in two steps. The first step is based on the one-pot preparation of composites by template-free chemical oxidation process. In the second step, composites are deposited at PGE surface by electro-oxidation process. Both nanocomposites and modified PGE surfaces are characterized by X-Ray Diffraction method (XRD), Scanning Electron Microscopy (SEM), EDAX, and CV analyses. The electrochemical performances of modified electrodes (abbreviated as PAMP/Au-PGE and GO/PAMP/Au-PGE) were investigated. The limit of detection values for PGE, PAMP/Au-PGE, and GO/PAMP/Au-PGE were found to be 2.74 × 10–6, 5.29 × 10–7, and 2.91 × 10–8 mol/dm3, respectively. The limit of quantification values were determined as 9.14 × 10–6, 1.76 × 10–6, and 9.69 × 10–8 mol/dm3 for PGE, PAMP/Au-PGE, and GO/PAMP/Au-PGE, respectively

Investigation of Competitive and Noncompetitive Adsorption of Some Heavy Metals Ions on Leucodon sciuroides (Hedw.) Schwägr

Heavy metals are an important pollutant group. Adsorption is one of the methods used to remove heavy metals from the environment. Mosses were preferred as bio-indicators because they have the capacity to accumulate many elements by their high surface-to-volume ratio. Leucodon sciuroides (Hedw.) Schwägr. (LS) are mosses that play an important part of the ecosystem and are collected from the Ida Mountain (Kazdag) region of Çanakkale (Turkey). For the purpose of determining the adsorption capacity of heavy metal ion (Pb2+, Cd2+, Co2+, Ni2+, Zn2+, and Cu2+) analysis conditions, pH, contact time, and adsorbent amounts were determined and the maximum adsorption capacity was calculated with the help of the relevant isotherms. Heavy metal concentrations were determined by inductively coupled plasma-mass spectrometry. It was determined that the optimum adsorption for mosses was 30 min at pH = 6.0 (the pH at which maximum adsorption occurs). The adsorption event shows that some divalent cations fit the Freundlich isotherm and some fit the Langmuir isotherm model. A pseudo-second-order reaction best fits the kinetic data for metal ions. Among the six metal ions studied, the highest adsorption was observed in Pb2+ and Cu2+ cations. According to the competitive adsorption results, the moss has a great advantage in determining the Pb2+ and Cu2+ cations industrially as well as other metals and in removing other metal impurities from the environment. Also, LS is exploited as a biosorbent to remove metal ions from aqueous solutions and can be used as a biomarker

Electrochemical and liquid chromatographic analysis of triamcinolone acetonide in pharmaceutical formulations

Electrochemical reduction of triamcinolone acetonide on pencil graphite electrode surface was firstly investigated by cyclic voltammetry (CV). The dependence of cathodic peak current and peak potential on different pH medium and scan rate were investigated. The adsorption controlled nature of the peak was achieved. During pH optimization, 0.067 M Phosphate (pH 4.50 to pH 7.50), 0.2 M Acetate (pH 3.50 to 5.50) and 0.04 M Britton Robinson (BR; pH 2.00 to 12.00) buffers were employed as supporting electrolytes. Scan rate optimization was investigated in the range 25-1000 mVs-1 (vs. Ag/AgCl). Maximum peak current was observed in the 0.04 M BR buffer (pH 3.50). Peak current increases and shifts to more cathodic values with the increasing scan rate. Curve of logarithm of peak current (log I) versus logarithm of scan rate (log v) showed linear regression with the equation log(Ip/µA) = 0.8395 log(v/mVs-1)-0.8386 and correlation coefficient (R2: 0.9761). This indicated that slope of the logv-logI curve is close to 1.0 and the cathodic electrode reaction was adsorption controlled, as desirable. The linear range was 1×10-7-5×10-5 M, sensitivity was 1,3347 µA M-1, Limit of detection (LOD) and Limit of quantification (LOQ) were 3.18×10-8 M and 1.00×10-7 M, respectively. HPLC-PDA analysis were performed with H2O:MeOH (28:72, v/v) as mobile phases A and B at a flow rate of 1mL/min at 242nm. Method validation studies were conducted in accordance with ICH Q2(R1) guideline and corresponding results were summarized in tables. HPLC-PDA method displayed linearity in 0.1-50µg/mL (2.3×10-7-1.15×10-4 M) concentration range with LOD and LOQ values as 3.992×10-8 and 1.29×10-7M, respectively

A novel electrochemical biosensor based on palladium nanoparticles decorated on reduced graphene oxide-polyaminophenol matrix for the detection and discrimination of mitomycin C-DNA and acyclovir-DNA interaction

Both the design of molecules that will interact specifically with DNA and the determination of the mechanism of action of this drug on DNA are important as they allow the control of gene expression. In particular, rapid and precise analysis of this type of interaction is a vital element for pharmaceutical studies. In the present study, a novel reduced graphene oxide/ palladium nanoparticles/ poly(2-amino-4-chlorophenol) (rGO/Pd@PACP) nanocomposite was synthesized by chemical process to modify pencil graphite electrode (PGE) surface. Here, the performance of the newly developed nanomaterial-based biosensor for drug-DNA interaction analysis has been demonstrated. For this purpose, it was determined whether this system, which was developed by selecting a drug molecule (Mitomycin C; MC) known to interact with DNA and a drug molecule (Acyclovir; ACY) that does not interact with DNA, performs a reliable/accurate analysis. Here, ACY was used as a negative control. Compared to bare PGE, the rGO/Pd@PACP nanomaterial modified sensor exhibited 17 times higher sensitivity performance in terms of guanine oxidation signal measured by differential pulse voltammetry (DPV). Moreover, the developed nanobiosensor system provided a highly specific determination between the anticancer drug MC and ACY by discrimination the interactiBoth the design of molecules that will interact specifically with DNA and the determination of the mechanism of action of this drug on DNA are important as they allow the control of gene expression. In particular, rapid and precise analysis of this type of interaction is a vital element for pharmaceutical studies. In the present study, a novel reduced graphene oxide/ palladium nanoparticles/ poly(2-amino-4-chlorophenol) (rGO/Pd@PACP) nanocomposite was synthesized by chemical process to modify pencil graphite electrode (PGE) surface. Here, the performance of the newly developed nanomaterial-based biosensor for drug-DNA interaction analysis has been demonstrated. For this purpose, it was determined whether this system, which was developed by selecting a drug molecule (Mitomycin C; MC) known to interact with DNA and a drug molecule (Acyclovir; ACY) that does not interact with DNA, performs a reliable/accurate analysis. Here, ACY was used as a negative control. Compared to bare PGE, the rGO/Pd@PACP nanomaterial modified sensor exhibited 17 times higher sensitivity performance in terms of guanine oxidation signal measured by differential pulse voltammetry (DPV). Moreover, the developed nanobiosensor system provided a highly specific determination between the anticancer drug MC and ACY by discrimination the interactions of these drugs with double-stranded DNA (dsDNA). ACY was also preferred in studies for the optimization of the new nanobiosensor developed. ACY was detected in a concentration as low as 0.0513 μM (51.3 nM) (LOD), and limit of quantification (LOQ) was 0.1711 μM with a linear range from 0.1 to 0.5 μM. ons of these drugs with double-stranded DNA (dsDNA). ACY was also preferred in studies for the optimization of the new nanobiosensor developed. ACY was detected in a concentration as low as 0.0513 μM (51.3 nM) (LOD), and limit of quantification (LOQ) was 0.1711 μM with a linear range from 0.1 to 0.5 μM