Palladium(II) Schiff base complex arrests cell cycle at early stages, induces apoptosis, and reduces Ehrlich solid tumor burden: a new candidate for tumor therapy.

Although many cancer drugs are clinically approved, they still suffer from no adequate efficiency or drug resistance, or bad side effects. Therefore, developing safer alternatives of competitive efficiency is needed. This study aimed to investigate, for the first time, the antitumor and apoptotic activities of palladium(II) 2-hydroxyimino-3-(2-hydrazonopyridyl)-butane complex against Ehrlich carcinoma. In vitro, EAC cells were incubated with the complex, and the cells' viability, caspase 8 activity, and cell cycle changes were evaluated. In vivo, eighty adult female Swiss albino mice were distributed randomly in the following groups (n = 10): Normal, EAC, EAC + Cisplatin, and four groups EAC + Complex as well as Normal + Complex. Bodyweight changes were noted. On day 22 mice were sacrificed. Tumors' volume and weight were recorded. Blood picture was routinely investigated. The median survival time (MST) and percent increase in life span (%ILS) were monitored. In vitro, the complex reduced the %viable EAC cells, increased caspase 8 activity, arrested cell cycle at G0/G1, and reduced G2(M) population indicating antiproliferative and antitumor activities via inducing apoptosis. Treatment with the complex in a dose-dependent mode significantly decreased tumor volume and weight, extended the MST and the %ILS, increased mice body weight gain, and improved the blood indexes. Treatment of EAC-bearing mice with the complex highest dose showed more desirable outcomes than treatment with cisplatin. The Normal + Complex group showed no pathological changes indicating safety. In conclusion, our outcomes recommend the Pd(II) complex as a new optimistic candidate for tumor therapy after further studies for validation.

Schiff base 4-ethyl-1-(pyridin-2-yl) thiosemicarbazide up-regulates the antioxidant status and inhibits the progression of Ehrlich solid tumor in mice.

Cisplatin is an approved cancer therapeutic drug used to treat many solid tumors but its accumulation in the kidney, which causes nephrotoxicity, limits its clinical use. Therefore, investigators seek new alternatives to cisplatin that may be more effective and/or safer. Thiosemicarbazides are of great significance due to their expected biological activity including anticancer activities. The aim of this work is the study of the antitumor effect of Schiff base 4-ethyl-1-(pyridin-2-yl) thiosemicarbazide (HEPTS) on Ehrlich solid tumor-bearing mice in comparison to cancer therapeutic drug cisplatin. The experiment was run using sixty adult female Swiss albino mice. Mice were allocated into six groups (n = 10 mice). Healthy control, EAC control (untreated tumor), EAC + cisplatin, EAC + HEPTS, Healthy + HEPTS, and Healthy + solvent. After scarification, blood samples, liver organs, and solid tumors were collected. Tumor weights and volumes were registered. The concentrations of malondialdehyde (MDA), reduced glutathione (GSH), SOD, catalase (CAT), total antioxidant capacity (TAC), nitric oxide (NO), uric acid, creatinine, and urea were assessed. Median survival time (MST) and the percentage increase in lifespan (%ILS) were also calculated. Treatment of tumorized mice with HEPTS significantly reduced both tumor volume and weight while it significantly increased the MST, antioxidant marks and prolonged the %ILS. It also, significantly reduced MAD, creatinine, urea, uric acid, and NO levels. Compared to cisplatin, HEPTS effects were better. Our results recommend HEPTS as one of the probable cisplatin-alternatives for tumor treatment after more validation.

Nickel(II) diacetyl monoxime-2-pyridyl hydrazone complex can inhibit Ehrlich solid tumor growth in mice: A potential new antitumor drug.

The chief chemotherapeutic drug, cisplatin had common bad effects such as nephrotoxicity, ototoxicity and bone marrow depression. This led us to develop a new potential anticancer drug based on nickel metal ion that may be less toxic. Nickel(II) diacetyl monoxime-2-pyridyl hydrazone complex cytoprotective effect, superoxide dismutase (SOD)-like activity and anticancer activities were studied. In vitro, the complex showed SOD-like activity of 86.62%. It was capable to kill 90.2% of Ehrlich ascites carcinoma (EAC) cells and to protect 92.48% of human RBCs. In vivo, the complex lowered the tumor burden markedly in a concentration-dependent manner. Noticeably, solid tumor growth was suppressed; tumor volume and weight were reduced and mice life span was lengthened. The hematological indices were improved, catalase activity was re-elevated and malondialdehyde (MDA) level was reversed towards normal. Nucleic acids, cholesterol, triglycerides, liver enzymes, urea and creatinine contents were reduced to near normal ranges. Glutathione (GSH), SOD, albumin and total protein levels were increased. In conclusion, our results revealed that the complex has the ability to suppress Ehrlich solid tumor growth in mice with minimal side effects. This may possibly via its redox activity. Surprisingly, nickel complex antitumor activities were more potent than those of cisplatin.

Regression of murine Ehrlich ascites carcinoma using synthesized cobalt complex.

Cisplatin as a chief chemotherapy has nephro-toxicity and so we have tried to develop a novel antitumor drug based on a combination of cobalt metal ion with an organic moiety. The antitumor activity of the complex was tested in vitro and in vivo against murine Ehrlich ascites carcinoma (EAC). Antioxidant capacity and nucleic acids content were determined. Cobalt(ii) diacetyl monoxime-2-hydrazinopyridine complex significantly diminished tumor load. It decreased the tumor proliferation rate and obviously increased the life span of EAC-bearing mice. It reversed the haematological parameters back towards normal, reduced liver enzymes and urea, and increased albumin and total protein. Antioxidant parameters levels were reversed towards normal. An assessment was conducted by comparing these results with those obtained using the standard drug, cisplatin. The results suggest that the cobalt complex can be considered as a potent anticancer agent as it showed appreciable antitumor activity in EAC-bearing mice that was almost analogous to that of the reference standard, cisplatin.

Solid Phase Extraction and Preconcentration of Trace Gallium, Indium, and Thallium Using New Modified Amino Silica.

Amino silica gel functionalized with 2-hydroxy-5 -(2-hydroxybenzylideneamino)benzoic acid was synthesized, characterized and used as adsorbent for the removal of Ga3+, In3+ and Tl3+ from aqueous solution prior to their determination by flame atomic absorption spectrometry. Experimental parameters that affect the separation process were investigated in both batch and column modes. The maximum adsorption capacities of the sorbent are 61.7 mg g-1, 81.3 mg g-1 and 133.0 mg g-1 for Ga3+, In3+ and Tl3+, respectively. The preconcentration factor is 200 and the limits of detection of Ga3+, In3+ and Tl3+ are 4.10 µg L-1, 1.55 µg L-1 and 1.21 µg L-1, respectively. Interference by Al3+ can be masked by the addition of F-; and that of Fe3+ by its reduction to Fe2+ using 10% ascorbic acid. The method was successfully applied for the determination of these ions in water, sediments and liquid crystal display samples.

Mixed Micelle-mediated Extraction and Separation of Scandium from Yttrium and Some Lanthanide Ions.

A simple mixed-micelle mediated extraction was elaborated for the preconcentration and determination of scandium(III) by inductively coupled plasma optical emission spectrometry. Scandium(III) was complexed with Alizarin Red S and cetyltrimethylammonium bromide at pH 3 to form hydrophobic chelates, which could be extracted with Triton X-114 at room temperature (25°C) in the presence of KI as a salting-out electrolyte. The main parameters of the extraction procedure were investigated in regard to the extraction efficiency of scandium(III). Under the optimum conditions, a linear range of 0.5 - 150 ng mL(-1) and a detection limit of 0.2 ng mL(-1), along with a preconcentration factor of 100, were achieved. Furthermore, the interference of diverse ions accompanying scandium(III) was extensively studied. The obtained results indicate the high selectivity of the proposed procedure. The accuracy of the procedure was verified through recovery experiments on spiked water samples and synthetic mixtures. The procedure was successfully applied to a scandium(III) determination in clay samples.

Application of Cloud Point Extraction for Cadmium in Biological Samples of Occupationally Exposed Workers: Relation Between Cadmium Exposure and Renal Lesion.

Cadmium (Cd) level in blood and urine of soldering iron workers (n=49) and 41 matched healthy controls has been assessed. Cloud point extraction was employed for preconcentration of Cd. The Cd ions formed hydrophobic complex with 9,10-phenanthraquinone monoethyl thiosemicarbazone that was extracted by surfactant-rich phases in the nonionic surfactant Triton X-114. The surfactant-rich phase was diluted with 1 M HNO3 in methanol prior to its analysis by graphite furnace atomic absorption spectrometry. The parameters affecting the extraction efficiency of the proposed method, such as solution pH, amount of complexing agent, surfactant concentration, temperature, and incubation time, were optimized. Under the optimum experimental conditions, the detection limit and the enrichment factor were 0.04 µg L(-1) and 61, respectively. Relative standard deviation of 10 µg L(-1) Cd was less than 3.0%. The accuracy of the method was examined by analysis of certified reference materials. It was observed that soldering iron workers are liable to Cd overload as indicated by higher levels of Cd in blood and urine when compared with the controls. This exposure may lead to kidney damage indicated by elevation of urinary excretion of both N-acetyl-ß-D-glucosaminidase and ß2-microglobulin.

Study of organically-modified montmorillonite clay for the removal of copper(II).

2-Oxyhydrazino-N-(2-methylen-yl-hydroxyphenyl)pyridinium (OMHP) ion was immobilized onto Na-montmorillonite clay (MMT). The modified clay (OMHP-MMT) was used for the removal of Cu(II). Experiments were carried out as a function of solution pH, stirring time, effect of some common ions and eluent type, concentration and volume. MMT, OMHP-MMT, and OMHP-MMT-loaded Cu(II) were characterized by X-ray diffractometry, electronic and infrared spectra, and elemental and thermogravimetric analyses. OMHP is suggested to be intercalated into MMT parallel to the aluminosilicate layers, with a capacity of 56.4 mEq/100g. OMHP-MMT shows good stability in 0.1-1 mol L(-1) hydrochloric or nitric acids, ammonia hydroxide, concentrated Na(+), K(+), NH(4)(+), Cl(-) or SO(4)(2-). It shows good removal efficiency and selectivity towards Cu(II) at pH 3.0-8.0 and stirring time 10 min with an removal capacity of 119 mEq/100g. Most common ions do not interfere with the removal process except Fe(3+). Extracted Cu(II) could be quantitatively recovered by 10 mL 1% thiourea in 0.1 mol L(-1) HCl with 100-fold preconcentration factor. OMHP-MMT was successfully applied to recover Cu(II) from different samples.

Immobilization of methylene blue onto bentonite and its application in the extraction of mercury (II).

Methylene blue was immobilized onto bentonite (BNT). The modified clay (MB-BNT) was used to extract Hg(2+) at pH 6.0 yielding Hg-MB-BNT. BNT, MB-BNT and Hg-MB-BNT were characterized by X-ray diffractometry, infrared spectra, and elemental and thermogravimetric analyses. MB is suggested to be intercalated into the major phase of BNT; montmorillonite mineral (MMT), lying parallel to the aluminosilicate layers, with a capacity of 36 mequiv./100g. MB-BNT shows good stability in 0.1-1M hydrochloric or nitric acids, ammonium hydroxide, and concentrated Na(+), K(+) or NH(4)(+) chlorides or iodides. It shows good selectivity towards Hg(2+) with an extraction capacity of 37 mequiv./100g in the presence of I(-) giving rise to a ratio of MB/Hg(2+)/I(-) 1:1:3 in the clay phase. Extracted Hg(2+) could be quantitatively recovered by ammonia buffer at pH 8.5. MB-BNT was successfully applied to recover Hg(2+) from spiked natural water and cinnabar mineral samples using the optimum conditions; pH 6.0, time of stirring 10 min and 10 mL of 0.05 M NH(4)Cl/NH(4)OH at pH 8.5 as eluent.

Silica glass modified with flavonoid derivatives for preconcentration of some toxic metal ions in water samples and their determination with ICP-MS.

Quercetin (3,3',4',5,7-pentahydroxyflavone) chemically bonded through pyran rearrangement on modified controlled pore silica glass (QCPSG) with a capacity 0.213 mmol/g was used for solid phase extraction of some toxic metal and metalloid ions. The newly designed QCPSG quantitatively sorbs As(V), Cd(II), Hg(II), and Pb(II) at the pH range 7.5-8.5 after 10 min of stirring. HCl (1 mol L(-1)) instantaneously elutes all the metal ions. The sorption capacity of the ion collector is 0.42, 0.46, 0.53, and 0.49 mmol g(-1) for As(V), Cd(II), Hg(II), and Pb(II), respectively, whereas the preconcentration factor is 200. The effect of NaCl, Na2SO4, NaF, NaBr, Na3PO4, and other interfering salts on the sorption of metal ions (50 microg L(-1)) was reported. Analytical detection limits of As(V), Cd(II), Hg(II), and Pb(II) were 4.18, 2.44, 15.86, and 25.00 pg mL(-1), respectively. QCPSG was used in the separation of the investigated metal ions from some natural water samples collected from diverse origins followed by determination by inductively coupled plasma-mass spectrometry. The data were compared with those obtained by the standard methods of determination using atomic absorption (hydride generation, HGAAS and after solvent extraction with ammonium pyrolidine dithiocarbamate/methyl isobutyl ketone). The suggested solid phase extraction method was found accurate with no random error.

Synthesis and characterisation of morin-functionalised silica gel for the enrichment of some precious metal ions.

Silica gel was firstly functionalised with aminopropyltrimethoxysilane obtaining the aminopropylsilica gel (APSG). The APSG was reacted subsequently with morin yielding morin-bonded silica gel (morin-APSG). The structure was investigated and confirmed by elemental and thermogravimetric analyses, IR and (13)C NMR spectral studies. Morin-APSG was found to be highly stable in common organic solvents, acidic medium (<2molL(-1) HCl, HNO(3)) or alkaline medium up to pH 8. The separation and preconcentration of Ag(I), Au(III), Pd(II), Pt(II) and Rh(III) from aqueous medium using morin-APSG was studied. The optimum pH values for the separation of Ag(I), Au(III), Pd(II), Pt(II) and Rh(III) on the sorbent are 5.7, 2.2, 3.7, 3.7 and 6.8, giving rise to separation efficiencies of 43.9, 85.9, 97.7, 60.9 and 91.0%, respectively, where the activity was found to be >90% in the presence of acetate ion. The ion sorption capacity of morin-APSG towards Cu(II) at pH 5.5 was found to be 0.249mmolg(-1) where the sorption capacities of Ag(I) and Pd(II) were 0.087 and 0.121mmolg(-1) and 0.222 and 0.241mmolg(-1) at pH 2.2 and 5.7, respectively. This indicates a 1:1 and 1:2 morin/metal ratios at pH 2.2 and 5.7, respectively. Complete elution of the sorbed metal ions was carried out using 10mL (0.5molL(-1) HCl+0.01molL(-1) thiourea) in case of Au(III), Pd(II), Pt(II) and Rh(III) and 10mL 0.5molL(-1) HNO(3) in case of Ag(I). Morin-APSG was successfully employed in the separation and preconcentration of the investigated precious metal ions from some spiking water samples yielding 100-folds concentration factor. The relative standard deviation (R.S.D.) and the T-test (|t|(1)) were calculated.

A new selective chromogenic reagent for the spectrophotometric determination of thallium(I) and (III) and its separation using flotation and the solid-phase extraction on polyurethane foam.

A new sensitive chromogenic reagent, 9,10-phenanthaquinone monoethylthiosemicarbazone (PET), has been synthesized and used in the spectrophotometric determination of Tl(III). In HNO3, H2SO4 or H3PO4 acids, PET can react immediately at room temperature with Tl(III) to form a red 2:1 complex with a maximum absorption at 516 nm. The different analytical parameters affecting the extraction and determination processes have been examined. The calibration curve was found to be linear over the range 0.2-10 microg cm(-3) with a molar absorptivity of 2.2 x 10(4) dm3 mol(-1) cm(-1). Sandell's sensitivity was found to be 0.0093 microg cm(-2). No interference from macroamounts of foreign ions was detected, except for Pd(II). However, Pd(II) does not affect the determination process, because its complex with PET has its lambda(max) at 625 nm. The proposed method has been applied to the determination of Tl(I and III) in synthetic and natural samples after separation by flotation (in oleic acid/kerosene) and solid-phase extraction (on polyurethane foam) techniques. The two methods were found to be accurate and not subject to random error, but solid-phase extraction was preferred because it is cheap, simpler and there is no contamination risk coming from flotation reagents.

Controlled-pore silica glass modified with N-propylsalicylaldimine for the separation and preconcentration of trace Al(III), Ag(I) and Hg(II) in water samples.

Controlled-pore silica glass modified with N-propylsalicylaldimine (SCPSG) has been investigated as a surface-active matrix for the separation of some metal ions. The porous silica glass base was confirmed to have better stability towards hydrolysis in aqueous solution buffered at pH=9 in comparison to silica gel, which showed twice the surface area of controlled-pore silica glass. The different analytical parameters affecting the batch mode separation and preconcentration of trace Al(II), Ag(I) and Hg(II) in environmental samples using SCPSG, prior to their determination using inductively coupled plasma mass spectrometry (ICP-MS), were studied. The optimum conditions are pH 9.0 +/- 0.1, time of stirring 30 min and the eluent concentration 0.5 mol dm(-3) HNO3. The ion-exchange capacity of SCPSG with respect to Al(III), Ag(I) and Hg(II) was 0.27, 0.18 and 0.23 mmol g(-1), respectively. The recovery values for the metal ions were 96.8 +/- 0.86, 98.1 +/- 0.60 and 96.2 +/- 1.06%, and the analytical detection limits were 26.1, 1.49 and 0.44 pg cm(-3), respectively, for a preconcentration factor of 100. The method has been applied to the determination of the investigated metal ions in natural water samples as well as certified and reported samples and the results were found to be accurate.