Spectroscopic characterizations and biological studies on newly synthesized Cu2+ and Zn2+ complexes of first and second generation dendrimers

Refat, Moamen S.; El‐Deen, Ibrahim M.; Grabchev, Ivo; Anwer, Zeinab M.; El-Ghol, Samir

doi:10.1016/j.saa.2008.11.024

Cited by 22 publications

(5 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…C. The thermal decomposition of the [Zn(GMFX)(Bipy)(H 2 O) 2 ](CH 3 COO) 2 ÁH 2 O complex takes place in three steps. The first stage of decomposition occurs with a maximum temperature value of 54°C and is accompanied by a weight loss of 2.50 %, corresponding to loss of crystallization water molecule [45]. The second decomposition step occurs with two maxima at 154 and 256°C, with a weight loss of 24.64 %, corresponding to loss of coordinated water and 2,2 0 -bipyridine molecules.…”

Section: Synthesis Spectroscopic Characterization Thermal…mentioning

confidence: 99%

Synthesis, spectroscopic characterization, thermal stability and biological studies of mixed ligand complexes of gemifloxacin drug and 2,2′-bipyridine with some transition metals

2015

View full text Add to dashboard Cite

The mixed ligand Zn(II), Zr(IV), Pd(II), Ce(IV), Th(IV), and U(VI) complexes of gemifloxacin and N-donor 2,2 0 -bipyridine have been prepared. These complexes have been characterized by elemental, infrared (IR), ultraviolet-visible (UV-Vis), 1 H nuclear magnetic resonance (NMR), mass spectroscopy, thermal, molar conductance and magnetic susceptibility analyses. The infrared spectra indicate that gemifloxacin acts as a bidentate deprotonated ligand bound to the metal through the pyridone oxygen and one carboxylate oxygen, whereas the 2,2 0 -bipyridine coordinates through the two nitrogen atoms. The central metal in each complex is six-coordinate and a slightly distorted octahedral geometry is proposed. The calculated bond length and force constant, F(U=O), in the uranyl complex are 1.751 Å and 641.04 N m -1 , respectively. The thermodynamic parameters are calculated from the thermal analysis curves using the Coats-Redfern and HorowitzMetzger methods. The antibacterial and antifungal activities of the ligand, metal salt and metal complexes have been tested. The data show that the complexes exhibit significant action against some of the four bacterial species but no effect on two species of fungi compared with gemifloxacin. The antitumor activity of the ligands and their complexes has been evaluated against breast (MCF-7) and colon (HCT-116) cancer cells.

show abstract

Section: Synthesis Spectroscopic Characterization Thermal…mentioning

confidence: 99%

Synthesis, spectroscopic characterization, thermal stability and biological studies of mixed ligand complexes of gemifloxacin drug and 2,2′-bipyridine with some transition metals

2015

View full text Add to dashboard Cite

show abstract

“…Dijkgraaf et al ( 2007 ) used this approach to synthesize dendrimers conjoined with RGD peptides and DOTA, for use in tumor imaging after complexation with radionuclides such as 111 In or 64 Cu. Some dendritic copper complexes were tested for antimicrobial activity by Refat et al ( 2009 ) and showed moderate strength of action on selected microorganisms. Poly(amidoamine)-Schiff base dendrimers synthesized by Zhao et al ( 2010 ) form multinuclear complexes with CuCl 2 , which show good antiproliferative activity against MOLT-4 leukemia and cisplatin resistant MCF-7 breast cancer cells.…”

Section: Copper In Nanomedicinementioning

confidence: 99%

Development of copper based drugs, radiopharmaceuticals and medical materials

et al. 2012

View full text Add to dashboard Cite

Copper is one of the most interesting elements for various biomedical applications. Copper compounds show vast array of biological actions, including anti-inflammatory, anti-proliferative, biocidal and other. It also offers a selection of radioisotopes, suitable for nuclear imaging and radiotherapy. Quick progress in nanotechnology opened new possibilities for design of copper based drugs and medical materials. To date, copper has not found many uses in medicine, but number of ongoing research, as well as preclinical and clinical studies, will most likely lead to many novel applications of copper in the near future.

show abstract

“…15,17,19,21 The applications of such metallodendrimers comprise different fields; for instance, some PPI dendrimers coordinate metal ions such as Fe 3+ , Co 2+ , Cu 2+ , VO 2+ , etc., and act as catalysts 27 in epoxidation of cyclohexene, or some complexes of Cu II , Zn II and Ni II of different generations of DAB 6 have been used as support materials for metal nanoparticles in water. In the biomedical field, some metallodendrimers present interesting activities, such as antibacterial properties (Cu II and Zn II complexes of PPI dendrimers 28 comprising 1,8-naphthalimide units on the periphery) or antitumoral activity (tetranuclear platinum functionalized metallodendrimer 29 DAB(PA-tPt-Cl) 4 based on the polyamino G1 PPI dendrimer or sodium carboxylate generation 3.5 PAMAM, which coordinates cisplatin). 30 The EPR technique has proved very valuable in providing unique information on the complexation ability of different dendrimers towards Cu 2+ and Mn 2+ .…”

Section: Introductionmentioning

confidence: 99%

Anionic sulfonated and carboxylated PPI dendrimers with the EDA core: synthesis and characterization of selective metal complexing agents

García‐Gallego¹,

Cangiotti²,

Fiorani³

et al. 2013

Dalton Trans.

View full text Add to dashboard Cite

Herein we describe the synthesis and characterization of new sulfonated and carboxylated poly(propyleneimino) (PPI) dendrimers with the ethylenediamino (EDA) core, at generations 1, 2 and 3. By means of UV-Vis and EPR spectroscopy, using Cu(2+) as a probe, we concluded that these dendrimers show a specific pattern in the coordination of metal ions. In agreement with the UV-Vis studies, EPR spectra of carboxylated compounds are constituted by 3 different signals which appear and then disappear with increasing copper concentration, corresponding to the saturation of different copper complexation sites. At the lowest copper concentration up to a 1:1 molar ratio between Cu(II) and the dendrimer, the spectrum is characteristic of a CuN2O2 coordination at the core of the dendrimer. The spectrum appearing at higher Cu(II) concentrations indicates a peripheral location of the ions coordinating one nitrogen and 3 oxygen atoms in a square planar geometry in restricted mobility conditions. For the highest concentrations tested, copper ions are confined at the external dendrimer surface with CuO4 coordination. For sulfonate systems, the EPR results are in line with a weaker interaction of Cu(II) with the nitrogen sites and a stronger interaction with the oxygen (SO3(-)) groups with respect to the interactions measured by EPR for carboxylate systems.

show abstract

Spectroscopic characterizations and biological studies on newly synthesized Cu2+ and Zn2+ complexes of first and second generation dendrimers

Cited by 22 publications

References 35 publications

Synthesis, spectroscopic characterization, thermal stability and biological studies of mixed ligand complexes of gemifloxacin drug and 2,2′-bipyridine with some transition metals

Synthesis, spectroscopic characterization, thermal stability and biological studies of mixed ligand complexes of gemifloxacin drug and 2,2′-bipyridine with some transition metals

Development of copper based drugs, radiopharmaceuticals and medical materials

Anionic sulfonated and carboxylated PPI dendrimers with the EDA core: synthesis and characterization of selective metal complexing agents

Contact Info

Product

Resources

About