Synergistic effect of perchlorate ions and acetonitrile medium explored for extension in copper redoximetry

Rizvi, Masood Ahmad; Akhoon, Showket Ahmad; Maqsood, Syed Raashid; Peerzada, Ghulam Mustafa

doi:10.1134/s1061934815050093

Cited by 19 publications

(23 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This research focused on Cu(II) species for two reasons. First, Cu(I) is not stable in aqueous solutions and undergoes conversion to Cu(II) [ 37 ]. The creation of the Cu(I) complexes in aqueous solutions would require characterization to ensure that the Cu(I) and not the Cu(II) complexes was being synthesized.…”

Section: Discussionmentioning

confidence: 99%

Copper (II) complexes of bidentate ligands exhibit potent anti-cancer activity regardless of platinum sensitivity status

Wehbe

Leung

et al. 2017

Invest New Drugs

View full text Add to dashboard Cite

SummaryInsensitivity to platinum, either through inherent or acquired resistance, is a major clinical problem in the treatment of many solid tumors. Here, we explored the therapeutic potential of diethyldithiocarbamate (DDC), pyrithione (Pyr), plumbagin (Plum), 8-hydroxyquinoline (8-HQ), clioquinol (CQ) copper complexes in a panel of cancer cell lines that differ in their sensitivity to platins (cisplatin/carboplatin) using a high-content imaging system. Our data suggest that the copper complexes were effective against both platinum sensitive (IC50 ~ 1 μM platinum) and insensitive (IC50 > 5 μM platinum) cell lines. Furthermore, copper complexes of DDC, Pyr and 8-HQ had greater therapeutic activity compared to the copper-free ligands in all cell lines; whereas the copper-dependent activities of Plum and CQ were cell-line specific. Four of the copper complexes (Cu(DDC)2, Cu(Pyr)2, Cu(Plum)2 and Cu(8-HQ)2) showed IC50 values less than that of cisplatin in all tested cell lines. The complex copper DDC (Cu(DDC)2) was selected for in vivo evaluation due to its low nano-molar range activity in vitro and the availability of an injectable liposomal formulation. Liposomal (Cu(DDC)2) was tested in a fast-growing platinum-resistant A2780-CP ovarian xenograft model and was found to achieve a statistically significant reduction (50%; p < 0.05) in tumour size. This work supports the potential use of copper-based therapeutics to treat cancers that are insensitive to platinum drugs.

show abstract

Section: Discussionmentioning

confidence: 99%

Copper (II) complexes of bidentate ligands exhibit potent anti-cancer activity regardless of platinum sensitivity status

Wehbe

Leung

et al. 2017

Invest New Drugs

View full text Add to dashboard Cite

show abstract

“…Significant current raising up could be observed close to 2 V in case of acetonitrile; thus, this solvent provides a wide potential window for studying different compounds. Due to this property, acetonitrile is widely used as an inert non-aqueous solvent [33][34][35]. Compared with the other selected solvents, it has far the smallest background current except for tetrahydrofuran.…”

Section: Cyclic Voltammetric Studies Of Phenol In the Different Solventsmentioning

confidence: 99%

Investigation of phenol electrooxidation in aprotic non-aqueous solvents by using cyclic and normal pulse voltammetry

et al. 2019

View full text Add to dashboard Cite

Electrooxidation of phenol was studied on platinum electrode in five aprotic nonaqueous solvents (acetonitrile, dimethyl sulfoxide, dimethyl formamide, acetone, and tetrahydrofuran) with cyclic and normal pulse voltammetry. The cyclic voltammetric results showed that fouling of the electrode surface by the polyphenol took place continuously in dimethyl formamide and a weak passivation of the electrode could be observed in dimethyl sulfoxide. From this solvent, a coherent and mechanically removable, weakly adsorbed layer could be obtained. In the other three solvents, the electrode passivated completely after five scans. Diffusion barrier properties of the polymer formed in acetone were the most pronounced of all solvents towards a redox probe. Normal pulse voltammetric investigations showed that the extent of electrode passivation is insignificant in three of the solvents used. It was due to the application of the short anodic potential pulses where the oxidation of phenol occurred and the formed oligomers diffused into the bulk of solution.

show abstract

“…Formation of the ion pair leads to lower solvolysis energy of the precursor complex thereby minimizing the activation barrier for the electron transfer. Based on this synergistic effect, Masood and coworkers [29] proposed an electroanalytical method for probing the composition of Cu(I) thiourea complexes via oxidation of coordinated thiourea by Cu(II) perchlorate in acetonitrile medium (Fig. 14).…”

Section: Solvent Coordination and Ion Pair Formation For Expansion Inmentioning

confidence: 98%

Complexation modulated redox behavior of transition metal systems (review)

Rizvi

2015

Russ J Gen Chem

View full text Add to dashboard Cite

Ligand effect is a favorable factor in modulation of redox potential of transition metal ion oxidation-reduction systems. Coordination promoted redox action of transition metals can be an efficient approach to design of new redox systems with specific applications. The current review is devoted to the complexation effect of selected ligands on the redox potential of iron, cobalt and copper redox couples and application of such systems in analytical estimations. Indirect estimation of non redox systems by a non redox reaction over a platinum electrode has been referred to as a pseudo indicator action. Application of coordination modulated redox potentials in the natural attenuation of toxic environmental contaminants is also presented.1 The text was submitted by the author in English.Complexation effect on redox potential. Redox systems with tailor made potentials are desired for applications in artificial photosynthetic reactions [1], fuel cell catalysts solar energy conversions [2], hydrogen production and bio-memitic chemistry [3]. Complexation with an appropriate ligand can modulate the redox potential of transition metals redox couples beyond the natural range [4,5]. The complexation effect on redox potential can be explained by specific stabilization of transition metal oxidation states in a redox couple. The complexation effect on redox potential can be rationalized using the thermochemical cycle (Scheme 1) [7,8]. The ligand effect is the promising phenomenon in the design and development of redox potentials with desired applications [6].According to Eq. (3) the ratio of formation constants β III /β II modulates the redox potential of a redox couple in complexes. With the proper adjustment of the ratio the redox potential can be tuned to any desired value. Thus the electrochemical behavior of transition metals ions is also modified by the complexation effect which leads to a different reduction potential in the complexed state compared to the free state [Eq. (3)]. The complexation effect on redox potentials helps to understand mechanisms of the natural redox processes [9],Scheme 1. Thermochemical cycle for complexation effect on redox potential. M 3+ aqua M 2+ aqua ΔG 1 e − ΔG 3 nL ΔG 2 nL M 3+ complex M 2+ complex ΔG 4 e − (3) E complex = E aqua − RT nF ln β III β II . ΔG 1 + ΔG 2 = ΔG 3 + ΔG 4 , ΔG 1 = −nFE aqua ; ΔG 2 = −RTln β II , ΔG 3 = −RTln β III ; ΔG 4 = −nFE complex , ΔG 4 = (ΔG 1 + ΔG 2 ) − ΔG 3 , −nFE complex = −nFE aqua + RT nF ln β III β II ,

show abstract

Synergistic effect of perchlorate ions and acetonitrile medium explored for extension in copper redoximetry

Cited by 19 publications

References 48 publications

Copper (II) complexes of bidentate ligands exhibit potent anti-cancer activity regardless of platinum sensitivity status

Copper (II) complexes of bidentate ligands exhibit potent anti-cancer activity regardless of platinum sensitivity status

Investigation of phenol electrooxidation in aprotic non-aqueous solvents by using cyclic and normal pulse voltammetry

Complexation modulated redox behavior of transition metal systems (review)

Contact Info

Product

Resources

About