Dendrimer-Functionalized Metal Oxide Nanoparticle-Mediated Self-Assembled Collagen Scaffold for Skin Regenerative Application: Function of Metal in Metal Oxides.

Functionalized metal oxide nanoparticles cross-linked collagen scaffolds are widely used in skin regenerative applications because of their enhanced physicochemical and biocompatibility properties. From the safety clinical trials point of view, there are no reports that have compared the effects of functionalized metal oxide nanoparticles mediated collagen scaffolds for in vivo skin regenerative applications. In this work, triethoxysilane-poly (amido amine) dendrimer generation 3 (TES-PAMAM-G or G)-functionalized spherical shape metal oxide nanoparticles (MO NPs: ZnO, TiO, FeO, CeO, and SiO, size: 12-25 nm) cross-linked collagen scaffolds were prepared by using a self-assembly method.

Polymethyl methacrylate (PMMA) grafted collagen scaffold reinforced by PdO-TiO nanocomposites.

In the past few decades, the design and fabrication of bio-scaffolds exhibiting structural stability in long-term and biocompatibility has received much attention in the field of tissue engineering application. In this direction, we have synthesized different mole ratio of PdO-TiO nanocomposites (1:1, 2:1 and 3:1 of Pd:Ti, size 5-11nm, 7-16 nm and 9-22 nm) through a simple single step sol-gel method. The obtained nanocomposites of different sizes were assimilated into poly (methyl methacrylate) grafted collagen biopolymer (g-PMMA-Collagen), resulting in a PdO-TiO-g-PMMA-Collagen based scaffold.

Photocrosslinking of collagen using Ru(II)-polypyridyl complex functionalized gold nanoparticles.

Collagen, an extracellular matrix protein, has been used for diverse biological applications due to its clinically safe in nature and for the development of various biomedical devices. As the ECM protein is prone to degradation process, it is necessary to stabilize the collagen. In the present study, we have carried out the stabilization of collagen using newly synthesized gold nanoparticles conjugated with Ru(II) complexes (NCs) possessing different ligand environment.

Effect of functionalized gold nanoparticle on collagen stabilization for tissue engineering application.

Functionalization of nanoparticle with specific groups is one of the most straightforward strategies to induce structural stability and specific cell responses from collagen based biomaterials. The effect of functionalised nanoparticles on triple helical conformational changes in collagen has not been understood well. For understanding the role of functionalization on collagen conformation, gold nanoparticles (Au NPs) prepared through wet chemical methods and functionalized with organic molecules (F-AuNPs) such as self-assembled monolayer (SAM), (3-aminopropyl) triethoxysilane (APTES), Polysaccharides (pectin and chitosan) and Poly(amido amine) PAMAM dendrimer (G), were characterised and their interaction with collagen was studied.

Novel mononuclear Cu (II) terpyridine complexes: Impact of fused ring thiophene and thiazole head groups towards DNA/BSA interaction, cleavage and antiproliferative activity on HepG2 and triple negative CAL-51 cell line.

Two mononuclear copper (II) terpyridine complexes namely, [Cu(Btptpy) (ClO)](ClO) 1, and [Cu(Bttpy) (ClO)](ClO) 2, (Btptpy (L) = 4'-(Benzothiophene)-2,2':6',2″-terpyridine, Bttpy (L) = 4'-(Benzylthiazolyl)-2,2':6',2″-terpyridine) have been synthesized and characterized. Single crystal X-ray diffraction shows that, both ligands belong to monoclinic crystal system with space group P2/c (L) and P2/n (L). Absorption spectral titration, DNA melting study, circular dichroism and viscosity measurement reveal that, complex 1 and 2 bind with DNA through intercalation.

Catechin tuned magnetism of Gd-doped orthovanadate through morphology as T-T MRI contrast agents.

Tetragonal (t)-LaVO has turned out to be a potential host for luminescent materials. Synthesis of t-LaVO till date has been based on chelating effect of EDTA making it not ideal for bioimaging applications. An alternative was proposed by us through the use of catechin.

Nanorod mediated collagen scaffolds as extra cellular matrix mimics.

Creating collagen scaffolds that mimic extracellular matrices without using toxic exogenous materials remains a big challenge. A new strategy to create scaffolds through end-to-end crosslinking through functionalized nanorods leading to well-designed architecture is presented here. Self-assembled scaffolds with a denaturation temperature of 110 °C, porosity of 70%, pore size of 0.

Dual utility of a novel, copper enhanced laccase from Trichoderma aureoviridae.

Ever since the ability of laccase to oxidize non-phenolic lignin models was described, the oxidative degradation reactions catalyzed by laccase have been widely studied for paper pulp production or detoxification of aromatic pollutants. The viability of developing eco-friendly, laccase aided industrial processes has been explored. Here, we report the isolation and screening of fungi to explore their lignolytic ability on solid media using various substrates as indicators.

Go natural and smarter: fenugreek as a hydration designer of collagen based biomaterials.

Collagen-based biomaterials have received considerable attention for smarter biomedical applications due to their inherent superior mechano-biological properties. However, accumulating evidence suggests that water, as a probe liquid bound in collagen, might be investigated to explore the influence of additives on the static and dynamic solvation behavior of collagen. The structure and dynamics of water near the surface/interface of collagen-fenugreek composites were demonstrated via circular dichroic spectroscopy, thermoporometry and impedimetric measurements to enlighten about the configuration-function relationship of collagen.

Fluorescent nanonetworks: a novel bioalley for collagen scaffolds and tissue engineering.

Native collagen is arranged in bundles of aligned fibrils to withstand in vivo mechanical loads. Reproducing such a process under in vitro conditions has not met with major success. Our approach has been to induce nanolinks, during the self-assembly process, leading to delayed rather than inhibited fibrillogenesis.

DNA/protein interaction and cytotoxic activity of imidazole terpyridine derived Cu(II)/Zn(II) metal complexes.

Two imidazole terpyridine (itpy) based complexes, [Cu(itpy)(OAc)(H2O)]NO3·H2O (1) and [Zn(itpy)(OAc)]OAc (2) have been synthesised and characterized. The crystal structure of complex 1 shows distorted octahedral geometry with an anti-parallel stacking arrangement. The interactions of the two complexes with Calf thymus DNA (ctDNA) have been studied using absorption titration and circular dichroism.

DNA condensation by copper(II) complexes and their anti-proliferative effect on cancerous and normal fibroblast cells.

In our search towards copper(II) based anticancer compounds, copper(II) complexes [Cu(bitpy)2](ClO4)21, [Cu(bitpy)(phen)](NO3)22 and [Cu(bitpy)(NO3)](NO3) 3 were synthesized and characterized. All the three complexes contain the tridentate ligand bitpy, which bears biologically relevant benzimidazolyl head group, as one of the ligands. Because of the presence of the planar benzimidazolyl group in the bitpy ligand, the complexes exhibited intercalative mode of binding with DNA.

Investigation of nuclease, proteolytic and antiproliferative effects of copper(II) complexes of thiophenylmethanamine derivatives.

Four coordinate copper(II) complexes 1, 2 and 3 of ligands based on thiophenemethylamine containing imidazole, benzimidazole and pyridine moiety have been synthesized and characterized. Complex 1 has also been crystallographically characterized. The three complexes bind to DNA non-intercalatively, though partial intercalation in the case of complex 2 cannot be ruled out.

Influence of PCL on the material properties of collagen based biocomposites and in vitro evaluation of drug release.

Formulation of biodegradable collagen-poly-ε-caprolactone (PCL) based biomaterials for the sustained release of insulin is the main objective of the present work. PCL has been employed to modulate the physico-chemical behavior of collagen to control the drug release. Designed formulations were employed to statistically optimize insulin release parameter profile at different collagen to PCL molar ratios.

Importance of ligand structure in DNA/protein binding, mutagenicity, excision repair and nutritional aspects of chromium(III) complexes.

Chromium is extensively used in leather, chrome plating and refining industries. On one hand the occupational exposure to chromium leads to cancer, whereas on the contrary certain Cr(III) compounds have been proposed as nutritional supplements for Type II diabetes and as muscle building agents. Despite the positive outlook of chromium as a bio-essential element, there is increasing concern over the therapeutic application of Cr(III) based supplements, its bioavailability and toxicity profile.

Copper(II) complexes of terpyridine derivatives: a footstep towards development of antiproliferative agent for breast cancer.

Two copper(II) complexes with terpyridyl conjugates, [Cu(meotpy)(dmp)](NO(3))(2) (1) and [Cu(bitpy)(dmp)](NO(3))(2) (2) where meotpy, bitpy and dmp stand for methoxybenzyl terpyridine, benzimidazolyl terpyridine and dimethyl phenanthroline respectively have been synthesized and characterized. Complex 1 has also been characterized crystallographically. Both the complexes have been found to bind CT-DNA intercalatively.

Effect of coordinated ligands on antiproliferative activity and DNA cleavage property of three mononuclear Cu(II)-terpyridine complexes.

Three mononuclear copper(II) complexes, [Cu(tpy)Cl(2)] 1, [Cu(tpy)(NO(3))(2)(H(2)O)] 2 and [Cu(Ptpy)Cl(2)]·H(2)O·HCl 3 have been synthesised and characterized by various spectroscopic techniques and single crystal X-ray diffraction. Complexes 1 and 3 have five coordinate geometry in solid state, whereas complex 2 has six coordinate geometry. Mass spectral and EPR evidence suggest that in solution all the three complexes exist predominantly as a four coordinate species.

Enhancing collagen stability through nanostructures containing chromium(III) oxide.

Stabilization of collagen for various applications employs chemicals such as aldehydes, metal ions, polyphenols, etc. Stability against enzymatic, thermal and mechanical degradation is required for a range of biomedical applications. The premise of this research is to explore the use of nanoparticles with suitable functionalization/encapsulation to crosslink with collagen, such that the three dimensional architecture had the desired stability.

Ruthenium(II) [3 + 2 + 1] mixed ligand complexes: substituent effect on photolability, photooxidation of bases, photocytotoxicity and photonuclease activity.

Mixed ligand complexes of ruthenium(II), [Ru(itpy)(bpy)Cl]ClO(4)1, [Ru(itpy)(phen)Cl]ClO(4)2, [Ru(bitpy)(bpy)Cl]ClO(4)3 and [Ru(bitpy)(phen)Cl]ClO(4)4 have been synthesized and characterized. Complex 3 has also been characterized crystallographically. These complexes exhibit photolability of the Ru-Cl bond.

Structurally modified 1,10-phenanthroline based fluorophores for specific sensing of Ni2+ and Cu2+ ions.

We report two fluorophores with open coordination sites for specific sensing of Ni(2+) and Cu(2+) ions via a simple synthetic route. The fluorescence activity was completely quenched on coordination of the metal ions with the phenanthroline ring present in the fluorophore as is clearly evident from the photophysical studies.

Effect of UV irradiation on the physico-chemical properties of iron crosslinked collagen.

Collagen is the main component of connective tissue and finds immense applications as a biomaterial. In this study, effect of UV irradiation on collagen crosslinked with iron has been carried out. The physical and optical properties of crosslinked collagen affected by UV irradiation were analyzed using electrospectral and fluorescence studies.

Cytotoxic copper (II) mixed ligand complexes: crystal structure and DNA cleavage activity.

Two new mixed ligand complexes of copper (II) containing an imidazolyl terpyridine ligand, [Cu(Itpy)(bpy)](ClO(4))(2)·(H(2)O), 1, and [Cu(Itpy)(phen) (ClO(4))](ClO(4))·(H(2)O), 2 have been synthesized and characterized. Complex 1 has been found to possess a distorted square pyramidal geometry whereas 2 exhibit a distorted octahedral geometry. Electronic spectral titrations suggest that 1 and 2 bind to DNA intercalatively with the binding constant, K(b) (4.