The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Nevio Picci - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant multi walled carbon nanotubes by free radical Grafting of gallic acid new materials for biomedical applications
Journal of Pharmacy and Pharmacology, 2011Co-Authors: Giuseppe Cirillo, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Umile Gianfranco Spizzirri, Silke Hampel, R Klingeler, Nevio PicciAbstract:Objectives To prove the possibility of covalently functionalizing multi-walled carbon nanotubes (CNTs) by free radical Grafting of gallic acid on their surface with the subsequent synthesis of materials with improved biological properties evaluated by specific in-vitro assays. Methods Antioxidant CNTs were synthesized by radical Grafting of gallic acid onto pristine CNTs. The synthesis of carbon nanotubes was carried out in a fixed-bed reactor and, after the removal of the amorphous carbon, the Grafting process was performed. The obtained materials were characterized by fluorescence and Fourier transform infrared spectroscopy (FT-IR) analyses. After assessment of the biocompatibility and determination of the disposable phenolic group content, the antioxidant properties were evaluated in terms of total antioxidant activity and scavenger ability against 2,2′-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and peroxyl radicals. Finally the inhibition activity on acetylcholinesterase was evaluated. Key findings The covalent fuctionalization of CNTs with gallic acid was confirmed and the amount of gallic acid bound per g of CNTs was found to be 2.1 ± 0.2 mg. Good antioxidant and scavenging properties were recorded in the functionalized CNTs, which were found to be able to inhibit the acetylcholinesterase with potential improved activity for biomedical and pharmaceutical applications. Conclusions For the first time, a free radical Grafting Procedure was proposed as a synthetic approach for the covalent functionalization of CNTs with an antioxidant polyphenol.
-
Antioxidant―polysaccharide conjugates for food application by eco-friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Umile Gianfranco Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
antioxidant polysaccharide conjugates for food application by eco friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Gianfranco U Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
covalent insertion of antioxidant molecules on chitosan by a free radical Grafting Procedure
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Umile Gianfranco Spizzirri, Nevio PicciAbstract:In this work, the synthesis of gallic acid−chitosan and catechin−chitosan conjugates was carried out by adopting a free radical-induced Grafting Procedure. For this purpose, an ascorbic acid/hydrogen peroxide redox pair was employed as radical initiator. The formation of covalent bonds between antioxidant and biopolymer was verified by performing UV, FT-IR, and DSC analyses, whereas the antioxidant properties of chitosan conjugates were compared with that of a blank chitosan, treated in the same conditions but in the absence of antioxidant molecules. The good antioxidant activity shown by functionalized materials proved the efficiency of the reaction method.
Giuseppe Cirillo - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant multi walled carbon nanotubes by free radical Grafting of gallic acid new materials for biomedical applications
Journal of Pharmacy and Pharmacology, 2011Co-Authors: Giuseppe Cirillo, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Umile Gianfranco Spizzirri, Silke Hampel, R Klingeler, Nevio PicciAbstract:Objectives To prove the possibility of covalently functionalizing multi-walled carbon nanotubes (CNTs) by free radical Grafting of gallic acid on their surface with the subsequent synthesis of materials with improved biological properties evaluated by specific in-vitro assays. Methods Antioxidant CNTs were synthesized by radical Grafting of gallic acid onto pristine CNTs. The synthesis of carbon nanotubes was carried out in a fixed-bed reactor and, after the removal of the amorphous carbon, the Grafting process was performed. The obtained materials were characterized by fluorescence and Fourier transform infrared spectroscopy (FT-IR) analyses. After assessment of the biocompatibility and determination of the disposable phenolic group content, the antioxidant properties were evaluated in terms of total antioxidant activity and scavenger ability against 2,2′-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and peroxyl radicals. Finally the inhibition activity on acetylcholinesterase was evaluated. Key findings The covalent fuctionalization of CNTs with gallic acid was confirmed and the amount of gallic acid bound per g of CNTs was found to be 2.1 ± 0.2 mg. Good antioxidant and scavenging properties were recorded in the functionalized CNTs, which were found to be able to inhibit the acetylcholinesterase with potential improved activity for biomedical and pharmaceutical applications. Conclusions For the first time, a free radical Grafting Procedure was proposed as a synthetic approach for the covalent functionalization of CNTs with an antioxidant polyphenol.
-
Antioxidant―polysaccharide conjugates for food application by eco-friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Umile Gianfranco Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
antioxidant polysaccharide conjugates for food application by eco friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Gianfranco U Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
covalent insertion of antioxidant molecules on chitosan by a free radical Grafting Procedure
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Umile Gianfranco Spizzirri, Nevio PicciAbstract:In this work, the synthesis of gallic acid−chitosan and catechin−chitosan conjugates was carried out by adopting a free radical-induced Grafting Procedure. For this purpose, an ascorbic acid/hydrogen peroxide redox pair was employed as radical initiator. The formation of covalent bonds between antioxidant and biopolymer was verified by performing UV, FT-IR, and DSC analyses, whereas the antioxidant properties of chitosan conjugates were compared with that of a blank chitosan, treated in the same conditions but in the absence of antioxidant molecules. The good antioxidant activity shown by functionalized materials proved the efficiency of the reaction method.
Han Chunmao - One of the best experts on this subject based on the ideXlab platform.
-
the effect of collagen chitosan porous scaffold thickness on dermal regeneration in a one stage Grafting Procedure
Journal of The Mechanical Behavior of Biomedical Materials, 2014Co-Authors: Shi Haifei, Wang Xingang, Wu Shoucheng, Mao Zhengwei, You Chuangang, Han ChunmaoAbstract:Abstract Dermal substitutes are used as dermal regeneration templates to reduce scar formation and improve wound healing. Unlike autografts, dermal substitutes lack normal vascular networks. The increased distance required for diffusion of oxygen and nutrients to the autograft following interpositioning of the substitute dramatically affects graft survival. To evaluate the effect of collagen–chitosan scaffold thickness on dermal regeneration, single-layer collagen–chitosan porous scaffolds of 0.5-, 1- and 2-mm thicknesses were fabricated and used to treat full-thickness wounds in a one-stage Grafting Procedure in a rat model. Skin-graft viability, wound contraction, histological changes, and wound tensile strength were evaluated. The results indicated that the distance for the diffusion of oxygen and nutrients to the autograft in the 2-mm-thick scaffold provided less support for graft take, which resulted in graft necrosis, extensive inflammatory reaction, marked foreign-body reaction (FBR), rapid scaffold degradation, and abnormal collagen deposition and remodeling. In contrast, the thinner scaffolds, especially of that 0.5-mm thickness, promoted earlier angiogenesis, ensuring skin-graft viability with a mild FBR, and ordered fibroblast infiltration and better collagen remodeling. It can be concluded that collagen–chitosan porous scaffolds with a thickness of
-
The effect of collagen–chitosan porous scaffold thickness on dermal regeneration in a one-stage Grafting Procedure
Journal of The Mechanical Behavior of Biomedical Materials, 2013Co-Authors: Shi Haifei, Wang Xingang, Wu Shoucheng, Mao Zhengwei, You Chuangang, Han ChunmaoAbstract:Abstract Dermal substitutes are used as dermal regeneration templates to reduce scar formation and improve wound healing. Unlike autografts, dermal substitutes lack normal vascular networks. The increased distance required for diffusion of oxygen and nutrients to the autograft following interpositioning of the substitute dramatically affects graft survival. To evaluate the effect of collagen–chitosan scaffold thickness on dermal regeneration, single-layer collagen–chitosan porous scaffolds of 0.5-, 1- and 2-mm thicknesses were fabricated and used to treat full-thickness wounds in a one-stage Grafting Procedure in a rat model. Skin-graft viability, wound contraction, histological changes, and wound tensile strength were evaluated. The results indicated that the distance for the diffusion of oxygen and nutrients to the autograft in the 2-mm-thick scaffold provided less support for graft take, which resulted in graft necrosis, extensive inflammatory reaction, marked foreign-body reaction (FBR), rapid scaffold degradation, and abnormal collagen deposition and remodeling. In contrast, the thinner scaffolds, especially of that 0.5-mm thickness, promoted earlier angiogenesis, ensuring skin-graft viability with a mild FBR, and ordered fibroblast infiltration and better collagen remodeling. It can be concluded that collagen–chitosan porous scaffolds with a thickness of
Manuela Curcio - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant multi walled carbon nanotubes by free radical Grafting of gallic acid new materials for biomedical applications
Journal of Pharmacy and Pharmacology, 2011Co-Authors: Giuseppe Cirillo, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Umile Gianfranco Spizzirri, Silke Hampel, R Klingeler, Nevio PicciAbstract:Objectives To prove the possibility of covalently functionalizing multi-walled carbon nanotubes (CNTs) by free radical Grafting of gallic acid on their surface with the subsequent synthesis of materials with improved biological properties evaluated by specific in-vitro assays. Methods Antioxidant CNTs were synthesized by radical Grafting of gallic acid onto pristine CNTs. The synthesis of carbon nanotubes was carried out in a fixed-bed reactor and, after the removal of the amorphous carbon, the Grafting process was performed. The obtained materials were characterized by fluorescence and Fourier transform infrared spectroscopy (FT-IR) analyses. After assessment of the biocompatibility and determination of the disposable phenolic group content, the antioxidant properties were evaluated in terms of total antioxidant activity and scavenger ability against 2,2′-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and peroxyl radicals. Finally the inhibition activity on acetylcholinesterase was evaluated. Key findings The covalent fuctionalization of CNTs with gallic acid was confirmed and the amount of gallic acid bound per g of CNTs was found to be 2.1 ± 0.2 mg. Good antioxidant and scavenging properties were recorded in the functionalized CNTs, which were found to be able to inhibit the acetylcholinesterase with potential improved activity for biomedical and pharmaceutical applications. Conclusions For the first time, a free radical Grafting Procedure was proposed as a synthetic approach for the covalent functionalization of CNTs with an antioxidant polyphenol.
-
Antioxidant―polysaccharide conjugates for food application by eco-friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Umile Gianfranco Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
antioxidant polysaccharide conjugates for food application by eco friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Gianfranco U Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
covalent insertion of antioxidant molecules on chitosan by a free radical Grafting Procedure
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Umile Gianfranco Spizzirri, Nevio PicciAbstract:In this work, the synthesis of gallic acid−chitosan and catechin−chitosan conjugates was carried out by adopting a free radical-induced Grafting Procedure. For this purpose, an ascorbic acid/hydrogen peroxide redox pair was employed as radical initiator. The formation of covalent bonds between antioxidant and biopolymer was verified by performing UV, FT-IR, and DSC analyses, whereas the antioxidant properties of chitosan conjugates were compared with that of a blank chitosan, treated in the same conditions but in the absence of antioxidant molecules. The good antioxidant activity shown by functionalized materials proved the efficiency of the reaction method.
Ortensia Ilaria Parisi - One of the best experts on this subject based on the ideXlab platform.
-
antioxidant multi walled carbon nanotubes by free radical Grafting of gallic acid new materials for biomedical applications
Journal of Pharmacy and Pharmacology, 2011Co-Authors: Giuseppe Cirillo, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Umile Gianfranco Spizzirri, Silke Hampel, R Klingeler, Nevio PicciAbstract:Objectives To prove the possibility of covalently functionalizing multi-walled carbon nanotubes (CNTs) by free radical Grafting of gallic acid on their surface with the subsequent synthesis of materials with improved biological properties evaluated by specific in-vitro assays. Methods Antioxidant CNTs were synthesized by radical Grafting of gallic acid onto pristine CNTs. The synthesis of carbon nanotubes was carried out in a fixed-bed reactor and, after the removal of the amorphous carbon, the Grafting process was performed. The obtained materials were characterized by fluorescence and Fourier transform infrared spectroscopy (FT-IR) analyses. After assessment of the biocompatibility and determination of the disposable phenolic group content, the antioxidant properties were evaluated in terms of total antioxidant activity and scavenger ability against 2,2′-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl and peroxyl radicals. Finally the inhibition activity on acetylcholinesterase was evaluated. Key findings The covalent fuctionalization of CNTs with gallic acid was confirmed and the amount of gallic acid bound per g of CNTs was found to be 2.1 ± 0.2 mg. Good antioxidant and scavenging properties were recorded in the functionalized CNTs, which were found to be able to inhibit the acetylcholinesterase with potential improved activity for biomedical and pharmaceutical applications. Conclusions For the first time, a free radical Grafting Procedure was proposed as a synthetic approach for the covalent functionalization of CNTs with an antioxidant polyphenol.
-
Antioxidant―polysaccharide conjugates for food application by eco-friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Umile Gianfranco Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
antioxidant polysaccharide conjugates for food application by eco friendly Grafting Procedure
Carbohydrate Polymers, 2010Co-Authors: Gianfranco U Spizzirri, Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Nevio PicciAbstract:Abstract In the present study, catechin–alginate and catechin–inulin conjugates were obtained by adopting free radical-induced Grafting Procedure. In the aim to synthesize the antioxidant–polysaccharide conjugates, ascorbic acid/hydrogen peroxide redox pair was employed as water-soluble and biocompatible initiator system. The insertion of catechin onto the polymeric backbones was verified by performing FT-IR, DSC and fluorescence analyses and molecular weight distributions were analyzed by GPC. Finally, the antioxidant properties of the obtained conjugates were evaluated and compared with that of blank alginate and blank inulin, treated in the same conditions but in absence of catechin. The good antioxidant activity showed by functionalized materials confirmed the efficiency of the adopted reaction method to impart peculiar characteristics to macromolecules of natural origin for specific industrial applications. This kind of systems, indeed, could be very useful in the optimization of food preservation and to help manufacturers in elaboration of new food products and packaging.
-
covalent insertion of antioxidant molecules on chitosan by a free radical Grafting Procedure
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Manuela Curcio, Francesco Puoci, Francesca Iemma, Ortensia Ilaria Parisi, Giuseppe Cirillo, Umile Gianfranco Spizzirri, Nevio PicciAbstract:In this work, the synthesis of gallic acid−chitosan and catechin−chitosan conjugates was carried out by adopting a free radical-induced Grafting Procedure. For this purpose, an ascorbic acid/hydrogen peroxide redox pair was employed as radical initiator. The formation of covalent bonds between antioxidant and biopolymer was verified by performing UV, FT-IR, and DSC analyses, whereas the antioxidant properties of chitosan conjugates were compared with that of a blank chitosan, treated in the same conditions but in the absence of antioxidant molecules. The good antioxidant activity shown by functionalized materials proved the efficiency of the reaction method.
