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Buckypaper as absorbable adhesive for surgical applications
No full textFONANZIAMENTO pROGETTO DI RICERCA INTERFACOLTA' dIP pARIDE sTEFANINI Chirurgia Generale e Dip di Chimica Anno 2010 prot C26A10HCNR per 5333€ di 35000€TOPICS: Biotecnologia ed innovazioni tecnologiche. Le proposte italiane nella ricerca.
BUCKYPAPER AS ABSORBABLE ADHESIVE FOR SURGICAL APPLICATIONS
Massimo Chiaretti(1), Andrea Martinelli(2), Giovanna Angela Carru(3), Fabio Procacciante(1), Lucio D’Ilario(2), Emanuela D’Amore(4), Alessandra Maria Chiaretti(5), Fabio Faiola(6) and Paola Consentino(7).
(1)Department of General Surgery “Paride Stefanini”, Sapienza University of Rome, Viale del Policlinico 155, Rome, 00161 (Italy)
(2)Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, Rome, 00185 (Italy)
(3)Policlinico Umberto I Hospital, Sapienza University of Rome, Viale del Policlinico 155, 00161 - Rome (Italy)
(4)National Health Institute, Viale Regina Elena 299, 00161 - Rome (Italy)
(5)Biologic Sciences Faculty, University of Rome, P.le Aldo Moro 5, Rome, 00185 (Italy)
(6)Department of Molecular Medicine, Sapienza University of Rome, Viale Regina Elena 324, Rome, 00161 (Italy)
(7)Appialab Srl V. Latina, 286 00179 Rome (+39) 067825111www.appialab.it
E-mail: [email protected]
Keywords: buckypaper, carbon nanotubes, medical application, abdominal surgery, wet adhesion absorbable adhesive device.
Introduction: The adhesion of a surface on a biological tissue represents an important scientific and technological issue which excites the interest of many researchers. One of the main problems related to the abdominal prosthetic surgery is the mesh fixation. On the one hand suture line tension, mesh separation or displacement, improper and blind application of metal tacks and staples in laparoscopy surgery are the main causes of complications, including seroma, postoperative pain and recurrence[6-9]. On the other hand, the use of human fibrin as glue between the prosthesis and the damaged tissue, although it has become a well-established surgical procedure, presents possible risks associated to the transmission of unknown diseases related to the use of human blood-derived materials [9]. Moreover, it was observed that an increased incidence of postoperative seroma is associated to the use of fibrin glue for mesh fixation[10]. Surfaces able to adhere promptly and strongly on wet biological tissue may represent an effective alternative to the conventional prosthesis fixation methods. This study proposes the application of the nature inspired micro- or nano-patterned adhesive surfaces, by exploiting the scaling effect, according to which the adhesion strength can be enhanced through the reduction of interface adhesive contact size. We experimented evidences on the potential applicability on wet biological tissue of the Buckypaper (BP) as an adhesive tape: BP is a self-standing felt composed of entangled multi-walled carbon nanotubes. In vitro bench surgery mechanical peeling and shear adhesion tests and In vivo tests If compared to other commercial tested prosthesis meshes, BP shows a stronger adhesion, only on wet tissues. much better than both self-gripping commercial mesh and fibrin-glue non-gripping meshes and fabrics. Prompted by these results, we implanted BP in rabbits, to assess its effectiveness as adhesive absorbable prosthetic device and its biocompatibility. After 35 days from the operation we observed that no rabbit behavioral alteration occurred; the BP samples preserved their position in the implantation site and mechanical adhesion was enhanced. This is indicative of no toxicity, good integration and slow reabsorption of the synthetic material into the surrounding tissue without eliciting adverse reactions. Materials and Methods. Operated New Zeeland 3000g female rabbits (R1-R4) did not show mortality or morbidity, no significant neurovegetative or behavioral differences in comparison with the no operated control R5. Results and Discussion. Body weight monitoring graph do not showed any significant difference. The Hematoxilin and Eeosin (H&E) stained implant section reported BP surface fragmentation, shows the formation of a capsule of loose fibrous tissue, consisting of fibroblasts and collagen fibers, indicative of a weak inflammation reaction., the necroscopy examination of R2 showed that the implanted PP favors a cicatrisation process, the mesh appearing wrapped in the inflammatory reaction. In R4, the no sutured incision, tighten by the BP strep, was normally closed and healed. On the smooth BP surface facing the abdominal cavity, explanted from R3, a scarcely adherent neo-formed protein fibrous carpet, about 5 mm thick, may be observed in scansion electronic microscope (SEM). Conclusions: by peeling and shear mechanical tests, a strong BP adhesion on wet biological tissue was measured. In view of a possible application as adhesive absorbable tape in surgery, preliminary in vivo experiments were carried out on rabbit model. Necroscopical and histological investigations enlighten that 35 days after the implantation, the BP elicits minimal adverse tissue response, and when exposed to the peritoneal cavity, no adhesion of omentum or intestinal loops was observed. Nanometric carbon nanotube aggregates, deriving from the surface BP fragmentation, were phagocytised by macrophages and observed in Bowman's urinary space. The assessment of the BP debris, possible toxicity or confinement or metabolism and accumulation or excretion mechanism needs further studies. However, we believe that the results here reported can be used to propose the BP as a new wet absorbable adhesive tape to fix prosthetic materials.
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11. massimochiaretti.wordpress.co
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