Results published in 2015 in Applied Materials & Interfaces
The researchers form the Laboratory for Pulp and Paper Sciences and their colleagues have achieved the first chemical grafting of penicillin directly on the surface of micro-fibrillated cellulose films, giving them unprecedented nonleaching and contact active antimicrobial properties.
Micro-fibrillated cellulose is a bio-based material prepared from wood by a mechanical disintegration of the fibres. To exploit their amazing properties in the industry, one of the main challenges lies in the development of chemical modification processes aiming to increase the compatibility of micro-fibrillated cellulose with other materials or molecules, and produce a number of advanced materials with new functionalities.
An aqueous phase esterification
Working in this way, the researchers from the Laboratory for Pulp and Paper Sciences have designed a new esterification reaction under aqueous conditions, to covalently bind the antibiotic penicillin directly to the surface of micro-fibrillated cellulose films. This process was proved efficient in grafting the antibiotic in a way that confers the film an antimicrobial effect occurring exclusively by contact, preventing any leaching or diffusion in the medium as demonstrated by their colleagues from the Paper Division of INNOVHUB (Milano, Italy). Such strictly contact-active antibiotic materials could find many applications, particularly in medical, food packaging or for the design of wound dressings.
Pictorial representation of surface grafted micro-fibrillated cellulose film
Saini S, Belgacem N, Mendes J, Elegir G and Bras J, 2015 : Contact Antimicrobial Surface Obtained by Chemical Grafting of Microfibrillated Cellulose in Aqueous Solution Limiting Antibiotic Release. Applied Materials & Interfaces, 7, 18076-18085.