European Journal of Molecular & Clinical Medicine ISSN 2515-8260 Volume 07, Issue 10, 2020 2378 Antibacterial Finishing and Dyeing Affinity Enhancement of cellulose-based fabrics via pre-treatment by chitosan nanoparticles treatment Fatma A. Mohamed 1 , Maysa M. Reda 2 1 Textile Research Division, National Research Centre, 33 El Bohouth St. (Former El Tahrir St.), Dokki, Giza, Egypt, P.O.12622 2 High institute of applied arts, the 5PthP District, Cairo, Egypt * maysareda@aol.com Abstract: Chitosan nanoparticles were prepared as green antibacterial finishing material and enhance antimicrobial activity of cellulose-based fabrics such as cotton and viscose. Two new bifunctional dye Bis (monochlorotriazine) (MCT) and hetero bifunctional (SES/MCT) reactive dyes have been prepared in previous work. Dimedone moiety (5,5- Dimethylcyclohexane-1,3-dione) and applied in cellulose-based fabrics with various chitosan nanoparticles concentrations imparting them antimicrobial activity. In this work the effect of chitosan nanoparticles on dye ability of cellulose-based fabrics were studied from evaluation of the colour strength expressed in K/S values of the dyed fabrics at different concentration of chitosan nanoparticles and the two synthesized used dyes. Results showed that chitosan nanoparticles treated cellulose-based fabrics have higher affinity towards dyeing than untreated cellulose-based fabrics. Also, the antimicrobial properties of the treated fabrics were higher than that of untreated fabrics and give higher exhaustion without using any salts and alkalinity. So, chitosan nanoparticles exhibit cellulose based fabrics high antimicrobial and having dyeing affinity than untreated one. Also, treated dyed fabrics showed very good to excellent fastness properties. Keywords: chitosan nanoparticles; cotton; viscose; antimicrobial; dyeability; fungi; bacteria; Reactive dyes 1. INTRODUCTION Cotton fabrics is a natural linear polymer with repeating units of cellobiose. It is very popular among other natural fabrics because of its properties e.g. e.g. it is soft, breathable and wear comfort [1-3]. On the other hand, it has low ultraviolet protective, hygroscopic nonconductive so that its applications are limited without modification [4-6]. Cotton fabrics contains three hydroxyl groups on its structure can form partial negative charge on their surface in aqueous medium [7,8]. Most of dyes used for cotton fabrics has ionic nature and cause electrostatic repulsion with cotton negative charges [9-13]. This repulsion between dyes and fabrics reduces the dye exhaustion from dye bath into the fabrics and this can be overcome. Addition of salt can