Universidade Federal do Ceará
PPGEQ – Programa de Pós-graduação em Engenharia Química

Medical devices designed to be used incontact with bloodcaninduce several biological effects in the patient, such as the thrombus formation and complement system activation.Anstrategy to avoid these adverse effects is the coating of the surfaceswithhemocompatible and not immunogenicpolymers.Thisstudy aimed to developsulfated chitosanfilms withhemocompatiblecharacteristicsfor biomedical applications. Natural and sulfated chitosan films (QN and QS, respectively) were characterized by Elemental Analysis,Infraredspectroscopy (FTIR-ATR), Proton and Carbon Nuclear Magnetic Resonance(1H e 13C-NMR), Viscometry, GelPermeation Chromatography(GPC), Scanning Electron MicroscopywithEDX(SEM/EDX), X-raydiffraction(XRD) and Thermogravimetricanalysis (TGA).Thefilms hemocompatibilitywas analyzed studyingtheglobular protein adsorption (BSA and fibrinogen), platelet adhesion, anticoagulant activity and cytotoxicity by LDH (lactate dehydrogenase).The elemental analysisdemonstrated the sulfur presence in the sulfated films. TheFTIR-ATR results confirmed the sulfation reaction, with the appearance oftwo new bandsat1206cm -1 (S = O)and794cm -1(C-S-O), assigned at sulfur group. The filmQS6 with the highest sulfation degree (GS =1.37)was selectedto perform the followinganalyzes. The1HNMRanalysisshoweddeacetylation degree (DD)of 77% and 58% for the natural andsulfatedchitosan,respectively. 13CNMRanalysis showed that chitosan was partially sulfated, obtaining 2,N-3,6,O-sulfated chitosan.The mass molecular (MM) of QN and QS were 78.093 Daand 5.050 Da,respectively, determined by viscometry.Homogeneous andsmooth surfaceswere observedby SEM/EDX images. TheXRDshowedsemi-crystallinepeaks fornaturalchitosan, while an amorphous structure was observedfor sulfatedchitosan.TheTGA analysesrevealeda reduction in the thermal stability to sulfatedchitosan comparedto natural chitosan.The hemocompatibility results showed that chemical modification on chitosan chain was able todecrease the BSA (36.8%) and fibrinogen (20%) adsorption and mainly the platelet adhesion (93.7%) in relation to QN, either by SEM and optical microscopy images.Only the QS presentedanticoagulant activity in the intrinsic pathway (72.15s, 200µg/mL) compared with the QN (26.57s, 200µg/mL).It was also observed atoxicity of thestudied polymers. Theseresults indicate that sulfated chitosan films have hemocompatibility properties promising to blood-materials devices.