Cetyl trimethyl ammonium bromide

Ulvan (Ul), extracted from Ulva lactuca (molecular weight around 300 KDa) was kindly provided by Stemmaters, Portugal. Chondroitin sulfate (CS) sodium salt, extracted from bovine cartilage was provided by Carbosynth, UK. CS extracted from cat shark (Scyliorhinus canicula), CS extracted from blackmouth catshark (Galeus melastomus) and CS extracted from rabbit fish (Chimaera monstrosa) at the Instituto de Investigaciones Marinas (IIM-CSIC) [37 (link),38 (link),39 (link)] were also tested. Fucoidan (Fu) extracted from Fucus vesiculosus (92.7%) was provided by Marinova, Australia. Chitosan (CH) (low-molecular weight), glutaraldehyde (70% in water), acetic acid (≥99.7%) and sodium acetate were purchased from Sigma Aldrich, Germany. Metal cation salts such as lead nitrate, cadmium nitrate, copper sulphate, sodium fluoride and ferrous sulphate were supplied by Merck, Germany. Hydrochloric acid (≥37%), anhydrous glycerol (≥99.5%) and aluminum sulphate hexadecahydrate were purchased from Fluka, Switzerland, while eriochrome cyanine R was purchased from Riedel-de Haen, Germany. Nitric acid (65%) and cetyl trimethyl ammonium bromide were purchased from PanReac, Spain. Tetraethylorthosilicate (≥98%) was purchased from Acros Organics, Germany, and absolute ethanol was from Fischer Scientific, UK. Water used was of Milli-Q purity, Millipore, Massachusetts, EUA.