2 bromo 2 methylpropionic acid

All chemicals were used as supplied unless otherwise stated. Acetone, dichloromethane, toluene, methanol, diethyl ether were purchased from Fischer Scientific at laboratory grade. Dodecane thiol (≥98%), potassium phosphate tribasic (≥98%), carbon disulfide (99%), N-hydroxethyl acrylamide (97%), 4,4′-azobis(4-cyanovaleric acid) (98%), mesitylene (reagent grade), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (≥98%) were all purchased from Sigma-Aldrich. 2-Bromo-2-methylpropionic acid (98%), 4-(dimethylamino)pyridine (99%), pentafluorophenol (99%), triethylamine (99%) were purchased from Acros. Microtitre plates were purchased from Greiner Bio-one. 10 mmol HEPES buffer containing 0.05 M NaCl, 0.1 mM CaCl₂ and 0.01 mM MnCl₂ (pH 7.5, HEPES) was prepared in 200 mL of milliQ water (with a resistance > 19 mOhms). 60 nm gold nanoparticles were obtained from BBI solutions. Concanavalin A and soybean agglutinin and Ricinus communis agglutinin-120 were purchased from Vector Labs.