In the last stage, L-asparagine and L-alanine QASs with quinine-derived cations were obtained using the previously obtained bromides as cation sources. First, the respective quaternary ammonium bromide (0.01 mol) was dissolved in ethanol (20 cm 3 ) and placed in a 50 cm 3 EasyMax™ reaction vessel equipped with a stir bar and a temperature sensor. Next, AmberLite™ HPR550 OH highly alkaline anionic resin (15 cm 3 ) was placed in the vessel, and the system was stirred for the next 15 minutes. The resin was subsequently filtered off from the post-reaction mixture and washed with 10 cm 3 of ethanol. In the next step, 20 cm 3 of aqueous solution containing 0.01 mol of the respective amino acid (L-asparagine, 1.321 g or L-alanine, 0.891 g) in zwitterionic form was added to the filtrate and the mixture was stirred for the next 30 minutes. The solvents were afterwards removed using a rotary vacuum evaporator, and the raw product was dissolved in 15 cm 3 of anhydrous methanol. In the next step, the resulting solution was filtered to remove any potential residue of unreacted amino acid. The solvent was afterwards removed using a rotary vacuum evaporator, and the residue was dried using a Schlenk line (pressure: 2•10 -5 bar) while heating to 40 °C for at least 8 hours. The obtained QASs were refrigerated at 4 °C in airtight vessels to prevent moisture absorption and potential decomposition.