Hauv kev txiav txim siab dav dav, "amphoteric surfactant" yog ib lo lus sib sau ua ke ntawm ob lub ntsiab lus nqaim ntawm "amphoteric surfactant" thiab "amphoteric ionic surfactant," xa mus rau surfactants uas nws cov qauv molecular ib txhij muaj ob lossis ntau pawg hydrophilic: anionic, cationic, thiab nonionic. Amphoteric surfactants tshwj xeeb yog xa mus rau surfactants uas nws cov qauv molecular muaj ib lossis ntau qhov chaw them nqi zoo thiab tsis zoo (lossis cov chaw dipole) txuas nrog cov saw txuas (hydrocarbon chains, fluorocarbon chains, thiab lwm yam).
Nws yog ib qho me me surfactant. Tsis zoo li ib qho anionic lossis cationic surfactants, amphoteric surfactant molecules muaj cov kua qaub thiab cov pab pawg hauv ib qho kawg ntawm cov molecule. Cov pab pawg acidic feem ntau yog carboxyl, sulfonic acid, lossis phosphate pawg, thaum cov pab pawg hauv paus yog ib pawg amino lossis quaternary ammonium. Lawv tuaj yeem ua rau miscible nrog anionic thiab nonionic surfactants thiab tiv taus acids, alkalis, ntsev, thiab alkaline ntiaj teb hlau ntsev.
Lecithin nyob rau hauv qe yolks yog ib tug natural amphoteric surfactant. Tam sim no feem ntau siv hluavtaws amphoteric surfactants feem ntau muaj pawg carboxylic acid raws li lawv cov anionic moiety, nrog ob peb muaj sulfonic acid pawg. Feem ntau ntawm cov surfactants no muaj cationic moieties uas yog amine lossis quaternary ammonium ntsev. Cov uas muaj amine ntsev tsim cov cationic moieties hu ua amino acid hom; cov uas muaj quaternary ammonium ntsev tsim cov cationic moieties hu ua betaine hom.
Tag nrho peb hom surfactants tau yooj yim degraded nyob rau hauv aerobic tej yam kev mob, thaum amide betaine thiab amphoteric imidazolines tseem tau yooj yim degraded nyob rau hauv anaerobic tej yam kev mob. Kev tshawb fawb tshuaj lom ntawm Cyclocarya paliurus thiab Daphnia magna tau pom tias ib nrab ntawm - qhov siab tshaj plaws inhibitory concentrations (EC50) ntawm tag nrho peb hom surfactants siab dua 5 mg / L. Lub EC50 ntawm amphoteric imidazoline surfactants nyob rau hauv thaj tsam ntawm 20 mg / L txog 200 mg / L, qhia tias qis toxicity rau cov kab mob hauv dej.
