Masu hawan jini (bipolar surfactants) su ne masu hawan jini (surfactants) waɗanda ke da ƙungiyoyin anionic da cationic hydrophilic.

A takaice dai, amphoteric surfactants sune mahaɗan da ke da kowace ƙungiya biyu ta hydrophilic a cikin kwayar halitta ɗaya, gami da ƙungiyoyin anionic, cationic, da nonionic hydrophilic. Amphoteric surfactants da aka fi amfani da su galibi ƙungiyoyi ne na hydrophilic tare da ammonium ko quaternary ammonium gishiri a cikin ɓangaren cationic da nau'ikan carboxylate, sulfonate, da phosphate a cikin ɓangaren anionic. Misali, amino acid amphoteric surfactants tare da amino da ƙungiyoyin sashi a cikin kwayar halitta ɗaya sune betaine amphoteric surfactants da aka yi daga gishirin ciki wanda ke ɗauke da ƙungiyoyin quaternary ammonium da carboxyl, tare da nau'ikan iri-iri.

Nunin amphiphilic surfactants ya bambanta dangane da ƙimar pH na maganin su.

Nuna halayen cationic surfactants a cikin kafofin watsa labarai na acidic; Nuna halayen anionic surfactants a cikin kafofin watsa labarai na alkaline; Nuna halayen non-ionic surfactants a cikin kafofin watsa labarai na tsaka tsaki. Wurin da halayen cationic da anionic suka daidaita daidai ana kiransa da wurin isoelectric.

A wurin isoelectric, amino acid amphoteric surfactants wani lokacin suna zubewa, yayin da betaine surfactants ba sa zubewa cikin sauƙi ko da a wurin isoelectric.

Nau'in BetaineDa farko an rarraba surfactants a matsayin mahadi na gishirin ammonium na quaternary, amma ba kamar gishirin ammonium na quaternary ba, ba su da anions.
Betaine yana kula da cajin kwayoyin halitta mai kyau da kuma halayen cationic a cikin kafofin acidic da alkaline. Wannan nau'in surfactant ba zai iya samun caji mai kyau ko mara kyau ba. Dangane da ƙimar pH na ruwan maganin wannan nau'in mahaɗin, yana da kyau a rarraba shi a matsayin amphoteric surfactant ba daidai ba.

A bisa ga wannan hujja, ya kamata a rarraba mahaɗan nau'in betaine a matsayin cationic surfactants. Duk da waɗannan hujjoji, yawancin masu amfani da mahaɗan betaine suna ci gaba da rarraba su a matsayin mahaɗan amphoteric. A cikin kewayon heteroelectricity, akwai tsarin biphasic a cikin ayyukan saman: R-N+(CH3) 2-CH2-COO -.

Misali mafi yawan nau'in betaine shine alkyl.betaine, kuma samfurin da yake wakilta shine N-dodecyl-N, N-dimethyl-N-carboxyl betaine [BS-12, Cl2H25-N+(CH3) 2-CH2COO -]. Betaine tare da ƙungiyoyin amide [Cl2H25 a cikin tsarin an maye gurbinsa da R-CONH - (CH2) 3-] yana da kyakkyawan aiki.

Taurin ruwa ba ya shafar ingancin ruwabetaineSurfactant. Yana samar da kumfa mai kyau da kwanciyar hankali mai kyau a cikin ruwa mai laushi da mai tauri. Baya ga haɗa shi da mahadi anionic a ƙananan ƙimar pH, ana iya amfani da shi tare da surfactants anionic da cationic. Ta hanyar haɗa betaine da surfactants anionic, ana iya cimma cikakkiyar danko.