Sodium anilino naphthalene sulfonate

Abbreviations for amino acids and their derivatives follow the revised recommendation of the lUPAC-IUB Committee on Biochemical Nomenclature, entitled Nomenclature and Symbohsm for Amino Acids and Peptides (recommendations of 1983). Nomenclature of branched polypeptides is used in accordance with the recommended nomenclature of graft polymers (lUPAC-lUB recommendations, 1984). For the sake of brevity codes of branched polypeptides were constracted by us using the one-letter symbols of amino acids (Table 1). The abbreviations used in this paper are the following. AK, poly[Lys-(DL-Ala )] AXK, poly[Lys-(DL-Ala -Xi)] XAK, poly[Lys(Xi-DL-Ala )] X = Ser (SAK), Om (OAK), Glu (EAK), or Ac-Glu (Ac-EAK). All amino acids are of L-configuration unless otherwise stated. DPH, l,6-diphenyl-l,3,5-hexatriene ANS, sodium anilino naphthalene sulfonate DPPC, dipalmitoyl phosphatidyl choline PG, phosphatidyl glycerol Z, benzyloxycarbonyl Pep, pentachlorophenol P, polarisation. 

The effect of branched polypeptides on phospholipid membranes was further investigated using lipid bilayers with DPPC/PG (95/5, 80/20 mol/mol). Two fluorescent probes of different character were used to analyse the effect of polymers on the outer surface (negatively charged, sodium anilino naphthalene sulfonate, ANS) and on hydrophobic core (hydrophobic, l,6-diphenyl-l,3,5-hexatriene DPH) of bilayers. For these studies small imilamellar vesicles were used. 

Mixed surfactant systems can be investigated by the use of certain probes. Ultraviolet-visible spectra can provide information on the state of mixed micelles, the cmc value, and whether the interaction between different components in mixed micelles is taking place. Meguro and co-workers pioneered the use of this method to study the surfactant mixture system. In their extensive study, probes, tetracyanoquindimethane [55-58], benzoylacetone [59], beznoylacetoanilide [60,61], sodium (p-sulfonatophenylazo-l-naphthol-2-sulfonate) [62,63], and 8-anilino-naphthalene sulfonic ammonium salt [64] were examined. Using the probe method, Meguro and co-workers [64] confirmed the existence of mixed micelles between hydrocarbon-fluorocarbon surfactant, which was a controversial question before. 

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