Effect of Atenolol on the Interaction between Direct Red 16 or Direct Orange 26 and TTAB

A simple, low-cost and sensitive method has been used to investigate the interaction between a cationic surfactant, tetradecyltrimethylammonium bromide (TTAB), two anionic dyes, C.I. Direct Orange 26 (DO26) and C.I. Direct Red 16 (DR16), and a drug, Atenolol (ATN). The methods used to study the interaction were electromotive force (EMF) measurements involving a surfactant–selective electrode and spectrophotometry. This method was also used to investigate the interactions of Atenolol (ATN). The interaction between TTAB and DO26 was found to be stronger than that of TTAB and DR16. TTAB only showed a weak interaction with ATN at a high drug concentration. Therefore, when ATN was added to a mixture of TTAB and the dye, ATN was found to first interact with the dye and, when ATN saturated, a higher concentration of TTAB interacted with the dye.