A Cloud Point Study on the Micellar Growth of an Amphiphilic Drug in the Presence of Alcohol and Ionic Surfactant

Abstract

Cloud point (CP) measurements have been performed to investigate the influence of alcohols (C 2 -C 10 OH) on the micellar growth of amphiphilic drug amitriptyline (AMT) in the presence of salt and surfactant. In the case of shorter-chain alcohols (C 4 OH or C 5 OH), the CP increased with increasing alcohol concentration in the presence of a small amount of sodium phosphate because they partition very little in AMT micelles. On the other hand, it steeply decreased with increasing alcohol concentration in the case of longer-chain alcohols (C 8 OH or C 10 OH) due to their considerable partitioning in AMT micelles. The effect of hindering the micellar aggregation was enhanced as the alcohol chain length increased in the case of shorter-chain alcohols. The CP became less sensitive to addition of C 6 OH at higher sodium phosphate concentrations, resulting from incorporation of more C 6 OH molecules into the enlarged micelles. Addition of cationic surfactant cetylpyridinium chloride to the AMT micellar solutions increased the CP because cetylpyridinium cations affect electrostatic interactions with the cationic AMT headgroup, while addition of anionic surfactant, sodium dodecyl sulfate, decreased the CP because of penetration of dodecyl chains into the micelles, resulting in a micellar growth.

Physicochemical Interactions of Chlorpheniramine Maleate with Sodium Deoxycholate in Aqueous Solution

“…Mixed drug‐surfactant systems are commonly used to treat malignant disease and have led to an increase in the survival and quality of life due to their potential for exerting additive or synergistic effects (Borrego et al, ; Srivastava et al, ). Similar to surfactants, many drugs also aggregate at a specific concentration in an aqueous medium due to hydrophobic interactions (Alam et al, , , , , , , ; Alam and Mandal, ; Barbosa et al, ; Caetano et al, , ; Enache et al, ; Göktürk and Aslan, ; Göktürk and Var, , ; Hoque et al, ; Hossain and Hoque, ; Kabir‐ud‐Din et al, , , ; Kaushal et al, , ; Kim and Shah, , ; Kumar et al, ; Kumar and Rub, ; Mahajan et al, ; Mahajan and Mahajan, , ; Naqvi et al, ; Noori et al, ; Rub et al, , , , ; Schreier et al, ; Sharma et al, ; Sharma and Mahajan, ; Srivastava et al, ; Tiwary et al, ). Drug self‐association and strong binding behavior are important for pharmacological applications.…”

Effects of Cationic Surfactants on Clouding Action of the Drug Amitriptyline Hydrochloride in Ethylene Glycol-Water and Glycerol-Water Mixed Media

“…The drug used in this work is an antidepressant and the effects of cationic surfactants, both conventional hexadecyltrimethylammonium bromide (CTAB), tetradecyltrimethylammonium bromide (TTAB) and gemini (14‐4‐14, 14–5‐14 and 14–6‐14) on the CP in various compositions of ethylene glycol‐water (EG‐WR) and glycerol‐water (GL‐WR) mixed media at a pH 6.7 have been studied. It is pertinent to mention here that many works have been reported about the effect of additives on CP of AMT but all such studies have been performed in an aqueous solution ,,. A change in the characteristic of the medium, with addition of organic solvent into pure water, alters the cmc, rheological behavior, aggregate morphology and the thermodynamic parameters of surfactants .…”

“…It is pertinent to mention here that many works have been reported about the effect of additives on CP of AMT but all such studies have been performed in an 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 aqueous solution. [4,12,[17][18][19] A change in the characteristic of the medium, with addition of organic solvent into pure water, alters the cmc, rheological behavior, aggregate morphology and the thermodynamic parameters of surfactants. [20][21][22] Therefore, the focus of our study is to understand the effect of mixed media (organic solvent-water mixture) on clouding phenomena of amphiphilic molecules in the absence and presence of conventional/gemini surfactants.…”

Effects of pharmaceutical excipients on cloud points of amphiphilic drugs

“…Nonionic surfactants almost always and ionic surfactants and amphiphilic drugs in special conditions exhibit phase separation [13][14][15][16][17][18][19][20]. When aqueous solutions of these amphiphiles are heated to a certain temperature, they undergo phase separation or clouding.…”