Physicochemical studies of globular proteins—Bovine serum albumin, egg albumin, and lysozyme—In some aqueous iodide salts solutions of IA group and cetyltrimethyl ammonium bromide systems

Densities (ρ, kg m⁻³), and viscosities (η, 0.1 kg m⁻¹ s⁻¹) of Bovine Serum Albumin (BSA), Egg Albumin, and Lysozyme in aqueous iodide salts of lithium, sodium, and potassium, along with cationic surfactant-cetyltrimethyl ammonium bromide (CTAB) were measured at a temperature of 303.15 K. The 0.0010–0.0018 g %, w/v of each protein at an interval of 0.0002 mol L⁻¹ in 0.2, 0.4, and 0.8 millimol L⁻¹ of salt and CTAB are studied. Data are used for apparent molar volumes (V_ϕ, 10⁻⁶ m³ mol⁻¹) and intrinsic viscosities ([η], dL kg⁻¹), respectively. Data are regressed and extrapolated to zero concentrations for ρ⁰, η⁰, and limiting values and S_d, S_η and S_V corresponding slopes for protein–salt structural interactions. With size of cations, the densities decrease as CTAB > LiI > NaI > KI and increase with salts concentrations, with salts the densities are as Lysozyme > BSA > Egg Albumin, viscosities and V_ϕ as BSA > Egg–Albumin > Lysozyme. The ρ and η values with CTAB higher and [η] are lower and converse at around 0.4 mmol L⁻¹ salt and is effective for greater stability of proteins. The [η] in CTAB are higher than other salts and decreases with size of cations with stronger intermolecular forces. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008