Supporting Information

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Patience Palmer
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1 Electronic Supplementary Material (ESI) for RSC Advances. This journal is The Royal Society of Chemistry 214 Supporting Information Theory: The physical properties of inary mixtures in different mass fractions (w n =.1,.3,.5, where n=1, 2 for α- and β-cd respectively) of aqueous α- and β-cd solutions at K has een reported in Tale S1. The experimental measured values of density, viscosity, refractive index of chosen three α-amino acids (i.e., L-Lys, L-Phe, L-Glu) in different mass fractions of aqueous α- and β-cd mixture, as a function of concentration (molarity) has een listed in Tale S2. Surface tension The concentrations at which the inclusion occurred (the reak point of the surface tension) have een calculated y solving the equation of two straight lines, and represented in Tale 1. For instance, in case of lysine in w 1 =.1 mass fraction of α-cyclodextrin γ = c γ = c γ = and c =.364. Apparent molar volume The apparent molar volumes V were determined from the solutions densities using the equation and given in Tale S3. V M / 1 / m (1) where M is the molar mass of the amino acids, m is the molality of the solution, and are the density of the solution and aq. α- and β-cd mixture respectively. The limiting apparent molar volumes V were otained y a least-square treatment to the plots of versus m using the Masson equation 1 V and shown in Tale S4. * V V SV m The standard deviations (σ) were determined using the following equation: 2 (Yexp Y os) / (N 1) where N is the numer of data points. (2) (3)

2 Contriutions of the zwitterionic end group, CH 2 groups and other alkyl chains of the amino acids to The V V value of zwitterionic end group and methylene group, and other alkyl chain of the amino acids were estimated from V V 3 n c V 2 (NH, COO ) (CH ) V ( R ) (NH V V 3, COO ) V (CH) V ( R ) V V 3 V V 2 (NH, COO ) (CH) (CH ) (4) (5) (6) Hydration Numer estimated from apparent molar volume The numer of water molecules (n H ) hydrated to amino acids can e estimated from the value of measured standard partial molar volume. The values of can e expressed as 2 (amino acid) (int) (elect) (7) V V V V of studied amino acids here (int) is intrinsic partial molar volumes of amino acids and (elect) is electrostriction V partial molar volume as a result of hydration of amino acids. The V (int) consists of two terms: van der Waals volume and volume due to packing effects. The values of V (int) for the amino acids were calculated from their crystal molar volume y 2 using the following relationship, V (int) V V = (.7.634) (cryst) (8) where,.7 is the packing density in an organic crystal and.634 is the packing density of randomly packed spheres. The molar volume of crystals V (cryst) was calculated using the crystal densities of the amino acids represented y Berlin and Pallansch. 3 The hydration numers is estimated using the relation H V (elect) ( e ) n / V V where is the molar volume of the electrostricted water and is the molar volume of ulk V e water. This model implies that for every water molecules taken from the ulk phase to the surroundings of amino acid, the volume is decreased y ( V V ). The value of ( V V ) is calculated 2 to e -3. or -3.3, at K respectively. The otained n H values are listed in Tale S6. e V (9) e

3 Viscosity The experimental viscosity data for the studied systems are listed in Tale S2. The relative viscosity (η r ) has een analyzed using the Jones-Dole equation 4 (/ o - 1)/ m = (η r - 1)/ m = A + B m (1) where η r =/ o, and are the relative viscosities, the viscosities of the ternary solutions (amino acid + aq. β-cd) and inary aqueous mixture (aq. β-cd) and m is the molality of the amino acids in ternary solutions. A and B are empirical constants known as viscosity A- and B- coefficients, which are specific to solute-solute and solute-solvent interactions, respectively, are estimated y least-square method y plotting ( 1) / m against m, and reported in Tale S4. The B-coefficients of zwitterionic group B(NH 3+, COO - ), the methylene group B(CH 2 ), and other alkyl group have een resolved as follows B = B(NH 3+,COO - ) + n c B(CH 2 ) (11) B(R) = B- (NH 3+,COO - ) -B(CH) (12) B(R) = B(NH 3+,COO - ) +-B(CH) - B(CH 2 ) (13) r Refractive index The molar refraction, R can e evaluated from the Lorentz-Lorenz relation 5 M 2 2 M D D R = (n -1)/(n + 2) (M/ ) where R, n, M and are the molar refraction, the refractive index, the molar mass and the M D density of solution respectively. The Limiting molar refraction ( R ) estimated from the following, 6 M (14) R R R m M M S (15) References: 1. D. O. Masson, Phil Mag., 1929, 8, F. J. Millero, A. L. Surdo and C. Shin, J. Phys. Chem., 1978, 82, E. Berlin and M. J. Pallansch, J. Phys. Chem., 1968, 72, G. Jones and D. Dole, J. Am. Chem. Soc., 1929, 51, V. Minkin, O. Osipov and Y. Zhdanov, Dipole Moments in Organic Chemistry. New York, Plenum Press, M. N. Roy, P. Chakraorti and D. Ekka, Mol. Phys., 214, In Press,

4 Tales: Tale S1: Experimental values of density(ρ), viscosity (η), refractive index (n D ), surface tension (γ), ph in deferent mass fraction of aqueous α- and β-cyclodextrin mixtures at K a ρ 1-3 η Aq. solvent mixture /kg m -3 /mp s aq. α-cd n D γ ph /mn m -1 w 1 = w 1 = w 1 = aq. β-cd w 2 = w 2 = w 2 = a Standard uncertainties u are: u(ρ) =5 1-5 g cm -3, u(η) =.3 mp s, u(n D ) =.2, u(γ) =.3 mn m -1, u(ph) =.1, and u(t) =.1K Tale S2: Experimental values of density (ρ), viscosity (η), refractive index (n D ), and ph of selected amino acids in deferent mass fraction of aqueous α- and β-cyclodextrin mixtures at K a molality /mol kg -1 ρ 1-3 /kg m -3 η /mp s Glysine n D molality ph ρ 1-3 η /mol kg -1 /kg m -3 /mp s L-Lysine n D ph

5 L-Phenylalanine L-Glutamic acid Glysine L-Lysine

6 L-Phenylalanine L-Glutamic acid

7 a Standard uncertainties u are: u(ρ) =5 1-5 kg m -3, u(η) =.3 mp s, u(n D ) =.2, u(ph) =.1, and u(t) =.1K w 1 and w 2 are mass fractions of α- and β-cyclodextrin in aqueous mixture respectively Tale S3: Apparent molar volume (ϕ V ), (η r -1)/ m, and molar refraction (R M ) of selected amino acids in different mass fraction of aqueous α- and β-cyclodextrin mixtures at K a Aq. solvent mixture ϕ V 1-6 (η r -1)/ m /m 3 mol -1 /kg 1/2 mol -1/2 Glysine R M Aq. solvent /m 3 mol -1 mixture ϕ V 1-6 (η r -1)/ m / m 3 mol -1 /kg 1/2 mol -1/2 L-Lysine R M /m 3 mol

8 L-Phenylalanine L-Glutamic acid Glysine L-Lysine

9 L-Phenylalanine L-Glutamic acid a Standard uncertainties u are: u(t) =.1K w 1 and w 2 are mass fractions of α- and β-cyclodextrin in aqueous mixture respectively

10 sol. mix Tale S4: Limiting apparent molar volume (ϕ V ), experimental slope (S V* ), viscosity A- and B-coefficient, and limiting molar refraction (R MO ) of selected amino acids in different mass fraction of aqueous α- and β-cyclodextrin mixtures at K a ϕ V /m 3 mol -1 S V * /m3 mol- 3/2 kg 1/2 B /kg 1/2 mol -1/2 S V * A R O M /kg mol -1 /m 3 mol sol. mix ϕ V /m 3 mol- -1 /m 3 mol -1 L-Lysine B /kg 1/2 3/2 kg 1/2 mol -1/2 A R O M /kg mol -1 /m 3 mol L-Phenylalanine L-Glutamic acid a Standard uncertainties u are: u(t) =.1K w 1 and w 2 are mass fractions of α- and β-cyclodextrin in aqueous mixture respectively

Chapter 4 Study of solute-solute and solute-solvent interactions of l-histidine in aqueous-sucrose solutions at different temperatures using

Chapter 4 Study of solute-solute and solute-solvent interactions of l-histidine in aqueous-sucrose solutions at different temperatures using Study of solute-solute and solute-solvent interactions of l-histidine in aqueous-sucrose solutions at different temperatures using volumetric, ultrasonic and viscometric methods 4.1. INTRODUCTION The physicochemical