مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 Density and Viscosity of Amino Acid Serine in Aqueous Dimethyl Sulfoxide Solution at Different Temperatures Z.A. AL-Dulaimy , Z. W. AL-Amel ,R. S. AL-Khalisy , Z. H. Hussein Department of Chemistry, College of Education Ibn-Al-Haitham University of Baghdad Received in : 23 August 2011 , Accepted in:10 November 2011 Abstract Densities  and viscosity  of serine in 20, 40, and 60% (w/w) dimethyl sulfoxide (DM SO)-water mixtures were measured at 298.15, 303.15 and 308.15k. From these experimental data, apparent molal volume v , limiting apparent molal volume v o , the slop vS , transfer volume v o(tr), Jones-Dole coefficients A and B were calculated. The results are v odiscussed the solute-solvent and solute-solute interaction, and showed that serine behaves as structure-breaker in aqueous DMSO solvent. Key word: Density, Viscosity , Amino Acid, Serine, dimethyl sulfoxide Introduction Amino acid which are the fundamental substances for building blocks of proteins are used as model compounds to study the interactions of proteins in water and different solutions. A number of workers studied the volumetric and viscometric properties of amino acids in water [1-3]. Ali and Shahjaham [4] studied the volumetric and viscometric behaviour of L- serine, L-threonime, L-glutamine, L-lysine, L-arginine and L-histidine amino acids and their group contributions in aqueous tetramethyl ammonium bromide at different temperatures. It is well known that the mixed aqueous solvents (with different percent w/w) can influence the solubility behavior of amino acids. Consequently thermodynamic properties, enthalpies, heat capacities, apparent molal volumes and viscosities of amino acids and peptide in mixed aqueous solvents are useful to obtain information about various types of interactions in these solutions [5-6]. Serine (abbreviated as Ser or S) [7], is an amino acid with the formula HO2CCH(NH2)CH2OH.. It is one of the proteinogenic amino acids. By virtue of the hydroxyl group, serine is classified as a polar amino acid. Patel and workers [8] demonstrate the interaction of some amino acids(L-serine, L- threonime, L-glutamine, L-lysine, L-arginine and L-histidine) in aqueous caffeine they got positive values of partial molal volume of transfer of amino acid from water to aqueous- مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 caffeine v o(tr) ( v o,caffeine- v o,water) which indicate the diminishing of electrostrictive effect of amino acids and addition of caffeine. They related the diminishing to shielding of the amino acids zwitterionic groups from water. The partial molar volumes of tranfere v o(tr) of amino acids from aqueous to aqueous tetramethyl ammonium bromide solution were interpreted in the light of cosphere overlap model. The cosphere overlap model [9] can be used for interpretation of negative v o(tr) values, according to which the overlap of two hydration spheres is destructive. HO - CH2 - C - COO NH3 H CH3 CH3 S O Serine (Ser) M= 105.1 g.mol -1 Dimethyl sulfoxide (DMSO) M=78.13 g.mol -1 In present work viscosities  and densities  of serine (0.1, 0.15, 0.20, 0.25, 0.30 and 0.35 molar concentration) were measured in 20, 40 and 60% (w/w) DM SO + water mixtures at 298.15, 303.15 and 308.15k. Then the apparent molal volumes v  , limiting molal volumes at infinite dilution v o, transfer volumes at infinite dilution v o(tr) and Jones-Dole coefficients B and D were calculated. Experimental Amino acid serine obtained from Fluka company is Analar and used without any further treatment. Dimet hyl sulfoxide (DMSO) is aprotic polar liquid with a high dielectric constant obtained from Fluka company (purity >99.7%) used without further purificat ion. Water used for preparation for all the solution doubly distilled (Sp.conductivity ~10-6 ohm- 1cm-1). T he serine concentrat ion in these mixt ures was ranged from( 0.1-0.35) mol.dm-3.The viscosity  were determined using a suspended-level ubbelohde viscometer described by findly [10], in a bath controlled to ±0.01K for all measurements. Densities  of all solutions were measured using a vibrating tube with digital Anton Parr densimeter (DM A 60/602) according to shuklu etal. Procedure[11], in athermostated bath controlled to ±0.01K. مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 . Results and Discussion The results of absolute viscosities  and densities  are listed in table 1. The apparent molal volume v  of serine in aqueous dimethyl sulfoxide (DM SO+H2O) is measured at 298.15, 303.15 and 308.15K using the following relation [12]. 3 31 10 10 [ ] .............(1)v m M m       o Where  and o are the densities of solution and solvent respectively, M is molecular weight of solute and m is the molality of solution. m is calculated using the following relation m=1/(P/C –M/103)where C is the molar concentration. The results of v are tabulated in table (1). Table (1) shows that the value of v decrease with the increase of concentration of serine but v increases with increasing DM SO% content and temperature increase in solution suggesting that the solute-solvent interaction increase with the increase of DMSO%. Since the limting apparent molal voiume v were obtained from the realation [13]. v v= .............(2)vS m  o Where the intercept v o, which is measure of solute-solvent interaction, and the experimental slop vS , which is aparameter of solute-solte interaction were obtained by the molality fitting of v values to eqution(2)in figure(1) and tabulated in table(2). Table 2 reveals that v oare positive and increase with the increase of temperature, indicating the presence of solute-solvent interactions. The increase in v oon going from 20% to 60% DMSO indicates the increasing trends of solute-solvent interaction. Table 2 shows that all the values of v S are negative pointing the presence of weak solute-solute interactions in solutions. Moreover, the values of v S become more negative with the increase of DM SO content suggesting decreasing in solute-solute interaction with DM SO-rich solvent. In fact negative v S values are often obtained in solvent of high dielectric constant such as (DMSO + Water Solvent) [14]. The transfer volumes v o(tr) of serine when transferred from water to (DM SO+Water) mixture solution are found using this equation: v o(tr) = v o(DM SO + Water) - v o, water مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 The values of v o, water for serine are 68.07, 66.28 and 65.28 cm3.mol-1 at 298.15, 303.15 and 308.15K respectively which are estimated from our previous work[15]. The v o(tr) results are listed in table (3). A perusal of table 3 indicates that v o of serine in mixed liquids (DM SO+ Water) are lower than those in pure water, v o(tr) values are negative for all solutions studied. It is known that zwitterionic groups of amino acids induce a considerable concentration in volume of peripheral solvent (water) due to electrostrictive effect ,which is diminished on addition of DM SO. Viscosity data were analyzed employing Jone-Dole equation [16]. ŋrel -1/ C =A+B C ………….(3) Where  and oare the viscosity of solution and solvent respectively, the Jones-Dole coefficient, A, reflects the effect of solute-solute interaction and B, is a measure of structural modifications induced by the solute-solvent interaction. The viscosity coefficient A and B were obtained from the intercept and slope of the plots ŋrel -1/ C against C . The values of A and B are listed in table (2). Table (2) shows that the values of A-coefficient are negative whereas those of B-coefficients are positive, suggesting weak solute-solute and strong solute- solvent interaction. The variation of B with T is depicted graphically in figure 1, revealed that the slope ( /B T  ) is positive for serine in 20, 40 and 60% DM SO content in solution, serine in all solutions act as structure-breakers[17]. Conclusions, the values coefficient A and B support the behaviors of v S and v o(tr) which all suggest stronger solute-solvent interactions as compared to solute-solute interactions. The positive ( /B T  ) values for all solutions which pointed that the serine acts as a structure-breaker when DMSO added to solutions. References 1. Frank, H.S. and Wen, W.Y.(1957) Ion-Solvent interaction strructual aspects of ion-solvent interaction in aqueous solution asuqqested picture of water structure. Discuss Faraday Soc., 24:133. 2. Tyrrell, H.J.V. and Kennerley, M. (1968)A, Viscosity B- coefficients between 5 o and 20o for glycolamide, glycine, and N- methylatde glycines in aqueous solution. J. Chem. Soc 90: 2724. 3. Devine, W. and Lowe, B.M.( 1971)A, Apparent molar volumes and viscosity B- coefficients of same α-amino acids in aqueous solutions from 278.15K to 308.15K 2113 J. chem.. Soc.. 4. A Ali A. and Shahjahan, Z.(2008)Volumetric and viscomitrc behavior of some amino acids and thir group contribution in aqueous tetramethyl ammonium bromide at different temperatures, phys. Chem. 222:1519. 5. Phangs , Aust. (1977) The viscosity of glycine and DL-alanine in dimethyl formamid- water mixtures at 298.15K, J. chem., 30:1605. 6. Prasad, K. P. and Ahluwalia, J. C. (1980)Biopolymers, Heat capacity changes and partial molal heat capacities of some and tripeptides in water, 19:263. مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 7. Λ "Nomencluture and Symbolism for amino acids and peptides (IUPAC-IUB Recommendations 1983)" Pure Appl. Chem., 56(5): 595-624, 1984. 8. Ali, A.; Sabir, S.; Nain, A.K.; Hgder, S.;Ahmed, S.;Tariq, M. and Patel, R. (2007) J. Chin. Chem. Soc., Interaction of phenylalanine , tyrosine and hitadine in aqueous caffeine solution at different temperatures, 54:659. 9. Friedman, H.L.; Krishnan, C.V.(1973)Water-Acomprehensive Treatise. F. Franks (Ed.), Plenumpress, New York, 10. Findly, A. " Practical Physical Chemistry", 8 th ed., J. A. Kitchrer (London: Longman), 1954. 11. James, A. M. and Prichard ,E. F. (1974) Practical physical chemistry, Wiley, New York. 12. Pal, A. and Kumar, S. ( 2005) Volumetric studies of some amino acids in binary aqueous solution of MgCl2.6H2O at 288.15 and 308.15K, T. Chem. Soc. 117 (3):267. 13. Hedwig, G.R. and Reading, J.(1991) Faraday Trans, Aqueous solutions containing amino acids and peptides part 27-partial molar heat capacities and partial molar volumes of some N-acetyl amino acids amides and tow peptides at 25 o C, J. Chem. Soc. 87:1751. 14. Ali, A, ;Nain, A.K.; Kumar, N. and Ibrahim, M.(2002)Densities viscosities of magnesium sulphate in formamide+ethylene glycol mixed solvents, Proc. Indian Acad. Sci. (Chem. Sci.) 114:495. 15. AL-Dulaimy, Z. A. H.;AL-Jawary, A. A.; AL- Saidi, S. F.(2009) Viscosity and volumetric studies of amino acids in solution at different temperatures, J. of Kerbala University 7:289-295 . 16. Jones, G.and Dole, M.(1929) The viscosity of aqueous solutions of strong electrolytes with special reference of strong electrolytes with special reference to barium chloride, J. AM . Chem. Soc., 51:2950. 17. Ali, A.; Hyder, S.; Sabir, S.; Chand, D.and Nain, A. K.(2006) Thermodyn., Volumatric, viscometric and refractive index behavior of α-amino acids and their groups , contribution in aqueous D-glucose solution at different temperatures J. Chem..38:136. مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 Table(2): Partial molal volume at infinite dilution v o, v S , Jones-Dole coefficients A and B of serine in various water + DMSO mixtures at different temperatures. 298.15k 303.15k 308.15k Solu. Ser. + H2O + 20% DMSO v ocm3.mol-1 59.41 58.803 59.925 v S cm3.mol-2kg -7.0466 -8.586 -10.482 A L1/2.mol-1/2 -0.3308 -0.3374 -0.3455 B L.mol-1 1.5051 1.5296 1.5900 Solu. Ser. + H2O + 40% DMSO v ocm3.mol-1 61.193 62.401 63.727 v S cm3.mol-2kg -10.606 -10.636 -11.306 A L1/2.mol-1/2 -0.3152 -0.3421 -0.3653 B L.mol-1 2.3072 2.6084 2.9695 Solu. Ser. + H2O + 60% DMSO v ocm3.mol-1 64.131 65.121 65.259 v S cm3.mol-2kg -11.508 -12.028 -12.441 A L1/2.mol-1/2 -0.3270 -0.3631 -0.3927 B L.mol-1 0.4727 2.9637 3.1620 مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 Table(3): Partial molal volumes of transfer at infinite dilution v o(tr) of serine from water to mixed liquid (DMSO + Water) at different temperatures. ( ) v tr o (cm3. mMol-1) Serine in mixed liquid (DMSO + Water) 298.15k 303.15k 308.15k 20% DMSO -8.660 -7.477 -5.355 40% DMSO -6.877 -3.879 -1.553 60% DMSO -3.930 -1.159 -0.021 20% DMSO 56 56.5 57 57.5 58 58.5 59 59.5 0 0.1 0.2 0.3 0.4 298.15 303.15 308.15 40% DMSO 57 58 59 60 61 62 63 0 0.1 0.2 0.3 0.4 m 298.15 303.15 308.15 V V m مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 60% DMSO 60 61 62 63 64 65 66 0 0.1 0.2 0.3 0.4 m 298.15 303.15 308.15 Against m for serine in various water+DMSO mixture at different V Fig.(1): temperature Fig. (2): B-coefficient verses T for serine in various water +DMSO mixtures 0 0.5 1 1.5 2 2.5 296 298 300 302 304 306 308 310 T B 20%DMSO 40%DMSO 60%DMSO V مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 دراسة لزوجیة وكثافة الحامض االمیني سیرین في المحلول المائي لداي مثیل سلفوكساید بدرجات حراریة مختلفة زینة حمودي حسین ، رقیة سمیر الخالصي ، زینب وجدي العامل ، زینب عباس الدلیمي بغداد جامعة، أبن الھیثم –كلیة التربیة ، قسم الكیمیاء 2011 تشرین الثاني 10: قبل البحث في 2011 آب23: استلم البحث في الخالصة (w/w)% 60، % 40، %20 محالیل الحامض االمیني سیرین في محالیل لتركیـز  ولزوجة قیست كثافة DMلداي مثیل مثیل سلفوكساید SO كلفن استخدمت هـذه النتـائج 298.15 , 303.15 , 308.15 بدرجات حراریة مختلفة والحجــم المــواللي الظـــاهري المحــدد vحجـــم المــواللي الظـــاهري فــي حــساب ال v o والمیـــل vS ـال ,(tr) حجــم االنتقـ v o .B , Aومعاملي جونس ودول مذاب وقد اظهرت النتائج ان السیرین یـسلك سـلوك - مذیب ومذاب-تمت مناقشة طبیعة التداخالت من نوع مذاب . سلفوكسایدمهدم للتركیب في المحالیل المائیة لداي مثیل . داي مثل سلفوكساید، السیرین، الحوامض االمینیة، اللزوجة، الكثافة:الكلمات المفتاحیة مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 Table (1): Densities (ρ) and Viscosities (η) with calculated apparent molal volume ( v ), and the (ŋrel -1/ C ) of serine in water at different percent (w/w) of dimethyl sulfoxide mixtures at different temperatures. 20% 40% C mol.dm- 3 C m mol.kg- 1 ρ g.cm-3 η cp v cm3.mol- 1 ŋrel - 1/ C m mol.kg- 1 ρ g.cm-3 η cp v cm3.mol- 1 ŋrel - 1/ C m mol.kg 1 0.00 0.0000 1.0582 1.0838 0.0000 1.0595 1.1203 0.0000 0.1 0.3162 0.0950 1.0625 1.1403 58.6604 0.1642 0.0949 1.0636 1.2789 60.4768 0.4477 0.0929 0.15 0.3873 0.1430 1.0647 1.1820 58.3692 0.2339 0.1428 1.0658 1.3658 59.5420 0.5658 0.1419 0.2 0.4472 0.1912 1.0669 1.2433 58.2064 0.3291 0.1910 1.0680 1.4655 59.0794 0.6890 0.1898 0.25 0.5000 0.2397 1.0692 1.3125 57.7382 0.4220 0.2394 1.0703 1.5786 58.4142 0.8182 0.2378 0.3 0.5477 0.2886 1.0715 1.3819 57.4413 0.5022 0.2884 1.0726 1.6911 57.9882 0.9303 0.2863 0.35 0.5916 0.3374 1.0739 1.4450 56.9198 0.5633 0.3372 1.0748 1.8459 57.9407 1.0948 0.3350 298.15k 0.00 0.0000 1.0556 0.9889 0.0000 1.0546 1.0698 0.0000 0.1 0.3162 0.0953 1.0599 1.0365 58.8323 0.1522 0.0954 1.0586 1.2459 61.7253 1.6461 0.0950 0.15 0.3873 0.1435 1.0621 1.0877 58.5618 0.2579 0.1435 1.0608 1.3374 60.4553 1.6676 0.1430 0.2 0.4472 0.1917 1.0643 1.1365 58.3551 0.3337 0.1919 1.0629 1.4504 60.2946 1.7788 0.1913 مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012 0.25 0.5000 0.2403 1.0666 1.1977 57.8808 0.4228 0.2407 1.0651 1.5742 59.8395 1.8859 0.2399 0.3 0.5477 0.2891 1.0690 1.2610 57.2409 0.5024 0.2896 1.0673 1.7064 59.5111 1.9835 0.2888 0.35 0.5916 0.3383 1.0714 1.3250 56.8013 0.5744 0.3389 1.0697 1.8503 58.7552 2.0845 0.3379 303.15k 0.00 0.0000 1.0530 0.9869 0.0000 1.0533 1.0289 0.0000 0.1 0.3162 0.0955 1.0573 1.0360 58.9617 0.1520 0.0955 1.0572 1.2243 62.7404 1.8991 0.0952 0.15 0.3873 0.1437 1.0595 1.0901 58.6584 0.2699 0.1437 1.0593 1.3375 61.7946 1.9995 0.1433 0.2 0.4472 0.1922 1.0619 1.1499 57.5616 0.3693 0.1922 1.0614 1.4610 61.3237 2.0998 0.1917 0.25 0.5000 0.2409 1.0642 1.2064 57.2710 0.4448 0.2410 1.0635 1.5947 61.0424 2.1996 0.2403 0.3 0.5477 0.2893 1.0665 1.2699 57.0667 0.5236 0.2901 1.0656 1.7388 60.8546 2.2997 0.2893 0.35 0.5916 0.3391 1.0690 1.3360 56.3999 0.5979 0.3394 1.0682 1.8931 59.3639 2.3997 0.3389 308.15k مجلة إبن الھیثم للعلوم الصرفة و التطبیقیة 2012 السنة 25 المجلد 1 العدد Ibn Al-Haitham Journal for Pure and Applied Science No. 1 Vol. 25 Year 2012