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Creating an Ion&Molecular Sensor By Combining Phenyl Mercaptoacetamide&Benzyl Mercaptoacetamide Ligands with Preferable Metals,Submitted by:Chris RocaMentor:Duncan Quarless,Ph.D.Undergraduate Asst.Mentor:Alicia Bowen,ABSTRACT,Phenyl mercaptoacetamide(PMA)&Benzyl mercaptoacetamide(BMA)were synthesized to observe their imitative relevance for fabricating the structure and reactivity of metallocysteinate proteins that are involved in metal transport.These ligands were used to observe if the type of reaction that takes place between them and the metal cations,which are Zinc(Zn2+)and Cobalt(Co2+),can produce an ion detecting molecule.Xylenol Orange was used as a color indicator to determine the extinction(metal concentration dependence)which is used from Beers law A=EBC and examine the visible spectroscopy of the various solutions,which determines the relative concentration of complexed and free indicators.Although no major results are yet found,zinc appears to be the least discriminate of the metal cations with respect to xylenol orange.Cobalt showed a lower extinction than Zinc which meant more concentration was needed than Zinc.The purpose of such an experiment is to see if these ligands can be an alternative for ion detection when combined with a metal,which for the moment seems to be Zinc.,INTRODUCTION,Ion recognition continues to be a major research goal for many supramolecular chemist groups around the world.Phenyl mercaptoacetamide(PMA)&Benzyl mercaptoactamide(BMA)are ligands or in other words they are a molecule that bonds to the central metal atom of a compound.What is expected to happen is that the ligands,BMA and PMA,would react with the metals,Zinc(Zn)and Cobalt(Co),to form a molecule that detects specific ions when the two come into contact.If successful this experiment can help produce an ion detecting agent that is a novel sulfur based ligand,and these assays will likely have relevance in analytical,environmental chemistry,as well as biomedical imaging and drug discovery.,MATERIALS,CHEMICALSAnilineBenzylamineThioglycolic acid(mercaptoacetic acid)Cobalt acetateZinc acetatepH 5 bufferMethanolLAB EQUIPMENTThermometersWeighing scalesAssorted glassware(Volumetric flasks,Erlenmeyer flasks,Buchner funnels,etc)Ultra violet Light(UV/vis)spectrophotometerInfrared(IR)spectroscopy apparatusNuclear Magnetic Resonance(NMR)Spectroscopy apparatus,SYNTHESIS OF BMA&PMA,Benzyl Mercaptoacetamide,Phenyl Mercaptoacetamide,METHODS,BMA&PMA were synthesized from benzyl amine and aniline,respectivelySamples were recrystallized from methanolChecked melting point of samplesTested purity of samples using GC-MS(gas chromatograph with mass spectrophotometer)Created pH 5 buffer for use in metal reactionsCreated metal solutions using zinc acetate and cobalt acetate in methanolXylenol Orange indicator was added to metal solutions which were then tested in uv/vis spectrophotometer to determine the extinction coefficients for metal xylenol orange complexesTested BMA&PMA using 1H NMR(nuclear magnetic resonance)to test the purity of solutions,and to characterize the compoundsTested for impurities and characterization using infrared spectroscopy,Rotating Around the Carbon-Amide Bond,RESULTS,No major results yet foundIn the UV/vis spectrophotometer Zinc was shown to have a more drastic extinction pattern in XO than Cobalt did in XOZinc is a better candidate than Cobalt for such an experimentImpurities were seen in the BMA&PMA when tested using IR spectroscopyThe NMR machine is currently malfunctioning,therefore,our samples have yet to be tested,FUTURE WORKS,Other metals will be tested as well such as Copper(Cu2+),Lead(Pb2+),and Mercury(Hg2+)The NMR machine will be finally used soon,so we can test magnetic resonance with BMA&PMAA better synthesis of PMA&BMA to try to make them 100%pure,REFERENCES,Conradie,J;Quarless,D.A;Hsu,H-F;Harrop,T.C;Lippard,S.J;Koch,S.A;Ghosh,A“Electronic structure and FeNO conformation of nonheme iron-thiolate-NO complexes:A combined experimental and DFT study,”J.Am.Chem.Soc.2007,(in press).Morlok,M M;Janak,K E;Zhu,G;Quarless,D A;Parkin,G“Intramolecular N-H.S Hydrogen Bonding in the Zinc Thiolate Complex(TmPh)ZnSCH2C(O)NHPh:A Mechanistic Investigation of Thiolate Alkylation as Probed by Kinetics Studies and by Kinetic Isotope Effects,”J.Am.Chem.Soc.2005,127,14039.Parkin,G.;Morlok,M.M.;Janak,K.E.;Melnick,J.G.;Zhu,G.;Docrat,A.;Quarless,Jr.,D.A.,“Chalcogenolate complexes of zinc in a sulfur rich coordination environment employing tris(2-mercaptoimidazolyl)hydroborato ligation,TmRZnEX(E=O,S,Se,Te):Synthetic analogues for modeling the mechanism of action of the Ada DNA repair protein,”Inorganic Paper 84,229th National Meeting of the American Chemical Society,San Diego,CA;March 2005.Quarless,D.A.;Bridgewater,B.M.;Parkin,G.“Tris(mercaptoimidazolyl)hydroborato zinc mercaptoacetamides:ligand exchange and methyl group transfer.”Poster Presentation,Gordon Inorganic Conference.Newport,RI 2002.Bhandari,C.s.Infrared and NMR Spectral Studies of Mercaptoacetamides.Bulletin De Acadenie Polonaise Des Sciences.Serie Des Sciences Chimiques 20(1972):91-100.Bhandari,C.s.Preparation and Electronic Spectra of Mercaptoacetamides.Journal Fur Praktische Chemie 313(1971):849-854.Abstract.Journal Fur Praktische Chemie 313(1971):5.Giles,Niroshini M.,Aaron B.Watts,Jennifer A.Littlechild,Gregory I.Giles,Fiona H.Fry,and Claus Jacob.Metal and Redox Modulation of Cysteine Protein Function.Chemistry&Biology 10(2003):677-693.Luo,Chunling,Zhenguo Shen,Xiangdong Li,and Alan J.M.Baker.Enhanced Phytoextraction of Pb and Other Metals From Artificially Contaminated Soils Through the Combined Application of EDTA and EDDS.Chemosphere 63(2006):1773-1784.Machi,Lorena,Hisila Santacruz,Mario Sanchez,and Motomichi Inoue.Cd2+Sensiting Bichromophore:Excimer Emission From an EDTA-Methylnaphthalene Derivative.Inorganic Chemistry Communications 10(2007):547-550.Nayak,Manoj K.,Jangwon Seo,Sanghyuk Park,and Soo Young Park.Colorimetric and Highly Selective Turn-on Fluorescent Anion Chemosensors with Excited State Proton Transfer.Journal of Photochemistry and Photobiology(2007).,ACKNOWLEDGEMENTS,Mr.Edward IrwinDuncan Quarless,Ph.D.Alicia BowenDr.Sat BattacheryaHCS Staff,