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Kelsey Sneddon Chem 4101 December 8, 2010

Determination of Possible Compounds Causing Stains in Clothing and on Hands after Wearing a Sousaphone. Kelsey Sneddon Chem 4101 December 8, 2010. Hypothesis. Hypothesis. Importance of Solving Problem.

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Kelsey Sneddon Chem 4101 December 8, 2010

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  1. Determination of Possible Compounds Causing Stains in Clothing and on Hands after Wearing a Sousaphone Kelsey Sneddon Chem 4101 December 8, 2010

  2. Hypothesis Hypothesis Importance of Solving Problem • The reason hands and gloves/clothing develop a blue-green stain after coming in contact with a sousaphone after a marching band event is due to a compound being created in a reaction between the brass in the sousaphone and sweat; copper and/or zinc chloride compounds are the most likely species responsible for the stains. • Using an analytical method to determine possible compounds that develop stains on hands and clothing after being in contact with a sousaphone could lead to the basis for a proposition to Yamaha to find/create a coating that would prevent the reactions that cause the stains from occurring, thus eliminating the stains; this would allow for the sousaphone players to receive no irritation from playing and not ruin clothing while maintaining the good tone and sound quality a brass sousaphone offers.

  3. Background of Matrices and Analytes • Yellow Brass:The brass that the Yamaha YSH-411 brass sousaphone is made from9. Brass is considered a intermetallic compound where melts of metal mixtures, in this case copper and zinc, solidify1. Typically 33% Zinc and 67% Copper. (References 7 and 8). • Sweat: fluid composed mainly of water that is excreted from the body; some common compounds found in sweat include vitamins, chloride, lactate, and urea. The concentration of these compounds depends on location in the body and individuals2. • Copper(II) chloride/CuCl2:MW 134.45; mp 620°C. Upon addition of water becomes cupric chloride dihydrate/CuCl2 · 2H2O which then has a MW 170.48 and mp 100°C. Can cause skin irritation and is toxic to aquatic life3 and is blue-green in color. • Zinc chloride/ZnCl2: MW136.30; mp 293°C; highly soluble in water and can cause skin burns3. Upon addition of water becomes a dihydrate, but no scientific data could be found.

  4. Key Points/Theory • Techniques were evaluated with the idea that ideally the technique could analyze the concentration of copper and zinc in the brass, the concentration of compounds in sweat (specifically chloride), and the possible stain causing compounds CuCl2 and ZnCl2. • It became apparent that zinc chloride is not a compound directly responsible for the stain because no skin burns have ever been noted in the band; it remained in analytes to see if there is a possibility that under certain conditions it could be formed. • Since it would be difficult to obtain samples of the stain directly from hands and clothing, the environment of brass and sweat would have to be recreated in lab. • No information/data was found directly relating to this problem. • Ion chromatography: A form of LC that is used to separate and determine ions on columns with relatively low ion-exchange capacity4. • Ion-exchange processes are based on exchange equilibria betweens ions in solution and of ions of like charge on the surface of a solid on the column4; different resins for cation-exchange and anion-exchange. • Two Types of packings: polymetric bead packing where the bead surface is coated with an ion-exchange resin and the second is made by coating porous microparticles of silica with a film of exchanger4. • Introduction of eluent suppression column solved the problem of high conductance of eluents when using a conductivity detector with ion chromatography4. • Cation-Exchange Equilibria: • xRSO3-H+ + Mx+ (RSO3-)xMx+ + xH+ • Anion-Exchange Equilibria: • xRN(CH3)3OH+ + Ax- [(RNCH3+)3]xAx- + xOH+

  5. Possible Analytical Techniques

  6. Method of Choice: Ion-Chromatography/Conductivity • Low Mass LOD: 100pg-1ng • Adequate Linear Range 5 (decades) • Good reproducibility • Diverse enough to be able to analyze sweat, brass if derivatized to ions, and CuCl2 and ZnCl2 if in solution • Detector allows for high sensitivity • Detector universal for charged species • Allows for separation and then identification of components • Low cost per analysis • One detector for two separate columns (cation-exchange and anion-exchange columns) • High reliability • Low noise

  7. ICS-2100 Instrument (image courtesy of Arriaga Lecture 25 slide 5) Ion-Chromatography System Diagram (image courtesy of DIONEX.com-ICS-2100 series) (image courtesy of DIONEX.com-ICS-2100 series)

  8. Instrumentation

  9. Experimental Design • To begin standards of CuCl2, CuCl2 · 2H2O, and ZnCl2 would be acquired from Sigma Aldrich; cupric chloride, zinc chloride, and cupric chloride dihydrate in their powdered forms would be dissolved in water6 and injected seperately into ICS-2100 for analysis to be used for comparison/standard. These would be run in cation-exchange eluents and column. • Sweat samples would need to be collected from two male and two female ages 18-24 from the back and hands (Two samples per location per gender). These samples would be run separately and in anion-exchange eluents and column. • Obtain samples of yellow brass from local scrap metal garages, preferably including the brass used by Yamaha although unlikely; a small amount (less than a gram) of the brass would need to be added to excess sulfonic acid (20mL) with a stir/hot plate and allowed to dissolve. This mixture could then be injected into the ICS-2100 with cation-exchange eluent and column obtaining a spectrum to determine concentration of copper and zinc. • Once standards had been determined a small amount of brass would be added to excess sweat samples (20mL) with a stir/hot plate (temp would be near body temperature) to recreate the environment in which the stains are created. After dissolved enter newly created sample into ion-chromatography for analysis with both cation and anion-exchange eluents and columns respectively.

  10. Suggested Data Analysis • Chloride will have a retention time between 5 and 10 minutes; Copper will have a retention near 6; Zinc will have a retention time near 8 minutes. • Columns of 4x250mm • Determine amount of copper, zinc, and chloride by analyzing area of peaks created from samples discussed in previous slide. • Confirm results with standards to identify if analytes are present for proposed stain causing compounds • Look at chromatograms created to see if other species are present in sweat/brass samples for possible leads on other compounds causing stains.

  11. Conclusion • Brass interacting with sweat from the body causes stains to form on hands and clothing • Most likely responsible compound is cupric chloride dihydrate which can cause irritation in addition to blue-green stain. • A method to analyze the compounds created by brass interacting with sweat can be analyzed via ion-chromatography with a conductivity detector; other methods described would be less accurate and not be able to detect both metal compounds and chloride from brass, sweat, or reaction environment samples. • Solution of the stain causing compound(s) could lead to the creation of a coating preventing the reaction

  12. References • Housecroft, Catherine E. and Alan G. Sharpe (2008). Inorganic Chemistry (3rded). Harlow, England: Pearson/Prentice Hall. • Mickelson Olaf and Ancel Keys. 1943. The Composition Of Sweat, With Special Reference To The Vitamins*. J. Biol. Chem. 149, 479-490. • (2010). Sigma Aldrich. Retrieved 6 Dec 2010, from http://www.sigmaaldrich.com/technical-service-home/product-catalog.html • Skoog, Douglas A., F. James Holler, and Stanley R. Crouch (2007). Principles of Instrumental Analysis (6thed). Australia: Thomson Brooks/Cole. • (2010). Products. DIONEX. Retrieved 28 November/6 December 2010, from http://www.dionex.com/en-us/products/ion-chromatography/ic-rfic-systems/ics-2100/lp-72593.html. • O’Neil Maryadele J, Patricia E. Heckelman, Cherie B. Koch, Kristin J. Roman (2006). The Merck Index: An Enclyclopedia of Chemicals, Drugs, and Biologicals (14thed). Whitehouse Station, NJ: Merck & Co., Inc. • Twarog, D. L. 2000. Copper Alloys, Cast Copper Alloys. Kirk-Othmer Encyclopedia of Chemical Technology. • Goodwin, F. E. 2006. Zinc and Zinc Alloys. Kirk-Othmer Encyclopedia of Chemical Technology. • (15 June 2007 )YSH-411: Brass Sousaphone. YAMAHA CORPORATION OF AMERICA. Retrieved 12 September 2010, from http://www.yamaha.com/yamahavgn/CDA/ContentDetail/ModelSeriesDetail.html?CNTID=874&CNTYP=PRODUCT.

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