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Chromatograms

  • Page ID
    285021
  • All Analgesics, 55% pH=7 0.025M phosphate buffer

    C18, Black Trace 245 nm, Green Trace 195nm
    C18_AllAnalgesics.png

    RP-Amide, Black Trace 245 nm, Green Trace 195nm
    RP-Amide_AllAnalgesics.png

    C18-PFP, Black Trace 245 nm, Green Trace 200nm
    C18-PFP_AllAnalgesics.png

    RP-Amide, 55% pH=5 0.025M phosphate buffer

    Mix A (order: aspirin and caffeine, salicyclamide, phenacetin),  Black Trace 245 nm, Green Trace 220nm
    MixA_RP-Amide_pH5.png

    Acetaminophen, Black Trace 245 nm, Green Trace 195nm
    Acetaminophen_RP-Amide_pH5.png

    Ibuprofen, Black Trace 245 nm, Green Trace 195nm
    Ibuprofen_RP-Amide_pH5.png

    Diphenhydramine, Black Trace 245 nm, Green Trace 195nm
    Diphenhydramine_RP-Amide_pH5.png

    All Analgesics, 195nm
    AllAnalgesics_RP-Amide_pH5.png

    RP-Amide, 55% pH=7 0.025M phosphate buffer

    Mix A, Black Trace 245 nm, Green Trace 220nm: aspirin, caffeine, salicyclamide, and phenacetin, respectively
    MixA_RP-Amide_pH7.png

    Acetaminophen, Black Trace 245 nm, Green Trace 195nm
    Acetaminophen_RP-Amide_pH7.png

    Ibuprofen, Black Trace 245 nm, Green Trace 195nm
    Ibuprofen_RP-Amide_pH7.png

    Diphenhydramine, Black Trace 245 nm, Green Trace 195nm
    Diphenhydramine_RP-Amide_pH7.png

    All Analgesics, Black Trace 245 nm, Green Trace 195nm
    AllAnalgesics_RP-Amide_pH7.png

    RP-Amide, 55% pH=9 0.025M phosphate buffer

    Mix A (order aspirin, caffeine and salicyclamide, phenacetin) Black Trace 245 nm, Green Trace 230nm
    MixA_RP-Amide_pH9.png

    Ibuprofen, Black Trace 245 nm, Green Trace 195nm
    Ibuprofen_RP-Amide_pH9.png

    Diphenhydramine, Black Trace 245 nm, Green Trace 195nm
    Diphenhydramine_RP-Amide_pH9.png

    All Analgesics, Black Trace 245 nm, Green Trace 200nm
    AllAnalgesics_RP-Amide_pH9.png

    C18-PFP, 55% pH=5 0.025M phosphate buffer

    Mix A (aspirin, caffeine, salicyclamide, phenacetin) Black Trace 245 nm, Green Trace 213nm
    MixA_C18-PFP_pH5.png

    Acetaminophen, Black Trace 245 nm, Green Trace 195nm
    Acetaminophen_C18-PFP_pH5.png

    Ibuprofen, Black Trace 245 nm, Green Trace 195nm
    Ibuprofen_C18-PFP_pH5.png

    Diphenhydramine, Black Trace 245 nm, Green Trace 195nm
    Diphenhydramine_C18-PFP_pH5.png

    All Analgesics, Black Trace 245 nm, Green Trace 195nm
    AllAnalgesics_C18-PFP_pH5.png

    C18-PFP, 55% pH=7 0.025M phosphate buffer

    Mix A (order aspirin, caffeine, salicyclamide, phenacetin), Black Trace 245 nm, Green Trace 225nm
    MixA_C18-PFP_pH7.png

    Acetaminophen, Black Trace 245 nm, Green Trace 195nm
    Acetaminophen_C18-PFP_pH7.png

    Ibuprofen, Black Trace 245 nm, Green Trace 195nm
    Ibuprofen_C18-PFP_pH7.png

    Diphenhydramine, Black Trace 245 nm, Green Trace 195nm
    Diphenhydramine_C18-PFP_pH7.png

    All Analgesics, Black Trace 245 nm, Green Trace 200nm
    AllAnalgesics_C18-PFP_pH7.png

    C18-PFP, 55% pH=9 0.025M phosphate buffer

    Mix A (order aspirin, caffeine and salicyclamide, and phenacetin) Black Trace 245 nm, Green Trace 210nm
    MixA_C18-PFP_pH9.png

    Ibuprofen, Black Trace 245 nm, Green Trace 195nm
    Ibuprofen_C18-PFP_pH9.png

    Diphenhydramine, Black Trace 245 nm, Green Trace 195nm
    Diphenhydramine_C18-PFP_pH9.png

    All Analgesics, Black Trace 245 nm, Green Trace 200nm
    AllAnalgesics_C18-PFP_pH9.png

    Unknown Tablets on C18-PFP, 55% pH=7 0.025M phosphate buffer

    Unknowns were crushed, dissolved in 250 mL water, and filter with 0.45 micropore filters, followed by a 1:10 dilution in methanol.

    Tablet 1, Black Trace 245 nm, Green Trace 195nm
    Tablet1.png

    Tablet 2, Black Trace 245 nm, Green Trace 200nm
    Tablet2.png

    Tablet 3, Black Trace 245 nm, Green Trace 200nm
    Tablet3.png

    Tablet 4, Black Trace 245 nm, Green Trace 200nm
    Tablet4.png

    Tablet 5, Black Trace 245 nm, Green Trace 195nm
    Tablet5.png

    Supplemental Information

    All stock solutions were made by dissolving weight listed of analgesic in 50.0 mL methanol

    Stock Compounds
    (Amount in Stock)

    pKa

    Melting Point

    Structure

    Aspirin (acetylsalicyclic acid)

    90mg

    3.49

    134-6˚C

    Aspirin.png

    Caffeine

    30 mg

    10.4

    238˚C

    Caffeine.png

    Salicyclamide

    90 mg

    8.37

    140-4˚C

    Salicyclamide.png

    Phenacetin

    12 mg

    2.2

    133-8˚C

    Phenacetin.png

    Acetaminophen

    5 mg

    9.38-9.9

    169˚C

    Acetaminophen.png

    Ibuprofen

    50 mg

    4.91-5.2

    76˚C

    Ibuprofen.png

    Diphenhydramine HCl

    50 mg

    9-10.10

    166˚C

    DiphenhydramineHCl.png

    Column Chemistries

    C18 particle surface

    C18.png

    RP-Amide particle surface (polar embedded group)

    RP-Amide.png

    C18-PFP particle surface (polar endcapped)

    C18-PFP.png

    Contributors and Attributions

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