Acetic acid liquid chromatography

HPLC High Performance Liquid Chromatography LHRH Lutenizing Hormone Releasing Hormone PTC Phase transfer catalyst SPPS Solid Phase Peptide Synthesis TFA Trifluoro acetic acid... 

High-performance liquid chromatography (HPLC) with a micellar mobile phase or with a selective pre-column or reaction detection system has also been used to determine alkylenebis(dithiocarbamaes). ° Zineb and mancozeb residues in feed were determined by ion-pair HPLC with ultraviolet (UV) detection at 272 nm. These compounds were converted to water-soluble sodium salts with ethylenediaminetetra-acetic acid (EDTA) and sodium hydroxide. The extracts were ion-pair methylated with tetrabuthylammonium hydrogensulfate (ion-pair reagent) in a chloroform-hexane solvent mixture at pH 6.5-8.S. The use of an electrochemical detector has also been reported. ... 

Figure 8.43 Separation of enantiomers using complexation chromatography. A, Separation of alkyloxiranes on a 42 m x 0.2S mm I.O. open tubular column coated with 0.06 M Mn(II) bis-3-(pentafluoro-propionyl)-IR-camphorate in OV-ioi at 40 C. B, Separation of D,L-amino acids by reversed-phase liquid chromatography using a mobile phase containing 0.005 M L-histidine methyl ester and 0.0025 M copper sulfate in an ammonium acetate buffer at pH 5.5. A stepwise gradient using increasing amounts of acetonitrile was used for this separation.

Horikawa [126] has adapted a thermal detector for the determination of formic, acetic, and propionic acids by liquid chromatography. 

Rebif is produced via recombinant DNA technology in a CHO cell line. It displays an identical amino acid sequence to that of native human IFN-P-la and, like the native product, is glycosylated. After cell culture the interferon is purified using a series of chromatographic steps (affinity, ion-exchange, gel-filtration and reverse-phase liquid chromatography). It is formulated as a sterile solution in pre-filled syringes and contains mannitol, HSA, sodium acetate, acetic acid and sodium hydroxide as excipients. It is administered subcutaneously three times weekly. 

Davies, I.D., Allanson, J.P., and Causon, R.C. 1999. Rapid determination of the anti-cancer drug chlorambucil (Leukeran) and its phenyl acetic acid mustard metabolite in human serum and plasma by automated solid-phase extraction and liquid chromatography-tandem mass spectrometry. J. Chrom-matogr. B. 732 173. 

Fig. 9. Conjoint Liquid Chromatography (CLC). Separation of proteins from mouse ascites and isolation of monoclonal antibody IgG in one step obtained by a combination of CIM QA and CIM Protein A Disks. Conditions Separation mode CLC (first disk CIM QA, 12 x 3 mm ID, 0.34 ml second disk - CIM Protein A, 12 x 3 mm ID, 0.34 ml, inserted in monolithic column housing) Instrumentation Gradient HPLC system with extra low dead volume mixing chamber Sample Mouse ascites Injection volume 20 pL Mobile Phase Buffer A 20 mM Tris-HCl, pH 7.4 Buffer B Buffer A + 1 M NaCl Buffer C 0.1 M Acetic acid Conditions Gradient 0 - 50 % B in 50 s, 100% A for 40 s, 100% C for 30 s Flow Rate 4 ml/min Detection UV at 280 nm... 

Sulphonated azo dyes were separated and quantitated in various food products by ion-pair liquid chromatography with DAD and electrospray MS detection. The chemical structure of sulphonated azo dyes included in the investigation are shown in Fig. 3.36. Dyes were separated in an ODS column (125 X 2.0 mm i.d. particle size 5 pm) using gradient elution. An aqueous solution of 3 mM triethylamine (pH adjusted to 6.2 with acetic acid) and methanol... 

Figure 4.15 Ion-pair liquid chromatography of free amino acids using a column switching system. Column I, butyl-bonded silica gel, 50 x 4.6 mm i.d., 2, octyl-bonded silica gel, 50 x 4.6 mm i.d., and 3, octadecyl-bonded silica gel, 250 x 4.6 mm i.d. eluent, 0.01 m sodium acetate buffer (pH 5.6) containing 4 mM copper acetate and 0.8 mM sodium heptanesulfonate flow rate, 1 ml min-1 detection, UV 235 nm. Peaks 1, Tyr 2, Val 3, Met 4, His 5, Lys 6, lie, 7, Leu 8, Phe 9, Arg 10, Asp 11, Ser 12, Glu 13, Thr 14, Gly 15, Pro 16, Cys and 17, Ala. 1-9 were separated on column 1 and 10-17 were separated by a combination of columns 2 and 3.

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