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Separation of DOPA (3,4-dihydroxy-L-phenylalanine) Neurotransmitters  The neurotransmitters dl-DOPA, creatinine, hydroxytryptophan (5-HTP), and serotonin are separated in less than 4 minutes on a short 50 mm Primesep 200 column. The HPLC separation uses a mobile phase of water, acetonitrile (MeCN, ACN) and trifluoroacetic acid (TFA) and UV detection at 250 nm. Ion-pair reagents were not needed for retention of these polar, hydrophilic compounds, instead a combination of ion-exchange and reversed-phase interactions were used. Application Analytes: Serotonin DOPA (3,4-dihydroxy-L-phenylalanine) 5-HTP Creatinine Application Detection: UV Detection Catecholamine Pathway  Primesep 200 separates catecholamines in the catecholamine pathway in 10 minutes. Phenylalanine, tyrosine, DOPA, dopamine, norepinephrine, and epinephrine are baseline resolved by a combination of reversed-phase, ion-exchange, and ion-exclusion mechanisms. Excellent peak shape results with a mass spec compatible mobile phase of water, acetonitrile (MeCN, ACN) and trifluoracetic acid (TFA) with UV detection at 210 nm. Application Analytes: Phenylalanine Tyrosine DOPA (3,4-dihydroxy-L-phenylalanine) Dopamine Epinephrine Application Detection: UV Detection Bufferless Ion Separation (BLIS™) Chromatography of Amino Acids (1)  Application Analytes: Phenylalanine Tyrosine DOPA (3,4-dihydroxy-L-phenylalanine) Application Detection: UV Detection HPLC Separation of Compounds of Catecholamine Pathway  The catecholamine neurotransmitters are amino acid derivatives of tyrosine. DOPA, tyrosine, phenylalanine, norepinephrine, epinephrine, and dopamine and baseline resolved on a Primesep 200 column. The HPLC separation uses a mobile phase of water, acetonitrile (MeCN, ACN), trifluoracetic acid (TFA) or ammonium formate and ultraviolet (UV) detection at 210 nm. Peak order and retention time can be changed by switching from TFA to ammonium formate in the mobile phase. Application Analytes: DOPA (3,4-dihydroxy-L-phenylalanine) Tyrosine Phenylalanine Epinephrine Dopamine Application Detection: UV Detection ELSD/MS Detection HPLC Separation of Polar and Hydrophobic Drugs on Obelisc R and N  Application Analytes: DOPA (3,4-dihydroxy-L-phenylalanine) Dopamine Propyl Paraben Application Detection: UV Detection Separation of Serotonin, Dopamine, and Related Compounds  Catecholamines are chemical compounds derived from the amino acid tyrosine containing catechol and amine groups. Some of them are biogenic amines. Retention of compounds of catecholamine pathway is achieved on Obelisc N column. All polar compounds are well retained by combination of HILIC and ion-exchange mechanisms. Obelisc N columns produce very good peak shapes for all analytes. Method is very sensitive to amount of ACN, buffer and buffer pH. Retention time changes with variation of main parameters. This method can be used for quantitation of biogenic amines and related compounds (homovanillic acid, dihydroxyphenyl acetic acid, serotonin, dopamine, epinephrine, hydroxytryptophan, epinephrine and DOPA) in urine, blood and other biological fluids. Further optimization of this HPLC method can be used during screening and validation. Amines and acids can be analyzed in the same run and retained by combination of polar organic mode, cation-exchange and anion-exchange modes. Various buffers within specified pH can be employed (ammonium formate, ammonium acetate, sodium phosphate, etc.). Application Analytes: Homovanillic Acid DOPAC (Dihydroxyphenylacetic Acid) Serotonin Dopamine Epinephrine Hydroxytryptophan Norepinephrine DOPA (3,4-dihydroxy-L-phenylalanine) Application Detection: UV Detection Separation of Catecholamines on Primesep 100 Column with Phosphate Buffers
The catecholamine neurotransmitters are amino-acid derivatives of tyrosine. DOPA, tyrosine, phenylalanine, norepinephrine, epinephrine, and dopamine and baseline are resolved on a Primesep 100 column with UV-transparent phosphate buffer. This method can be used for analysis of catecholamines and related impurities in various matrices. Peak order and retention time can be changed by changing the amount of ACN, buffer concentration and buffer pH. Various buffers can be used to accommodate desired detection technique. Primesep 100 is a reversed-phase cation-exchange mixed-mode column that can be used for analysis of polar neutral, polar ionizable, polar zwitter-ionic, hydrophobic neutral, and hydrophobic ionic compounds in the same run. Column can be operated in reverse-phase, cation-exchange, anion-exclusion, HILIC and mixed-modes depending on the mobile phase selection and nature of analytes. Column is compatible with LC/MS and does not require use of ion-pairing reagents. Application Analytes: DOPA (3,4-dihydroxy-L-phenylalanine) Dopamine Epinephrine Norepinephrine Phenylalanine Tyrosine Application Detection: UV Detection Separation of Amino Acids in HILIC and Cation-Exchange Modes
Amino acids can be retained and separated on a Primesep S2 column in HILIC/cation-exchange mode. Application Analytes: DOPA (3,4-dihydroxy-L-phenylalanine) Phenylalanine Tyrosine Application Detection: UV Detection |
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