Trans-3-Hydroxycinnamic Acid in Human Urine with LCMS – AppNote

Separation of Antioxidants with HPLC with LCMS Polar metabolites are reproducibly retained using an MS friendly Mobile Phase in Aqueous Normal Phase (ANP) HPLC. The sample preparation required is very easy and cost effective compared to previous, older Methods. The sample is diluted with the Reversed Phase Solvents and ready to inject in 5-10 minutes. […]

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Transfer HPLC Method to UHPLC with Hydrophobic Compounds – AppNote

Separation of Hydrophobic Compounds with HPLC & UHPLC This AppNote shows separation of analytes within a range of hydrophobicity. A simple gradient is used to elute all the compounds and baseline separation is obtained for the critical pair (peaks 4 and 5) and the least hydrophobic compound is adequately retained. A comparison is shown in […]

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Triamterene Analyzed with HPLC – AppNote

Symmetrical Peak Shape without Ion Pair Agents Triamterene has numerous amine functional groups and therefore tails readily in Reversed Phase Methods if ion pair agents are not used in the Mobile Phase. However, these additives not only contribute to a less Robust Method in terms of Reproducibility of analyte Retention, but are also incompatible with […]

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Trimethobenzamide Analyzed with HPLC – AppNote

Separation of Trimethobenzamide with a Simple Isocratic Method  The USP Assay Method of Trimethobenzamide is performed by titration. This alternative HPLC approach is fast, easy, and reliable. It has many advantages over the titration Method, including ease of automation and less operator-dependent results. This simple isocratic Method provides sufficient Retention of the API to allow […]

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Triton X-100 Assay with HPLC- AppNote

A Sensitive Assay for Detection of a Non-ionic Surfactant  Triton X-100 is used in the sample purification steps of various materials as well as for cleaning apparatus in pharmaceutical manufacturing.  Due to the toxic nature of Triton X-100, a sensitive method for its detection and quantification is very important to identify any residual amounts. This simple […]

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Tropicamide and Homatropine Analyzed with HPLC – AppNote

Separation of Anticholinergic Mydriatic Agents In this Method, Tropicamide and Homatropine are separated with a simple Gradient. Homatropine is significantly hydrophobic yet still retains well. Furthermore, the Separation between these two solutes is good, illustrating the Selectivity capabilities of this Method. Data is shown for two lots of Columns in order to demonstrate the robustness […]

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Tryptamine Analyzed with HPLC – AppNote

Simple and Fast Analyses of an Important Biogenic Amine Using this Method to analyze Tryptamine produces excellent Peak Shape and Reproducible Retention Times as shown. It is very polar and very difficult to Retain when using standard C18 Columns. The baseline in this Chromatogram appears to be noisy but it is due the low UV […]

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Tyramine, N-Methyltyramine & Synephrine Analyzed with LCMS – AppNote

Adrenergic Amines found in Citrus Fruit Juice with LCMS This Method, developed for the analysis of Tangerine Juice is Sensitive, Fast, Simple and Reproducible when using a Mass Spectrometer. The resulting Sample and diluent, after centrifugation, is fully compatible with the Mobile Phase (listed below), which allows direct injection with no further Sample Prep being […]

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UDP-Glucose Analyzed with LCMS – AppNote

Analyzing a Nucleotide Sugar with UDP-Hexanolamine as an Internal Standard This Method is rapid and simple and it can also be used in measuring UDP Glucose. The advantages of using this Method to assay Nucleotide Sugars such as this one are the short Separation Time, long term Column Stability and rapid Equilibration time between a […]

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Unique Method Development Strategy for Polar Compounds – AppNote

Anatoxin-a Analyzed with LCMS Figures below illustrate an example of the work flow in developing a Method for the Analysis of a Polar Compound using Cogent Diamond Hydride™ Columns and the impact of Aqueous Normal Phase HPLC. The simplified steps of Method Development are as follows: —A. Injection of the Sample at 50:50 Solvent A […]

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Urea Analyzed with HPLC – AppNote

Retention of Urea, a Highly Polar Compound Urea is very difficult to retain by conventional HPLC methods. It is highly polar and therefore shows little or no Reversed Phase retention. However, this Method shows how it can be readily retained past the solvent front using a simple isocratic Mobile Phase. Furthermore, the Peak shape for […]

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Urea Analyzed with HPLC- AppNote

Fast, Reproducible Method In this Method Urea was retained when a 100% DI Water Mobile Phase was used. DI Water can be used as the complete Mobile Phase without fear of phase “de-wetting” and subsequent loss of retention time. This Method has the advantage of being very simple, without time consuming derivatization or reaction steps […]

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Uric Acid (UA) Metabolites Analyzed by LCMS – AppNote

Allantoin and 6-Aminouracil The presented method for analysis of UA metabolites in human Urine is very simple and does not require Mobile Phase additives or pre-Column derivatization. The peaks are symmetrical and the MS signal is not diminished as is the case when Ammonium Formate or Acetate is used as the Mobile Phase additive. The […]

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Uric acid and Metabolites Analyzed by LCMS – AppNote

LCMS Method for Allantoin, 6-Aminouracil, and Uric Acid (UA) The presented method for analysis of UA and its highly polar metabolites is simple and does not require Mobile Phase additives or pre-column derivatization. The Peaks are symmetrical, and the MS signal is not diminished, as is the case when Ammonium Formate or Acetate is used […]

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Valaciclovir & Degradants Analyzed with LCMS – AppNote

Separation of Valaciclovir from two Degradants The anti-viral Herpes drug Valaciclovir and its degradation products are analyzed using Aqueous Normal Phase HPLC with MS detection. The Method development was completed using UV detection, where excellent Separation between the Prodrug Valaciclovir and its active converted degradant, Acyclovir, was observed. The Method transfer from UV to MS […]

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Valaciclovir Analyzed with HPLC – AppNote

Separation of Prodrug from a Degradant in Forced Degradation of Valtrex® Tablets In this Application Note, the anti-viral Herpes drug Valaciclovir and its main acid degradant are well separated (Figure A). Valaciclovir is a prodrug and the degradant observed here is believed to be the active form, Acyclovir. Both compounds did not retain very strongly […]

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Valsartan and Hydrochlorothiazide Analyzed with HPLC – AppNote

Improved Gradient Method with Faster Equilibration The USP Assay Method for Valsartan in combination with Hydrochlorothiazide features a 27 minute gradient with a 13 minute re-equilibration for a total run time of 40 minutes. In this method, the run time was a quarter of the USP method, and the Column equilibrates much faster when gradients […]

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Vancomycin Analyzed with HPLC- AppNote

Retention of a Highly Polar Antibiotic As a highly polar compound, Vancomycin is difficult to retain with Reversed Phase Methods. In this Method the compound retains very well as illustrated in the Figure. In addition, the repeatability of the analysis, which is demonstrated by the overlay of five consecutive runs, is excellent. The Mobile Phase […]

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Vancomycin HPLC Method Transferred – AppNote

Benefits of using 2.2 µm Column for Vancomycin Analysis The highly polar antibiotic Vancomycin can be readily analyzed with either the standard 4µm Cogent Diamond Hydride or the Cogent Diamond Hydride 2.o Column. Notably higher efficiency is obtained on the smaller particle size Column. This Method is easy to perform and is LCMS compatible. Three […]

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Vanillic Acid and 6′-O-Feruloylsucrose Analyzed with LCMS – AppNote

Rice Extract Sample Containing Vanillic Acid and Feruloylsucrose Click HERE for Column Ordering Information. When commercial Rice Extracts were analyzed, only Vanillic Acid (Peak 1) was found in one out of 3 Extracts and 6′-O-Feruloylsucrose (peak 2) was found in all 3 extracts. The results were confirmed by analyzing spiked Rice Extract samples. The analysis […]

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Vardenafil (Levitra®) Analyzed with HPLC – AppNote

LC-MS Compatible Assay Method Vardenafil in a tablet formulation can be readily assayed with this LC-MS compatible gradient method. The peak tailing factor was close to unity. The compound has several amine groups which can produce tailing with ordinary HPLC Columns that have a number of surface Silanols. The MS-compatible Mobile Phase means that the […]

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Verapamil and Impurity Analyzed with HPLC – AppNote

Alternative to USP Method with Improved Peak Efficiency  The USP impurities Method for Verapamil uses an Acetate Buffer with the ion pair agent 2-Aminoheptane to reduce Peak Tailing of the API and its Impurity. This Application Note uses an LCMS compatible Mobile Phase and produces Symmetrical Peaks for both Compounds. Excellent Resolution was also obtained […]

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Vitamin K Isomers Analyzed with HPLC – AppNote

Phytonadione Separation by Shape Selectivity In this Method, we separate the two E and Z isomers of Phytonadione on the basis of shape selectivity. The below chromatogram is a five injection overlay with a resolution value of 1.5.  Peaks: 1. Impurity 2. Phytonadione (E isomer) 3. Phytonadione (Z isomer) Method Conditions Column: Cogent UDC-Cholesterol™, 4μm, […]

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Warfarin in a Tablet Analyzed with HPLC – AppNote

Excellent Peak Shape with an Easy to Run Method This Method is easy to prepare, use and reproduce. Note the Excellent Peak Shape for this Compound. This Methodology will give a long Column life and many Reproducible Runs. Peak: Warfarin Method Conditions Column: Cogent Bidentate C18™, 4μm, 100Å Catalog No.: 40018-75P Dimensions: 4.6 x 75mm […]

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Warfarin, Hydroxybupropion, and Codeine by LCMS – AppNote

Analysis in Spiked Blood Samples In this application, three pharmaceuticals/metabolites are separated using the Cogent Diol 2.o Column. The blood sample illustrates the suitability of the Column for analysis of more complex matrices. Use of Acetone in the Mobile Phase was found to be appropriate for this LC-MS method. As a less expensive and less […]

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Water Soluble Vitamin Tablet Analysis with HPLC – AppNote

Separation of Water Soluble Vitamins without Ion Pair Agents This AppNote illustrates the Separation of four Hydrophilic, B Vitamins which were extracted from a commercially available tablet formulation. The data shows that these Water soluble B-Vitamins are well Separated from each other and from any Matrix Peaks. The main advantage of this Method over traditional […]

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Xanthine, Uric Acid & Hypoxanthine Analyzed with LCMS – AppNote

Separation of Biomarkers found in Human Fluids A simple Method was developed for the determination of Xanthine (X), Uric Acid (UA), and Hypoxanthine (HX) at concentrations in human urine (can be used for human serum) to support pharmacodynamic (PD) studies of a novel Xanthine Oxidase inhibitor during its clinical development. PD Biomarkers (UA, X, and […]

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Zinc-EDTA Complex – AppNote

No Ion Pair Agents Needed Using conventional analytical methods, retention of metal–EDTA complexes is accomplished using Ion Pair Reversed Phase Chromatography. However, the Ion Pair Agents used in the Mobile Phase are not compatible with Mass Spectrometry. In this AppNote, only Formic Acid is needed in the Mobile Phase in order to obtain retention of […]

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β-Carotene Capsule Analyzed with HPLC – AppNote

Separation from Matrix Peaks Click HERE for Column Ordering Information. Beta-carotene may be taken as a dietary supplement in capsule form. In this case, a wide variety of Matrix Peaks were observed in the chromatographic data. It is possible that some of these peaks are various isomers of all-trans ß-carotene or other similar carotenes. In […]

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