Application of high-field proton nuclear magnetic resonance ( 1 H-NMR) spectroscopy for the analysis of explosives and related compounds in groundwater samples ? a comparison with the high-performance liquid chromatography (HPLC) method

A simple high performance liquid chromatography (HPLC) method of separating and quantitating the predominant organic solutes of the renal medulla is described. These organic solutes include myo-inositol, glycerophosphorylcholine, sorbitol, betaine, and urea. Other physiologically significant solutes, including glucose and mannitol, can be separated and quantitated concurrently with this method. With the use of this technique, the organic solutes of the rabbit kidney were determined. No new organic compounds were detected by HPLC that could significantly contribute to intracellular osmolality of the medulla. The values for the organic solutes already described were similar to those obtained by more complicated and limited approaches such as classical enzymatic techniques, ion electrodes, nuclear magnetic resonance spectroscopy, and gas chromatography-mass spectroscopy.

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Water quality. Determination of certain explosives and related compounds. Method using high-performance liquid chromatography (HPLC) with UV detection

10.3403/30060323 ◽

2006 ◽

Keyword(s):

Water Quality ◽

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

High Performance ◽

Uv Detection ◽

Related Compounds ◽

Explosives And Related Compounds

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Developing a High-performance Liquid Chromatography Method for Simultaneous Determination of Loratadine and its Metabolite Desloratadine in Human Plasma

Current Drug Metabolism ◽

10.2174/1389200220666191125095648 ◽

2020 ◽

Vol 20 (13) ◽

pp. 1053-1059

Author(s):

Mahmoud M. Sebaiy ◽

Noha I. Ziedan

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Human Plasma ◽

High Performance ◽

Allergic Diseases ◽

Reversed Phase ◽

Hplc Method ◽

H1 Receptor ◽

Chromatography Method

Background: Allergic diseases are considered as the major burden on public health with increased prevalence globally. Histamine H1-receptor antagonists are the foremost commonly used drugs in the treatment of allergic disorders. The target drug in this study, loratadine, belongs to this class of drugs and its biometabolite desloratadine which is also a non-sedating H1 receptor antagonist with anti-histaminic activity being 2.5 to 4 times greater than loratadine. This study aimed to develop and validate a novel isocratic Reversed-phase High-Performance Liquid Chromatography (RP-HPLC) method for rapid and simultaneous separation and determination of loratadine and its metabolite, desloratadine in human plasma. Methods: The drug extraction method from plasma was based on protein precipitation technique. The separation was carried out on a Thermo Scientific BDS Hypersil C18 column (5μm, 250 x 4.60 mm) in a mobile phase of MeOH: 0.025M KH2PO4 adjusted to pH 3.50 using orthophosphoric acid (85: 15, v/v) at an ambient temperature. The flow rate was maintained at 1 mL/min and maximum absorption was measured using the PDA detector at 248 nm. Results: The retention times of loratadine and desloratadine in plasma samples were recorded to be 4.10 and 5.08 minutes, respectively, indicating a short analysis time. Limits of detection were found to be 1.80 and 1.97 ng/mL for loratadine and desloratadine, respectively, showing a high degree of sensitivity of the method. The method was then validated according to FDA guidelines for the determination of the two analytes in human plasma. Conclusion: The results obtained indicate that the proposed method is rapid, sensitive in the nanogram range, accurate, selective, robust and reproducible compared to other reported methods.

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