Liquid-chromatographic measurement of biopterin and neopterin in serum and urine

1990 ◽  
Vol 36 (7) ◽  
pp. 1364-1368 ◽  
Author(s):  
W E Slazyk ◽  
F W Spierto

Abstract We report an improved "high-performance" liquid-chromatographic (HPLC) method for measuring biopterin and neopterin in serum and urine. Specimens are acidified, treated with iodine in 0.2 mol/L trichloroacetic acid, party purified on Bio-Rad MP-50 cation-exchange columns, and analyzed by reversed-phase HPLC with fluorometric detection. The minimal concentration of biopterin detectable is 0.3 micrograms/L in a 50-microL injection. The total CV is less than or equal to 10%. Improvements over other reported methods include the use of a single, simplified sample-preparation step with a Baker-10 SPE System, and a guard column to increase analytical column stability and analyte recovery. The assay is semiautomated to reduce technician time and improve precision. Mean observed values for biopterin and neopterin in sera of normal human adults were 1.64 and 5.52 micrograms/L, respectively. The mean ratio of neopterin to biopterin in acidified adult urine samples was lower than that found in matched nonacidified samples (n = 10). Serum specimens from diagnosed phenylketonuric (PKU) and hyperphenylalaninemic patients were also analyzed for biopterin and neopterin; the findings agreed with reported values for similar patients. One patient, previously identified as an atypical PKU patient, showed serum values of neopterin and biopterin suggestive of a defect in biopterin synthesis.

1990 ◽  
Vol 36 (1) ◽  
pp. 5-8 ◽  
Author(s):  
J G Goddard ◽  
G J Kontoghiorghes

Abstract "High-performance" liquid-chromatographic (HPLC) methods have been developed for identifying 1-substituted 2-alkyl-3-hydroxypyrid-4-one iron chelators in serum and urine. Ion pairing with heptane- or octanesulfonic acid in pH 2.0-2.2 phosphate buffer and reversed-phase chromatography were required to separate these compounds from endogenous compounds in both biological fluids. In both the 2-methyl and 2-ethyl series of 1-substituted compounds (H, methyl, ethyl, or propyl) the elution times increased in accordance with the n-octanol/water partition coefficients (propyl greater than ethyl greater than H greater than methyl). Urine samples were filtered (0.4 microns pore size) and injected either undiluted or after dilution with elution buffer. After the addition of internal standard, the plasma or serum samples were deproteinized by treatment with HCIO4, 0.5 mol/L, centrifuged, and the supernates were injected directly onto the HPLC. Using these procedures, we could identify 1,2-dimethyl-3-hydroxypyrid-4-one (L1) in the serum and urine of a thalassemic patient who had received a 3-g dose of the drug and in the urine of other patients who had received the same dose. One or more possible metabolites were also observed in the chromatograms of both urine and serum. The 24-h urinary output of L1 (0.22-2.37 g) and iron (10.6-71.5 mg) varied but there was no correlation between the two with respect to quantity or concentration. Instead, urinary iron output was higher in patients with a greater number of transfused units of erythrocytes. This is the first study in humans to show that L1 is absorbed from the gut, enters the circulation, and is excreted in the urine.


INDIAN DRUGS ◽  
2013 ◽  
Vol 50 (05) ◽  
pp. 48-52
Author(s):  
A Lodhi ◽  
◽  
A Jain ◽  
B. Biswal

A validated high performance liquid chromatographic method was developed for the determination of chromium picolinate in pharmaceutical dosage forms. The analysis was performed at room temperature using a reversed-phase ODS, 5µm (250×4.6) mm column. The mobile phase consisted of acetonitrile: buffer (60:40 V/V) at a flow rate of 0.5 mL/min. The PDA-detector was set at 264 nm. The developed method showed a good linear relationship in the concentration range from 1.5 – 12.5 µg/mL with a correlation coefficient from 0.999. The limit of detection and limit of quantification were 0.0540513 and 0.1637919 µg/mL respectively.


2013 ◽  
Vol 2013 ◽  
pp. 1-4
Author(s):  
Suying Ma ◽  
Haixia Lv ◽  
Xiaojun Shang

A high performance liquid chromatographic (HPLC) method with UV detector for the determination of dyclonine hydrochloride and a gas chromatography (GC) method with flame ionization detector (FID) for the determination of camphor and menthol in lotion were developed. The developed HPLC method involved using a SinoChoom ODS-BP C18reversed-phase column (5 μm, 4.6 mm × 200 mm) and mobile phase consisting of acetonitrile : water : triethylamine in a ratio of 45 : 55 : 1.0; pH was adjusted to 3.5 with glacial acetic acid. The developed GC method for determination of camphor and menthol involved using an Agilent 19091J-413 capillary chromatographic column (30 m × 320 μm × 0.25 μm). The two methods were validated according to official compendia guidelines. The calibration of dyclonine hydrochloride for HPLC method was linear over the range of 20–200 μg/mL. The retention time was found at 6.0 min for dyclonine hydrochloride. The calibration of camphor and menthol of GC method was linear over the range of 10–2000 μg/mL. The retention time was found at 2.9 min for camphor and 3.05 min for menthol. The proposed HPLC and GC methods were proved to be suitable for the determination of dyclonine hydrochloride, camphor, and menthol in lotion.


INDIAN DRUGS ◽  
2019 ◽  
Vol 56 (07) ◽  
pp. 43-49
Author(s):  
B.P. Manjula ◽  
V. G Joshi ◽  
Siddamsetty Ramachandra Setty ◽  
M Geetha ◽  

Tea tree oil, an active ingredient of skin, hair and nail care cosmeceuticals, has claims for topical antimicrobial, analgesic and anti-inflammatory activity. Its complex composition is governed by ISO 4730:2017. Terpinene-4-ol is the principal constituent of the oil (35% - 48%) followed by γ-terpinene (14% -28%), α-terpinene (6%-12%) and 1,8-cineole (≤15%). A reversed-phase, isocratic high performance liquid chromatographic method has been developed and validated for routine determination of tea tree oil based on1,8-cineole content in bulk and commercially available cosmeceuticals using C18 column, methanol-water (70:30 v/v) as mobile phase and flow rate of 1mL/min. UV detection was done at 200 nm. Linearity of the method was established for 20-100μL/mL (R2 = 0.9992) with LOD, LOQ values of 0.5594 μL/mL and 5.5941μL/mL respectively. The % RSD values for robustness and precision were <1% and recovery ranged between 99.09-102.96%. The method was successfully applied for determination of 1,8-cineole content in cosmeceuticals.


2008 ◽  
Vol 91 (4) ◽  
pp. 739-743 ◽  
Author(s):  
Andréia de Haro Moreno ◽  
Hérida Regina Nunes Salgado

Abstract A rapid, accurate, and sensitive high-performance liquid chromatographic (HPLC) method was developed and validated for the determination of ceftazidime in pharmaceuticals. The method validation parameters yielded good results and included range, linearity, precision, accuracy, specificity, and recovery. The excipients in the commercial powder for injection did not interfere with the assay. Reversed-phase chromatography was used for the HPLC separation on a Waters C18 (WAT 054275; Milford, MA) column with methanolwater (70 + 30, v/v) as the mobile phase pumped isocratically at a flow rate of 1.0 mL/min. The effluent was monitored at 245 nm. The calibration graph for ceftazidime was linear from 50.0 to 300.0 g/mL. The values for interday and intraday precision (relative standard deviation) were &lt;1. The results obtained by the HPLC method were calculated statistically by analysis of variance. We concluded that the HPLC method is satisfactory for the determination of ceftazidime in the raw material and pharmaceuticals.


2008 ◽  
Vol 91 (5) ◽  
pp. 1070-1074 ◽  
Author(s):  
Arun M Prajapati ◽  
Satish A Patel ◽  
Natvarlal J Patel ◽  
Dipti B Patel ◽  
Sejal K Patel

Abstract This research paper describes validated reversed-phase high-performance column liquid chromatographic (RP-HPLC) and first-derivative UV spectrophotometric methods for the estimation of voriconazole (VOR) in oral suspension powder. The RP-HPLC separation was achieved on Phenomenex C18 column (250 4.6 mm id, 5 m particle size) using wateracetonitrile (40 + 60, v/v; pH adjusted to 4.5 0.02 with acetic acid) as the mobile phase at a flow rate of 1.4 mL/min and ambient temperature. Quantification was achieved with photodiode array detection at 255 nm over the concentration range of 0.11 g/mL with mean recovery of 99.49 0.83 for VOR by the RP-HPLC method. Quantification was achieved with UV detection at 266 nm over the concentration range of 820 g/mL with mean recovery of 99.74 0.664 for VOR by the first-derivative UV spectrophotometric method. These methods are simple, precise, and sensitive, and they are applicable for the determination of VOR in oral suspension powder.


2007 ◽  
Vol 90 (6) ◽  
pp. 1526-1531 ◽  
Author(s):  
Bharathi Avula ◽  
Yan-Hong Wang ◽  
Rahul S Pawar ◽  
Yatin J Shukla ◽  
Ikhlas A Khan

Abstract Hoodia gordonii, family Asclepiadaceae, is a succulent plant and is traditionally used in southern Africa for its appetite-suppressant properties. A high-performance liquid chromatographic (HPLC) method with UV detection for analysis of 11 oxypregnane glycosides from H. gordonii has been developed. The simultaneous analysis of 11 oxypregnane glycosides was achieved with a Phenomenex (Torrance, CA) reversed-phase C18 column using gradient mobile phase of water and acetonitrile, both containing 0.025 trifluoroacetic acid. The developed method was applied to the identification of oxypregnane glycosides in 3 different species of Hoodia and 23 related genera. The HPLC profiles of various plant samples were compared for the presence of oxypregnane glycosides.


2017 ◽  
Vol 15 (2) ◽  
pp. 187-194 ◽  
Author(s):  
Md Shahadat Hossain ◽  
Md Samiul Islam ◽  
Subrata Bhadra ◽  
Abu Shara Shamsur Rouf

Highly nutritious dairy products are ingested regularly by all ages of population. Adulteration of dairy products to enhance the inherent stability and acceptability to common consumers by different harmful and toxic ingredients like formalin, an unpermitted preservative, has been a burning issue in Bangladesh over the last few years. The aim of this paper was to analyze the concentration of formaldehyde in dairy products most commonly sold in Bangladeshi markets by a validated reversed phase high performance liquid chromatographic (RP-HPLC) method to reveal the on-going alarming scenario in a scientific way. After pre-derivatization with 2,4- dinitrophenylhydrazine, formaldehyde was detected at 345 nm using a C18 column with acetonitrile and water (45:55) as mobile phase at a flow rate of 2.0ml/min. The validated method has been applied to 41 marketed dairy products, including pasteurized milk, UHT milk, banana- mango- and chocolate-milk, flavored yoghurt, lassi, buttermilk, and skimmed milk. However, no formaldehyde was detected among the tested dairy products.Dhaka Univ. J. Pharm. Sci. 15(2): 187-194, 2016 (December)


2009 ◽  
Vol 92 (4) ◽  
pp. 1035-1043 ◽  
Author(s):  
Morteza Mehrdad ◽  
Mahnoosh Zebardast ◽  
Ghazaleh Abedi ◽  
Mitra Nouri Koupaei ◽  
Hoda Rasouli ◽  
...  

Abstract A rapid and simple reversed-phase high-performance liquid chromatographic method using a monolithic column was developed and validated for the separation and quantification of myricetin, quercetin, and kaempferol in Rhus coriaria L. The method employed the isocratic mobile phase acetonitrile10 mM potassium dihydrogen orthophosphate buffer adjusted to pH 3.0 using orthophosphoric acid (38 + 62, v/v) at a flow rate of 4.0 mL/min; a Chromolith Performance RP-18e (100 4.6 mm) monolithic column kept at 40C; and UV detection at 370 nm. Although the elution order was identical and the selectivity was equivalent, the comparison between monolithic and particulate columns showed that the monolithic column could reduce the separation time to &lt;1 min without sacrificing column efficiency and selectivity. The method was validated according to International Conference on Harmonization guidelines. The validation characteristics included accuracy, precision, linearity, range, specificity, LOQ, and robustness. The calibration curves were linear (r &gt;0.999) over the concentration range of 0.8888.3 g/mL for myricetin, 0.9595 g/mL for quercetin, and 1.43143.3 g/mL for kaempferol. The recoveries for all three compounds were above 89. Myricetin was found to be the major flavonol in the examined plant extracts, followed by minor quantities of quercetin and kaempferol.


2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Hong Yan ◽  
Pei Xu ◽  
Hai Huang ◽  
Juan Qiu

AbstractA pre-column derivatized high-performance liquid chromatographic (HPLC) method with ultraviolet-visible detection was developed to measure the concentrations of spectinomycin in fermentation broth. Derivatization reagents, 2,4-dinitrophenylhydrazine in acetonitrile (5 mg mL−1) and trifluoroacetic acid in acetonitrile (0.8 mol L−1), were added to an aliquot of the fermentation broth, and the mixture was incubated for 60 min at 70°C. The resulting derivative was separated from other compounds by isocratic elution in a reversed-phase column Zorbax SB-C18 (250 mm × 4.6 mm, 5 µm). Mobile phase consisted of acetonitrile, tetrahydrofuran, and water (φ r = 40: 35: 25) and the flow rate was 1.0 mL min−1. The detection wavelength was 415 nm. The standard curve for spectinomycin sulfate was linear with correlation coefficients of 0.9997 in the range of 25 µg mL−1 to 600 µg mL−1. The relative standard deviation values ranged from 0.43 % to 2.18 % depending on the concentration of samples. The average recovery was 101.5 %. The limit of detection was 50 ng mL−1.


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