Procena efikasnosti različitih načina pripreme uzoraka za kvantifikaciju organskih komponenata u barutima i dvobaznim raketnim gorivima za analizu HPLC metodom

Objective To make comparative analysis of the glycated hemoglobin A1c(HbA1c) values obtained by three HbA1c test methods in patients with variant hemoglobins. Methods Total of 50 blood samples of patients with different types of variant hemoglobin were collected from January 2012 to December 2012; 25 of them (14 males and 11 females) carried hemoglobin D, Q, G, J and E with a mean age of (24±3) years; the other 25 cases (11 males and 14 females) were blood samples with hemoglobin F from newborn infants. Meanwhile, 50 blood samples(25 males and 25 females) from people without variant hemoglobins were also collected as control(mean age (25±5) years). Three methods were used to test HbA1c, which were affinity high performance liquid chromatography (HPLC) method (Ultra 2 of American Primus), ion exchange HPLC method (VariantⅡ of American Bio-Rad and G8 of Japanese Tosoh) and immunization method (DCA Vantage of German Siemens). The statistic analysis were done with variance analysis and correlation analysis. Results The HbA1c of the group with normal HbA1c structure was 5.7%±1.1%, 5.7%±1.2%, 5.7%±1.2% and 5.7%±1.1% respectively when it was tested by affinity HPLC method (Ultra2), ion exchange HPLC method (G8), ion exchange HPLC (Variant Ⅱ) and immunization method (DCA Vantage), and there was no significant difference among the groups (F=0.023, P>0.05). In the 25 samples with hemoglobin F, HbA1c could not be detected by ion exchange HPLC or immunoassay method. The fasting blood glucose level correlated with HbA1c level tested by Ultra 2 method (r=0.647, P<0.05), but it didn't correlate with HbA1c level when tested with VariantⅡ and G8 as well as DCA Vantage method. The HbA1c result of affinity HPLC method was free from the disturbance of Hb D, Q, G, J and E, and had a obvious correlation with blood glucose (r=0.823, P<0.05). The HbA1c result of ion exchange HPLC method was disturbed by hemoglobin D, Q, G, J and E in varying degrees. The HbA1c measured by immunization method was associated with blood glucose (r=0.611, P<0.05). Conclusion The HbA1c value obtained by affinity HPLC method can accurately reflect the mean blood glucose level. Variant hemoglobins disturb the HbA1c result tested by ion exchange HPLC method, and the immunization test result is only disturbed by hemoglobin F. Key words: Glycated hemoglobin A1c; Variant hemoglobins; High performance liquid chromatography

Background: The 99mTc-tetrofosmin is a radiopharmaceutical used in oncology for scintigraphic quantification of the myocardial perfusion. The preparation of this drug is based on a complexation reaction of technetium 99 metastable (99mTc) with tetrofosmin. The reference method for quality control is thin layer chromatography, using TLC SA bands. This method is simple but only separates two types of impurities: free technetium and hydrolyzed technetium associated to hydrophilic impurities like gluconate-99mTc and takes from 30 to 35 minutes. This gluconate impurity gives a poor image quality and difficult interpretation issues. HPLC is a sensitive and specific method, it thus, has an interest in controlling RCP and identifying all impurities. Methods: The reference method is a method by planar chromatography TLC SA tape, size 1 cm x 20 cm. Two marks were scored: 3 cm from the edge to indicate the deposit (10 µL of the preparation) and 15 cm by the end of migration. Mobile phase was acetone: dichloromethane (65:35, v/v). The radioactive bands were quantified by counting the radioactivity using a radiochromatograph miniGITA® (Raytest) equipped with a scintillation probe. The chromatographic system consisted in a Symmetry Shield® column RP18 5μm 100Å (Waters) with a gamma detector Gammaram® (Lablogic). Empower® software (Waters) was used for peak integration. The mobile phase, at a rate flow of 1.0 mL / min, consisted of a mixture of acetonitrile (Waters) and titrisol® buffer (Waters) (40:60, v/v). The sample volumes injected were no more than 10 to 30 µL in order not to exceed 50,000 counts per second due to the risk of radioactive detector saturation. Results: The RCP was measured simultaneously by HPLC and reference method in 30 preparations. For HPLC, mean RCP = 97.21%, α= 2.178% [91.6%-99.63%]. For TLC SA, mean RCP = 97.99%, α= 1.135% [94.31%-99.86%]. The results obtained by both methods were compared using the Wilcoxon t test. The RCP obtained either by TLC SA or HPLC methods are not significantly different (p-value = 0,497, higher than in significance ≤ = 0.05) Conclusions: A new HPLC method was developed for the control of the RCP 99mTc-Tetrofosmin. This method is reliable, rapid, sensitive and easy to use when the equipment is available. It allows us to improve the detection of cardiotoxic side effects due to chemotherapy more quickly than TLC SA method and to prevent toxicity by dose adjustment of anticancer drugs. Although the HPLC method does not differ from TLC (reference method), HPLC provides additional information about the quality of the preparation (percentage of gluconate-99mTc). Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2451. doi:1538-7445.AM2012-2451

In this research caffeine content in coffee sample from Abe Dongoro, Sasiga, Gida Ayana and Sibu Sire of Wollega administrative zone of Ethiopia were determined using High Performance Liquid Chromatography (HPLC) and UV-Vis Spectrophotometry methods. Caffeine in aqueous extract of coffee samples was extracted with dichloromethane prior to analysis by UV-Vis spectrophotometry method and dichloromethane was evaporated from the extract and the extract was dissolved in water (HPLC grade) to determine caffeine contents in coffee samples using HPLC method. The linearity of the HPLC and UV-Vis spectrophotometry methods were R² = 0.9999 and R² = 0.9997 respectively. HPLC and UV-Vis spectrophotometry methods were found to be accurate with recoveries of 97.5% and 117.4%, respectively. Limits of detection (LOD) obtained were 0.148 mg/L for HPLC method and 0.284 mg/L for UV-Vis spectrophotometric method. The caffeine contents in coffee samples obtained using UV-Vis spectrophotometry method was 3.42, 2.638, 2.207 and 2.986 mg/L for Abe Dongoro, Gida Ayana, Sasiga and Sibu Sire coffee samples respectively. Similarly, using HPLC method the caffeine contents in coffee samples obtained was 1.871, 1.601, 1.307, 1.83 mg/L for Abe Dongoro, Gida Ayana, Sasiga and Sibu Sire coffee samples. There is a significant difference between the caffeine contents in coffee samples obtained by the two methods.

Comparison of three methods for detection of melamine in compost and soil

Purpose: To develop a rapid and simple siphonodin content-based high performance liquid chromatography (HPLC) method to distinguish Hemsleya omeiensis from other sources of xuedan.&#x0D; Methods: Siphonodin was isolated from Hemsleya omeiensis and identified by x-ray crystallographic analysis. An optimized HPLC method was applied for the determination of siphonodin contents of H. omeiensis, H. dolichocarpa and H. gigantha.&#x0D; Results: Siphonodin was successfully separated by the optimized HPLC method in &lt; 10 min, and the results of validation showed that the HPLC method was stable and very accurate for the quantification of siphonodin. The mean content of siphonodin in 10 batches of H. omeiensis was 3.78 mg/g, but the compound was not detectable in H. dolichocarpa and H. gigantha using the developed HPLC method.&#x0D; Conclusion: These results indicate that the developed HPLC method is suitable for distinguishing H. omeiensis from other sources of xuedan.

BackgroundRecently, the Nanopia® TDM Zonisamide reagent using the latex particle‐enhanced turbidimetric immunoassay (LTIA) method was developed. The aim of this study was to compare the differences in serum zonisamide (ZNS) concentrations quantified by the high‐performance liquid chromatography (HPLC) method and the LTIA method using a TBA‐25FR analyzer.MethodsA total of 78 samples from 33 patients were quantified by both HPLC and LTIA methods. Deproteinization was used as pretreatment for the HPLC method. The ZNS concentrations quantified by two methods were compared.ResultsThe HPLC method had intra‐ and inter‐day precision lower than 1.86% and 9.00%, and accuracy better than 2.44% and 6.33%, respectively. The LTIA method showed intra‐ and inter‐day precision lower than 2.50% and 5.20%, and accuracy better than 15.80% and 10.60%, respectively. The lower limits of quantification for the HPLC and LTIA methods were 1.0 and 5.0 µg/mL, respectively. The ZNS concentration quantified by the HPLC method correlated strongly with that by the LTIA method (r = 0.953, P < 0.001). A Bland‐Altman plot suggested no systematic error between ZNS concentrations quantified by HPLC and LTIA methods.ConclusionThis study confirmed no differences between the concentrations quantified by the HPLC and LTIA methods at both high and low concentrations, demonstrating the confidence of measurement by the LTIA method.

Aim: Hemoglobin A1c is a valuable parameter for the diagnosis and follow-up of its diabetes mellitus since its biological variation is low, does not require preparation before the test, is not affected by acute stress, and has high preanalytical stability. HbA1c measurement by HPLC has been determined as the reference method by National Glycohemoglobin Standardization Program (NGSP) in USA; after that The International Federation of Clinical Chemistry (IFCC) defined another reference method which could be related with NGSP. In our study, we aim to compare the two NGSP-certified methods of HbA1c, which are high-performance liquid chromatography (HPLC) and turbidimetric inhibition immunoassay (TINIA). Material and Method: HbA1c levels of the patients were measured using two HPLC and one TINIA method in three different hospitals (Lab A, Lab B (Both are HPLC), and Lab C (TINIA), in which Lab A was served as a reference). Because of the lower precision values of LabB, we firstly conducted a method comparison study of 40 volunteers (Group 1). After that, corrective and preventive activities carried out and the precision values in LabB reached the desired range. Following this, another method comparison study consisting of 60 new volunteers (Group 2) was conducted. The statistical flow of this study complied with Clinical Laboratory Standards Institute (CLSI) EP09-A3; Precision studies, Blant-Altman and Passing Bablok regression analysis were performed. Results: The percentage of the mean difference between the two HPLC methods (LabA and LabB) was 3.1%. After corrective and preventive actions had been taken, the mean difference between the two HPLC methods decreased to 2.0%. A decrease in systematic bias was found in our study. Two HPLC methods can be used interchangeably in both Group 1 and Group 2. In Group 1; 95% CI of intercept and slope were found as (-1.41 to -0.30) and (1.03 to 1.22), respectively. In Group 2; 95% CI of intercept and slope were found as (-1.33 to -0.31) and (1.01 to 1.17), respectively. HPLC and TINIA methods could not be used interchangeable without affecting patient results and outcome in both Group 1 and Group 2. Conclusion: Our study concluded that TINIA and HPLC methods could not be used interchangeably without affecting patient results and outcome. Because of the methodology that clinical laboratories are used to, clinicians and clinical biochemists should collaborate on managing diabetes mellitus regarding diagnosis, treatment, and follow-up.

Objectives In this study, we aimed to compare modified Krauss polyacrylamide gradient gel electrophoresis (PAGGE) and high-performance liquid chromatography (HPLC) methods in classification, quantification, and separation of lipoproteins and determining low-density lipoprotein (LDL) size. Methods Blood specimens were obtained from eighty-seven volunteers. We measured LDL size using the PAGGE method and HPLC method with total cholesterol (TC) and triglyceride (TG) peaks. In the PAGGE method, Coomassie Brilliant Blue (CBB) staining was used instead of Sudan black staining, unlike the original method. The relationship between PAGGE and HPLC methods was evaluated by Pearson correlation test and Passing-Bablok regression analysis. Agreement between them was evaluated by Kappa analysis and Bland-Altman plots. Results Statistically significant correlation was found between the LDL size with PAGGE and HPLC methods under the cholesterol curve (HPLC-TC) (r=0.924, p&lt;0.001). Similarly, there was a statistically significant correlation between PAGGE and HPLC methods under the TG curve (HPLC-TG) (r=0.910, p&lt;0.001). In the PAGGE method, within-day precision was found as 2% and between-day precision as 3%. It was determined agreement between HPLC-TC vs. HPLC-TG methods and HPLC-TG vs. PAGGE methods was higher than HPLC-TC vs. PAGGE (Kappa values; 0.68, 0.71, and 0.44, respectively). Conclusions The PAGGE method can be a reliable method for measuring LDL size. HPLC method under cholesterol and triglyceride peaks may be used in clinical practice interchangeably, but clinical decision limits should be different. In addition, our study demonstrated that measurement methods for LDL size could be simplified with several modifications.

Vitamin concentrates with vitamins A and D are used for fortification of fluid milk. Although many of the degradation components of vitamins A and D have an important role in flavor/fragrance applications, they may also be source(s) of off-flavor(s) in vitamin fortified milk due to their heat, oxygen, and the light sensitivity. It is very important for the dairy industry to understand how vitamin concentrates can impact flavor and flavor stability of fluid milk. Currently, little research on vitamin degradation products can be found with respect to flavor contributions. In this review, the history, regulations, processing, and storage stability of vitamins in fluid milk are addressed along with some hypotheses for the role of vitamin A and D fortification on flavor and stability of fluid milk.

Background Thalassemia and haemoglobinopathies pose a huge burden on Indian population, especially in Eastern India. Several studies indicated that abnormal hemoglobin variants influence Hb A1c estimation by High Performance Liquid Chromatography (HPLC) in patients with haemoglobinopathies. We opted capillary electrophoresis (CE) as an alternative method for Hb A1c measurement and aimed to evaluate Hb A1c test results done by (HPLC) with capillary electrophoresis (CE) to rule out the interference caused by abnormal hemoglobin variants. Methods A total of 3000 patients were tested for haemoglobinopathy in our laboratory from (1st -31th) January, 2025. Haemoglobinopathy were screened by Bio-Rad Variant II hemoglobin testing system. Both HPLC and CE methods were employed for Hb A1C testing in the group of patients (137/3000) with haemoglobinopathy using Bio-Rad Variant II Turbo and Sebia Minicap Flex Piercing respectively. Reference range defined for Hb A1c by HPLC: Non-diabetic: 4-5.7, Pre-Diabetic:5.7-6.4, Diabetic =6.5 and reference range for HbA1C by CE: &amp;lt;6 %. Statistical interpretation by was done by SPSS version 26.0. P value less than 0.05 was considered as significant. Statistical correlation was obtained by using Linear regression study. Results : 4.5% (137/3000) of total patients were reported to have abnormal hemoglobin variants in their HPLC chromatogram. 52% (72/137) Hb E carrier, 7.2% (10/137) homozygous E, 23.3% (32/137) beta thalassemia carriers, 1.4% (2/137) beta thalassemia major, 7.2% (10/137) Hb S carrier, 1.4% (2/137) homozygous S ,5.1% (7/137) Hb D carrier and 1.4% (2/137) HPFH (hereditary persistence of fetal hemoglobin) carrier comprised the group of haemoglobinopathies. We compared Hb A1c test results measured by HPLC and CE techniques. Hb A1c test values measured by using both the techniques were observed to be within reference range (Mean±SD: 5.24±1.05 by HPLC, Mean±SD: 5.19±1.08 by CE) in all patients with haemoglobinopathy. Hb A1c tests conducted in patients with haemoglobinopathies by HPLC and CE methods showed strong correlation in test results (Hb E trait: r=0.75 at p =0.01; beta thalassaemia traits: r=0.89 at p=0.04; Hb D: r=0.94 at p=0.2 Hb S: r=0.78 at p=0.21). In contrast to many reported studies, no observable difference was found in Hb A1c values in persons with haemoglobinopathies. HPLC and CE, both the methodologies failed to detect Hb A1c values in homozygous E, homozygous S and beta thalassaemia major patients. The study is limited by less number (n) of participants in each category which might attribute to high p value for determining level of significance. Conclusion Hb A1c test results done by HPLC and CE were in perfect concordance with each other. No such interference by abnormal haemoglobin variants on Hb A1c test results was observed in our study using HPLC method. Replacement of HPLC by CE as an alternative methodology is not necessitated rather both the methods can interchangeably be used for Hb A1c testing in patients with haemoglobinopathies. However, the present study is limited with small number of patients. An extensive study with larger participants is planned to validate the results claimed by our pilot study.

The effect of copper, compared with lead salt-based ballistic modie ers on the reaction of the propellant stabilizers, para-nitro-N-methylaniline and 2-nitrodiphenylamine, during the aging of nitroglycerin solutions and on the reactions of these stabilizers with the individual reactive species known to be generated during double-base propellant decomposition, namely NO 2, HNO2, and HNO3, have been thoroughly investigated in an attempt to deduce some key parameters that ine uence the reactions that take place in these propellant systems during aging. It was found that copper modie ers greatly differ from lead ones in their effect on the depletion of stabilizers and in their reactivity toward the reactive species. All of the copper salts have a dramatic effect on the reactions of propellant stabilizers. They cause more rapid depletion of stabilizers when compared with that produced by lead salts, the effect of basic copper salicylate being more dramatic than that of copper oxide. The results have shown thattheorganicmoiety oftheballisticmodie erplaysanimportantroleinitsine uenceonthereactionsofstabilizers with propellant degradation species, and that the higher reactivity of copper salts compared with that of lead salts is attributable to the combined effect of both the copper ion and the salt anion. In particular, this investigation has helped contribute information on the propellant compositions that should fule ll the requirements for propellant service use. To overcome the deleterious effect of some copper modie ers on the chemical stability of double-base propellants, the stabilizer system must include resorcinol and the copper salt should be used at a low level. OPPER salts, in combination with lead salt-based ballistic modie ers, are used in nitroglycerin-(NC)-based propellants to modify the combustion characteristics of solid rocket propellants. Nearly all solid propellants based on nitrate esters contain a uniformly distributed stabilizer. The function of the stabilizer is the removal of NO 2, which is formed as a primary decomposition product during the storage of propellants, 1 and which would otherwise autocatalytically accelerate the decomposition. Stabilizer mixture systems are widely used in double-base rocket propellant formulations,wheretheyhavebeenfound 2 tobemosteffectiveinprolonging the crack-free life of the propellant grain during storage. It is generally assumed that the more reactive stabilizer reacts rapidly with the propellantdegradation productsduring theearly stagesofaging, whereas the second stabilizer reacts more slowly. Stabilizerslikeresorcinol,andthe combinationofresorcinolwith other stabilizers, are reported to be useful. 3,4 The effectiveness of resorcinolhasbeenexplained 5 asbeingaresultofactivatedaromatic ring formation, which helps in the absorption of nitrogen oxides quickly and more effectively, resulting in further control of growth of autocatalytic reactions. It was indicated 6 that the chemical stability of double-base propellants is signie cantly ine uenced by different lead-based ballistic modie ers, and that the organic moiety of the ballistic modie er is an important ine uence on the reactions of the stabilizers. In this work, systematic investigations have been carried out to obtain a deeper insight into 1 ) a comparison of the effect of lead and copper salt-based modie ers on the reaction of stabilizers commonly used in the cast double-base (CDB) rocket propellants, namely para-nitro-N-methylaniline (pNMA) and 2-nitrodiphenylamine (2NDPA),duringtheagingofNGsolutionsin acetonitrile-containing identical quantities of the ballistic modie ers that are also commonly used in the propellant matrix, and 2 )a study of the effect of copper modie ers on the reactions of the stabilizers with propellant degradation products (namelyNO2, HNO2, and HNO3). Studying the reaction of these compounds is very impor

Determination of pioglitazone hydrochloride in bulk and pharmaceutical formulations by HPLC and MEKC methods

High performance liquid chromatographic (HPLC) and UV derivative spectrophotometric (UVDS) methods were developed and validated for the quantitative determination of sotalol hydrochloride in tablets. The HPLC method was performed on a C18 column with fluorescence detection. The excitation and emission wavelengths were 235 and 310 nm, respectively. The mobile phase was composed of acetonitrile-water containing 0.1% trietylamine (7:93 v/v) and pH adjusted to 4.6 with formic acid. The UVDS method was performed taking a signal at 239.1 nm in the first derivative. The correlation coefficients (r) obtained were 0.9998 and 0.9997 for HPLC and UVDS methods, respectively. The proposed methods are simple and adaptable to routine analysis.

A study of the gross compositions of oil-bearing fluid inclusions using high performance liquid chromatography

HPLC and GC methods development for the analysis of key intermediate for synthesis of dicamba