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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Discovery and quantification of proteins of biological relevance through differential proteomics and biosensing

Lonardoni, Francesco January 2012 (has links)
Medical diagnosis is the process of attempting to determine and/or identify a possible disease or disorder. This process is revealed by biomarkers, defined by The Food and Drug Administration (FDA) as “characteristics that are objectively measured and evaluated as indicators of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention”. The process of biomarker discovery has been boosted in the last years by proteomics, a research discipline that takes a snapshot of the entire wealth of proteins in an organism/ tissue/ cell/ body fluid. An implementation of the analysis methods can help in isolate proteins present in the low range of concentrations, such as biomarkers very often are. An established biomarker can further be measured with the help of biosensors, devices that can be employed in the point-of care diagnostics. This PhD thesis shows and discusses the results of three projects in the field of protein biomarkers discovery and quantification. The first project exploited proteomics techniques to find relevant protein markers for Intrauterine Growth Restriction (IUGR) in cordonal blood serum (UCS) and amniotic fluid (AF). A 14 proteins in UCS and 11 in AF were successfully identified and found to be differentially expressed. Molecularly Imprinted Polymers (MIPs) directed towards proteins and peptides containing phosphotyrosine were then produced, with the final goal of selectively extracting phosphopeptides from a peptide mixture. An alteration of the phosphorylation pattern is in fact often associated to important diseases such as cancer. The polymers were produced as nanoparticles, that were characterised with Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM). A recipe was also tested for binding capacity towards phosphotyrosine. A Surface Plasmon Resonance (SPR) biosensor to quantify hepcidin hormone was finally produced. This is the major subject in iron homeostasis in vertebrates and marker of iron unbalance diseases. A calibration curve was made and affinity/kinetic parameters for the ligand employed were measured.
2

Status de ferro em pacientes com insuficiência cardíaca avançada / Iron status of patients with advanced heart failure.

Silva, Jéssica Helena da 05 August 2013 (has links)
O objetivo deste trabalho foi avaliar o status de ferro (Fe) em pacientes hospitalizados por insuficiência cardíaca avançada. Participaram do estudo 50 pacientes, sendo que 24 foram diagnosticados com anemia e desses 8 apresentam anemia por deficiência de ferro. Foram incluídos no estudo indivíduos do sexo masculino, com idade entre 30 e 60 anos e fração de ejeção do ventrículo esquerdo (FEVE) <0,45. Para análise dos níveis séricos de hepcidina, interleucina 6 (IL-6), fator de necrose tumoral-alfa (TNF-&#945;) e eritropoietina os pacientes foram submetidos a coleta de sangue após jejum de 8 horas. Os parâmetros hematológicos e bioquímicos foram avaliados por meio dos resultados de exames laboratoriais rotineiramente realizados e foram verificados em prontuário médico. O consumo alimentar foi avaliado pelo método direto de pesagem dos alimentos. Os resultados entre os grupos foram comparados pelo teste de Mann Whitney e foram feitas correlações de acordo com o teste de Spearman e teste de Pearson. Não foram encontradas diferenças nos níveis séricos de hepcidina entre os anêmicos com e sem deficiência de ferro. Houve correlação negativa entre a concentração de hepcidina e a de ferritina entre os anêmicos com deficiência de ferro e não foi observada correlações da hepcidina com os outros parâmetros inflamatórios. A desnutrição e a baixa ingestão calórica foram frequentes e não foi verificada baixa ingestão alimentar de ferro. Não foi caracterizada anemia de doença crônica com base na concentração sérica de hepcidina. / The aim of this study was to evaluate the iron status in hospitalized with advanced heart failure. 50 patients participated of this study, 24 of them have been diagnosed with anemia and among these 8 were identified with iron deficiency anemia. Males, aged between 30 and 60 years old, with left ventricular ejection fraction (LVEF) <0,45 were include in the study. For analysis of serum levels of hepcidin, interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-&#945;) and erythropoietin patients underwent blood collection after 8 hours fasting. Haematological and biochemical parameters were obtained laboratory tests routinely performed and were checked in medical records. Food consumption was evaluated by direct weighing method. The results the groups anemic and nonanemic with or without iron deficiency groups were compared by Mann Whitney test and correlations was made according to the Spearman`s and Pearson`s tests. No differences were found in serum hepcidin levels between anemic patients with or without Fe deficiency. There was a negative correlation between hepcidin and ferritin iron-deficiency patients, and correlations of hepcidin with other inflammatory factors were not significant. Malnutrition and low caloric intake were frequent and dietary intake of iron intake was adequate. Chronic disease anemia was not characterized based on serum hepcidin.
3

Status de ferro em pacientes com insuficiência cardíaca avançada / Iron status of patients with advanced heart failure.

Jéssica Helena da Silva 05 August 2013 (has links)
O objetivo deste trabalho foi avaliar o status de ferro (Fe) em pacientes hospitalizados por insuficiência cardíaca avançada. Participaram do estudo 50 pacientes, sendo que 24 foram diagnosticados com anemia e desses 8 apresentam anemia por deficiência de ferro. Foram incluídos no estudo indivíduos do sexo masculino, com idade entre 30 e 60 anos e fração de ejeção do ventrículo esquerdo (FEVE) <0,45. Para análise dos níveis séricos de hepcidina, interleucina 6 (IL-6), fator de necrose tumoral-alfa (TNF-&#945;) e eritropoietina os pacientes foram submetidos a coleta de sangue após jejum de 8 horas. Os parâmetros hematológicos e bioquímicos foram avaliados por meio dos resultados de exames laboratoriais rotineiramente realizados e foram verificados em prontuário médico. O consumo alimentar foi avaliado pelo método direto de pesagem dos alimentos. Os resultados entre os grupos foram comparados pelo teste de Mann Whitney e foram feitas correlações de acordo com o teste de Spearman e teste de Pearson. Não foram encontradas diferenças nos níveis séricos de hepcidina entre os anêmicos com e sem deficiência de ferro. Houve correlação negativa entre a concentração de hepcidina e a de ferritina entre os anêmicos com deficiência de ferro e não foi observada correlações da hepcidina com os outros parâmetros inflamatórios. A desnutrição e a baixa ingestão calórica foram frequentes e não foi verificada baixa ingestão alimentar de ferro. Não foi caracterizada anemia de doença crônica com base na concentração sérica de hepcidina. / The aim of this study was to evaluate the iron status in hospitalized with advanced heart failure. 50 patients participated of this study, 24 of them have been diagnosed with anemia and among these 8 were identified with iron deficiency anemia. Males, aged between 30 and 60 years old, with left ventricular ejection fraction (LVEF) <0,45 were include in the study. For analysis of serum levels of hepcidin, interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-&#945;) and erythropoietin patients underwent blood collection after 8 hours fasting. Haematological and biochemical parameters were obtained laboratory tests routinely performed and were checked in medical records. Food consumption was evaluated by direct weighing method. The results the groups anemic and nonanemic with or without iron deficiency groups were compared by Mann Whitney test and correlations was made according to the Spearman`s and Pearson`s tests. No differences were found in serum hepcidin levels between anemic patients with or without Fe deficiency. There was a negative correlation between hepcidin and ferritin iron-deficiency patients, and correlations of hepcidin with other inflammatory factors were not significant. Malnutrition and low caloric intake were frequent and dietary intake of iron intake was adequate. Chronic disease anemia was not characterized based on serum hepcidin.
4

Avaliação molecular e bioquímica do metabolismo do ferro em pacientes portadores de síndrome metabólica

Rauber, Mariana Reis January 2014 (has links)
Introdução: A síndrome metabólica (SM) apresenta elevada prevalência na população mundial, sendo a hiperferritinemia um achado frequente nestes pacientes. A investigação do aumento da ferritina nesta doença representa um desafio diagnóstico, muitas vezes necessitando exames de alto custo, mas sendo fundamental para identificação dos pacientes que apresentam sobrecarga de ferro. Objetivo: Avaliar os parâmetros bioquímicos e moleculares relacionados ao metabolismo do ferro em pacientes portadores de SM. Métodos: Através de um estudo transversal, foram avaliados 94 pacientes portadores de SM de acordo com os critérios da International Diabetes Federation que estavam em acompanhamento no ambulatório de Medicina Interna do HCPA. Foram avaliados dados antropométricos e de diagnóstico para SM, dosagem de ferro, ferritina, a saturação da transferrina, hepcidina, além das mutações C282Y e H63D do gene HFE da hemocromatose. Resultados: A prevalência de hiperferritinemia na população em estudo foi de 27,7%, sendo maior no sexo masculino (53,8%) que no sexo feminino (14,5%) (p<0,001). A elevação da saturação de transferrina, e não da ferritina, se correlacionou com mutações do gene da hemocromatose. A hiperferritinemia se associou com saturação de transferrina (p<0,001) e a hepcidina (p=0,008), após análise de regressão logística. Conclusão: A hiperferritinemia é um achado frequente na SM, sendo mais comum em homens. A dosagem da saturação de transferrina é um bom parâmetro para screening de pacientes com mutação da hemocromatose, como já demonstrado na literatura. Sugere-se a hepcidina como um novo biomarcador com potencial promissor na investigação da hiperferritinemia associada à SM. / Introduction: Metabolic syndrome (MS) has a high prevalence in the world population, and hyperferritinemia is a frequent finding in these patients. The investigation of the increased ferritin in this syndrome represents a diagnostic challenge, often requiring expensive tests, but is essential for identification of patients with iron overload. Objective: To evaluate biochemical and molecular parameters related to iron metabolism in patients with MS. Methods: In a cross-sectional study, we evaluated 94 patients with MS according to the criteria of the International Diabetes Federation who were accompanied in the outpatient clinics of internal medicine, Hospital de Clínicas de Porto Alegre. We evaluated anthropometric data and diagnostic criteria for MS, iron dosage, ferritin, transferrin saturation, hepcidin, besides the C282Y and H63D mutations in the HFE hemochromatosis gene. Results: The prevalence of hyperferritinemia in the study population was 27.7% and was higher in males (53.8%) than in females (14.5%) (p <0.001). The elevation of transferrin saturation, but not ferritin, did relate with mutations the hemochromatosis gene. Hyperferritinemia related to transferrin saturation (p <0.001) and hepcidin (p = 0.008) after logistic regression analysis. Conclusion: Hyperferritinemia is a frequent finding in metabolic syndrome, most frequently in men. Determination of transferrin saturation is a good parameter for screening of patients with hemochromatosis mutation, as already demonstrated in literature. It is suggested hepcidin as a new biomarker with promising potential in research hyperferritinemia associated with MS.
5

Avaliação molecular e bioquímica do metabolismo do ferro em pacientes portadores de síndrome metabólica

Rauber, Mariana Reis January 2014 (has links)
Introdução: A síndrome metabólica (SM) apresenta elevada prevalência na população mundial, sendo a hiperferritinemia um achado frequente nestes pacientes. A investigação do aumento da ferritina nesta doença representa um desafio diagnóstico, muitas vezes necessitando exames de alto custo, mas sendo fundamental para identificação dos pacientes que apresentam sobrecarga de ferro. Objetivo: Avaliar os parâmetros bioquímicos e moleculares relacionados ao metabolismo do ferro em pacientes portadores de SM. Métodos: Através de um estudo transversal, foram avaliados 94 pacientes portadores de SM de acordo com os critérios da International Diabetes Federation que estavam em acompanhamento no ambulatório de Medicina Interna do HCPA. Foram avaliados dados antropométricos e de diagnóstico para SM, dosagem de ferro, ferritina, a saturação da transferrina, hepcidina, além das mutações C282Y e H63D do gene HFE da hemocromatose. Resultados: A prevalência de hiperferritinemia na população em estudo foi de 27,7%, sendo maior no sexo masculino (53,8%) que no sexo feminino (14,5%) (p<0,001). A elevação da saturação de transferrina, e não da ferritina, se correlacionou com mutações do gene da hemocromatose. A hiperferritinemia se associou com saturação de transferrina (p<0,001) e a hepcidina (p=0,008), após análise de regressão logística. Conclusão: A hiperferritinemia é um achado frequente na SM, sendo mais comum em homens. A dosagem da saturação de transferrina é um bom parâmetro para screening de pacientes com mutação da hemocromatose, como já demonstrado na literatura. Sugere-se a hepcidina como um novo biomarcador com potencial promissor na investigação da hiperferritinemia associada à SM. / Introduction: Metabolic syndrome (MS) has a high prevalence in the world population, and hyperferritinemia is a frequent finding in these patients. The investigation of the increased ferritin in this syndrome represents a diagnostic challenge, often requiring expensive tests, but is essential for identification of patients with iron overload. Objective: To evaluate biochemical and molecular parameters related to iron metabolism in patients with MS. Methods: In a cross-sectional study, we evaluated 94 patients with MS according to the criteria of the International Diabetes Federation who were accompanied in the outpatient clinics of internal medicine, Hospital de Clínicas de Porto Alegre. We evaluated anthropometric data and diagnostic criteria for MS, iron dosage, ferritin, transferrin saturation, hepcidin, besides the C282Y and H63D mutations in the HFE hemochromatosis gene. Results: The prevalence of hyperferritinemia in the study population was 27.7% and was higher in males (53.8%) than in females (14.5%) (p <0.001). The elevation of transferrin saturation, but not ferritin, did relate with mutations the hemochromatosis gene. Hyperferritinemia related to transferrin saturation (p <0.001) and hepcidin (p = 0.008) after logistic regression analysis. Conclusion: Hyperferritinemia is a frequent finding in metabolic syndrome, most frequently in men. Determination of transferrin saturation is a good parameter for screening of patients with hemochromatosis mutation, as already demonstrated in literature. It is suggested hepcidin as a new biomarker with promising potential in research hyperferritinemia associated with MS.
6

Avaliação molecular e bioquímica do metabolismo do ferro em pacientes portadores de síndrome metabólica

Rauber, Mariana Reis January 2014 (has links)
Introdução: A síndrome metabólica (SM) apresenta elevada prevalência na população mundial, sendo a hiperferritinemia um achado frequente nestes pacientes. A investigação do aumento da ferritina nesta doença representa um desafio diagnóstico, muitas vezes necessitando exames de alto custo, mas sendo fundamental para identificação dos pacientes que apresentam sobrecarga de ferro. Objetivo: Avaliar os parâmetros bioquímicos e moleculares relacionados ao metabolismo do ferro em pacientes portadores de SM. Métodos: Através de um estudo transversal, foram avaliados 94 pacientes portadores de SM de acordo com os critérios da International Diabetes Federation que estavam em acompanhamento no ambulatório de Medicina Interna do HCPA. Foram avaliados dados antropométricos e de diagnóstico para SM, dosagem de ferro, ferritina, a saturação da transferrina, hepcidina, além das mutações C282Y e H63D do gene HFE da hemocromatose. Resultados: A prevalência de hiperferritinemia na população em estudo foi de 27,7%, sendo maior no sexo masculino (53,8%) que no sexo feminino (14,5%) (p<0,001). A elevação da saturação de transferrina, e não da ferritina, se correlacionou com mutações do gene da hemocromatose. A hiperferritinemia se associou com saturação de transferrina (p<0,001) e a hepcidina (p=0,008), após análise de regressão logística. Conclusão: A hiperferritinemia é um achado frequente na SM, sendo mais comum em homens. A dosagem da saturação de transferrina é um bom parâmetro para screening de pacientes com mutação da hemocromatose, como já demonstrado na literatura. Sugere-se a hepcidina como um novo biomarcador com potencial promissor na investigação da hiperferritinemia associada à SM. / Introduction: Metabolic syndrome (MS) has a high prevalence in the world population, and hyperferritinemia is a frequent finding in these patients. The investigation of the increased ferritin in this syndrome represents a diagnostic challenge, often requiring expensive tests, but is essential for identification of patients with iron overload. Objective: To evaluate biochemical and molecular parameters related to iron metabolism in patients with MS. Methods: In a cross-sectional study, we evaluated 94 patients with MS according to the criteria of the International Diabetes Federation who were accompanied in the outpatient clinics of internal medicine, Hospital de Clínicas de Porto Alegre. We evaluated anthropometric data and diagnostic criteria for MS, iron dosage, ferritin, transferrin saturation, hepcidin, besides the C282Y and H63D mutations in the HFE hemochromatosis gene. Results: The prevalence of hyperferritinemia in the study population was 27.7% and was higher in males (53.8%) than in females (14.5%) (p <0.001). The elevation of transferrin saturation, but not ferritin, did relate with mutations the hemochromatosis gene. Hyperferritinemia related to transferrin saturation (p <0.001) and hepcidin (p = 0.008) after logistic regression analysis. Conclusion: Hyperferritinemia is a frequent finding in metabolic syndrome, most frequently in men. Determination of transferrin saturation is a good parameter for screening of patients with hemochromatosis mutation, as already demonstrated in literature. It is suggested hepcidin as a new biomarker with promising potential in research hyperferritinemia associated with MS.
7

Separace hepcidinu na magnetických sorbentech s následnou analýzou pomocí MALDI-TOF-MSí / Separation of hepcidin using magnetic sorbents with subsequent MALDI-TOF MS analysis

Vávrová, Jana January 2010 (has links)
Hepcidin is cysteine-rich cationic peptide produced by hepatocytes, secreted into blood plasma, and excreted in urine. Hepcidin is proposed to be the key regulator of iron metabolism and an evaluation of changes in the hepcidin level is important for diagnosis of several diseases. However, methods used for the hepcidin detection and determination in urine and serum have certain limitations. At present time MALDI-TOF MS based approaches have been applied for final analysis of urinary and/or serum hepcidin levels. Before MS analysis, separation of hepcidin from analyzed samples is an important and necessary step. The aim of this study was to compare the ability of several magnetic sorbents with different coating matrix and/or different terminal functionalized groups to adsorb hepcidin prior MS analysis. Either commercial magnetic sorbents containing -COOH groups or magnetic hydrophilic IDA-modified polymethacrylate microparticles P(HEMA-co-GMA)-IDA with immobilized metal ions were use for this purpose. Hepcidin was adsorbed to magnetic sorbents containing linked carboxyl groups (i.e. to weak cation exchange magnetic particles) at pH 6.8 independently on a nature of magnetic particle coating layer. Magnetic particles P(HEMA-co- GMA)-IDA with immobilized Cu(II) ions were found to adsorb hepcidin in a...
8

Discovery of an Allosteric Site on Furin, contributing to Potent Inhibition: A Promising Therapeutic for the Anemia of Chronic Inflammation

Gross, Andrew Jacob 01 July 2014 (has links)
Release Date: October 2017 Anemia of chronic inflammation (ACI) is a condition that develops in a setting of chronic immune activation. ACI is characterized and triggered by inflammatory cytokines and the disruption of iron homeostasis. Hepcidin, a small peptide hormone, is the master regulator of iron homeostasis, and rapidly responds to iron supply and demand. Under conditions of chronic inflammation, hepcidin is elevated, and alters the way that iron is absorbed and disrupted throughout the body, resulting in disrupted iron homeostasis through inhibition of the iron exporter protein ferroportin. Anemia arises when insufficient erythropoietic activity combined with inadequate iron supply abrogates the healthy development of mature red blood cells (RBCs). The proprotein convertase (PC) known as furin is a serine protease capable of cleaving peptide precursors into their active state. Furin is critical for normal activation of proteins and enzymes but recently, furin has been implicated in critical roles within cancers, viral and pathogenic infections, and arthritis through activating precursors novel to the disease type. Furin has previously been identified as being the sole PC responsible for generating active hepcidin. Hepcidin is initially synthesized as a larger precursor protein, before undergoing furin cleavage. Furin is known to form mature, bioactive hepcidin, with the removal of this pro-region. Our discovery of a novel regulatory site on Furin has led to potent inhibition using small molecules. This inhibition is shown with the use of in vitro fluorogenic assays, in vivo cell tissue cultures, and within an animal model of ACI. Our results demonstrate that in using these small molecules we can decrease hepcidin levels even in the presence of potent inflammatory cytokines. The inhibition of hepcidin by these small molecules causes an increase in stably expressed ferroportin on cell surfaces and the restoration of the ability to mobilize iron from storage tissues and absorption from the diet. The ability to "fine-tune" inhibition of furin in targeting its allosteric site along with its catalytic domain designates these small-molecule inhibitors as promising therapeutics for treatment of diseases ranging from Alzheimer's and cancer to anthrax and Ebola fever.
9

Transcriptional regulation of hepcidin by molecules mediating inflammatory responses / 炎症反応仲介分子によるヘプシジン転写の調節

Kanamori, Yohei 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21135号 / 農博第2261号 / 新制||農||1057(附属図書館) / 学位論文||H30||N5109(農学部図書室) / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 松井 徹, 教授 久米 新一, 教授 廣岡 博之 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
10

Development of LC-MS/MS methods for the quantitative determination of hepcidin-25, a key regulator of iron metabolism

Abbas, Ioana 24 August 2018 (has links)
Hepcidin-25, ein 2000 entdecktes Peptidhormon, das eine Schlüsselrolle im Eisenstoffwechsel spielt, hat das Verständnis von Eisenerkrankungen revolutioniert. In dieser Studie wurde LC gekoppelt mit einem Triple-Quadrupol MS in einer schnellen und robusten Methode zur Quantifizierung von Hepcidin-25 in menschlichem Serum verwendet, welche letztlich in Routine-Laboratorien genutzt werden soll. Zu diesem Zweck wurden zwei Probenvorbereitungsstrategien und zwei komplementäre LC Bedingungen untersucht, wobei eine saure mobile Phase (0,1% TFA) mit einem neuartigen Ansatz unter der Verwendung einer basischen mobilen Phase (0,1% NH3) verglichen wurde. In einem laborinternen Vergleich beider LC-MS/MS Methoden wurde Hepcidin-25 in humanen Proben unter Verwendung der gleichen Kalibrierstandards quantifiziert und eine sehr gute Korrelation der Ergebnisse ermittelt. Hierbei wurde die Analysestrategie mit saurer mobiler Phase als hochsensitiv (LOQ von 0,5 μg/L) und präzise (CV <15%) befunden und als Kandidat einer Referenzmethoden für die Hepcidin-25 Quantifizierung in realen Proben empfohlen. Einer der neuartigen Aspekte der Methodik war die Verwendung von Amino- und Fluor-silanisierten Autosampler-Fläschchen, um die Adsorption des 25 Reste umfassenden Peptids anOberflächen zu reduzieren. Darüber hinaus wurde diese LC-MS/MS-Methode in einer internationalen Ringversuchsstudie eingesetzt, bei der ein sekundäres Referenzmaterial als Kalibrierstandard verwendet wurde, und gemäß des International Consortium for Harmonization of Clinical Laboratory Results (ICHCLR) als optimal bewertet. In dieser Arbeit wurde die Bildung von Hepcidin-Komplexen mit Kupfer(II) untersucht. Die erste Umkehrphasen-chromatographische Trennung von Hepcidin-25/Cu(II) und Hepcidin-25 (Kupfer "frei") wurde unter Verwendung von mobilen Phasen mit 0,1% NH3 erreicht. LC-MS/MS und FTICR-MS wurden für die Charakterisierung der gebildeten Hepcidin-25-Cu(II)-Spezies bei pH-Werten von 11 bzw. 7,4 verwendet. / Hepcidin-25, a key iron-regulatory peptide hormone discovered in 2000, has revolutionized the understanding of iron-related pathology. This study applied LC-MS/MS, using the triple quadrupole mass spectrometer, in a rapid and robust analytical strategy for the quantification of hepcidin-25 in human serum, to be implemented in routine laboratories. For this purpose, two sample preparation strategies and two complementary LC conditions were investigated, where the use of acidic mobile phases (0.1% TFA) was compared with a novel approach involving solvents at high pH (0.1% NH3). The application of these LC-MS/MS methods to human samples in an intra-laboratory comparison, using the same hepcidin-25 calibrators, yielded a very good correlation of the results. The LC-MS/MS employing trifluoroacetic acid-based mobile phases was selected as a highly sensitive (LOQ of 0.5 µg/L) and precise (CV<15%) method and was recommended as a reference method candidate for hepcidin-25 quantification in real samples. One of the novel aspects of the methodology was the use of amino- and fluoro-silanized autosampler vials to reduce the interaction of the 25-residue peptide to laboratory glassware surfaces. Moreover, this LC-MS/MS method was used for an international round robin study, applying a secondary reference material as a calibrator and its performance was found to be in the optimal range as defined by the International Consortium for Harmonization of Clinical Laboratory Results (ICHCLR). In this work, the formation of hepcidin-25 complexes with copper(II) was investigated. The first reversed-phase chromatographic separation of hepcidin-25/Cu2+ and hepcidin-25 (copper “free”) was achieved by applying mobile phases containing 0.1% NH3. LC-MS/MS and FTICR-MS were applied for the characterization of the formed hepcidin-25-Cu(II) species at pH values of 11 and 7.4 respectively. A new species corresponding to hepcidin-25 complexed with two copper ions was identified at high pH.

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