Catecholamines In Human Urine Research Articles

Enhanced detection of catecholamines in human urine using Cis-diol-microporous organic networks with PT-SPE and HPLC-MS/MS

A novel cis-diol-microporous organic networks (MONs-2OH) material was synthesized via room temperature and Sonogashira coupling reactions, which exhibits exceptional adsorption properties for catecholamines (CAs). MONs-2OH demonstrates robust hydrogen bonding and π-π stacking interactions, crucial for effective adsorption. The MONs-2OH was incorporated into pipette tip solid-phase extraction and developed a new method for detecting CAs in human urine using HPLC-MS/MS. Characterization of the adsorbent revealed its high stability, large specific surface area, abundant phenolic hydroxyl groups, rapid extraction speed, and superior adsorption efficiency. The method achieved a wide linear range (0.5–500 ng/mL), low detection limits (0.06–0.26 ng/mL), high accuracy (90.4 %-99.4 %), and excellent precision (RSD ≤ 10 %). Comparative studies showed MONs-2OH outperforms commercial adsorbents in terms of recovery and adsorption capacity. The results underscore the potential of MONs-2OH for rapid and sensitive CAs determination, offering significant advantages for the auxiliary diagnosis of depression and enhancing the application of PT-SPE in sample pretreatment.

Tannic acid-directed synthesis of magnetic and boronic acid-functionalized metal-organic frameworks for selective extraction and quantification of catecholamines in human urine.

Anovel magnetic borate-functionalized metal-organic framework nanocomposite was designed and fabricated for selective enrichment of catecholamines from human urine. Firstly, the polytannic acid (PTA) layer with natural low-cost and ecofriendly polyphenol tannic acid as the organic ligand and Fe3+ as the cross-linker was coated onto the surface of Fe3O4. Then, the borate-functionalized metal-organic framework (MIL-100(Fe)-B) with 5-boronobenzene-1,3-dicarboxylic acid as a ligand fragment was modified onto the PTA-coated Fe3O4 through a metal-ligand-fragment coassembly strategy. The obtained smart porous adsorbent Fe3O4@PTA@MIL-100(Fe)-B was confirmed by means of several characterization methods and then applied as an effective magnetic solid phase extraction (MSPE) sorbent for specific extraction of trace catecholamines in human urine. The Plackett-Burman design was used for screening the variables significantly affecting the extraction efficiency. Then, the significant factors were further investigated by the Box-Behnken design to determine the optimal extraction conditions. Under the optimal conditions, a method for selective MSPE combined with high-performance liquid chromatography with a fluorescence detector for the quantitation of catecholamines in human urine was developed and validated. With the proposed method, the linearity range was from 0.500 to 500ngmL-1 for norepinephrine and epinephrine and from 1.00 to 500ngmL-1 for dopamine. The detection limits were 0.050, 0.11, and 0.20ngmL-1 for norepinephrine, epinephrine, and dopamine, respectively. The recoveries from spiking experiments varied from 91.5 to 108% with relative standard deviations (RSDs) of 0.80-4.8%. The established method israpid, sensitive, accurate, inexpensive, and ecofriendly and was successfully applied to the determination of the target catecholamines in human urine samples.

Polyvinyl butyral/graphene oxide nanocomposite modified electrode for the integrate determination of terminal metabolites of catecholamines in human urine

We for the first time reported the development of an electrochemical sensor with polyvinyl butyral/graphene oxide (PVB/GO) nanocomposite film for the integrate determination of major terminal metabolites of catecholamines. The PVB/GO nanocomposite modified electrode was characterized by ATR-FTIR spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), scanning probe microscopy (SPM) and electrochemical impedance spectroscopy (EIS). The PVB/GO-modified glassy carbon electrode exhibits a good affinity and electrocatalytic activity to the oxidation of homovanillic acid (HVA) and vanillylmandelic acid (VMA), and the two terminal metabolites showed nearly consistent peak potentials at the modified electrode by differential pulse voltammetry (DPV). The performance of the developed sensor was evaluated in terms of linearity, precision, stability, repeatability and recovery for the determination of HVA/VMA. The electrode enables the ‘equivalent’ determination over the ranges of 0.549–120μM with a detection limit (LOD) of 0.18μM for HVA and 0.75–120μM with a detection limit of 0.25μM for VMA, respectively. The proposed sensor has the advantages of low cost, well stability, and high sensitivity. It was successfully applied to the integrate determination of the terminal metabolites of catecholamines in human urine.

New Approach to the Formation of Physically Adsorbed Capillary Coatings Consisting of Hyperbranched Poly(Ethylene Imine) with a Maltose Shell to Enhance the Separation of Catecholamines and Proteins in CE

Core–shell-type polymers based on a hyperbranched (hb) poly(ethylenimine) core and a shell with a variable maltose content were applied as coating materials for fused silica capillaries. A new, simple, fast, and reproducible way of modifying the capillary walls through the physical adsorption of the core–shell-type polymers using a Cu2+ support was developed. The coating created by this method was found to be very stable compared to the coating created using a solution of the polymer only. Capillaries modified with the core–shell-type polymers were tested by applying them to the electrophoretic separation of catecholamines and proteins. The modified capillaries showed high efficiencies (up to 800,000 theoretical plates per meter for lysozyme) and separation selectivities. The highest efficiency was achieved using capillaries modified with the polymer containing the lowest content of maltose in the shell and the most accessible positively charged core. Various online concentration techniques were also tested as a means to lower detection limits further, making it possible to analyze proteins in biological fluids (saliva) as well as catecholamines in human urine after SPE using activated alumina.

Facile synthesis of a boronate affinity sorbent from mesoporous nanomagnetic polyhedral oligomeric silsesquioxanes composite and its application for enrichment of catecholamines in human urine

A boronate-decorated nanomagnetic organic-inorganic hybrid material was facilely synthesized by utilizing the nanomagnetic polyhedral oligomeric silsesquioxanes (POSS) composite (Fe3O4@POSS) as the base platform. A simple copolymerization occurred between 3-acrylamidophenylboronic acid (AAPBA) and the residual end vinyl groups supplied by the substrate. Here the special emphasis was placed on the octavinyl POSS, which not only acted as the building blocks for a hybrid architecture but also facilitated the process of grafting boronate groups onto the surface of POSS based nanomagnetic composite (Fe3O4@POSS). The successful immobilization of affinity ligand-AAPBA on the Fe3O4@POSS was confirmed by Fourier transform infrared (FT-IR), elemental analysis, inductively coupled plasma atomic emission spectrometer (ICP-AES), field emission scanning electron microscope. A magnetic solid-phase extraction (MSPE) for cis-diols enrichment was developed using the as-prepared Fe3O4@POSS-AAPBA material as an affinity sorbent and three catecholamines (CAs), namely noradrenaline, epinephrine and isoprenaline, as model analytes. Under the optimal extraction conditions, sensitive and simultaneous analysis of three CAs from the urine sample was achieved by high-performance liquid chromatography with UV detection (HPLC-UV). The limits of detection (LOD, S/N = 3) and the limits of quantitation (LOQ, S/N = 10) for the target analytes were 0.81–1.32 ng mL−1 and 2.70–4.40 ng mL−1, respectively. Also good recoveries (85.5–101.7%) and repeatability (RSD≤10.1%) were obtained by this method. This work not only showed a facility for the utilization of Fe3O4@POSS as a substrate for constructing a boronate functionalized nanomagnetic sorbent, but also demonstrated the capability of the derived material for recognition of trace amount of cis-diols biomolecules presented in complicated biological matrices.

Development and validation of a specific and sensitive LC-MS/MS method for quantification of urinary catecholamines and application in biological variation studies.

Catecholamines are a class of biogenic amines that play an important role as neurotransmitters and hormones. We developed and validated a rapid, specific and sensitive LC-MS/MS method for quantitative determination of catecholamines in human urine. Linearity, specificity, sensitivity, precision, accuracy, matrix effect, carryover, analyte stability, method comparison and reference range were evaluated. The catecholamine measurements were not affected by 35 structurally-related drugs and metabolites. The outstanding specificity was achieved by use of a specific diphenylborate-based solid phase extraction and subsequent selective LC-MS/MS analysis. Excellent sensitivity, accuracy and precision (average intra-assay variations <2.9% and inter-assay variations <4.6%) were obtained. The method was successfully applied in the study of day-to-day biological within- and between-subject variations of 25 healthy people under free-living conditions over three consecutive days. We observed that catecholamine excretions for second morning sampling had least day-to-day within-subject variation and excellent reproducibility. This work is one of the rare studies on these topics and represents the first utilization of advanced LC-MS/MS technology. Additionally, we found significant correlations between spot and conventional 24h collections of human urine (n = 22, r > 0.853, p < 0.0001). These findings suggest that determining the catecholamine concentrations inthe second morning urine sample presents accurate, convenient and reliable measurement of catecholamine excretions. In addition, consistent and significant diurnal variations for norepinephrine and epinephrine excretions were observed during the three-day period, while dopamine did not exhibit a diurnal rhythm. The LC-MS/MS method presented here is rapid, sensitive and specific, which could be an advantage in clinical laboratories.

Determination of catecholamines by ion chromatography coupled to acidic potassium permanganate chemiluminescence detection

A simple, fast, sensitive, highly selective and eco-friendly analytical method for the determination of catecholamines in human urine by ion chromatography (IC) with chemiluminescence (CL) detection was described in this paper. Using 12 mmol/L H2SO4 without any organic additive as eluent, three catecholamines including epinephrine (EP), norepinephrine (NE) and dopamine (DA) were well separated on a cation-exchange column. The CL detection was based on the reaction of analytes with acidic potassium permanganate in the presence of formaldehyde as an enhancer. The absence of methanol and acetonitrile in eluent made the proposed method more sensitive and eco-friendly. Under the optimal conditions, the linear range of the proposed method was in the range of 0.02–0.5 μg/mL. The limit of detection (LOD) was in the range of 0.6 and 5.1 μg/L. The relative standard deviations (RSD) for 0.1 μg/mL mixed standard solution were in the range of 0.8–1.9% (n = 11). The method has been applied to the determination of catecholamines in human urine successfully. Excellent spiked recoveries were achieved for catecholamines ranged from 91.2% to 112.7%.

Determination of three major catecholamines in human urine by capillary zone electrophoresis with chemiluminescence detection

A sensitive simple method is presented for the determination of three major catecholamines in human urine by capillary electrophoresis (CE) with on-line chemiluminescence (CL) detection. This was also the first time that the luminol–Ag(III) complex CL system was used for CE detection. This method was based on the enhancing effect of epinephrine (EP), norepinephrine (NE), and dopamine (DA) on the CL reaction between luminol and the Ag(III) complex in alkaline solution. The separations and determinations were performed with an electrophoretic buffer consisting of 20.0mM sodium borate and 1.0mM luminol. Under optimized conditions, the three catecholamines were baseline separated and detected in less than 8min. Detection limits of 7.9×10−8M, 1.0×10−7M, and 6.9×10−8M were observed for EP, NE, and DA, respectively. Relative standard deviation (RSD) values for the peak height were 4.7% to 5.4% (n=5). Our proposed method was applied to the determinations of the catecholamines in urine samples from 12 healthy individuals and 26 pheochromocytoma patients. Our results suggest that this method might be useful to monitor the catecholamine levels in routine screening and to diagnose pheochromocytoma.

Simultaneous determination of catecholamines and their metabolites related to Alzheimer's disease in human urine

A simple and specific high-performance liquid chromatography method coupled with fluorescence detection (HPLC-FL) has been developed for the simultaneous determination of L-3,4-dihydroxyphenylalanine, norepinephrine, dopamine, epinephrine and 3,4-dihydroxyphenylacetic acid in human urine. The samples were derivatized by 1,2-diphenylethylenediamine with isoprenaline as internal standard. The factors affecting the fluorescence yield were investigated, including the reaction and separation conditions. The catecholamine derivatives were separated on a Kromasil C(18) column with methanol and sodium acetate buffer as mobile phase. The limits of detection for all catecholamines ranged from 0.2 to 1.1 ng/mL. The linear ranges were from 2.5 to 200 ng/mL except 3,4-dihydroxyphenylacetic acid from 5 to 200 ng/mL. The intra- and interday RSDs for all catecholamines were 1.0-8.0 and 2.1-14%, respectively. The method was successfully applied to determine the catecholamines in human urine from 14 Alzheimer's disease patients and 14 healthy volunteers. It was concluded that the mean levels of catecholamines in urine of Alzheimer's disease patients were all lower than those in healthy volunteers. The cluster analysis and independent samples T-test were used to distinguish the Alzheimer's disease patients and healthy volunteers.

Sensitive Analysis of 5-(4,6-Dichloro-s-triazin-2-ylamino)fluorescein-Labeled Catecholamines by Mixed MEKC–LIF

Mixed micellar electrokinetic chromatography with laser-induced fluorescence detection has been used for analysis of the catecholamines norepinephrine, epinephrine, and dopamine. The fluorescent reagent 5-(4,6-dichloro-s-triazin-2-ylamino)fluorescein was used to label the three compounds. The reaction rate increased with increasing alcohol concentration in the derivatization buffer. Under the optimum conditions the derivatization reaction was complete within 10 min. The separation was performed with 40 mM sodium cholate, 30 mM sodium dodecyl sulfate, 30 mM sodium borate (pH 9.6), and acetonitrile 8.0% (v/v) as running buffer. The applied potential was 25 kV and the capillary temperature was 25 °C. The detection limits for norepinephrine, epinephrine, and dopamine were 3.3, 0.25, and 1.26 nM. The method was successfully applied to monitoring of these catecholamines in human urine. Recovery of the three analytes ranged from 93.2 to 105.8%.

Risk-based approach for the transfer of quantitative methods: Bioanalytical applications

The transfer of analytical methods from a sending laboratory to a receiving one requires to guarantee that this last laboratory will obtain accurate results. Undeniably method transfer is the ultimate step before routine implementation of the method at the receiving site. The conventional statistical approaches generally used in this domain which analyze separately the trueness and precision characteristics of the receiver do not achieve this. Therefore, this paper aims first at demonstrating the applicability of two recent statistical approaches using total error-based criterion and taking into account the uncertainty of the true value estimate of the sending laboratory, to the transfer of bioanalytical methods. To achieve this, they were successfully applied to the transfer of two fully automated liquid chromatographic method coupled on-line to solid-phase extraction. The first one was dedicated to the determination of three catecholamines in human urine using electrochemical detection, and the second one to the quantitation of N-methyl-laudanosine in plasma using fluorescence detection. Secondly, a risk-based evaluation is made in order to understand why classical statistical approaches are not sufficient to provide the guarantees that the analytical method will give most of the time accurate results during its routine use. Finally, some recommendations for the transfer studies are proposed.

Capillary electrophoresis with direct chemiluminescence detection for the analysis of catecholamines in human urine

A rapid and sensitive method for the analysis of three catecholamines by capillary electrophoresis (CE) with direct chemiluminescence (CL) detection is described. The detection limits (S/N = 3) were 1.3 × 10 −8 g/mL for isoprenaline, 1.0 × 10 −8 g/mL for epinephrine and 2.8 × 10 −8 g/mL for dopamine. The proposed method was successfully applied to the analysis of catecholamines in urine samples of cigarette smokers and nonsmokers. The results showed that there is a close relation between the release of dopamine in human body fluids and cigarette smoking/nonsmoking.

Validation of a high performance liquid chromatography analysis for the determination of noradrenaline and adrenaline in human urine with an on-line sample purification

A high performance liquid chromatography (HPLC) method with fluorescence detection including an on-line purification was established for determination of catecholamines in human urine. The method was evaluated using samples of pooled urine spiked with catecholamines and validated for measurements of catecholamines in urine of healthy individuals in a field study. The laboratory method evaluation study showed that the recovery of the method was 0.82 (confidence interval (CI): 0.79–0.86) and 0.92 (CI: 0.89–0.95) for noradrenaline and adrenaline, respectively. Thus, correction factors of 0.82 −1 and 0.92 −1 were applied to correct the measurement results for this systematic effect. Furthermore, an uncertainty budget was generated for the analytical method using the BIPM-approach recommended by the International Organization for Standardization. The relative uncertainty of the method was estimated to be 10–12%, which was consistent with the observed relative variability found in the method evaluation. The method was evaluated in accordance with EURACHEM Guidance Document No 1 concerning accreditation for chemical laboratories with respect to accuracy and precision. The field study showed that the standard deviation of the method was sufficiently low to distinguish between persons working with two different processes of garbage collection, i.e. collection using four wheeled containers versus collection using bins.

Aromatic glycinonitriles and methylamines as pre-column fluorescence derivatization reagents for catecholamines

The reactivity of some catecholamines with aromatic glycinonitriles (AGN) (four species) and aromatic methylamines (AMA) (five species) was investigated in detail, to find pre-column fluorescence derivatization reagents for catecholamines. Of the nine reagents tested, 2-phenylglycinonitrile (PGN) and benzylamine (BA) were shown to be the best reagents in terms of selectivity and sensitivity. The reagents react selectively with catecholamines under mild conditions in the presence of ammonium molybdate and sodium periodate for PGN and potassium hexacyanoferrate(III) for BA to give fluorescent derivatives. The derivatives of four catecholamines (epinephrine (E), norepinephrine (NE), dopamine (DA) and isoproterenol (IP)) could be separated within 13 min by reversed-phase liquid chromatography with isocratic elution and measured fluorimetrically. The detection limits ( signal-to-noise ratio = 3) are in the range 5.2–11.0 fmol for PGN and 1.6–100 fmol for BA in a 50 μl injection volume. The liquid chromatographie (LC) methods with PGN and BA were successfully applied to the determination of some catecholamines in human urine.

In-line derivatization method for fluorometric determination of catecholamines by high performance liquid chromatography

A fluorometric method has been developed for the determination of norepinephrine, epinephrine and dopamine by high-performance liquid chromatography. Catecholamines extracted from urine were separated by reversed-phase chromatography with an alkaline mobile phase (pH 8.0, 20 mM sodium tetraborate containing 30 mM 1-butaneboronic acid) and were fluorometrically detected (Ex 400 nm and EM 475 nm) via in-line derivatization at high temperature (100 °C). Retention times for norepinephrine, epinephrine, dopamine and isoproterenol as an internal standard were 8, 10, 13 and 28 min, respectively. Calibration curves for these compounds were linear from 4 to 100 ng/ml standard solution. The detection limit (signalto noise ratio=3) for norepinephrine, epinephrine and dopamine was 0.1, 0.2 and 0.8 ng. The assay of catecholamines in human urine is also described.

Extension of the application of the thermal in-situ reaction on NH2 layers to the detection of catecholamines in biological materials

This article describes a thin-layer chromatographic method for the determination of catecholamines in human urine. Chromatographic separation on NH2-modified silica gel layers is followed by in-situ visualization brought about by heating the plate. The use of this derivatization technique for other urine components, such as creatine, creatinine, uric acid and glucose, is also discussed.

Determination of free catecholamines in human urine by direct injection of urine into a liquid chromatographic column-switching system with fluorimetric detection

An ion-exchange chromatographic method combined with ion exclusion was developed for the determination of free catecholamines in human urine. Catecholamines were separated by ion exclusion from most acidic and neutral impurities by filtration through an anion-exchange column with a hydrophilic matrix (Asahipak ES-502N) and the excluded catecholamines were separated by ion-exchange chromatography on a column of weakly acidic ion exchanger with a hydrophilic matrix (Asahipak ES-502C), connected in series to the Asahipak ES-502N column with a four-way automatic valve. A sodium succinate-borate buffer of pH 6.7 (0.035 mol of succinic acid, 0.0075 mol of borate and 0.5 mmol of ethylenediaminetetraacetate were dissolved in 1 kg of water and the pH of the solution was adjusted to 6.7 with sodium hydroxide) was used as the mobile phase, and the temperature of both columns was kept at 30°C. The catecholamines in the eluate were determined fluorimetrically by post-column derivatization with glycylglycine. A diluted urine sample was injected directly onto the first column. The first column was back-flushed with the mobile phase for 52.5 min after the elution of the catecholamines from the first to the second column. Then the columns were washed with the mobile phase for 10 min in the normal direction before the next sample was injected into the first column. Samples could be analysed every 70 min and 5 pmol/ml of epinephrine, 5 pmol/ml of norepinephrine and 25 pmol/ml of dopamine in human urine could be determined.

Determination of free and total catecholamines in human urine by HPLC with fluorescence detection.

A simple and highly sensitive method for the determination of free and total (free + conjugated) catecholamines (norepinephrine, epinephrine and dopamine) in human urine is described which employs HPLC with fluorescence detection. Conjugated catecholamines (sulfate form) are hydrolyzed by a sulfatase-mediated reaction to the corresponding free amines. After cation exchange chromatography on a Toyopak IC-SP S cartridge, catecholamines and isoproterenol (internal standard) in urine samples were converted into the corresponding fluorescent compounds by reaction with 1,2-diphenylethylenediamine. These compounds were separated within 8 min on a reversed phase column with isocratic elution using a mixture of water, methanol and acetonitrile containing a Tris-hydrochloric acid buffer (pH 7.0). The detection limit for each catecholamine is ca 2 fmol per 100 microL injection volume.

High-performance liquid chromatographic determination of urinary catecholamines by pre-column solid-phase dansylation on alumina

Sensitive and selective high-performance liquid chromatographic determination of catecholamines by pre-column solid-phase dansylation is described. After catecholamines are adsorbed on alumina, the amino groups not responsible for adsorption are dansylated by a solid-phase reaction. The excess reagent and fluorescent contaminants are washed out, and the dansylated catecholamines are eluted and separated by reversed-phase high-performance liquid chromatography. The four catecholamine derivatives can be separated within 10 min and no major interfering peak is observed on chromatograms. The response of each catecholamine is linear from 10 to 500 pmol per sample and the detection limit is 0.5 pmol. This method was applied to determination of catecholamines in human urine.

親水性マトリックスを有する弱酸性イオン交換体を固定相に使用したヒト尿中カテコールアミンの分析

親水性マトリックスを有する弱酸性イオン交換体を固定相に使用したヒト尿中カテコールアミンの分析