Detection Of Taurine Research Articles

Identification of taurine biomarker in human biofluids using plasmonic patterns of silver nanostructure.

Taurine is now widely used as a new biomarker for cardiovascular and neurodegenerative diseases. This study discusses the importance of accurately determining taurine biomarker levels in various tissues and fluids for the early diagnosis of important pathologies and diseases. Current methods for taurine analysis face challenges such as low sensitivity, lack of selectivity, and complex procedures. Therefore, an efficient analytical method/technique is urgently needed by clinicians. A new paper-based photochemical method using triangular silver nanoparticles (TA-AgNPs) as optical nanoprobes was developed to detect taurine in human blood plasma and urine samples. This method involves a chemical reaction between taurine and TA-AgNPs, leading to a color change at pH 4.8, which is detected using a paper-based colorimetry (PCD) assay. The reaction is further confirmed by UV-visible spectrophotometry as the interaction between taurine and TA-AgNPs causes a significant change in the absorption spectrum, enabling the rapid and reliable measurement of this important biomarker with a detection limit of less than 0.2 μM to 20 mM. The method has been successfully applied to bioanalyzing taurine in human body fluids. Additionally, it requires optimized single-drop paper/parafilm-based colorimetric devices (OD-PCDs) for in situ and on-demand taurine analysis. This study represents the first use of TA-AgNPs for the specific and sensitive detection of taurine in real samples. The sensor design allows for the direct quantification of biomarkers in biological samples without the need for derivatization procedures or sample preparation. The simplicity and portability of OD-PCDs make them promising for tracking and monitoring. This method is expected to contribute to improving environmental health and occupational safety and represents a significant advancement in colorimetric analysis for the sensitive and selective detection of taurine, potentially providing a platform for the identification of taurine and other biomarkers.

Preparation of voltammetric sensors for taurine detection from Cu(II)-loaded carbon materials

ABSTRACT. In this study, for the detection of taurine in philological fluids, modified electrodes were prepared from glassy carbon electrodes with MWCNT (multi-wall carbon nanotube) + Cu(NO3)2 + carbon-based material. A carbon-based material was obtained by carbonization of Pinus sylvestris branch needles (CPS). Cu(NO3)2 and MWCNT structure (Cu(NO3)2/MWCNT) were added to the carbon-based material and the obtained mixture was used in the modification of the glassy carbon electrode surface. The surface morphology and structure of the prepared electrodes were characterized by electron microscopy scanning (SEM) and atomic force microscopy (AFM). Taurine detection with a modified electrode was made by cyclic voltammetry (CV) in 0.1 M KCl (vs. Ag/AgCl). The calibration curve of the modified electrode for taurine in the 10-150 µM range showed a linear response, and R2 value was 0.976. Limit of detection (LOD) and limit of quantification (LOQ) of the modified electrode were found 19 µM and 9.75 µM, respectively. The application of the electrode as a chemical sensor was carried out with commercially available energy drink samples. Satisfactory results have been obtained from the samples. The sensor can be used for routine taurine analysis. This electrode can quickly determine the amount of taurine in real samples with 90% accuracy in two minutes.
 KEY WORDS: Taurine detection, Modified electrode, MWCNT, Sensor, Cyclic voltammetry
 Bull. Chem. Soc. Ethiop. 2023, 37(6), 1565-1576. DOI: https://dx.doi.org/10.4314/bcse.v37i6.20

Poly-L-lysine functionalized graphene quantum dots embedded zirconium metal–organic framework-based fluorescence switch on-off-on nanoprobe for highly sensitive and selective detection of taurine

Taurine is now widely used as a novel diagnostic biomarker for cardiovascular disease. Unfortunately, engaged techniques for the analysis of taurine are suffering from low sensitivity, poor selectivity, and a tedious process. In this work, the poly-L-lysine functionalized graphene quantum dots embedded UiO-66@NH2 metal–organic framework (PLL-fGQDs@UiO-66@NH2 MOF) based turn ‘On-Off-On’ fluorescent nanoprobe was designed for taurine sensing. Initially, synthesized PLL-fGQDs, UiO-66@NH2 MOF, and PLL-fGQDs@UiO-66@NH2 MOF nanoprobe were confirmed using UV–Vis spectroscopy, FT-IR analysis, particle size analysis, fluorescence study, PXRD, SEM-EDAX, HR-TEM, etc. Here, anticipated PLL-fGQDs incorporation into UiO-66@NH2 MOF nanoprobe portrayed a highly fluorescent nanoprobe for taurine sensing. The copper (Cu2+) ions addition in the fluorescent nanoprobe resulted in fluorescence dampness followed by taurine addition showed the recovery of quenched fluorescence. Principally, it might be because of the greater binding affinity of Cu2+ ions towards taurine-containing oxygen atoms of a sulfonic group and the nitrogen atom of an amine group. The linear concentration range, limit of detection (LOD), and limit of quantification (LOQ) of taurine were found to be 5 ng/mL to 360 ng/mL, 2.91 ng/mL, and 8.84 ng/mL, respectively. It also provides a high selectivity towards taurine in the occurrence of interfering agents whereas practical applicability was assured by spiked artificial serum samples analysis. In conclusion, the designed PLL-fGQDs@UiO-66@NH2 MOF nanoprobe offers high sensitivity, selectivity, good stability, repeatability, and practicability. In the future, it can be used as a new nanoprobe for taurine recognition with improved performance than the traditional methods.

Making high salt concentrations for optimal chromatography compatible with electrospray ionization mass spectrometry using an ion exchange membrane suppressor: Analysis of biomarkers for transporter protein inhibition as a case study

This study reports on the potential of using ion-exchange suppressor technology in liquid chromatography—electrospray ionization mass spectrometry workflows. The aim was to use high salt concentrations to improve separation performance, while overcoming the resulting significant ion suppression during electrospray ionization. As a case study, we apply suppressor technology to the hydrophilic interaction liquid chromatography separation and detection of taurine and glycochenodeoxycholate sulfate, endogenous biomarkers for organic anion transporter protein inhibition. The desired chromatographic selectivity was achieved applying 100 mM ion-pairing agent, while competing ions negatively affecting MS sensitivity were actively removed post-column from the solvent via a charged partially permeable membrane and replaced with protons, resulting in an up to 10-fold increase in detection sensitivity.

Development of a method for simultaneous analysis of caffeine and taurine in energy drinks by micellar electrokinetic chromatography with diode-array detector

Abstract The objective of this study was to develop, optimize and validate a fast and reliable method for the simultaneous determination of caffeine and taurine contents by micellar electrokinetic chromatography with diode array detector, using direct and indirect detection concomitantly. Multivariate statistical techniques were used as a central composite design and the simultaneous optimization method of responses of Derringer and Suich were used for optimization. The method was applied in the analysis of 73 samples of energy drinks commercialized in Brazil. The optimized method employed a capillary tube with an extended bulb of 50 µm i.d. x 72 cm total length, an electrolyte containing 16.20 mmol.L-1 of benzoic acid and 39.90 mmol.L-1 of SDS, a pH value of 7.26, + 30 kV voltage, direct detection of caffeine at 274 nm and indirect detection of taurine at 230 nm. Validation parameters have demonstrated the reliability and applicability of this method. It was found that more than 50% of the samples were out of the legal limits determined by the Brazilian government regarding the taurine content and 68 % contained caffeine below the value declared on the label. Therefore, the need for greater control concerning the composition of these drinks exists.

A highly selective LSPR biosensor for the detection of taurine realized on optical fiber substrate and gold nanoparticles

Abstract In the current study, we report an enzyme based fiber optic biosensor utilizing the localized surface plasmon resonance (LSPR) of gold nanoparticles for the detection of taurine in the concentration range of 0–1 mM. For probe fabrication, gold nano-particles are decorated on an unclad portion of multimode optical fiber, and taurine dioxygenase enzyme is immobilized over them. The presence of taurine and its co-reactants alpha-ketoglutarate and oxygen in the vicinity of the probe activates the immobilized enzyme which elicits the chemical reaction that gets manifested in the form of refractive index change in the surrounding of gold nanoparticles. This changes the absorbance spectrum of the nanoparticles recorded at the output end of the fiber probe. The absorbance spectrum changes in terms of absorbance and peak absorbance wavelength. A change of 0.0115 in absorbance value is obtained for the change in taurine concentration from 0 to 1 mM. The limit of detection and the sensitivity of the sensor are found to be 53 µM and 0.0190 AU/mM, respectively. The sensor response is found to be stable and selective along with good repeatability. Being fabricated on optical fiber substrate, the sensor possesses the inherent advantages like online and remote monitoring of taurine along with immunity to electromagnetic noise. Moreover, the reported sensor has simple operation and is low in cost.

Enhanced electrochemiluminescence by ZnO nanowires for taurine determination

A novel electrochemiluminescence (ECL) sensor for the sensitive detection of taurine was developed. Taurine contains an aliphatic amine that gives it co-reactant properties. The ECL response of the taurine/[Ru(bpy)3]2+ system was analyzed on two different electrodes surfaces, screen-printed graphene and gold electrodes, before and after modification with ZnO nanowires (ZnO NWs). The ZnO NWs modified electrode yielded an enhanced ECL signal, allowing rapid detection of taurine at 5.5 × 10−6 mol L−1 detection limit. The ECL signal is stable and reproducible. The sensor has been applied to the determination of taurine in a commercial taurine supplement.

Electrochemical recognition of taurine biomarker in unprocessed human plasma samples using silver nanoparticlebased nanocomposite: A new platform for early stage diagnosis of neurodegenerative diseases of the nervous system.

The rapid and accurate determination of the level of taurine biomarker in various tissues and body fluids can be of great interest in the early diagnosis of several important pathologies and diseases. In the present study, an innovative electrochemical interface for quantitation of taurine based on ternary signal amplification strategy was fabricated. In this work, silver nanoparticles were electrodeposited onto green and biocompatible nanocomposite containing α-cyclodextrin as conductive matrix. Therefore, a double layer film based on α-cyclodextrin and silver nanoparticles was exploited to develop a highly sensitive electrochemical sensor for detection of taurine. Fully electrochemical methodology was used to prepare a transducer on a glassy carbon electrode which provided a high surface area towards sensitive detection of taurine biomarker. The surface morphology of electrode surface was characterized by high-resolution field emission scanning electron microscope (FE-SEM). The proposed sensing platform provides a simple tool for taurine detection. The calibration curve for taurine concentration was linear in 0.7nM to 0.1mM with low limit of quantification of 0.7nM. The practical analytical utility of the modified electrode was illustrated by determination of taurine in unprocessed human plasma samples with recovery of 90.8% to 104%.

Sensitive monitoring of taurine biomarker in unprocessed human plasma samples using a novel nanocomposite based on poly(aspartic acid) functionalized by graphene quantum dots.

The rapid and accurate determination of the level of taurine biomarker in various tissues and body fluids can be of great interest in the early diagnosis of several important pathologies and diseases. For the first time, this study reports on the electropolymerization of a low toxic and biocompatible nanocomposite "poly(aspartic acid)-graphene quantum dots (GQDs)" as a novel strategy for surface modification of glassy carbon electrode and preparation a new interface for measurement of taurine. Electrochemical deposition, as a well-controlled synthesis procedure, has been used for subsequently layer-by-layer preparation of GQDs nanostructures on poly(aspartic acid) using cyclic voltammetry techniques in the regime of -1.5 to 2V. The field emission scanning electron microscopy indicated immobilization of uniformly GQDs onto poly(aspartic acid) film. The modified electrode appeared as an effective electroactivity for detection of taurine biomarker using cyclic voltammetry, chronoamperometry, and differential pulse voltammetry. Enhancement of peak currents is ascribed to the fast heterogeneous electron transfer kinetics that arise from the synergistic coupling between the excellent properties of poly(aspartic acid) as semiconducting polymer, GQDs as high density of edge plane sites, and subtle electronic characteristics to chemical modification. Under the optimized analysis conditions, the prepared sensor for detection of taurine showed a low limit of quantification 0.001mM. Finally, the resulting prepared sensor allow the quantification of these biomarkers directly in biological samples without need of derivatization schemes or sample pretreatment.

Effects of eslicarbazepine acetate on acute and chronic latrunculin A-induced seizures and extracellular amino acid levels in the mouse hippocampus.

BackgroundLatrunculin A microperfusion of the hippocampus induces acute epileptic seizures and long-term biochemical changes leading to spontaneous seizures. This study tested the effect of eslicarbazepine acetate (ESL), a novel antiepileptic drug, on latrunculin A-induced acute and chronic seizures, and changes in brain amino acid extracellular levels. Hippocampi of Swiss mice were continuously perfused with a latrunculin A solution (4 μM, 1 μl/min, 7 h/day) with continuous EEG and videotape recording for 3 consecutive days. Microdialysate samples were analyzed by HPLC and fluorescence detection of taurine, glycine, aspartate, glutamate and GABA. Thereafter, mice were continuously video monitored for two months to identify chronic spontaneous seizures or behavioral changes. Control EEG recordings (8 h) were performed in all animals at least once a week for a minimum of one month.ResultsOral administration of ESL (100 mg/kg), previous to latrunculin A microperfusion, completely prevented acute latrunculin A-induced seizures as well as chronic seizures and all EEG chronic signs of paroxysmal activity. Hippocampal extracellular levels of taurine, glycine and aspartate were significantly increased during latrunculin A microperfusion, while GABA and glutamate levels remained unchanged. ESL reversed the increases in extracellular taurine, glycine and aspartate concentrations to basal levels and significantly reduced glutamate levels. Plasma and brain bioanalysis showed that ESL was completely metabolized within 1 h after administration to mainly eslicarbazepine, its major active metabolite.ConclusionESL treatment prevented acute latrunculin A-induced seizures as well as chronic seizures and all EEG chronic signs of paroxysmal activity, supporting a possible anti-epileptogenic effect of ESL in mice.

Spectrometric and Chromatographic Study of Reactive Oxidants Hypochlorous and Hypobromous Acids and Their Interactions with Taurine

In this study, we focused on the studying of taurine complexes with phenol and sodium hypochlorite, and of taurine with sodium hypobromite by spectrometry, reverse phase chromatography and ion-exchange chromatography. The formed complexes were studied under various conditions such as temperature (10, 20, 30, 40, 50 and 60 °C), and/or time of interaction (0, 5, 10, 15, 20, 25 and 30 min). In addition, we optimized high performance liquid chromatography coupled with UV detector for detection of taurine and its complexes with the acids. Taurine–phenol–hypochlorite complex was effectively separated under isocratic elution, mobile phase water:methanol 30:70 %, v:v, flow rate 1 mL min−1 and 55 °C. Taurine-bromamine complex was isolated under the following optimized conditions as isocratic elution, mobile phase water:methanol 85:15 % v:v, flow rate 1 mL min−1 and 55 °C. The limits of detection (3 S/N) were estimated as 1 μM for both types of complexes, i.e. for taurine. Further, we estimated recovery in one sample of urine (male 25 years), commercially achieved energy drink and tea leaves and varied from 79 to 86 %. Further, we aimed our attention at investigating the ability of the above characterized taurine and taurine complexes to scavenge reactive oxygen species. For this purpose, an ion-exchange liquid chromatography with post-column derivatization with ninhydrin and VIS detector was used. It clearly follows from the results obtained that taurine itself reacts with peroxide more intensely than in a bound form, which can be associated with the highest signal decrease. Complexes stabilized structure taurine against peroxide radicals, resulting in slower decreasing of peak heights. The most stable was taurine complexes with phenol and hypobromite.

Site-specific sampling of taurine from rat brain followed by on-line sample pre-concentration, throughout in-capillary derivatization and capillary electrophoresis

A method of pinpoint-sampling followed by on-line pre-concentration of the sample, throughout in-capillary derivatization and capillary electrophoretic separation was evaluated by demonstrating the detection of taurine, 2-aminoethanesulfonic acid at a specific location of a rat brain. The direct sampling of taurine from the rat brain was accomplished by using voltage injection associated with two kinds of driving forces, electrophoretic flow and electroosmotic flow (EOF). The capillary tube (75 microm of inner diameter x 375 microm of outer diameter) of the capillary electrophoresis (CE) apparatus was already filled with a CE run buffer, viz., 40 mM phosphate-borate buffer (pH 10) containing 2mM o-phthalaldehyde (OPA)/N-acetylcysteine (NAC) as the derivatization reagent. One end of a platinum wire (0.5mm o.d.), used as the anode, and the inlet end of capillary tube (from which a 1.0 cm long polyimide coating was removed), were pricked down onto the surface of either the cerebrum or cerebellum of a rat brain at a location of very small dimension. When a low voltage (5 kV, 30s) was applied, taurine began to move from the rat brain into the capillary tube, and, simultaneously, electric focusing of taurine occurred by the action of "the pH-junction effect" at the inlet end of the capillary tube. After completing the injection, both the platinum wire and capillary tube were detached from the brain and dipped into the run buffer in an anode reservoir filed with the same solution as that in the capillary tube for the CE apparatus. Then, by applying a high voltage (20 kV) between the ends of the capillary tube, taurine was automatically derivatized to yield the fluorescent derivative, separated and detected with fluorescence (E(x)=340 nm, E(m)=455 nm) during migration throughout the capillary tube. The migration profiles obtained from cerebrum and cerebellum appeared to be different, but the peak corresponding to taurine was identified on both electropherograms. The efficacy of the present method including sample on-line pre-concentration prior to throughout in-capillary derivatization CE was first verified with several preliminary experiments by using samples of taurine in water, saline and a piece of 1.5% agar-gel block, as an alternate standard for the rat brain used in this study.

Detection of taurine in biological tissues by (33)S NMR spectroscopy.

The potential of (33)S NMR spectroscopy for biochemical investigations on taurine (2-aminoethanesulfonic acid) is explored. It is demonstrated that (33)S NMR spectroscopy allows the selective and unequivocal identification of taurine in biological samples. (33)S NMR spectra of homogenated and intact tissues are reported for the first time, together with the spectrum of a living mollusc. Emphasis is placed on the importance of choosing appropriate signal processing methods to improve the quality of the (33)S NMR spectra of biological tissues.

A localized double-quantum filter for in vivo detection of taurine.

Noninvasive detection of taurine, an important amino acid involved in numerous physiological processes, by in vivo (1)H magnetic resonance (MR) spectroscopy is complicated by severe overlap of the taurine resonances with those of a number of other metabolites. Unambiguous differentiation of the taurine resonances requires spectral editing. In this study, the development of a localized spectral editing technique based on double-quantum filtering optimized for in vivo detection of taurine is described. The sequence recovers the taurine signal while substantially eliminating overlapping resonances and provides excellent three-dimensional spatial localization. The performance of the sequence is demonstrated both in phantoms and in rat brain in vivo. Magn Reson Med 42:454-460, 1999.

A localized double‐quantum filter for in vivo detection of taurine

A localized double‐quantum filter for in vivo detection of taurine

Determination of Taurine in Foods by HPLC with On-Column Fluorescence Derivatization

A simple and rapid method has been developed for the determination of taurine in foods by HPLC with an on-column fluorescence derivatization technique. Taurine was extracted from foods with water, and the crude extract was deproteinized with Carrez solution, followed by purification on a Bond Elut SCX cartridge column. Taurine was chromatographed on a polymer column with a mobile phase of acetonitrile and alkaline borate buffer solution containing o-phthaladehyde and 2-mercaptoethanol as derivatizing reagents. The average recoveries were greater than 90% for taurine added to various kinds of foods, such as milk products, shellfish, chicken egg and honey. Application of the method to the foods resulted in the detection of taurine in egg (1.26±0.15mg/100g) and honey (0.34±0.08mg/100g), in which taurine had not previously been found.

Immunological approach to the detection of taurine and immunocytochemical results.

An immunological approach to the detection of taurine resulted in antibodies specific enough to be used for immunocytochemical studies. The experimental conditions were similar to those previously described for raising antibodies against some small-sized neurotransmitter molecules: antisera were obtained from rabbits immunized with taurine conjugated to carrier proteins via glutaraldehyde and purified by adsorption on the glutaraldehyde-treated protein carriers. Antibody affinity and specificity were determined in competition experiments between conjugated taurine and other conjugated amino acids or derivatives by enzyme-linked immunosorbent assay. The resulting cross-reactivity ratios, calculated at half-displacement, showed conjugated taurine to be the best recognized compound. Given the molecular structure of taurine and the method used to prepare the conjugate, it seemed necessary to perform an oxidation step. However, adsorption of antisera on reoxidized or nonreoxidized taurine conjugates suggested that reoxidation did not make a significant difference. Immunocytochemical application of the sera revealed populations of strongly immunopositive nerve cells in the cerebellum, striatum, and septum. The results confirmed that antitaurine antibodies can be used as specific tools for a better understanding of the role of taurine in the central nervous system.

Simplified o-phtalaldehyde urea spray for the detection of taurine on thin-layer chromatographic plates

Simplified o-phtalaldehyde urea spray for the detection of taurine on thin-layer chromatographic plates

Spot test detection of taurine through demasking and pyrolytic effects

A test for taurine is described based on demasking of the inner-complex-bound sulfonic acid group by formaldehyde followed by pyrolysis reactions with mercury (II) cyanide or benzoin. The resulting hydrogen cyanide or sulfur dioxide can be detected in the gas phase by familiar color reactions. All the reactions may lie conducted within the limits of spot test analysis. Microchemical limits of identification are attained.