Detection Of Riboflavin Research Articles

Trigger action of copper aminophosphate (X-CuAP) nanoparticles for enhanced electrochemical, photocatalyst and biological properties

The (en)-CuAP nanocrystals were synthesized by hydrothermal method. This material was designed rarely with it envelop good records in the characterization part, and morphologies also very clearly shown in the FE-SEM and HR-TEM analysis. The monoclinic phase of the (en)-CuAP nanocrystals functional groups was identified to the best coincide nature of the FT-IR and Raman spectroscopy studies. The obtained band gap energy is 2.65eV, which were lower than the other metal phosphate materials. Moreover, (en)-copper aminophosphate was tested to the electrochemical fabrication of the Phloroglucinol and Riboflavin, herewith phloroglucinol is an anodic peak and Riboflavin is better reduction peaks were appeared in the cyclic voltammetry studies. Hence, (en)-CuAP nanocrystals was electrochemically optimized both conditions, and its gives good transition at low concentrations. The modified electrodes have large surface area, high conductivity, and high catalytic activity of (en)-CuAP/GCE. The proposed sensors are high sensitivity for Phloroglucinol and Riboflavin detection and it was successfully developed with better performance of the electrochemical sensor. The (en)-CuAP nanocrystals have better reusability performance and enhanced to an excellent photocatalytic activities and antibacterial activities.

Advantages and drawbacks of the use of immobilized “green-synthesized” silver nanoparticles on gold nanolayer for near-field vibrational spectroscopic study of riboflavin

Nanoscopic near-field techniques are powerful tools in the chemical nanoanalysis thanks to their lateral resolution and the ability to detect trace amounts limiting to the single-molecule level and study molecular interactions at the same level. To achieve these goals, a gap mode is preferred, in which a large-scale plasmonic enhancing substrate with the adsorbed analyte is used and the Au/Ag scanning tip is approached to obtain high enhancement of the local electric field and form the hot–spot between the Au/Ag tip and the Au/Ag plasmonic surface. The appropriate enhancing substrate is crucial considering the enhancement factor and the optical response quality. This study focused on the riboflavin detection by tip-enhanced Raman scattering (TERS) and scanning near-field infrared microscopy (SNIM), immobilized Ag nanoparticles (NPs), synthesized by flavonoids reduction were employed. AgNPs immobilized on Au nanolayer via a dithiol-linker represent effective substrate exhibiting appropriate morphology and optical properties. SNIM provided insight into the intensity distribution of the riboflavin optical response. The optical amplitude and phase images indicate better adsorption of riboflavin on the AgNP-coated surface than on the Au-coated glass. TERS shows interferences of flavonoid residues on some substrates, but the riboflavin limit of detection was improved compared to surface-enhanced Raman scattering.

Electrochemical detection of riboflavin using tin-chitosan modified pencil graphite electrode

Abstract We here report a simple fabrication of tin incorporated chitosan polymer matrix coated pencil graphite electrode Sn/Cs/PGE for the electrochemical detection of riboflavin (RF). The tin incorporated chitosan polymer was prepared by mixing tin chloride in an aqueous acidic chitosan solution and the fabrication of Sn/Cs/PGE was done by simple immersion method for the first time. The surface characterization of the electrode sensor was carried out by Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and elemental mapping analysis. Electrochemical characterization was performed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) using 0.1 M KCl containing K3[Fe(CN)6]. These results revealed that the Sn/Cs/PGE shows a sensitive and fast electrocatalytic response towards the sensing of RF in physiological pH with a wide linear range (10 to 1200 nM) and low limit of detection (5.56 nM) compared to other electrodes. Moreover, the Sn/Cs/PGE possesses better stability with the anti-inference ability and the practical feasibility of the fabricated electrode shows satisfactory results towards the medicinal and food analysis.

Synthesis of homogeneously distributed gold nanoparticles built-in metal free organic framework: Electrochemical detection of riboflavin in pharmaceutical and human fluids samples

This study describes the synthesis of gold nanoparticles (AuNPs) incorporated melamine based covalent organic framework (MCOF) and their modification on glassy carbon electrode (GCE) for the sensitive and selective detection of riboflavin (RF). The MCOF was synthesized by refluxing melamine and terephthalaldehyde followed by AuNPs were incorporated into MCOF. The synthesized nanocomposite (MCOF-AuNPs) was confirmed by different spectral, microscopic and electrochemical methods. The TEM images show spherical AuNPs with an average diameter of 8 nm on the sheet-like structure of MCOF. The heterogeneous electron transfer rate constant (ket) was calculated for 1 mM K3/K4[Fe(CN)6] containing 0.1 M KCl at bare GC, MCOF and MCOF-AuNPs/GCEs was found to be 1.14, 1.72 and 4.31 × 10-4 cm2 s−1, respectively. The higher ket value achieved at MCOF-AuNPs/GCE indicates that the electron transfer rate reaction was faster at this electrode than others. The MCOF-AuNPs modified electrode was then utilized for the reduction of RF in 0.2 M phosphate-buffered saline (PBS) (pH 7.0). The MCOF-AuNPs/GCE showed 3.0 and 1.7-fold higher reduction current with 40 and 60 mV less positive potential shift against RF than bare GCE and MCOF/GCE. Under the optimized sensing parameters, the linear range concentration was achieved from 5 nM to 0.2 mM with the LOD of 2.0 nM. Finally, the present sensor was applied for the quantitative determination of RF in human biological fluids samples (human blood, urine, and saliva). Besides, the practical application was also demonstrated by determining RF in vitamin B-complex tablets and satisfactory results were obtained.

A high-performance voltammetric methodology for the ultra-sensitive detection of riboflavin in food matrices based on graphene oxide-covered hollow MnO2 spheres

A high-performance voltammetric methodology was developed to achieve ultra-sensitive detection of riboflavin, employing an electrode modified by graphene oxide-covered hollow MnO2 spheres nanocomposite with high catalytic activity, large surface area, and hierarchical layered structure. Under the optimal conditions, the current responses of the oxidation peak located at −0.39 V showed a good linear relationship versus the concentration of riboflavin in the range of 1.0 nM–4.0 μM in acetate buffer (pH 5.4). The limit of detection was determined as 0.26 nM. Moreover, the proposed electrode exhibited high reproducibility (relative standard deviation of 1.7%, n = 10) and excellent stability (97.6% sensitivity within two months), which has been successfully applied to the quantification of riboflavin in complicated food matrices, with results in good accordance with those obtained by chromatography as a reference method, indicating it is an effective sensing platform for ultra-sensitive determination of riboflavin in practical applications.

Electrochemical Fabrication of Poly (niacin) Modified Graphite Paste Electrode and its Application for the Detection of Riboflavin

Objective:A poly niacin (NN) modified graphite paste electrode was prepared through a simple electrochemical polymerization route for the determination of Riboflavin (RF)Methods:Electropolymerization technique was used for the preparation of a modified electrode. The electrochemical impedance spectroscopy (EIS) method was used to study the surface behaviors and conductivity of the bare and modified electrodes. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were used to study the electrochemical behavior of RF using 0.2 M PBS of 7.5 pH.Results:Poly niacin modified graphite paste electrode (PNNMGPE) provides more affinity towards RF detection with high sensitivity and selectivity over bare graphite paste electrode. RF calibration curve was obtained by LSV between 5.0 µM to 65.0 µM with 0.782 µM limit of detection (LOD) and 2.7608 µM limit of quantification (LOQ), respectively. Selective analysis of RF in the presence of ascorbic acid (AA) and dopamine (DA) was performed at PNNMGPE by the LSV method.Conclusion:The developed PNNMGPE was tested for RF analysis in a multivitamin tablet with good results. Furthermore, the developed electrode shows good stability and reproducibility.

Binary Metal Oxide Adsorbed Graphene Modified Glassy Carbon Electrode for Detection of Riboflavin

AbstractTungsten oxide (W) decorated titanium oxide (T) adsorbed onto a graphene (Gr) and modified the glassy carbon electrode for the electrochemical quantification of riboflavin (RF) in edible food and pharmaceuticals. For comparison, nanocomposites are formed using graphene oxide (GO), reduced graphene oxide (rGO) and pure graphite (G) sheets to study the electrochemical activities towards riboflavin. The ternary WTGr modified GCE shows the highest electrocatalytic activity due to synergetic interactions between the metal oxide and graphene. The electrochemical observations are supported by the SEM, HRTEM, XRD, UV‐Vis, Zeta potential (ζ) and size data. The sensor shows a wide linear range 20 nM–2.5 μM with a detection limit 25.24 nM and sensitivity (4.249×10−8 A/nM). The fabricated sensor is validated in real samples.

Fabrication of Poly (Evans Blue) Modified Graphite Paste Electrode as an Electrochemical sensor for Sensitive and Instant Riboflavin Detection

Electro-analysis of Riboflavin (RN) consumed as vitamin has been delved by constructing the poly (Evans Blue) modified graphite paste electrode (PEBMGPE) as an electrochemical detector. Voltammetric determination of RN in 0.2 M PBS (pH 7.0) at the electro-active layer of the PEBMGPE was conducted. The PEBMGPE plays a crucial role as sensing tool towards the detection of RN compared to the BGPE. The topographical features of the bare graphite paste electrode (BGPE) and PEBMGPE was acquired by the FESEM surface analysis. All experimental factors such as applied potential, the effect of scan rate, impact of the pH were optimized. Employing the Differential pulse voltammetry (DPV) approaches using the good experimental circumstances the analytical curve was linear in the range of 6×10 -6 -1.5×10 -4 M, the detection limit and limit of quantification gained as 2.1×10 -7 M and 7.1×10-7 M, respectively. Subsequently, good repeatability, excellent reproducibility, and adequate stability, high sensitivity were achieved for the PEBMGPE sensor. In addition, the PEBMGPE sensor was applied for the interference study of RN with Dopamine (DA) and Paracetamol (PR). Besides the practicability of the projected sensor was successfully utilized for the detection of the RN in the pharmaceutical formulations

A ratiometric fluorescent sensor based on g-CNQDs@Zn-MOF for the sensitive detection of riboflavin via FRET.

A novel ratiometric fluorescent sensor based on Förster resonance energy transfer (FRET) platform was designed for riboflavin (RF) detection. The graphitic carbon nitrides quantum dots - Zn-MOF composite (g-CNQDs@Zn-MOF) was used as the fluorescent probe. In the FRET system, g-CNQDs@Zn-MOF and RF acted as donor and acceptor, respectively. The probe exhibited high sensitivity and good selectivity to RF, and had been successfully used for the detection of RF in milk and vitamin B2 tablets. The detection limit of the sensor was 15nM. The strategy expanded the application of MOF in sensing filed and provided a new method for the detection of RF.

Fluorescence resonance energy transfer from pyrene nanoparticles to riboflavin: Spectroscopic insights and analytical application

The aqueous suspension of fluorescent pyrene nanoparticles (PyNPs) were prepared by a reprecipitation method in the presence of sodium dodecyl sulphate (SDS) as a stabilizer. The PyNPs shows bathochromically shifted aggregation induced enhanced emission (AIEE) in the spectral region 400 nm to 600 nm peaking at 466 nm where Riboflavin (RF) absorbs strongly. The systematic FRET experiments performed by measuring fluorescence quenching of PyNPs with successive addition of RF analyte exploited the use of PyNPs as nano probe for detection of RF in aqueous solution with lower limit of detection 10.163 × 10 -5 mol.L -1 . The fluorescence of PyNPs was quenched by RF and quenching is in accordance with the Stern-Volmer relation. The distance r between the donor (PyNPs) and acceptor (RF) molecules was obtained according to the fluorescence resonance energy transfer. The evaluation of photo kinetic and thermodynamic parameters such as quenching rate constant (k q ), enthalpy change (ΔH), Gibbs free energy change (ΔG) and entropy change (ΔS) was calculated by quenching results obtained at different constant temperatures. The proposed FRET method based on fluorescence quenching of PyNPs was used further to develop an analytical relation for estimation of RF from pharmaceutical samples available commercially in the market.

Microfibers of Embellished Cobalt—Zeolite Imidazole Framework for Vitamin—B2 Detection

Cobalt—Zeolite Imidazole Framework (Co-ZIF) microfibers are synthesized by electrospinning method used for the quantification of Riboflavin (RF). Cobalt ions are tethered uniformly along the surface of the ZIF by electrostatic attraction. Crystalline cobalt ions are interconnected with ZIFs, which makes strongly bonded tetrahedral structure of Co-ZIF providing the improved stability in the composite. The cyclic voltammetric profile reveals , excellent catalytic behavior of the electrodes and the linear plot evidences for interfacial electron transfer of RF to Co-ZIF microfiber modified GCE surface. Interestingly, a selective determination of RF with the linear range of 100 nM to 1 mM with the low limit detection of 81 nM by square wave voltammetry (SWV) technique is demonstrated. The developed RF sensor shows anti-interference ability towards other electroactive species and it has been successfully employed toward the real sample for the detection of RF with good recovery result.

Effective electrochemical detection of riboflavin and butylated hydroxy anisole based on azure A and nickel hexacyanoferrate framework on graphite electrode

A highly stable and layered combination of Azure A (AZA) and Nickel hexacyanoferrate (NiHCF) grafted on graphite electrode was used as selective sensor for the determination of Riboflavin and Butylated hydroxy anisole. The surface of modified electrode was analysed and confirmed by scanning electron microscopy, EDS and Confocal Raman spectroscopy studies. Cyclic voltammetry analysis exhibited redox peaks for NiHCF in NaNO3 solution (0.1 M) and AZA in PBS solution (0.1 M) with formal potential as 0.32 V and -0.39 V at a scan rate 50 mV/s. The AZA/NiHCF modified electrode exhibited remarkable electrocatalytic performance for BHA oxidation by the NiHCF system and reduction of RF by AZA system with the detection limit as 2.22 × 10−6 M and 1.45 × 10−6 M respectively. The sensitivity was calculated as 0.1234 µA/µM for BHA and as 0.1352 µA/µM for RF. Finally, the proposed sensor was applied to estimate BHA in biscuit and RF in pharmaceutical samples successfully.

A simple and low-cost poly (dl-phenylalanine) modified carbon sensor for the improved electrochemical analysis of Riboflavin

The current study reports on the electroanalysis of Riboflavin (RF) on the surface of a poly dl -phenylalanine modified carbon paste sensor (PDLPAMCPS). The developed sensor caused a noticeable electrocatalytic action for the redox activity of RF in a phosphate buffer solution (PBS) of pH 6.5. This analysis was evaluated using differential pulse voltammetry (DPV) and cyclic voltammetry (CV) techniques. The active surface of the functioning sensor exposes well developed anodic peak with prominent electron transfer. PDLPAMCPS shows distinctive and improved DPV and CV peaks for RF with and without the presence of organic dyes and dopamine (DA). The impact of the solution pH, scan rate, accumulation potential and concentration on RF at PDLPAMCPS were studied. A vibrant linear growth was observed between the oxidation peak current and the RF concentration in the range of 6.0 μM–30.0 μM, which provides a lower limit of detection (LOD) of 92 nM with excellent sensitivity. The proposed method and sensor were applied for the assessment of RF in medicine sample as an analytical application with fine recoveries and low LOD. • A simple and low-cost carbon sensor was designed using poly ( dl -Phenylalanine) for the sensing of Riboflavin. • Prepared sensor was characterized by CV, DPV, EIS and FE-SEM analysis. • Equipped sensor shows high sensitivity, selectivity and lower LOD of 92 nM towards Riboflavin detection. • Interference effect on prepared sensor for Riboflavin was studied.

SnO2 nanowires for Electrochemical Detection of Riboflavin

Introduction There are few selected nanomaterials that are being used as base materials in emerging technologies for possessing exceptional potential. Among such materials, tin oxide (SnO2) is a material with exciting sensing properties such as high sensitivity, good chemical stability, high electron mobility, fast response, and good recovery speed [1]. Electrochemical analysis using SnO2 nanomaterial has been used for the qualitative and quantitative determination of amount of electro active analytes. This method is reported to be highly accurate, reliable and cheap. Several characterization techniques are used to investigate the electrochemical response like Cyclic voltammetry (CV), Differential Pulse Voltammetry (DPV), Square Wave Voltammetry (SWV) or Pulsed Amperiometry (PA) [2]. SnO2 nanowires are hereby reported for the detection of Riboflavin (RF). It is observed that the synthesized nanowires can detect the analyte efficiently. Method SnO2 nanowires were synthesized by template-directed electrodeposition. Copper foil was used as the substrate. The Sn nanowires were electrodeposited into the nanoholes of the polycarbonate membranes by a three-electrode system in a solution containing 0.05 M SnCl2.2H2O and HCl at room temperature. The electrochemical synthesis was performed on a CHI660 electrochemical Workstation. The electrodeposition was performed at -0.7 V (vs saturated Ag/AgCl), with platinum serving as the counter electrode. After SnO2 nanowires were electrodeposited into track etch polycarbonate membranes, the assembly system was annealed in the air at 85oC to form an ordered SnO2 nanowire array. Ag/AgCl as a reference electrode and gold as an auxillary electrode were used to set up the modifications in detection technique. CV, DPV and EIS techniques were used for the successful detection of RF. Moreover, for measuring the pH values, a pH meter with a combined electrode (glass-reference electrode) was used. All potentials are measured against the Ag/AgCl reference electrode at room temperature. Results and Conclusions Field-emission scanning electron microscopy (FE-SEM) is used to characterize the morphologies of the as-prepared products. To demonstrate the chemical composition, EDS analysis was performed. The crystal structure of the as-prepared samples is determined by X-ray diffraction (XRD) with Cu Kα radiation. All these results showed that the nanowires are successfully synthesized in their pure form. Electrochemical studies were carried out by CV and DPV studies. EIS technique also verified about the successful determination of analytes. The developed sensor exhibits good stability, reproducibility and efficiency. Moreover, its practical application was also checked in pharmaceutical samples by the recovery test. For RF content in pharmaceutical samples in the range from 52-150 μM, the developed sensor retains its linearity which indicates that the fabricated sensor not only works well in 0-13 μM range but beyond that range also. Compared with all other existing electrodes reported in the literature, the reported work not only showed remarkably lower detection limit but also the cheapest electrode ever synthesized.

Synthesis of SnO2 nanowires as a reusable and flexible electrode for electrochemical detection of riboflavin

The fabrication and testing of a riboflavin (RF) sensor based on the use of tin oxide (SnO2) nanowires was successfully attained. Template directed electrodeposition was used to produce one-dimensional nanostructures of SnO2. SnO2 nanowires were achieved by the electrodeposition of tin(ii) chloride into the nanochannels of the porous polycarbonate membrane by applying potential of −0.75 V. Various techniques such as XRD, FESEM, EDS and FTIR were used to characterize the synthesized nanowires. All electrochemical studies were carried out in phosphate buffer pH 7.0 and 0.1 Vs−1 scan rate. The fabricated sensor showed excellent anti-interference ability against electroactive species and metal ions. It also proved its long-term stability and good reproducibility with RSD values 1.90% and 1.30% respectively. The voltammetric signal increases linearly in the 0–13 μM concentrations range with a lower detection limit of 0.6 µM. Rs and Rct values decreased significantly with increasing concentration. The synthesized electrode is proved to be useful for the estimation of the RF content in pharmaceutical samples with 98% recovery.

Green-Synthesized Rice-Shaped Copper Oxide Nanoparticles Using Caesalpinia bonducella Seed Extract and Their Applications.

Copper oxide nanoparticles (CuO Nps) were synthesized using Caesalpinia bonducella seed extract via a green synthetic pathway and were evaluated for electrocatalytic properties by carrying out electrochemical detection of riboflavin [vitamin B2 (VB2)]. The seeds of C. bonducella are known to have strong antioxidant properties arising due to the presence of various components, including citrulline, phytosterinin, β-carotene, and flavonoids, which serve as reducing, stabilizing, and capping agents. The synthesized CuO Nps were characterized using UV–visible spectroscopy, Fourier transform infrared spectroscopy, thermogravimetrc analysis–differential thermal analysis, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy and further used as a modifier for a graphite electrode surface. The modified electrode was electrochemically characterized by cyclic voltammetry, square-wave voltammetry, and chronoamperometry techniques and then assessed for electrocatalysis by carrying out the detection of VB2. The electrochemical sensor could be used for nanomolar detection of VB2 with an observed linear range of 3.13–56.3 nM with a limit of detection of 1.04 nM. The electrode showed good stability and reproducibility over a period of 120 days. The CuO Nps were further analyzed for antibacterial effect with Gram-positive and Gram-negative bacteria, and in both cases, high antibacterial activity was clearly observed. The newly synthesized nanoparticles, thus, proved to be an interesting material for electrochemical and biological studies.

Application of modifier-free gold nanoparticle colorimetric sensing for rapid screening and detection of vitamin B1

A simple and fast alternative colorimetric sensing platform for selective determination of vitamin B1 in urine samples was proposed.

Application of TiO2 Nanoparticles Modified Carbon Paste Electrode for the Determination of Vitamin B2

In the present work, a modified carbon paste electrode was fabricated by grinding the mixture of graphite powder and paraffin oil (as a binder) with a sufficient amount of TiO2 nanoparticles. The electrochemical behavior of vitamin B2 (riboflavin) was investigated on the surface of the electrode using cyclic voltammetry and differential pulse voltammetry (DPV). The results showed that the electrochemical response of riboflavin was improved considerably at the modified electrode comparing to the unmodified electrode. Effects of TiO2 percentage, pH value, pulse time, and pulse amplitude were optimized using DPV technique. Under the optimized conditions, a linear dynamic range of 2.4 × 10–6 to 2.4 × 10–4 M with the detection limit of 1.6 × 10–6 M for vitamin B2 was obtained. The effects of some common interferences were examined, and the method was successfully employed to the detection of riboflavin in pharmaceutical formulations.

Sensitive monitoring of riboflavin in commercial multivitamins using poly (chitosan)-based nanocomposite.

The rapid and sensitive determination of riboflavin (RF) is important for the treatment of seborrheic and glossitis dermatitis, sunlight sensitivity, mucosal, and skin disorders. In this work, an electrochemical sensor was developed by electrodes modification using poly (chitosan) to sensitive detection of RF in commercial multivitamin. Electrodeposition of chitosan on the surface of glass carbon electrode was performed using cyclic voltammetry technique in the range of -1 to +1 V. The modified electrode surface morphology was characterized using a high-resolution field emission scanning electron microscope. The modified electrode was used as an effective electrical interface for the detection of RF using cyclic, differential pulse, and square wave voltammetry techniques. Finally, the sensor was applied to determine RF in commercial multivitamins. In optimum conditions, the linear range for the standard sample of RF and commercial multivitamins 94 to 333μM and 24.6 to 176μM were obtained, respectively. Low limit of quantification (LLOQ) were obtained as 24.6μM.

Fluorophotometric Determination of Riboflavin Concentrations in a Human Artificial Anterior Chamber Model.

PurposeCorneal cross-linking (CXL) requires an adequate corneal riboflavin impregnation, which is clinically assessed by verification of a riboflavin “flare” in the anterior chamber. We set out to replace this subjective assessment with an objective measurement method and evaluated fluorophotometry as an apparatus-based technique for riboflavin detection in the anterior chamber.MethodsIn an artificial anterior chamber model using human corneas and a modified Fluorotron fluorophotometer, we determined the detection limits of riboflavin concentrations across native corneas by comparison measurements of the same concentrations in glass cuvettes. Subsequently, standard CXL procedures with corneal application of riboflavin were simulated and the proportions of riboflavin entering the anterior chamber were measured fluorophotometrically.ResultsThe measurement results of the riboflavin dilution series in the artificial anterior chamber showed a very high concordance with the results obtained in a glass cuvette (Pitman test P = 0.329). In the CXL simulation, the mean riboflavin concentration measured in the anterior chamber increased within 15 minutes from 5 (±1) to 903 (±204) ng/mL and stood at 1089 (±56) ng/mL after 30 minutes.ConclusionsFluorophotometry is able to measure riboflavin in an artificial anterior chamber across human corneas over a wide range of concentrations and it reliably detects the increasing riboflavin signal in simulated CXL procedures.Translational RelevanceThe replacement of the subjective riboflavin detection by a technically straightforward, objective detection method might increase patient safety and treatment efficiency in CXL.