A Colorimetric Sensor for Dopamine Detection Based on Peroxidase-like Activity of Ce2(MoO4)3 Nanoplates

2019 ◽  
Vol 15 (3) ◽  
pp. 224-230 ◽  
Author(s):  
Mehdi Rahimi-Nasrabadi ◽  
Morteza Hosseini ◽  
Amir Homayoun Keihan ◽  
Mohammad Reza Ganjali
Keyword(s):  
High Performance ◽  
Limit Of Detection ◽  
Colorimetric Method ◽  
Hydroxyl Group ◽  
Blue Dye ◽  
Artificial Enzyme ◽  
One Pot ◽  
Dopamine Detection ◽  
Relative Standard ◽  
Peroxidase Mimics

Introduction: Artificial enzyme mimics are materials with similar catalytic function of natural enzymes. Among several types of artificial enzymes, nanomaterial-based products or nanozymes have been of particular interest to researchers. Materials and Methods: In this work, Ce2(MoO4)3 nanoplates were synthesized via a one-pot hydrothermal approach. SEM and EDS characterizations show a plated-like architecture with high purity. These nanoplates are shown to have an intrinsic peroxidase-mimetic activity. In the presence of H2O2, Ce2(MoO4)3 nanoplates could catalyse the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) with high performance to produce a blue dye (with an absorbance maximum at 652 nm). Dopamine (DA) has some reducibility due to the phenol hydroxyl group, which results in using H2O2 and causing the blue shallowing of the reaction solution by inhibiting the reaction between H2O2 and TMB. Based on that, a visual, sensitive and simple colorimetric method using Ce2(MoO4)3 nanoplates as peroxidase mimics was developed for detecting DA. Results and Conclusions: Suitable linear relationship for DA was obtained from 0.1 to 10 µM. The limit of detection (LOD) of the proposed method was calculated as 0.05 µM and the relative standard deviation (RSD) was less than 4.0%. The proposed method was successfully applied to DA detection in human serum sample.

Calcium/Copper alginate framework doped with CuO nano-particles as a novel adsorbent for micro-extraction of benzodiazepines from human serum

2020 ◽  
Vol 16 ◽  
Author(s):  
Nadereh Rahbar ◽  
Fatemeh Ahmadi ◽  
Zahra Ramezani ◽  
Masoumeh Nourani
Keyword(s):  
Human Serum ◽  
High Performance ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Nano Particles ◽  
Limit Of Quantification ◽  
Analytical Methodology ◽  
Fiber Fabrication ◽  
Relative Standard ◽  
Green Procedure

Background: Sample preparation is one of the most challenging phases in pharmaceutical analysis, especially in biological matrices, affecting the whole analytical methodology. Objective: In this study, a new Ca(II)/Cu(II)/alginate/CuO nanoparticles hydrogel fiber (CCACHF) was synthesized through a simple, green procedure and applied for fiber micro solid phase extraction (FMSPE) of diazepam (DIZ) and oxazepam (OXZ) as model drugs prior to high-performance liquid chromatography-UV detection (HPLC-UV). Methods: Composition and morphology of the prepared fiber were characterized and the effect of main parameters on the fiber fabrication and extraction efficiency have been studied and optimized. Results: In optimal conditions, calibration curves were linear ranging between 0.1–500 µg L−1 with regression coefficients of 0.9938 and 0.9968. Limit of detection (LOD) (S/N=3) and limit of quantification (LOQ) (S/N=10) of the technique for DIZ and OXZ were 0.03 to 0.1 µg L−1. Within-day and between-day relative standard deviations (RSDs) for DIZ and OXZ were 6.0–12.5% and 3.3–9.4%, respectively. Conclusion: The fabricated adsorbent has been substantially employed to extraction of selected benzo-diazepines (BZDs) from human serum real specimens and the obtained recoveries were also satisfactory (82.1-109.7%).

Rapid and Sensitive Liquid Chromatographic Method for Determination of Anastrozole in Different Polymer–Lipid Hybrid Nanoparticles

2021 ◽  
pp. 247263032098230
Author(s):  
Dilshad Ahmad ◽  
Faisal A. Al Meshaiti ◽  
Yazeed K. Al Anazi ◽  
Osama Al Owassil ◽  
Alaa Eldeen B. Yassin
Keyword(s):  
High Performance ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Hplc Method ◽  
Hybrid Nanoparticles ◽  
Array Detector ◽  
Relative Standard ◽  
Validation Parameters ◽  
Limit Of Quantitation ◽  
Inhibitor Drug

Anastrozole, an aromatase inhibitor drug, is used for the treatment of breast cancer in pre- and postmenopausal women. Anastrozole’s incorporation into nanoparticulate carriers would enhance its therapeutic performance. To perceive the exact loaded amount of drug in nanocarriers, a valid analytical method is required. The reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated by using the C18 column, 150 × 4.6 mm, 5 µm particle size, in isocratic mobile phase composed of 50:50 V/V (volume/volume) acetonitrile–phosphate buffer (pH 3) flowing at a rate of 1.0 mL/min, and a diode array detector (DAD) set at λmax = 215 nm. The validation parameters such as linearity, accuracy, specificity, precision, and robustness have proven the accuracy of the method, with the relative standard deviation percentage (% RSD) values < 2. The limit of detection of the method was found equal to 0.0150 µg/mL, and the limit of quantitation was 0.0607 µg/mL. The percent recovery of sample was in the range of 98.04–99.25%. The method has the advantage of being rapid with a drug retention time of 2.767 min, specific in terms of resolution of peaks void of interference with any of the excipients, and high reproducibility. This makes it highly applicable for quality control purposes.

scholarly journals SENSITIVE DETERMINATION OF RELATED SUBSTANCES IN PIOGLITAZONE HYDROCHLORIDE BY HPLC

2017 ◽  
Vol 9 (2) ◽  
pp. 34
Author(s):  
N. Balaji ◽  
Sayeeda Sultana
Keyword(s):  
Mobile Phase ◽  
High Performance ◽  
Limit Of Detection ◽  
High Performance Liquid Chromatographic ◽  
Hplc Method ◽  
Internal Diameter ◽  
Related Substances ◽  
Relative Standard ◽  
Limit Of Quantitation

Objective: An efficient, high performance liquid chromatographic method has been developed and validated for the quantification of related substances in pioglitazone hydrochloride drug substance.Methods: This method includes the determination of three related substances in pioglitazone hydrochloride. The mobile phase A is 0.1% w/v triethylamine in water with pH 2.5 adjusted by dilute phosphoric acid. The mobile phase B is premixed and degassed mixtures of acetonitrile and methanol. The flow rate was 1 ml/min. The elution used was gradient mode. The HPLC column used for the analysis was symmetry C18 with a length of 250 mm, the internal diameter of 4.6 mm and particle size of 5.0 microns.Results: The developed method was found to be linear with the range of 0.006-250% with a coefficient of correlation 0.99. The precision study revealed that the percentage relative standard deviation was within the acceptable limit. The limit of detection and limit of quantitation of the impurities was less than 0.002%and 0.006% with respect to pioglitazone hydrochloride test concentration of 2000 µg/ml respectively. This method has been validated as per ICH guidelines Q2 (R1).Conclusion: A reliable, economical HPLC method was magnificently established for quantitative analysis of related substances of pioglitazone hydrochloride drug substance.

scholarly journals Development and validation of reversed phase high performance liquid chromatography (RP-HPLC) for quantification of captopril in rabbit plasma

2020 ◽  
Author(s):  
Muhammad Fawad Rasool ◽  
Umbreen Fatima Qureshi ◽  
Nazar Muhammad Ranjha ◽  
Imran Imran ◽  
Mouqadus Un Nisa ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Mobile Phase ◽  
High Performance ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Rabbit Plasma ◽  
Rp Hplc ◽  
Relative Standard

AbstractTh accurate rapid, simple and selective reversed phase high performance liquid chromatography (RP-HPLC) has been established and validated for the determination of captopril (CAP). Chromatographic separation was accomplished using prepacked ODSI C18 column (250 mm × 4.6 mm with 5 μm particle size) in isocratic mode, with mobile phase consisting of water: acetonitrile (60:40 v/v), pH adjusted to 2.5 by using 85% orthophosphoric acid at a flow rate of 1 mL/min and UV detection was performed at 203 nm. RP-HPLC method used for the analysis of CAP in mobile phase and rabbit plasma was established and validated as per ICH-guidelines. It was carried out on a well-defined chromatographic peak of CAP was established with a retention time of 4.9 min and tailing factor of 1.871. The liquid–liquid extraction method was used for extraction of CAP from the plasma. Excellent linearity (R2 = 0.999) was shown over range 3.125–100 µg/mL with mean percentage recoveries ranges from 97 to 100.6%. Parameters of precision and accuracy of the developed method meet the established criteria. Intra and inter-day precision (% relative standard deviation) study was also performed which was less than 2% which indicate good reproducibility of the method. The limit of detection (LOD) and quantification for the CAP in plasma were 3.10 and 9.13 ng/mL respectively. The method was suitably validated and successfully applied to the determination of CAP in rabbit plasma samples.

METHOD DEVELOPMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF THYMOL AND EUGENOL BY USING RP-HPLC IN PURE AND IN EMULGEL FORMULATION

INDIAN DRUGS ◽  
2021 ◽  
Vol 58 (07) ◽  
pp. 59-65
Author(s):  
Vinita C. Patole ◽  
Shilpa P. Chaudhari ◽  
Keyword(s):  
High Performance ◽  
Method Development ◽  
Limit Of Detection ◽  
Hplc Method ◽  
Simultaneous Estimation ◽  
Limit Of Quantification ◽  
Relative Standard ◽  
Peak Areas ◽  
80 A 20 ◽  
Development And Validation

An attempt was made to develop a simple, selective, rapid and precise high-performance liquid chromatography (HPLC) method for simultaneous estimation of thymol and eugenol. Analysis was performed on a C18 column with the mobile phase consisting of solvent %A (water) and solvent %B (acetonitrile) with the following gradient: 0–1 min, 80 % A, 20 % B; 1–7 min, 40 % A and 60 % B; 7–12 min, 10 % A and 90 % B; and 12–15min, 80 % A and 20 % B at a flow rate of 0.6 mL/min. The compounds were well separated on a Thermo Scientific Hypersil BDS RP C18 column (4.6 mm × 150 mm, dp = 5 µm) and ultraviolet detection at 280 nm. The retention times of eugenol and thymol were 10.5 min and 11.6 min, respectively. Validation of the proposed method was carried out according to the guidelines of the International Council on Harmonization (ICH). The linearity of the method is good for thymol and eugenol over the concentration range of 1–50 ppm, and the r 2 values were 0.9996 for both thymol and eugenol. The calculated limit of detection (LOD) value was 0.5ppm and the limit of quantification (LOQ) value was 1ppm for both the analytes. The intra and interday relative standard deviation (RSD) of the retention time and peak areas was less than 3 %.The established method was appropriate, and the two markers were well resolved, enabling efficient quantitative analysis of thymol and eugenol.

Nanoparticulate Mycophenolic Acid Eye Drops - Analytical Validation of a High Performance Liquid Chromatography Assay and Stability Studies

2021 ◽  
Vol 09 ◽  
Author(s):  
Ali Al-Kulabi ◽  
Louis Gooden ◽  
Ijeoma F. Uchegbu
Keyword(s):  
Mycophenolic Acid ◽  
High Performance ◽  
Limit Of Detection ◽  
Immunosuppressive Agent ◽  
Plate Count ◽  
Eye Drops ◽  
Limit Of Quantification ◽  
Drug Content ◽  
Relative Standard ◽  
Validation Parameters

Background: Mycophenolic acid (MPA), an immunosuppressive agent, is used orally to reduce corneal graft rejection. However its oral use is associated with gastrointestinal side effects. Objectives: To prepare MPA nanoparticle eye drops and a validated analytical method. Methods: Aqueous MPA eye drops were prepared by nanoencapsulation of MPA using Nanomerics MET (N-palamitoylN-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan) at a MET, MPA ratio of 7.5: 1 g g-1 in the presence of glycerol (2.75% w/w). A validated MPA in-formulation drug substance assay was then developed. Results: MET-MPA formulations were prepared as well as a validated assay. Assay validation parameters for the analysis of MPA in the formulation were satisfactory [Plate count = 16458, Capacity Factor = 2.4, Tailing Factor = 1.02, linearity = 0.999 (0.016 – 0.5 mg mL-1 ), limit of detection = 0.056 mg mL-1 , limit of quantification = 0.17 mg mL-1 , accuracy = 98%, intraday and interday relative standard deviation = 0.45% and 4% respectively]. The candidate formulation (z - average mean = 66 ± 0.4 nm, polydispersity index = 0.12 ± 0.012, drug content = 1.14 ± 0.003 mg mL-1 , zeta potential = +8.5 ± 1.4 mV, pH = 7.4 ± 0.02, osmolarity = 309 ± 1.5 mOSm L-1 , viscosity = 1.04 ± 0.001 mPa.s) was then found to be stable for 14 days with respect to drug content at refrigeration, room and accelerated (40C )temperature and. All other formulation parameters were within the ocular comfort range. Conclusions: A validated assay (ICH and US FDA guidelines) for new MPA nanoparticle eye drops has been developed.

scholarly journals HPLC-DAD-ESI-MS Analysis for Simultaneous Quantitation of Phenolics in Taiwan Elderberry and Its Anti-Glycation Activity

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3861
Author(s):  
Ho-Shin Huang ◽  
Hsu-Sheng Yu ◽  
Chia-Hung Yen ◽  
Ean-Tun Liaw
Keyword(s):  
High Performance ◽  
Methanol Extract ◽  
Limit Of Detection ◽  
Total Phenolic ◽  
Photodiode Array Detection ◽  
Esi Ms ◽  
Relative Standard ◽  
Photodiode Array ◽  
Dpph Scavenging Activity ◽  
Dpph Scavenging

Sambucus formosana is most commonly used as a traditional herb medicine in Taiwan. In this study, high performance liquid chromatography equipped with photodiode array detection-mass (HPLC–DAD-ESI-MS) method was developed for the identification and quantification of bioactive phenolics. The developed method was also validated for accuracy, precision, limit of detection, and quantification. In this method, chlorogenic acid, rutin, isoquercetrin, nictoflorin, astragalin, and quercetin were quantified in linearity range of 10–100 (μg/mL) with a correlation coefficient of greater than 0.996. High recovery (86.5–93.1%) and good reproducibility were obtained for six phenolics with the relative standard deviation ranging from 1.7–3.1%. Therefore, the proposed method for simultaneous quantification of six bioactive phenolics in the extract and fractions of S. formosana using HPLC–DAD-ESI-MS detection under the optimized conditions is accurate and validated. Among the results, methanol extract showed the greatest values of total phenolic content (93.1 mg gallic acid equivalent/g). Additionally, the methanol extract revealed best antioxidant capacity based on the DPPH scavenging activity and anti-glycation activity (IC50 was observed at 97.1 and 77.9 μg/mL, respectively).

scholarly journals Determination of Tianeptine in Tablets by High-Performance Liquid Chromatography with Fluorescence Detection

2007 ◽  
Vol 90 (3) ◽  
pp. 720-724
Author(s):  
Sevgi Tatar Ulu
Keyword(s):  
Lower Limit ◽  
High Performance ◽  
Limit Of Detection ◽  
Internal Standard ◽  
Linear Calibration ◽  
Fluorescence Detector ◽  
Relative Standard ◽  
Validation Parameters ◽  
Limit Of Quantitation

Abstract A sensitive and selective high-performance liquid chromatographic method has been developed for the determination of tianeptine (Tia) in tablets. The method is based on derivatization of Tia with 4-chloro-7-nitrobenzofurazan (NBD-Cl). A mobile phase consisting of acetonitrile10 mM orthophosphoric acid (pH 2.5; 77 + 23) was used at a flow rate of 1 mL/min on a C18 column. The Tia-NBD derivative was monitored using a fluorescence detector, with emission set at 520 nm and excitation at 458 nm. Gabapentin was selected as an internal standard. Linear calibration graphs were obtained in the concentration range of 45300 ng/mL. The lower limit of detection (LOD) was 10 ng/mL at a signal-to-noise ratio of 4. The lower limit of quantitation (LOQ) was 45 ng/mL. The relative standard values for intra- and interday precision were &lt;0.46 and &lt;0.57%, respectively. The recovery of the drug samples ranged between 98.89 and 99.85%. No chromatographic interference from the tablet excipients was found. The proposed method was validated in terms of precision, robustness, recovery, LOD, and LOQ. All the validation parameters were within the acceptance range. The proposed method was applied for the determination of Tia in commercially available tablets. The results were compared with those obtained by an ultraviolet spectrophotometric method using t- and F-tests.

scholarly journals High-Performance Thin-Layer Chromatography with Densitometry for the Determination of Ciprofloxacin and Impurities in Drugs

2005 ◽  
Vol 88 (5) ◽  
pp. 1530-1536 ◽  
Author(s):  
Jan Krzek ◽  
Urszula Hubicka ◽  
Justyna Szczepańczyk
Keyword(s):  
Thin Layer ◽  
High Performance ◽  
Limit Of Detection ◽  
Degradation Products ◽  
Pharmaceutical Preparations ◽  
High Sensitivity ◽  
Good Precision ◽  
Relative Standard ◽  
Tlc Plates ◽  
Quantitative Analyses

Abstract A thin-layer chromatographic (TLC)-densitometric method has been developed for identification and quantification of ciprofloxacin (Rf = 0.61) and an ethylenediamine compound (Rf = 0.42), a desfluoro compound (Rf = 0.48), by-compound A (Rf = 0.53), and fluoroquinolonic acid (Rf = 0.68) as ciprofloxacin degradation products in pharmaceutical preparations. By using chloroform–methanol–25% ammonia (43 + 43 + 14, v/v/v) as the mobile phase and silica gel 60 F254 high-performance TLC plates as the stationary phase, it was possible to separate individual constituents that, when subjected to ultraviolet (UV) densitometric analysis at 330 nm for fluoroquinolonic acid and 277 nm for the other compounds, gave well developed peaks allowing easy qualitative and quantitative analyses. DMSO–methanol (1 + 1) was used to extract drug constituents. The method showed high sensitivity (limit of detection 10 to 44 ng), a wide linearity range (3 to 20 μg/mL), and good precision (2.32 to 6.46% relative standard deviation) and accuracy (percentage recoveries 98.62 to 101.52%) for individual constituents.

scholarly journals Quantitative Determination of Triterpenes from Amphiptherygium adstringens by Liquid Chromatography and Thin-Layer Chromatography and Morphological Analysis of Cuachalalate Preparations

2006 ◽  
Vol 89 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Andrés Navarrete ◽  
Bharathi Avula ◽  
Vaishali C Joshi ◽  
Xiuhong Ji ◽  
Paul Hersh ◽  
...  
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
High Performance ◽  
Limit Of Detection ◽  
Gastric Ulcers ◽  
Array Detector ◽  
Plant Materials ◽  
Relative Standard ◽  
Layer Chromatography

Abstract Amphiptherygium adstringens (Anacardiaceae/Julianaceae), local name cuachalalate, is used in folk medicine for the treatment of cholelithiasis, fevers, fresh wounds, hypercholesterolemia, gastritis, gastric ulcers, and cancer of the gastrointestinal tract. The development of column high-performance liquid chromatographyphotodiode array detector (LC-PDA) and high-performance thin-layer chromatography (HPTLC)densitometry methods for the determination of masticadienonic acid and 3-hydroxymasticadienonic acid in cuachalalate preparations is described in this paper. Good separation of the compounds could be achieved by both methods. Either might be preparable depending on the requirements. The LC separation was performed on a Phenomenex Synergi MAX-RP 80A reversed-phase column operated at 40C with detection at 215 nm. The plant materials were extracted with methanol by sonication. The triterpenes present in the plant material and commercial extracts were separated with an acetonitrilewater reagent alcohol isocratic system. The limit of detection was 0.10.2 g/mL. The relative standard deviation values for the determination of triterpenes in plant extracts were less than 1.00%. This is the first report of an analytical method developed for the quantitative analysis of triterpenes from Amphiptherygium adstringens by LC-PDA and HPTLC. The stem bark showed higher amounts of triterpenes, and low amounts in root and stem root. The microscopic description of the crude drug of cuachalalate was also provided.

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