A novel solid-phase extraction-spectrofluorimetric method for the direct determination of atenolol in human urine: A novel spectrofluoimetriv method for the determination of atenolol

Eco-friendly simultaneous estimation of atenolol and losartan potassium in spiked human plasma via synchronous fluorescence with sustainability assessment

A green, sensitive, and fast spectrofluorimetric technique for the simultaneous determination of atenolol (ATN) and losartan potassium (LSR) was developed. The proposed technique relied on the implementation of a first derivative synchronous fluorescence spectroscopy for the determination of the investigated drugs simultaneously without pretreatment procedures. The synchronous fluorescence of both drugs was measured in methanol at Δλ of 100 nm, and the first derivative peak amplitudes (1D) were measured at 321 nm for ATN and 348 nm for LSR, each at the zero-crossing point of the other. The method was rectilinear over the concentration ranges of 100-1000 ng/mL and 50-500 ng/mL for ATN and LSR, respectively. The proposed technique was successfully applied for the determination of the studied drugs in their laboratory-prepared mixture and pharmaceutical formulations, demonstrating high mean recoveries of 100.54% for ATN and 100.62% for LSR, without interference from common excipients. The results were in good agreement with those obtained by the comparison method. Three recent greenness assessment tools, the Eco-Scale tool, the Green Analytical Procedure Index (GAPI) metric, and the Analytical GREEnness metric approach, were employed to affirm the greenness of the proposed method. The developed method was proven to be eco-friendly.

Derivatization-free conventional and synchronous spectrofluorimetric estimation of atenolol and amlodipine

Fixed-dose combinations for treatment of hypertension are observed in many dosages in the global market because of their high efficacy compared to single component dosage forms. One of these effective combinations is atenolol/amlodipine which is usually administered to patients with hypertension. Hence, development of facile, accurate, and sensitive methods for simultaneous estimation of atenolol and amlodipine is of great importance for quality control testing and pharmacokinetic studies. In our study, we developed two spectrofluorimetric methods to estimate both compounds in different pharmaceuticals. The first method is based on the estimation of atenolol and amlodipine by double-scan conventional spectrofluorimetry where the fluorescence intensities of atenolol and amlodipine were measured at 299 and 434 nm after excitation at 274 and 358 nm, respectively. The second method depends on synchronous spectrofluorimetric measurements at Δλ = 70 nm, where atenolol is assayed at 266 nm and amlodipine is assayed at 363 nm. Methods' optimizations were carried out to select the optimum conditions that render high selectivity and sensitivity. Such optimizations included assessment of solvents, surfactants, buffer volumes and pHs. The conventional spectrofluorimetric method was rectilinear over concentration range of 30.0-300.0 ng mL-1 for atenolol and 0.25-7.00 µg mL-1 for amlodipine while the synchronous spectrofluorimetric method showed linearity over the ranges of 0.60-6.00 µg mL-1 for atenolol and 0.25-7.00 µg mL-1 for amlodipine with low detection limits (≤0.12 µg mL-1) for both compounds in the two methods. It is the first work that demonstrates estimation of atenolol and amlodipine in their combinations by conventional and synchronous spectrofluorimetry. Both methods were applied to estimate atenolol and amlodipine in different pharmaceuticals with high %recovery and low %RSD.

Label-free green estimation of atenolol and ivabradine hydrochloride in pharmaceutical and biological matrices by synchronous spectrofluorimetry

In this work, a label-free, rapid, and sensitive synchronous spectrofluorometric method was implemented to assay atenolol (ATL) and ivabradine hydrochloride (IVB) in pharmaceutical and biological matrices. Simultaneous determination of ATL and IVB by conventional spectrofluorometry cannot be implemented because of the clear overlap of the emmision spectra of ATL and IVB. To overcome this problem, synchronous fluorescence measurements at a constant wavelength difference (Δλ) combined with mathematical derivatization of the zero order spectra were perforemed. The results indicated a good resolution between emission spectra of the studied drugs when the first-order derivative of the synchronous fluorescence scans at Δλ = 40 nm was conducted using ethanol as the optimum solvent which is less hazardous than other organic solvents such as methanol and acetonitrile, keeping the method safe and green. The amplitudes of the first derivative synchronous fluorescent scans of ATL and IVB in ethanol were monitored at 286 and 270 nm to simultaneously estimate ATL and IVB, respectively. Method optimisation was conducted by assessing different solvents, buffer pHs, and surfactants. The optimum results were obtained when ethanol was utilized as a solvent without using any other additives. The developed method was linear over concentration ranges of 10.0-250.0 ng mL^-1 for IVB and 100.0-800.0 ng mL^-1 for ATL with detection limits of 3.07 and 26.49 ng mL^-1 for IVB and ATL, respectively. The method was utilized to assay the studied drugs in their dosages and in human urine samples with acceptable % recoveries and RSD values. The greenness of the method was implemented by three approaches involving the recently reported metric (AGREE) which ensured the eco-freindship and safety of the method.

Sensitive Derivative Synchronous and Micellar Enhanced Ecofriendly Spectrofluorimetric Methods for the Determination of Atenolol, Diclofenac, and Triclosan in Drinking Tap Water

BACKGROUND

Nowadays, emergence of unexpected contaminants in drinking water is a challenging environmental problem facing humanity.

OBJECTIVE

Two eco-friendly spectrofluorimetric methods were proposed for the determination of three unexpected contaminants in drinking tap water.

METHODS

The first method is first derivative synchronous spectrofluorimetric method which was developed for simultaneous determination of atenolol (ATN) and diclofenac (DCF) without prior separation at Δλ = 70 nm and at Δλ = 80 nm for ATN and DCF, respectively. The second method was based on using sodium dodecyl sulfate (SDS) as fluorescent enhancer of triclosan (TCS) native fluorescence. TCS exhibits enhanced fluorescence at λ emission = 600 nm upon excitation at λ excitation = 299.4 nm. Solid phase extraction was carried out in both methods.

RESULTS

Linear calibration curves were obtained in concentration range of (4-3000 ng/mL) for ATN and (4-2000 ng/mL) for DCF, by measuring first derivative signal of fluorescence at 300 nm and 375.2 nm, respectively. TCS exhibits linear range (0.1-1 ng/mL) at 600 nm. Mean percentage recoveries were 101.04 ± 0.571, 99.66 ± 1.443, and 99.73 ± 0.566 for ATN, DCF, and TCS, respectively.

CONCLUSIONS

Validation of both methods were performed according to the International Conference on Harmonization guidelines. Results obtained were statistically compared with published methods and no significant differences were found. The proposed methods' greenness is evaluated using analytical Eco-scale and Green Analytical Procedure Index. A greenness comparison with previously published methods has been performed.

HIGHLIGHTS

Both methods were found to be eco-friendly and were successfully applied for the determination of the emerging contaminants in drinking tap water.

Molecularly Imprinted Solid-Phase Extraction Sorbents for the Selective Extraction of Drugs from Human Urine

Development of molecularly imprinted solid-phase extraction (MISPE) sorbents for the removal of drugs from human urine is described. MISPE sorbents are synthesized through free radical polymerization mechanism and non-covalent imprinting approach. After the completion of the polymerization, bulk polymer is ground using an analytical mill and then wet-sieved. Later on, MISPE sorbent has been dry-packed into solid-phase extraction cartridges after the extraction of template drug molecule. Eluates from the cartridges are analyzed using a spectrophotometer or spectrofluorimeter for the determination of target analyte by referring to the calibration curves.

A Versatile Stability-indicating Liquid Chromatographic Method for the Simultaneous Determination of Atenolol, Hydrochlorothiazide and Chlorthalidone

Background:

Atenolol is a selective beta 1 blocker that can be used alone or in combination with hydrochlorothiazide or with chlorthalidone for the treatment of hypertension and prevention from a heart attack.

Objective:

The main target of this work was to improve modern, easy, accurate and selective liquid chromatographic method (RP-HPLC) for the determination of these drugs in the presence of their degradation products. These methods can be used as analytical gadgets in quality control laboratories for a routine examination.

Methods:

In this method, the separation was accomplished through an Inertsil® ODS-3V C18 column (250 mm x 4.6 mm, 5 μm), the mobile phase used was 25 mM aqueous potassium dihydrogen orthophosphate solution adjusted to pH 6.8 by using 0.1M sodium hydroxide and acetonitrile (77 : 23, v/v), the flow rate used was 1 ml/min and detection was achieved at 235 nm using UV.

Results:

All peaks were sharp and well separated, the retention times were atenolol degradation (ATN Deg.) 2.311 min, atenolol (ATN) 2.580 min, hydrochlorothiazide degradation (HCT Deg.) 5.890 min, hydrochlorothiazide (HCT) 7.016 min, chlorthalidone degradation CTD Deg 8.018 min and chlorthalidone (CTD) 14.972 min. Linearity was obtained and the range of concentrations was 20- 160 μg/ml for atenolol, 10-80 μg/ml for hydrochlorothiazide and 10-80 μg/ml for chlorthalidone. According to ICH guidelines, method validation was accomplished, these methods include linearity, accuracy, selectivity, precision and robustness.

Conclusion:

The optimized method demonstrated to be specific, robust and accurate for the quality control of the cited drugs in pharmaceutical dosage forms.

Synthesis and Characterisation of a Monolithic Imprinted Column Using a Methacrylic Acid Monomer with Porogen Propanol for Atenolol Analysis

A monolithic imprinted atenolol column was constructed by in situ polymerisation using a methacrylic acid monomer and a 1 : 1 (v/v) porogen of propanol: toluene with two template: monomer: crosslinker combinations, namely, MIP 1 (1 : 4 : 20) and MIP 2 (1 : 5 : 20). Physical characterisation of the monolithic columns consisted of permeability testing, Fourier transform infrared (FTIR) testing, surface area analysis (SAA), and scanning electron microscopy (SEM). The permeability value of four monolithic columns was in the good category: MIP 1 (24.01 mD), NIP 1 (56.43 mD), MIP 2 (23.03 mD), and NIP 2 (14.47 mD). The polymerisation process of these four monolithic imprinted columns was carried out perfectly, as shown by the absence of vinyl groups (1000 cm^-1 and 900 cm^-1) during FTIR testing. Based on SAA testing, the pores of the four polymers were classified as mesopores. The best monolithic column was MIP 1, as seen from the intercolumn and intracolumn reproducibility values and a % RSD <2.0%. The MIP 1 column was selective towards atenolol, as seen from the selectivity factor, imprinting factor (IF), and resolution (Rs) values. The IF values of MIP 1 were atenolol (204.62), metoprolol (3.36), and propranolol (1.27). The Rs value between atenolol and the analogue compounds was 7.23. The MIP 1 column can be used for the analysis of atenolol in blood serum samples with an average percentage recovery rate of 94.88 ± 4.43%.

Spectrofluorimetric method for atenolol determination based on gold nanoparticles

A simple and sensitive spectrofluorimetric method for determination of atenolol (ATE) using gold nanoparticles (AuNPs) was developed. The method is based on the quenching effect of atenolol on photoluminescence of AuNPs at λem = 705 nm. Variables affecting luminescence of gold nanoparticles such as the solvent, pH value and surfactant were studied and optimized. The method was preliminarily validated according to ICH guidelines. A linear correlation was recorded within the range of 1.0-10 mg mL-1 ATE with the coefficient of determination R2 of 0.999. The limit of detection and limit of quantitation for atenolol were found to be 0.87 and 2.64 mg mL-1, resp. Good recoveries in the range of 98.7-100.0 % were obtained for spiked samples. The proposed method was applied successfully to assaying atenolol in pharmaceuticals formulations.

Spectrofluorimetric determination of atenolol from human urine using high-affinity molecularly imprinted solid-phase extraction sorbent

This study presents a novel, sensitive and selective molecularly imprinted solid-phase extraction (MISPE)-spectrofluorimetric method for the removal and determination of atenolol from human urine. Molecularly imprinted and non-imprinted polymers were synthesized thermally using a radical chain polymerization technique and used as solid-phase extraction sorbents. Acrylic acid ethylene glycol dimethacrylate, dibenzoyl peroxide and dichloroethane were used as a functional monomer, cross-linker, initiator and porogen, respectively. The calibration curve was in the range of 0.10-2.0 μg/ml for the developed method. Limit of detection and limit of quantification values were 0.032 and 0.099 μg/ml, respectively. Owing to the selectivity of the MISPE technique and the sensitivity of spectrofluorimetry, trace levels of atenolol have been successfully determined from both organic and aqueous media. Relatively high imprinting factor (4.18) and recovery results (74.5-75.3%) were obtained. In addition, intra- and interday precision values were 0.38-1.03% and 0.47-2.05%, respectively, proving the precision of the proposed method. Thus, a selective, sensitive and simple MISPE-spectrofluorimetric method has been developed and applied to the direct determination of atenolol from human urine.

Design of highly sensitive phosphorescence sensor for determination of procaterol hydrochloride based on inhibition of KClO3 oxidation fluorescein isothiocyanate

Procaterol hydrochloride (Prh) can inhibit KClO3 oxidation of fluorescein isothiocyanate (FITC) to form a non-phosphorescent compound, which causes room temperature phosphorescence (RTP) of FITC in the system to enhance sharply the linear relationship between ∆Ip and the Prh content. Thus, a rapid response and highly sensitive phosphorescence sensor for the determination of Prh has been developed based on the inhibiting effect of Prh on KClO3 oxidation of FITC. This simple, high sensitivity (detection limit (LD) calculated by 3Sb /k was 0.019 fg/spot, sample volume 0.40 µl, corresponding concentration 4.8 × 10(-14) g ml(-1) ) and selective sensor with a wide linear range (0.080-11.20 g/spot) has been applied to detect Prh in blood samples, and the results were consistent with those obtained by high-performance liquid chromatography (HPLC). Simultaneously, the mechanism of the phosphorescence sensor for the detection of Prh was also investigated using infrared spectroscopy.