Spectrophotometric Determination of Aspirin and Omeprazole in the presence of Salicylic Acid as a Degradation Product: A Comparative Evaluation of Different Univariate/Multivariate Post Processing Algorithms

An amplified electrochemical sensor employing one-step synthesized nickel-copper-zinc ferrite/carboxymethyl cellulose/graphene oxide nanosheets composite for sensitive analysis of omeprazole

In this work, a signal amplification strategy was designed by the fabrication of a highly sensitive and selective electrochemical sensor based on nickel-copper-zinc ferrite (Ni0.4Cu0.2Zn0.4Fe2O4)/carboxymethyl cellulose (CMC)/graphene oxide nanosheets (GONs) composite modified glassy carbon electrode (GCE) for determination of omeprazole (OMP). The one-step synthesized Ni0.4Cu0.2Zn0.4Fe2O4/CMC/GONs nanocomposite was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy and X-ray diffraction techniques. Then, the Ni0.4Cu0.2Zn0.4Fe2O4/CMC/GONs/GCE was applied to study the electrochemical behavior of the OMP. Electrochemical data show that the Ni0.4Cu0.2Zn0.4Fe2O4/CMC/GONs/GCE exhibits superior electrocatalytic performance on the oxidation of OMP compared with bare GCE, GONs/GCE, CMC/GONs/GCE and MFe2O4/GCE (M = Cu, Ni and Zn including single, double and triple of metals) which can be attributed to the synergistic effects of the nanocomposite components, outstanding electrical properties of Ni0.4Cu0.2Zn0.4Fe2O4 and high conductivity of CMC/GONs as well as the further electron transport action of the nanocomposite. Under optimal conditions, the Ni0.4Cu0.2Zn0.4Fe2O4/CMC/GONs/GCE offers a high performance toward the electrodetermination of OMP with the wide linear-range responses (0.24-5 and 5-75 μM), lower detection limit (0.22 ± 0.05 μM), high sensitivity (1.1543 μA μM-1 cm-2), long-term signal stability and reproducibility (RSD = 2.54%). It should be noted that the Ni0.4Cu0.2Zn0.4Fe2O4/CMC/GONs/GCE sensor could also be used for determination of OMP in drug and biological samples, indicating its feasibility for real analysis.

Spider diagram and sustainability evaluation of UV-methods strategy for quantification of aspirin and sildenafil citrate in the presence of salicylic acid in their bulk and formulation

The cutting-edge combination of aspirin (ASA) and sildenafil citrate (SIC) has been presented as a suggested dosage form for the treatment of thin endometrium and erectile dysfunction, particularly in patients with cardiovascular diseases. However, ASA is highly sensitive to degradation into its major deterioration product, known as salicylic acid (SA). Consequently, it is eminently essential to evolve approaches for the synchronous quantification of ASA and SIC in the presence of SA. The main objective of this work is to develop three approaches for the synchronous quantification of ASA and SIC in the presence of SA in their commixtures and suggested formulations without any prior separation. Three green UV-methods were employed for the synchronous quantification, namely: Dual Wavelength in Ratio Spectra (DW-RS), Advanced Amplitude Centering (AAC), and Double Divisor of Ratio Difference Derivative (DDRD-D₁). In DW-RS and AAC two-wavelength manipulation was used for resolution, while in DDRD-D₁ only an appropriate wavelength for the synchronous quantification of the triplex commixture was used. All approaches can be able to resolve the highly interfering spectrum of the three components presented in the triplex commixture. Good linearity was inspected in the range of 20.0-100.0, 5.0-50.0, and 4.0-60.0 μg/mL for the ASA, SIC, and SA, respectively. All developed approaches have been advocated in accordance with ICH guidelines. All results from these approaches are presented and statistically reconciled with the proclaimed HPLC method, with no considerable differences. Furthermore, the approaches' eco-friendliness was predestined by Analytical Greenness (AGREE), and the complex GAPI. Moreover, the sustainability of the used solvent was evaluated by Green Solvents Selecting Tool (GSST); in addition, the greenness of the solvent was evaluated by Greenness Index tool with a spider diagram. The suggested UV-methods may be employed for routine quality control studies of the suggested formulations ASA & SIC since they were considered sustainable, economical, and effective.

A New Chemometrically Assisted UV Spectrophotometric Method for Simultaneous Determination of Tamsulosin and Dutasteride in Their Pharmaceutical Mixture

Background

Tamsulosin (TAM) and dutasteride (DUT) are ranked among the most frequently prescribed therapies in urology. Interestingly, studies have also been carried out on TAM/DUT in terms of their ability to protect against recent COVID-19. However, very few studies were reported for their simultaneous quantification in their combined dosage form and were mainly based on chromatographic analysis. Subsequently, it is very important to offer a simple, selective, sensitive, and rapid method for the quantification of TAM and DUT in their challenging dosage form.

Objective

In this study, a new chemometrically assisted ultraviolet (UV) spectrophotometric method has been presented for the quantification of TAM and DUT without any prior separation.

Method

For the calibration set, a partial factorial experimental design was used, resulting in 25 mixtures with central levels of 20 and 25 μg/mL for TAM and DUT, respectively. In addition, to assess the predictive ability of the developed approaches, another central composite design of 13 samples was used as a validation set. Post-processing by chemometric analysis of the recorded zero-order UV spectra of these sets has been applied. These chemometric approaches include partial least-squares (PLS) and genetic algorithm (GA), as an effective variable selection technique, coupled with PLS.

Results

The models’ validation criteria displayed excellent recoveries and lower errors of prediction.

Conclusions

The proposed models were effectively used to determine TAM/DUT in their combined dosage form, and statistical comparison with the reported method revealed satisfactory results.

Highlights

Overall, this work presents powerful simple, selective, sensitive, and precise methods for simultaneous quantification of TAM/DUT in their dosage form with satisfactory results. The predictive ability and accuracy of the developed methods offer the opportunity to be employed as a quality control technique for the routine analysis of TAM/DUT when chromatographic instruments are not available.

Innovative Earth-Friendly UV-Spectrophotometric Technique for In Vitro Dissolution Testing of Miconazole Nitrate and Nystatin in Their Vaginal Suppositories: Greenness Assessment

Background

The combined mixture of miconazole nitrate (MIC) and nystatin (NYS) has proven its efficiency as a prodigious remedy to cure women’s frequent infections: vaginal mycosis and vaginal candidiasis.

Objective

A novel green spectrophotometric technique, namely the Fourier self-deconvolution method (FSD), was employed for the quantitative determination of MIC and NYS in their pure and pharmaceutical forms without prior separation. Moreover, the proposed technique was first employed to study the dissolution profile of the cited drugs in their pharmaceutical formulation according to FDA recommendations without excipient interference.

Method

The FSD method is based on a simple mathematical manipulation of zero-order spectra of the cited drugs, which suffered from severe overlapping, so zero-order spectra of the cited drugs were deconvoluted using the Fourier wavelet function in spectrophotometer software. The deconvoluted amplitudes for MIC and NYS were measured at 255 nm and 320 nm, respectively.

Results

Linearity ranges were 70–700 µg/mL for MIC and 1–25 µg/mL for NYS. The greenness of the proposed technique was assessed using two assessment tools, namely eco-scale scoring and green analytical procedure index (GAPI), revealing the excellent greenness of this technique. The proposed technique was validated consistent with ICH guidelines and statistically compared to the reported method with no significant differences between them.

Conclusions

The proposed technique has advantages of being simple, time-saving, and noting need any modification to be suitable for quantitative analysis of MIC and NYS in both pharmaceutical and laboratory mixtures.

Highlights

An innovative FSD method was developed for quantitative analysis of MIC and NYS in their synthetic and pharmaceutical mixtures and applied for in vitro dissolution testing of their pharmaceutical mixture, producing satisfactory results.