Green innovation in analytical chemistry: A sustainable densitometric HPTLC approach for the distinctive separation and quantification of structurally related abused drugs - tramadol, tapentadol, and venlafaxine - in seized pharmaceutical dosage forms

An innovative ecofriendly high-performance thin layer chromatographic (HPTLC) method with spectrophotometric detection for simultaneous determination of Tramadol (TMD), Tapentadol (TAP), and Venlafaxine (VEN) in seized dosage forms was presented. Our method was conducted to achieve separation following the optimal conditions: pre-coated silica gel plates using a green mobile phase (heptane: acetone: ammonia, 7:3:0.5 v/v), with absorbance scanning at 272 nm. The validation of the method was done following International Conference on Harmonization (ICH) guidelines, demonstrates linearity, accuracy, precision, selectivity, robustness, and system suitability. Separation was achieved with a detection limit of 0.34, 0.16, and 0.084 (ug/band) for TMD, TAP, and VEN, respectively, the method successfully analyzes seized samples. Trueness is confirmed through a high degree of similarity between HPTLC and gas chromatography results. The study's ecofriendly approach, simplicity, and selectivity position it as a promising method for efficient, on-site monitoring of seized samples.

An eco-friendly one-pot spectrofluorimetric approach for the facile determination of overactive bladder drug, tolterodine: Application to dosage forms and biological fluids

Tolterodine tartrate (TTD) was the first antimuscarinic medication developed exclusively for the treatment of overactive bladder syndrome and was approved by the FDA in 1998. As a result of the drug's extensive utilization within the local community following its authorization, there is a pressing need to develop and validate a spectrofluorometric method that is economically efficient, easily reproducible, environmentally sustainable, and possesses high sensitivity. The developed approach relies on enhancing the fluorescence intensity of TTD to reach a level 720 % higher than its initial value, achieved through the application of an aqueous sodium dodecyl sulfate (SDS) solution. A strong correlation was observed with a correlation coefficient of 0.9998 between the concentration of TTD and the fluorescence intensity within the range of 25.0-500.0 ng mL-1. This approach could be employed to quantify TTD in its pure form and to examine pharmaceutical tablets for the purposes of verifying uniform content. Additionally, it was utilized for the evaluation of TTD concentrations in spiked human plasma.

Ecological spectroscopic methodologies for quantifying co-administered drugs in human plasma by photochemical quantum mechanical simulation

Urinary tract infections (UTIs) constitute the second most prevalent bacterial infections in the elderly demographic. The treatment landscape involves various antibiotics targeting the causative organisms; nevertheless, the emergence of resistance significantly impacts therapeutic effectiveness. Presently, a fixed-dose pharmaceutical combination is advocated to optimize patient outcomes by mitigating the risks of bacterial resistance and associated side effects. Ofloxacin (OFL) and cefpodoxime proxetil (CPD) combinations, co-administered with flavoxate hydrochloride (FLV), have demonstrated efficacy in UTI cases, offering relief from concomitant symptoms. In the pharmaceutical market, fixed-dose combinations have gained prominence, driven by advantages such as enhanced patient medication adherence and compliance. In the realm of analytical chemistry, the integration of green practices in the initial phases of method development is exemplified by the Greenness by Design (GbD) strategy. While univariate spectroscopic methods are conventionally considered suboptimal compared to chemometric techniques for resolving intricate mixtures, GbD approach, when applied to UV spectroscopy, enable univariate methods to attain comparable or superior outcomes. GbD adopts a systematic approach to optimize experimental conditions, minimizing environmental impact and maximizing analytical performance. Critical to GbD applications in UV spectroscopy is solvent selection, influencing spectral resolution and measurement sensitivity. GbD employs a combination of in-vitro and in-silico experiments to evaluate solute-solvent interactions with underlying photochemical quantum phenomena affecting the resulting spectral morphology, identifying an optimal compromise solvent with high resolution and minimal ecological impact. Consequently, it facilitates the efficient resolution of spectral overlapping and determination of complex mixtures in UV spectroscopy using univariate methods. Comparative analysis with chemometric techniques, acknowledged as potent spectral resolving methods, demonstrated that GbD-based univariate methods performed equivalently. The methodology was validated according to ICH recommendations, establishing a linear quantitation range (2-30 μg/mL) and a limit of detection (0.355-0.414 μg/mL) for the three drugs in human plasma. The greenness of the developed methodology was affirmed through the AGREE assessment protocol, confirming its environmentally conscious attributes.

Eco-Friendly UV-Spectrophotometric Methods Employing Magnetic Nano-Composite Polymer for the Extraction and Analysis of Sexual Boosters in Adulterated Food Products: Application of Computer-Aided Design

BACKGROUND

Solid phase extraction (SPE) techniques, based on computationally designed magnetic-based multi-targeting molecular imprinted polymer (MT-MIP), combined with UV spectrophotometric approaches provide advantages in the examination of counterfeit samples.

OBJECTIVE

The current work describes an innovative and sustainable methodology for the simultaneous determination of tadalafil (TAD) and dapoxetine hydrochloride (DAP) in aphrodisiac counterfeit products (honey and instant coffee) utilizing SPE exploiting MT-MIP. Additionally, an innovative UV spectrophotometric method capable of resolving TAD in its pharmaceutical binary mixtures with DAP was developed. A novel computational approach was implemented to tailor the synthesis and design of the MT-MIP particles.

METHODS

We applied a newly developed UV spectrophotometric method which was based on a Fourier self-deconvolution (FSD) method coupled with the isoabsorptive point for determination of TAD and DAP in pharmaceutical dosage form. We also applied an SPE process based on MT-MIP designed particles, assisting in the analysis of both drugs in counterfeit food samples. The SPE process and the UV spectroscopic methodology were assessed regarding their greenness using the pioneering green analytical procedure index (GAPI), analytical greeness including sample preparation (AGREEprep) and AGREE tools. The synthesized MT-MIP particles were characterized by scanning electron microscopy and energy-dispersive x-ray spectroscopy.

RESULTS

The suggested spectrophotometric methods revealed a wide linear concentration range of 2-50 µg/mL with lower LODs in the range of 0.604-0.994 µg/mL. Additionally, the suggested method demonstrated the utmost sensitivity and eco-friendliness for their target in its mixed dosage form and counterfeit food products.

CONCLUSION

The SPE process and the developed analytical UV spectroscopic methodology were validated as per the ICH guidelines, and were found to be suitable for overseeing some counterfeiting activities in commercially available honey and instant coffee aphrodisiac products.

HIGHLIGHTS

An SPE method based on MT-MIP magnetic-based polymer and a UV spectroscopic method were successfully developed for analysis of TAD and DAP in different matrices.

Innovative and sustainable deconvoluted amplitude factor spectrophotometric method for the resolution of various severely overlapping pharmaceutical mixtures: Applying the complex-GAPI-tool

UV spectroscopy is considered the simplest, the most money and time investor technique in analytical research. Besides its lowered solvent and energy consumption leading to greener outcomes, its practicality is wide and suitable for a wide range of applications. Multicomponent mixtures are always representing themselves as a problematic challenge for any analytical technique fortunately UV spectroscopic methods found many ways to tackle these mixtures. Fourier self-deconvolution (FSD) was recently applied in UV spectroscopy as an effective tool for the resolution of binary mixtures unfortunately like any other method may fail to completely resolve severely overlapping mixtures. In this paper, we epitomize the newly developed deconvoluted amplitude factor (DAF) spectrophotometric approach which couples the concepts of both the FSD and the amplitude factor methods for the resolution of tadalafil (TAD) in its binary mixtures with dapoxetine hydrochloride (DAP) or tamsulosin hydrochloride (TAM). The embraced approach was assessed regarding its greenness utilizing different assessing protocols to give evident proof for its sustainability. The innovative approach showed an enhancement in the resolution of binary mixtures and showed high sensitivity as noticed from limits of detection and quantitation which were (0.374, 1.136 μg/mL), (0.269, 0.817 μg/mL), and (0.518, 1.569 μg/mL) for TAD, DAP, and TAM, respectively. The method was validated as per ICH guidelines recommendations and also was statistically compared with recently reported methods which revealed no statistically significant difference. A very handy and reader-friendly data presentation approach was followed for the ease of statistical data interpretation and evaluation.

Synthesis, Physicochemical Characterization using a Facile Validated HPLC Quantitation Analysis Method of 4-Chloro-phenylcarbamoyl-methyl Ciprofloxacin and Its Biological Investigations

A novel derivative of ciprofloxacin (Cpx) was synthesized and characterized using various analytical techniques, including FT-IR spectroscopy, UV-Vis spectroscopy, TEM and SEM analysis, 1H NMR, 13C NMR, and HPLC analysis. The newly prepared Cpx derivative (Cpx-Drv) exhibited significantly enhanced antibacterial properties compared to Cpx itself. In particular, Cpx-Drv demonstrated a 51% increase in antibacterial activity against S. aureus and a 30% improvement against B. subtilis. It displayed potent inhibitory effects on topoisomerases II (DNA gyrase and topoisomerase IV) as potential molecular targets, with IC50 values of 6.754 and 1.913 µg/mL, respectively, in contrast to Cpx, which had IC50 values of 2.125 and 0.821 µg/mL, respectively. Docking studies further supported these findings, showing that Cpx-Drv exhibited stronger binding interactions with the gyrase enzyme (PDB ID: 2XCT) compared to the parent Cpx, with binding affinities of -10.3349 and -7.7506 kcal/mole, respectively.

Computer-Aided Design of Eco-Friendly Imprinted Polymer Decorated Sensors Augmented by Self-Validated Ensemble Modeling Designs for the Quantitation of Drotaverine Hydrochloride in Dosage Form and Human Plasma

BACKGROUND

Computationally designed molecular imprinted polymer (MIP) incorporation into electrochemical sensors has many advantages to the performance of the designed sensors. The innovative self-validated ensemble modeling (SVEM) approach is a smart machine learning-based (ML) technique that enables the design of more accurate predictive models using smaller data sets.

OBJECTIVE

The novel SVEM experimental design methodology is exploited here exclusively to optimize the composition of four eco-friendly PVC membranes augmented by a computationally designed magnetic molecularly imprinted polymer to quantitatively determine drotaverine hydrochloride (DVN) in its combined dosage form and human plasma. Furthermore, the application of hybrid computational simulations such as molecular dynamics and quantum mechanical calculations (MD/QM) is a time-saving and eco-friendly provider for the tailored design of the MIP particles.

METHOD

Here, for the first time, the predictive power of ML is assembled with computational simulations to develop four PVC-based sensors decorated by computationally designed MIP particles using four different experimental designs known as central composite, SVEM-LASSO, SVEM-FWD, and SVEM-PFWD. The pioneering AGREE approach further assessed the greenness of the analytical methods, proving their eco-friendliness.

RESULTS

The proposed sensors showed decent Nernstian responses toward DVN in the range of 58.60-59.09 mV/decade with a linear quantitative range of 1 × 10-7 - 1 × 10-2 M and limits of detection in the range of 9.55 × 10-8 to 7.08 × 10-8 M. Moreover, the proposed sensors showed ultimate eco-friendliness and selectivity for their target in its combined dosage form and spiked human plasma.

CONCLUSIONS

The proposed sensors were validated in accordance with International Union of Pure and Applied Chemistry (IUPAC) recommendations, proving their sensitivity and selectivity for drotaverine determination in dosage form and human plasma.

HIGHLIGHTS

This work presents the first ever application of both the innovative SVEM designs and MD/QM simulations in the optimization and fabrication of drotaverine-sensitive and selective MIP-decorated PVC sensors.

Greenness-by-design approach for developing novel UV spectrophotometric methodologies resolving a quaternary overlapping mixture

Greenness-by-design (GbD) is an approach that integrates green chemistry principles into the method development stage of analytical processes, aiming to reduce their environmental impact. In this work, we applied GbD to a novel univariate double divisor corrected amplitude (DDCA) method that can resolve a quaternary pharmaceutical mixture in a fixed-dose polypill product. We also used a genetic algorithm as a chemometric modeling technique to select the informative variables for the analysis of the overlapping mixture. This resulted in more accurate and efficient predictive models. We used a computational approach to study the effect of solvents on the spectral resolution of the mixture and to minimize the spectral interferences caused by the solvent, thus achieving spectral resolution with minimal analytical effort and ecological footprint. The validated methods showed wide linear concentration ranges for the four components (1-30 µg/mL for losartan, 2.5-30 µg/mL for atorvastatin and aspirin, and 2.5-35 µg/mL for atenolol) and achieved high scores on the hexagon and spider charts, demonstrating their eco-friendliness.

Fast Sensitive and Accurate Analysis of the Most Common Synthetic Food Colorants in 65 Egyptian Commercial Products Using New HPLC–DAD and UPLC-ESI–MS/MS Methods

Overexposure to food colorants above the allowed daily intake (ADI) level can provoke hyperactivity and other disturbed behaviors especially in children. Two new methods were developed to separate five synthetic colorants, which were Tartrazine (E102), Sunset Yellow (E110), Allura Red (E129), Carmoisine (E122), and Brilliant Blue (E133). They are labeled on a large variety of commercial food products in the Egyptian market without mentioning their definite concentrations. Therefore, there was a real need to determine these colorants with simple, accurate, and fast methods. This is the first study to determine these colorants in a wide variety of food products present in the Egyptian market. The HPLC approach with photodiode array detection was developed to quantify these colorants, on a C18 column, with a mobile phase composed of acetonitrile and water containing 1% ammonium acetate (pH 6.8), separation was carried out using a gradient program. The colorants were eluted and efficiently separated within 9 min. Then, as a complementary technique to HPLC, the UPLC-ESI–MS/MS approach was developed for identification and accurate mass measurement of the colorants found in high concentrations, the colorants were obtained simultaneously in negative mode, the run time was only 3 min. These developed methods were validated according to ICH recommendations and they were applied to analyze 65 food products including jelly powder, puddings, ice cream powders, concentrated soft drink powders, carbonated drinks, chewing gums, and sugar confectionery.

HPLC-UV and UPLC-MS/MS methods for the simultaneous analysis of sildenafil, vardenafil, and tadalafil and their counterfeits dapoxetine, paroxetine, citalopram, tramadol, and yohimbine in aphrodisiac products

In recent times, the counterfeiting of pharmaceuticals has been considered a serious trouble especially in developing countries that acquire poor inspection programs. Sildenafil, vardenafil and tadalafil (phosphodiesterase type 5 inhibitors) products have gained wide popularity in treating sexual disorders, for which they are subjected to counterfeiting. For this purpose, a simple, rapid, and novel HPLC method with ultraviolet detection has been simply developed for the simultaneous determination of vardenafil, sildenafil, and tadalafil, and their counterfeits (dapoxetine, paroxetine, citalopram, tramadol and yohimbine) in pharmaceutical dosage forms and counterfeit products such as instant coffee and honey. The separation was carried out on a C18 column, with acetonitrile and an aqueous 0.05% formic acid solution as the mobile phase with a gradient program and at a flow rate of 1 mL min-1. UV detection was accurately set at 230 nm. The total run time was 11 min for elution of these eight drugs. A UPLC-MS/MS method was also developed, by which compounds were separated in only 6 min, and it was used as a confirmatory tool for studied compounds by identification of their mass spectra. Proposed methods were validated by following ICH guidelines. Both methods were found to be linear, specific, precise and accurate, and they were efficiently applied to analyze 50 commercial products including honey sachets, instant coffee and pharmaceutical products marketed as aphrodisiacs and suspected to contain PDE5-inhibitors.