Monosaccharide Analysis After One-Pot Derivatization Followed by Reverse-Phase Liquid Chromatography Separation and UV/Vis Detection.

Derivatization of monosaccharides with 1-phenyl-3-methyl-5-pyrazolone (PMP) introduces two chromophores per sugar molecule. Their separation on a superficially porous C18 reverse-phase column, using common liquid chromatography equipment, results in short analysis times (under 20 min) and high sensitivity (limit of quantitation 1 nmol). This method allows for complex monosaccharide mixtures to be separated and quantified using a reasonably simple and safe derivatization procedure.

Augmented least squares, a powerful chemometric approach for the spectroscopic analysis of the antiretroviral therapy abacavir, lamivudine and dolutegravir in their ternary mixture.

Augmented least squares models such as concentration residual augmented classical least squares (CRACLS) and spectral residual augmented classical least squares (SRACLS) are powerful chemometric approaches that can be applied for spectroscopic analysis of many pharmaceutical compounds. Herein, both CRACLS and SRACL have been employed for UV spectral analysis of three antiretroviral therapy namely abacavir (ACV), lamivudine (LMV) and dolutegravir (DTG) in their ternary mixture. A partial factorial design has been utilized for calibration set construction then both CRACLS and SRACLS models have been optimized regarding the number of iterations and principal components, respectively, using a leave-one-out cross-validation procedure. It was found that a higher number of iterations and principal components were required for modelling the minor component DTG indicating more augmentation procedures to improve the models' accuracy. Validation of the proposed models was performed using external validation set of 13 mixtures and different validation parameters have been evaluated regarding models' predictive abilities. Both models showed excellent performance for analyzing ACV and LMV with relative root mean square error of prediction (RRMSEP) below 2 %. However, higher RRMSEP values around 5 % were observed for the minor component DTG suggesting that these models should be utilized with caution when analyzing minor components in mixtures. Furthermore, the suggested models have been applied for analyzing ACV, LMV and DTG in their pharmaceutical formulation and excellent agreement was observed between the suggested models and the reported chromatographic method posing these models as powerful chemometric approaches for quality control analysis of many pharmaceutical compounds.

Rapid and Highly Efficient Separation of i-Motif DNA Species by CE-UV and Multivariate Curve Resolution.

The i-motif is a class of nonstandard DNA structure with potential biological implications. A novel capillary electrophoresis with an ultraviolet absorption spectrophotometric detection (CE-UV) method has been developed for the rapid analysis of the i-motif folding equilibrium as a function of pH and temperature. The electrophoretic analyses are performed in reverse polarity of the separation voltage with 32 cm long fused silica capillaries permanently coated with hydroxypropyl cellulose (HPC), after an appropriate conditioning procedure was used to achieve good repeatability. However, the electrophoretic separation between the folded and unfolded conformers of the studied cytosine-rich i-motif sequences (i.e., TT, Py39WT, and nmy01) is compromised, especially for Py39WT and nmy01, which result in completely overlapped peaks. Therefore, deconvolution with multivariate curve resolution-alternating least-squares (MCR-ALS) has been required for the efficient separation of the folded and unfolded species found at different concentration levels at pH 6.5 and between 12 and 40 °C, taking advantage of the small dissimilarities in the electrophoretic mobilities and UV spectra levels. MCR-ALS has also provided quantitative information that has been used to estimate melting temperatures (Tm), which are similar to those determined by UV and circular dichroism (CD) spectroscopies. The obtained results demonstrate that CE-UV assisted by MCR-ALS may become a very useful tool to get novel insight into the folding of i-motifs and other complex DNA structures.

[Study of the possibility of emtricitabine extraction from biomaterial]. / Izuchenie vozmozhnosti ekstraktsii emtritsitabina iz biologicheskogo materiala.

THE AIM OF THE STUDY: Is to investigate the opportunity of emtricitabine extraction from biomaterial and to develop method of emtricitabine chemicotoxicological analysis while acute poisoning. This research represents the methods of emtricitabine isolation from urine, plasma and liver samples (rats of Wistar line weighing 180 g) using liquid-liquid extraction. The identification and quantitation methods of emtricitabine in extractions by thin-layer chromatography, ultraviolet spectrophotometry and high-performance liquid chromatography methods were described. The emtricitabine was found extracted from urine with a therapeutic dose of 6.65±2.21 µg/ml and a toxic dose 35.81±1.05 µg/ml, from plasma with a therapeutic dose of 2.91±0.19 µg/ml and a toxic dose of 16.88±0.90 µg/ml.

Spectroscopic and Spectroelectrochemical Studies of Hexapentyloxytriphenylene-A Model Discotic Molecule.

The electrochemical and spectroelectrochemical properties of the discotic mesogen 2,3,6,7,10,11-pentyloxytriphenylene (H5T) were studied with the use of cyclic voltammetry combined with UV-Vis and electron paramagnetic resonance (EPR) spectroscopy in solution. The UV-Vis absorption spectroscopy of H5T in dichloromethane showed its monomeric state in a concentration range up to 10-3 mol dm-3. The reversible process of the electrochemical formation of the radical cation was evidenced within the experimentally accessible potential window. The in situ UV-Vis spectroelectrochemical measurements further enabled identification of the product of the redox process and evaluation of the effect of aggregation in the concentration range of 5 × 10-3 mol dm-3. The results are discussed in the frame of solvent effects on the self-assembly propensity of solute molecules, in a wide range of concentrations. In particular, the crucial role of the solvent polarity is indicated, which contributes to the understanding of solution effects and pre-programming of supramolecular organic materials, in particular anisotropic disc-shaped hexa-substituted triphenylenes.

Investigation of the interaction between the functionalized mesoporous silica nanocarriers and bovine serum albumin via multi-spectroscopy.

It is well known that the physicochemical properties of nanocarriers, which are closely related to the surface modification of nanoparticles, have crucial impacts on their biological effects. Herein, the interaction between functionalized degradable dendritic mesoporous silica nanoparticles (DDMSNs) and bovine serum albumin (BSA) was investigated for probing into the nanocarriers' potential toxicity using multi-spectroscopy such as ultraviolet/visible (UV/Vis), synchronous fluorescence, Raman and circular dichroism (CD) spectroscopy. BSA, owing to its structural homology and high sequence similarity with HSA, was employed as the model protein to study the interactions with DDMSNs, amino-modified DDMSNs (DDMSNs-NH2) and hyaluronic acid (HA) coated nanoparticles (DDMSNs-NH2-HA). It was found that the static quenching behavior of DDMSNs-NH2-HA to BSA was accompanied by an endothermic and hydrophobic force-driven thermodynamic process, which was confirmed by fluorescence quenching spectroscopic studies and thermodynamic analysis. Furthermore, the conformational variations of BSA upon interaction with nanocarriers were observed by combination of UV/Vis, synchronous fluorescence, Raman and CD spectroscopy. The microstructure of amino residues in BSA changed due to the existence of nanoparticles, for example, the amino residues and hydrophobic groups exposed to microenvironment and the alpha helix (α-helix) content of BSA decreased. Specially, through thermodynamic analysis, the diverse binding modes and driving forces between nanoparticles and BSA were discovered because of different surface modifications on DDMSNs, DDMSNs-NH2 and DDMSNs-NH2-HA. We believe that this work can promote the interpretation of mutual impact between nanoparticles and biomolecules, which will be in favor of predicting the biological toxicity of nano-DDS and engineering functionalized nanocarriers.

Machine Learning Models for Predicting Molecular UV-Vis Spectra with Quantum Mechanical Properties.

Accurate understanding of ultraviolet-visible (UV-vis) spectra is critical for the high-throughput synthesis of compounds for drug discovery. Experimentally determining UV-vis spectra can become expensive when dealing with a large quantity of novel compounds. This provides us an opportunity to drive computational advances in molecular property predictions using quantum mechanics and machine learning methods. In this work, we use both quantum mechanically (QM) predicted and experimentally measured UV-vis spectra as input to devise four different machine learning architectures, UVvis-SchNet, UVvis-DTNN, UVvis-Transformer, and UVvis-MPNN, and assess the performance of each method. We find that the UVvis-MPNN model outperforms the other models when using optimized 3D coordinates and QM predicted spectra as input features. This model has the highest performance for predicting UV-vis spectra with a training RMSE of 0.06 and validation RMSE of 0.08. Most importantly, our model can be used for the challenging task of predicting differences in the UV-vis spectral signatures of regioisomers.

Effect of Cu2+ and Al3+ on the interaction of chlorogenic acid and caffeic acid with serum albumin.

Despite the phenolic acids' health benefits, their interactions with proteins are still unclear. In this study, the interactions of Bovine Serum Albumin (BSA) with chlorogenic acid (CHA), caffeic acid (CA), and their Al3+, Cu2+ complexes were studied by using circular dichroism (CD) spectroscopy, fluorescence spectroscopy, and UV/Vis spectroscopy. It was found that esterification of carboxyl group of CA with quinic acid increased the binding affinities for BSA. After chelating with Cu2+ and Al3+, both CHA and CA exhibited high binding affinities for BSA. CHA could form CHA-Cu2 and CHA-Al2 complex with Cu2+ and Al3+. The result of CD spectroscopy demonstrated that the binding of CHA and Al3+ with BSA contributed to the folding of BSA secondary structure. In addition, with the presence of CHA, binding with Al3+ could also induce changes in BSA conformation. The binding sites of both CHA and CA were closed to Trp213.

One-step rapid colorimetric detection of K+ using silver nanoparticles modified by crown ether.

Urinary potassium is an important parameter in clinical health diagnosis. Rapid and convenient detection of potassium ions (K+) in urine is essential for personal healthcare and health management. Here, crown ether (4-aminodibenzo-18-crown-6, ADC) modified silver nanoparticles (ADC-Ag NPs) were successfully prepared for one-step rapid colorimetric detection of urinary potassium. The detection mechanism is as follows: due to the matching sizes of the diameter of K+ and the cavity in crown ether 6, K+ is encapsulated between the cavities of two crown ethers, resulting in the clumping of ADC-Ag NPs and the color of the solution being altered. The colorimetric detection method has a fast response and is completed within 20 minutes. It also shows good selectivity and interference immunity. The lowest detectable concentration is 20 µM with the naked eye and 2.16 µM for UV-vis absorption spectroscopy. A good linear relationship (R2 = 0.9931) between the absorption intensity ratio and K+ concentration (0-100 µM) indicates that this colorimetric probe can be used to detect K+. The method was also applied for quantitative analysis of K+ in real urine samples with recovery between 116 and 120%.

Rapid Quantitative Determination Control Male Sexual Dysfunction Drug Content of Sildenafil and Tramadol Mixture by Spectrophotometry Along With Smart Chemometrics Approaches Compared to the HPLC Reference Method.

BACKGROUND: There are reports for the simultaneous estimation of sildenafil (SIL) and tramadol (TM) using chromatographic techniques. Some limitations of these methods are high cost and time, more usage of pollutant solvents, and complicated instruments. OBJECTIVE: Simultaneous determination of SIL and TM in the anti-sexual dysfunction pharmaceutical formulation using rapid and smart chemometrics approaches along with spectrophotometry. METHOD: In this study, a spectrophotometric analysis method based on continuous wavelet transform (CWT), partial least-squares (PLS), and radial basis function neural network (RBF-NN) was presented. RESULTS: In the CWT method, the Symlet (Sym2) and Daubechies (db2) wavelet families with wavelengths of 268 and 221 nm were considered the best families for SIL and TM, respectively. The limit of detection (LOD) and limit of quantitation (LOQ) values were found to be 0.0185, 0.0054 µg/mL and 0.0458, 0.3092 µg/mL for SIL and TM, respectively. The mean recovery values were 101.06 and 101.49% for SIL and TM, respectively. The results of PLS revealed that the root-mean-square error (RMSE) of SIL and TM was 0.0286 and 0.0635, respectively. Also, the mean recovery of both drugs was obtained over 99%. The mean square error (MSE) of RBF-NN was 5.88 × 10-29 and 4.61 × 10-27 for SIL and TM, respectively. CONCLUSIONS: A statistical comparative study conducted for the proposed methods with the high-performance liquid chromatography (HPLC) technique demonstrated no significant difference between these methods. The suggested approaches were simple, fast, accurate, and affordable. HIGHLIGHTS: Three smart UV spectrophotometric methods based on chemometrics were presented to determine SIL and TM simultaneously. The efficient chemometrics methods, including CWT, PLS, and RBF-NN, were used. The mentioned methods are rapid, simple, inexpensive, and accurate. The comparison was performed between the proposed models and HPLC technique.

Online water quality monitoring based on UV-Vis spectrometry and artificial neural networks in a river confluence near Sherfield-on-Loddon.

Water quality monitoring is very important in agricultural catchments. UV-Vis spectrometry is widely used in place of traditional analytical methods because it is cost effective and fast and there is no chemical waste. In recent years, artificial neural networks have been extensively studied and used in various areas. In this study, we plan to simplify water quality monitoring with UV-Vis spectrometry and artificial neural networks. Samples were collected and immediately taken back to a laboratory for analysis. The absorption spectra of the water sample were acquired within a wavelength range from 200 to 800 nm. Convolutional neural network (CNN) and partial least squares (PLS) methods are used to calculate water parameters and obtain accurate results. The experimental results of this study show that both PLS and CNN methods may obtain an accurate result: linear correlation coefficient (R2) between predicted value and true values of TOC concentrations is 0.927 with PLS model and 0.953 with CNN model, R2 between predicted value and true values of TSS concentrations is 0.827 with PLS model and 0.915 with CNN model. CNN method may obtain a better linear correlation coefficient (R2) even with small number of samples and can be used for online water quality monitoring combined with UV-Vis spectrometry in agricultural catchment.

Nanohydrophobic Interaction Chromatography Coupled to Ultraviolet Photodissociation Mass Spectrometry for the Analysis of Intact Proteins in Low Charge States.

The direct correlation between proteoforms and biological phenotype necessitates the exploration of mass spectrometry (MS)-based methods more suitable for proteoform detection and characterization. Here, we couple nano-hydrophobic interaction chromatography (nano-HIC) to ultraviolet photodissociation MS (UVPD-MS) for separation and characterization of intact proteins and proteoforms. High linearity, sensitivity, and sequence coverage are obtained with this method for a variety of proteins. Investigation of collisional cross sections of intact proteins during nano-HIC indicates semifolded conformations in low charge states, enabling a different dimension of separation in comparison to traditional, fully denaturing reversed-phase separations. This method is demonstrated for a mixture of intact proteins from Escherichia coli ribosomes; high sequence coverage is obtained for a variety of modified and unmodified proteoforms.

Highly sensitive trace oxygen sensing based on far-ultraviolet absorption spectroscopy.

High-sensitivity trace oxygen sensing based on far-ultraviolet absorption spectroscopy was realized. The far-ultraviolet absorption spectrum of oxygen in the wavelength range of 170-200 nm at normal pressure was measured, and the maximum oscillation absorption peak occurred close to 180.18 nm. Through error analysis, the optimal wavelength range for accurate and sensitive oxygen measurements by ultraviolet absorption spectroscopy was identified as 180-189 nm. A total column (CL) calibration curve for oxygen was established, and the maximum optical path length (L1) of the system was determined to be 0.75(3) m by comparing the oxygen absorption with and without the sample cell. The oxygen detection sensitivity was 232 m-1, and the lowest detection limit was 12 ppm at the L1 optical path length. The highly sensitive trace oxygen sensing based on far-ultraviolet absorption spectroscopy exhibited significant potential for application with regard to nitrogen protection.

Investigating Comproportionation in Multielectron Transfers via UV-Visible Spectroelectrochemistry: The Electroreduction of Anthraquinone-2-sulfonate in Aqueous Media.

UV-vis spectroelectrochemistry is assessed as a tool for the diagnosis and quantitative in situ investigation of the incidence of comproportionation in multielectron transfer processes. Thus, the sensitivity of the limiting current chronoabsorptometric signals related to the different redox states to the comproportionation kinetics is studied theoretically for different working modes (normal and parallel light beam arrangements) and mass transport regimes (from semi-infinite to thin layer diffusion). The theoretical results are applied to the spectroelectrochemical study of the two-electron reduction of the anthraquinone-2-sulfonate in alkaline aqueous solution, tuning the thermodynamic favorability of the comproportionation reaction through the electrolyte cation. The quantitative analysis of the experimental results reveals the occurrence of comproportionation in the three media examined, showing different kinetics depending on the cationic species in solution.

Chemometric Quality Assessment of Doxylamine Succinate With Its Degradation Product: Implementation of Two Predictive Models on UV-Spectrophotometric Data of Anti-Emetic Binary Mixture.

BACKGROUND: The combination of pyridoxine hydrochloride (PYR) and doxylamine succinate (DOX) as an antiemetic binary mixture is used to treat nausea and vomiting during pregnancy. OBJECTIVE: Two validated, accurate, and selective chemometric models were developed to assay binary mixture in the presence of DOX oxidative degradation product (DOX DEG) that could be characterized using LC-MS. METHODS: Partial least squares (PLS) regression and principal component regression (PCR) were selected for the determination of our binary mixture in presence of degradation. To exhibit a training set of 25 mixtures that had various percentages of tested substances in five level 3 variables, an experimental design was chosen. A set of 18 synthetic mixtures in the concentration range 10.0-50.0 µg/mL, 12.00-20.0 µg/mL, and 6.0-30.0 µg/mL for PYR, DOX, and DOX DEG, respectively, were used in the construction of the calibration models. Then set of seven synthetic mixtures with different concentrations were used in the construction of the validation models. RESULTS: In validation samples with low root mean square error of prediction (RMSEP), the suggested models successfully predicted the concentrations of our drugs. The models developed were evaluated by RMSEP calculation, and the values obtained were 0.341, 0.196, and 0.388 for PYR, DOX, and DOX DEG, respectively, using PLS. While using PCR, RMSEP calculation and the values obtained were 0.400, 0.256, and 0.375 for PYR, DOX, and DOX DEG, respectively. The developed models were validated according to ICH strategies. CONCLUSIONS: The corresponding methods are suitable to determine PYR and DOX in pure form, pharmaceutical dosage form, and in the presence of DOX DEG product. HIGHLIGHTS: The study of drug breakdown pathways is very important nowadays, so even in the presence of degradation and extreme spectral overlapping, the suggested PLS and PCR spectrophotometric approaches were able to identify PYR and DOX.

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.

Environmental sustainable mathematically processed UV spectroscopic methods for quality control analysis of remogliflozin and teneligliptin: Evaluation of greenness and whiteness.

Environmental sustainable analytical methods were developed by mathematical modification of UV absorption spectra for quality control study of multicomponent formulations consisting of remogliflozin (REM) and teneligliptin (TEN), with good sensitivity and selectivity. Then analytes were quantified by measuring the peak amplitude of the first derivative spectra at zero crossing points at 230.2 nm and 213.8 nm for REG and TEN in the first derivative method. The second method involves the formation of ratio spectra and taking the absorption difference at two selected wavelengths of peak and trough of a spectrum. In the ratio first derivative method peak amplitudes were measured at 235.2 nm and 259.1 nm for simultaneous quantification of REM and TEN respectively. The fourth method was based on the measurement of the peak amplitude of zero-order spectra of analytes generated from the mixture spectrum by subtraction of a constant from the ratio spectrum followed by multiplication with divisor spectrum, Further, the proposed methods were validated systematically to confirm the linearity, precession, accuracy, sensitivity, and selectivity. Finally, validated UV spectroscopic methods were applied for simultaneous quantification of REM and TEN from formulation, and laboratory mixed solutions and statistically compared with the reported HPLC method. Further, recently developed AGREE, Hexagonal greenness and white analytical chemistry, a whiteness evaluation tools were applied to the proposed UV spectroscopic methods and found to be safer analytical methods, compared to the reported expensive, time-consuming and toxic HPLC method. Hence, proposed UV spectroscopic methods could be used for routine quality control of formulations containing REM and TEN.

Two Green Micellar HPLC and Mathematically Assisted UV Spectroscopic Methods for the Simultaneous Determination of Molnupiravir and Favipiravir as a Novel Combined COVID-19 Antiviral Regimen.

Following the spread of the COVID-19 pandemic crisis, a race was initiated to find a successful regimen for postinfections. Among those trials, a recent study declared the efficacy of an antiviral combination of favipiravir (FAV) and molnupiravir (MLP). The combined regimen helped in a successful 60% eradication of the SARS-CoV-2 virus from the lungs of studied hamster models. Moreover, it prevented viral transmission to cohosted sentinels. Because both medications are orally bioavailable, the coformulation of FAV and MLP can be predicted. The developed study is aimed at developing new green and simple methods for the simultaneous determination of FAV and MLP and then at their application in the study of their dissolution behavior if coformulated together. A green micellar HPLC method was validated using an RP-C18 core-shell column (5 µm, 150 × 4.6 mm) and an isocratic mixed micellar mobile phase composed of 0.1 M SDS, 0.01 M Brij-35, and 0.02 M monobasic potassium phosphate mixture and adjusted to pH 3.1 at 1.0 mL min-1 flow rate. The analytes were detected at 230 nm. The run time was less than five minutes under the optimized chromatographic conditions. Four other multivariate chemometric model methods were developed and validated, namely, classical least square (CLS), principal component regression (PCR), partial least squares (PLS-1), and genetic algorithm-partial least squares (GA-PLS-1). The developed models succeeded in resolving the great similarity and overlapping in the FAV and MLP UV spectra unlike the traditional univariate methods. All methods were organic solvent-free, did not require extraction or derivatization steps, and were applied for the construction of the simultaneous dissolution profile for FAV tablets and MLP capsules. The methods revealed that the amount of the simultaneously released cited drugs increases up until reaching a plateau after 15 and 20 min for FAV and MLP, respectively. The greenness was assessed on GAPI and found to be in harmony with green analytical chemistry concepts.

Application of Fourier transform-based algorithms to resolve spectral overlapping for UV spectrophotometric co-assay of spiramycin and metronidazole in tablets.

Fourier transform-based algorithms were investigated to resolve UV spectral overlapping of spiramycin and metronidazole in binary mixtures. UV spectra and ratio spectra were both subjected to fast Fourier transform-based first-order differentiation and discrete Fourier transform {i.e. using trigonometric functions such as sin xi - sin (xi + 450), cos xi + cos (xi + 450), sin 2xi - sin 2(xi + 450), cos 2xi + cos 2(xi + 450), sin xi - sin (xi + 600), cos xi + cos (xi + 600)} that followed by 3 passes of 17-point triangular smooth. Such signal transforms generated linear calibration graphs for either drug in the concentration range of 6.25 - 25 mg/L with R2 > 0.990. In comparison with the RP-HPLC reference method, the developed UV spectrophotometric methods had no significant difference in terms of accuracy and precision (p > 0.05) when quantifying spiramycin and metronidazole in their coated tablets. They are suggested as analytical quality control methods for their being environmentally friendly, technically simple, quick and economic.

Eco-Friendly UV Spectrophotometric Method for Evaluation of Marbofloxacin in Tablets: Stability Study.

BACKGROUND: Marbofloxacin (MAR) is an antimicrobial for veterinary use, and it does not have a monograph in an official compendium for the pharmaceutical form in tablets. OBJECTIVE: In this context, the objective of this work was to develop and validate an effective, eco-friendly, and indicative of stability method by spectrophotometry in the ultraviolet region (UV) for quantitative evaluation of MAR in tablets. METHOD: Purified water-ethanol (80:20, v/v) as a diluent, quartz cubette and 296 nm were used. RESULTS: The method was linear in the range of 3-9 µg/mL (0.9994) with detection and quantification limits of 0.39 and 1.18 µg/mL, respectively, selective in the comparison of standard and sample, precise in intraday (RSD 1.20%), interday (RSD 1.68%), and between analysts (RSD 3.26%) levels, exact with average recovery of 100.39% and robust against small changes in wavelength, diluent concentration, and the use of the ultrasound device. The forced degradation test (sample solutions prepared in 0.1 M HCl, 0.1 M NaOH, and neutral conditions and kept at 60°C during 2 h, and exposure to UV 254 nm lamp at ambient temperature during 2 h) showed that the proposed method is able to assess the susceptibility of MAR. CONCLUSIONS: The method can be reliably applied in routine analysis of MAR in tablets as well as being stable, eco-friendly, effective, accessible, and following the principles of green analytical chemistry. HIGHLIGHTS: MAR, an antimicrobial for veterinary use, does not have a monograph in an official compendium for final product evaluation. The use of MAR-based products with inadequate quality can leave residues in foods of animal origin and can also contribute to microbial resistance. So, an ecologically correct and reliable method was developed to evaluate MAR in a final product.