A novel green spectrofluorimetric method for simultaneous determination of antazoline and tetryzoline in their ophthalmic formulation.

A novel spectrofluorimetric method has been developed for determination of antazoline (ANT) and tetryzoline (TET) in their pharmaceutical formulation. A combined application of synchronous spectrofluorimetry and second derivative mathematical treatment was developed. The proposed method depends on reacting the cited drugs with dansyl chloride (DNS-Cl) being a suitable derivatizing agent generating highly fluorescent derivatives measured at emission wavelengths of 703.0 and 642.0 nm after excitation wavelengths of 350.0 and 320.0 nm for ANT and TET, respectively. The joint use of synchronous spectrofluorimetry with second derivative mathematical treatment is for the first time to be developed and optimized in aid of using fluorescence data manager software generating second derivative peak amplitudes at 556.5 nm for ANT and 516.7 nm for TET. Linear responses have been represented over a wide range of concentration (0.5-12.0 µg/mL for ANT and 0.5-10.0 µg/mL for TET). Additionally, statistical comparison of the developed method with the official ones has been carried out where no significant difference was found. Additionally, greenness profile assessment was accomplished by means of four metric tools. Indeed, the method developed is found to be precise, sensitive, and discriminating to assess the cited drugs for regular analysis.

A Novel Spectrofluorimetric Determination of Antazoline and Xylometazoline in their Ophthalmic Formulation; Green Approach and Evaluation.

A green developed spectrofluorimetric method has been applied for Antazoline (ANT) and Xylometazoline (XLO) determination in both pharmaceutical formulation and pure form. The developed method is synchronous spectrofluorimetry coupled with the second derivative mathematical tool for the determination of antazoline and xylometazoline in their dosage form. The developed method depends on reacting the cited drugs with dansyl chloride, a suitable derivatizing agent, to generate highly fluorescent derivatives. The products formed were measured at emission wavelengths; 703.0 and 712.0 nm after being excited at wavelengths; 350.0 and 355.0 nm for antazoline and xylometazoline, respectively. Synchronous spectrofluorimetry coupled with second derivative mathematical tool was developed and optimized using fluorescence data manager software generating second derivative peak amplitudes at 556.5 nm for antazoline and 598.0 nm for xylometazoline. Linear responses have been represented over a wide range of concentration 0.5-12.0 µg/mL for antazoline and 0.1-10.0 µg/mL for xylometazoline, correspondingly. Method validation was successfully applied. Additionally, statistical comparison of developed method with official ones has been carried out where no significant difference was found. Evaluation of the method's greenness was proven using several assessment tools. Indeed, the method developed is found to be precise, sensitive, and discriminating to assess the cited drugs for regular analysis.

Exquisite integration of quality-by-design and green analytical approaches for simultaneous determination of xylometazoline and antazoline in eye drops and rabbit aqueous humor, application to stability study.

This work implements a stability indicating HPLC method developed to simultaneously determine xylometazoline (XYLO) and antazoline (ANT) in their binary mixture, rabbit aqueous humor and cited drug's degradates by applying analytical quality-by-design (AQbD) combined with green analytical chemistry (GAC) experiment for the first time. This integration was designed to maximize efficiency and minimize environmental impacts, as well as energy and solvent consumption. Analytical quality-by-design was applied to achieve our aim starting with evaluation of quality risk and scouting analysis, tracked via five parameters chromatographic screening using Placket-Burman design namely: pH, temperature, organic solvent percentage, flow rate, and wavelength detection. Recognizing the critical method parameters was done followed by optimization employing central composite design and Derringer's desirability toward assess optimum conditions that attained best resolution with satisfactory peak symmetry with short run time. Optimal chromatographic separation was attained by means of an XBridge® C18 (4.6 × 250 mm, 5 µm) column through isocratic elution using a mobile phase consists of phosphate buffer (pH 3.0): ethanol (60:40, by volume) at a 1.6 mL/min flow rate and 230.0 nm UV detection. Linearity acquired over a concentration range of 1.0-100.0 µg/mL and 0.5-100.0 µg/mL for XYLO and ANT, respectively. Furthermore, imperiling cited drugs' stock solutions to stress various conditions and satisfactory peaks of degradation products were obtained indicating that cited drugs are vulnerable to oxidative degradation and basic hydrolysis. Degradates' structures were elucidated using mass spectrometry. Applying various assessment tools; namely: analytical greenness (AGREE), green analytical procedure index (GAPI), analytical eco-scale, and national environmental method index (NEMI), Greenness method's evaluation was applied and proved to be green. In fact, the developed method is established to be perceptive, accurate, and selective to assess cited drugs for routine analysis.

Green TLC-Densitometric Method for Simultaneous Determination of Antazoline and Tetryzoline: Application to Pharmaceutical Formulation and Rabbit Aqueous Humor.

Ophthalmic pharmaceutical preparation containing antazoline (ANT) and tetryzoline (TET) is prescribed widely as an over the counter medication for allergic conjunctivitis treatment. Development of a selective, simple and environmentally friendly thin-layer chromatographic method established to determine both ANT and TET in their pure forms, pharmaceutical formulation and spiked aqueous humor samples. By using silica gel plates and means of a developing system consists of ethyl acetate:ethanol (5:5, by volume), the studied drugs separation was achieved, and scanning was carried out at 220.0 nm for the separated bands with a 0.2-18.0 µg/band concentration range for each of ANT and TET. Standard addition technique application was carried out to determine the proposed method validity. Statistical comparison was made between the proposed method and the official methods ANT and TET showing no significant difference concerning accuracy and precision. Furthermore, greenness profile assessment was accomplished by means of four metric tools, namely, analytical greenness, green analytical procedure index, analytical eco-scale and national environmental method index.Highlights.

Spectrophotometric platform windows' exploitation for the green determination of Alcaftadine in presence of its oxidative degradation product.

This study presents the determination of Alcaftadine (ALF) in its oxidative degradation product presence by applying comprehensive study comparative of four different green stability indicating spectrophotometric approaches through successful exploitation of different spectrophotometric platform windows. Window I; based on absorption spectrum zero order data manipulation using the newly developed extended absorbance difference (EAD). Window II; based on derivative spectra by second order derivative (D2) data manipulation. Window III; based on ratio spectra applying constant multiplication (CM) and absorptivity centering via factorized ratio difference spectrum (ACT-FSRΔP) methods data manipulation. Finally, window IV; based on derivative of ratio spectrum by virtue of first derivative of ratio spectral (DD1) method data manipulation. Calibration curves construction were over linearity range; 1.0-14.0 µg/mL for ALF. The proposed methods accuracy, precision, and linearity range were determined and validated as per ICH guidelines. Moreover, they were able to analyze ALF in raw form, dosage form and in existence of its oxidative degradation product. Statistical comparisons were done between the proposed methods and the reported one showing no significant difference concerning accuracy and precision. Furthermore, greenness profile assessment was accomplished by means of four metric tools; namely: analytical greenness (AGREE), green analytical procedure index (GAPI), analytical eco-scale, and national environmental method index (NEMI).

Novel solid-contact ion-selective electrode based on a polyaniline transducer layer for determination of alcaftadine in biological fluid.

Fabrication of a novel ion selective electrode for determining alcaftadine was achieved. The glassy carbon electrode (GCE) was utilized as a substrate in fabrication of an electrochemical sensor containing polyaniline (PANI) as an ion-to-electron transducer layer. A PVC polymeric matrix and nitrophenyl-octyl-ether were employed in designing the ion-sensing membrane (ISM). Potential stability was improved and minimization of electrical signal drift was achieved for inhibition of water layer formation at the electrode interface. Potential stability was achieved by inclusion of PANI between the electronic substrate and the ion-sensing membrane. The sensor's performance was evaluated following IUPAC recommendations. The sensor dynamic linear range was from 1.0 × 10-2 to 1.0 × 10-6 mol L-1 and it had a 6.3 × 10-7 mol L-1 detection limit. The selectivity and capabilities of the formed alcaftadine sensor were tested in the presence of its pharmaceutical formulation excipients as well as its degradation products. Additionally, the sensor was capable of quantifying the studied drug in a rabbit aqueous humor. Method's greenness profile was evaluated by the means of Analytical Greenness (AGREE) metric assessment tool.

Forced Degradation Studies and Development and Validation of HPLC-UV Method for the Analysis of Velpatasvir Copovidone Solid Dispersion.

Analytical methods for the drug substance and degradation products (DPs) are validated by performing forced degradation studies. Forced degradation studies of Velpatasvir (VEL) drug substance and Velpatasvir copovidone solid dispersion (VEL-CSD) were performed under the stressed alkaline, acidic, oxidative and thermal conditions according to ICH guidelines ICH Q1A (R2). VEL is labile to degrade in stressed alkaline, acidic, and oxidative conditions. It is also photolabile and degraded during photostability studies as described by ICH Q1B, and showed no degradation on exposure to extreme temperature when protected from light. A sensitive stability indicating HPLC-UV method was developed and validated for the separation of VEL and eight DPs. The DPs of VEL are separated using gradient elution of mobile phase containing 0.05% Trifluoroacetic acid (TFA) and methanol over symmetry analytical column C18 (250 mm × 4.6 mm, 5 µm) with a flow rate of 0.8 mL min-1. Simultaneous detection of all DPs and VEL was performed on UV detector at 305 nm. The performance parameters like precision, specificity and linearity of the method were validated using reference standards as prescribed by ICHQ2 (R1). Limits of quantification and limits of detection were determined from calibration curve using the expression 10δ/slope and 3δ/slope respectively. The proposed method is stability-indicating and effectively applied to the analysis of process impurities and DPs in VEL drug substance and VEL-CSD.

Sticking - pulling strategy for assessment of combined medicine for management of tough symptoms in COVID-19 Pandemic using different windows of spectrophotometric Platform-Counterfeit products' detection.

This study presents a comprehensive comparative study of different green spectrophotometric approaches without any physical separation on processing a ternary mixture of Aceclofenac (ACE), Paracetamol (PAR) and Rabeprazole (RAB) in combined medicine for managing tough symptoms in the COVID-19 Pandemic. The different univariate complementary resolutions according to the response used for the assay of the cited drugs after applying the processing steps were implemented using successive in-silico sample enrichment for resolving the ternary mixture via different windows of spectrophotometric platform using sticking - pulling strategy (SPS). Window I; based on manipulation of the data of zero order absorption spectrum of the mixture using novel Extended absorbance difference (EAD) and Absorbance difference (AD) methods coupled with corresponding spectrum subtraction method (SS). Window III; based on manipulation of the data of ratio spectra via Constant value coupled with constant subtraction (CV-CS) and novel Induced dual amplitude difference (IDAD) method coupled with corresponding spectrum subtraction method (SS). Finally, window IV; based on manipulation of the data of derivative of the ratio spectrum of the mixture via novel Factorized derivative ratio null contribution (FDD-NC) and Factorized unlimited derivative ratio (FUDD) methods coupled with corresponding spectrum subtraction method (SS). Synthetic mixtures and commercial medicine were constructively analyzed using the proposed methods while maintaining calibration graphs to be linear over ranges; 4.0-40.0 µg/mL for ACE, 2.0-14.0 µg/mL for PAR and 4.0-30.0 µg/mL for RAB. Moreover, methods' validation was confirmed via performing exhaustive statistical treatment of the experimental findings. The proposed methodologies can be used for the routine analysis of the cited drugs in quality control laboratories. Additionally, Spectral Similarity Index (SSI) was calculated to detect counterfeit products and methods' greenness profile was finally guaranteed through analytical greenness (AGREE) metric assessment tool.

Evaluation of in silico and in lab sample enrichment techniques for the assessment of challengeable quaternary combination in critical ratio.

A comparative study of successive spectrophotometric resolution technique for the simultaneous determination of a challengeable quaternary mixture of Chlorpheniramine maleate (CPM), Pseudoephedrine hydrochloride (PSE), Ibuprofen (IBU) and Caffeine (CAF) is presented, without preliminary physical separation steps. Several successive steps were applied on built-in spectrophotometer software utilizing zero and/or derivative and/or ratio spectra of the studied components. These methods, namely, Dual amplitude difference (DAD) as a novel method, Constant multiplication coupled with spectrum subtraction method (CM-SS), Factorized first derivative coupled with derivative transformation method (FD1 -DT) and Derivative ratio method (DD1). The calibration graphs are linear over the concentration range of 10.0-80.0 µg/mL,150.0-900.0 µg/mL, 200.0-1400.0 µg/mL and 3.0-30.0 µg/mL for CPM, PSE, IBU and CAF, respectively. The specificity of suggested methods was studied via laboratory prepared (diverse ratios) mixtures and were successfully applied for Antiflu® capsules' analysis. Moreover, sample enrichment via In Silico (via software of spectrophotometer) and In Lab (via spiking with pure sample) techniques was elected for a pharmaceutical dosage form analysis comprising CPM and PSE as minor components. Accuracy, precision and specificity were between the valid limits. Validation steps were done in accordance with the ICH guidelines. Moreover, statistical comparison was carried out between the obtained and reported results for pure powder form and no significant difference appeared.

Synchronous UPLC Resolution of Aceclofenac and Diacerin in Their Powdered Forms and Matrix Formulation: Stability Study.

Accurate, rapid and selective reversed phase ultra-performance liquid chromatography method with UV detection has been established and validated for the synchronous determination of aceclofenac (ACE) and diacerin (DIA) in the occurrence of diclofenac sodium and rhein, their main degradation products, respectively. Chromatographic separation was accomplished using Inertsil C-18 column (50 × 2.1 mm i.d., 1.7 µm particle size) in isocratic mode, with mobile phase consisting of 20 mM ammonium acetate buffer:acetonitrile in the ratio of 42:58 (v/v), pH adjusted to 3.00 by using 10% acetic acid, the flow rate of 0.25 mL/min and UV detection was performed at 265 nm. The retention times were 2.00 +/- 0.24, 2.69 +/- 0.19, 4.00 +/- 0.23 and 5.24 +/- 0.25 min for DIA, rhein, ACE and diclofenac sodium, respectively. Excellent linearity was shown over a range of 1.0-150.0 µg/mL and 0.5-87.5 µg/mL with mean percentage recoveries of 98.87 ± 1.19 and 98.84 ± 1.08 for ACE and DIA, respectively. Parameters of precision and accuracy of the method meet the established criteria. The obtained RSD values were quite low and indicate good reproducibility of the method. Thus, the developed method can be used for the combined dosage form analysis and its chemical stability studies.

Smart Spectral Processing of Data for the estimation of Commonly Used Over-the-counter (OTC) Co-formulated drug; Pseudoephedrine hydrochloride and Ibuprofen.

Oral pharmaceutical preparation containing pseudoephedrine hydrochloride (PSE) and ibuprofen (IBU) is widely prescribed as over- the- counter (OTC) for treatment of common cold-sinus. Development of four precise and accurate spectrophotometric methods are established for the concurrent determination of (PSE) and (IBU)in this preparation exploiting zero and/or ratio spectra. Method I is a dual wavelength method (DW). method II is a ratio difference method (RD), method III is a constant multiplication coupled with spectrum subtraction method (CM-SS) and method IV is a constant center coupled with spectrum subtraction method (CC-SS). While, absorbance correction method (AC) is successfully established for the determination of (IBU) only exploiting zero order absorption spectra. The calibration curves are linear over the concentration range of 100.0-900.0 µg/mL for (PSE) and 200.0-1000.0 µg/mL for (IBU). No separation steps are required for the spectrophotometric procedures which augments their simplicity. Analyzing synthetic mixtures of the cited drugs evaluated the specificity of the applied methods. Validation of the analysis results have been statistically performed confirming the accuracy and reproducibility of the proposed method through recovery studies which were carried out by following ICH guidelines. Thus, the developed methods can be successfully applied routinely in quality control laboratory.