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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.

In this study, a simple, fully validated and rapid reversed-phase HPLC with photodiode array detector method was developed for the simultaneous determination of 11 selected phenolic antioxidants over 33 min in personal care and food samples containing extracts of green apple, pomegranate (Ponica granatum) and argan oil (Argania spinosa). The method was performed using NUCLEODUR C18 column 5 µm particle size and 12.5 cm length. The HPLC mobile phase was prepared as follows, solution A: 1% aqueous acetic acid and solution B: Acetonitrile. The method was gradient at flow rate 1.0 mL/min with a simple mobile phase, minimal sample preparation, and diminished organic solvent usage (3% acetonitrile for almost 90% of the run time). The detection was carried out at 278 nm. The method presented good precision and accuracy with RSD% values ranged between 0.33 and 1.94% and wide linear range. The developed method was successfully applied on 67 personal care and food products present in Egyptian market and can be used for routine screening in laboratory for the regular quality control of the antioxidant content for products containing the mentioned extracts.

A rapid, sensitive, and eco-friendly micellar high-performance thin-layer chromatography (HPTLC) technique for the simultaneous analysis of cefoperazone and sulbactam in pure and vial pharmaceutical formulation was developed. Merck aluminum HPTLC plates covered with silica gel 60 F254 were used as the stationary phase; acetone‒ethanol‒ethyl acetate‒2% sodium dodecyl sulfate‒glacial acetic acid (3:2:4:1:0.5, V/V) were used as the mobile phase. This chromatographic system results in symmetric, compact peaks at RF values of (0.45 ± 0.015) and (0.69 ± 0.008) for cefoperazone and sulbactam, respectively. Densitometric scanning of the separated spots was done at 265 nm. The proposed method can quantitatively analyze cefoperazone and sulbactam in their laboratory prepared combinations and vials pharmaceutical formulation. The environmental greenness of the proposed HPTLC method was successfully assessed by the new green analytical procedure index. The method is considered to be a green eco-friendly HPTLC method because of its usage to green solvents, minimal waste production, and short time of analysis. The proposed method can also be helpful in the routine quality control analysis of the studied medications.

Implementing green analytical techniques has been one of the main objectives of the analytical chemistry community for the past two decades. The aim of transitioning to green analytical chemistry is to establish new methods environmentally benign instead of traditional methods. According to WHO, 20 million people worldwide are affected by schizophrenia, and 45 million people worldwide are affected by bipolar disorders. For that, in this work we develop a green HPTLC method to quantify simultaneously the four antipsychotics chloropromazine HCl, asenapine maleate, quetiapine fumarate and aripiprazole in pure form and tablet formulations. In this chromatographic method, separation was performed using silica gel 60 F254 HPTLC plates, the mobile phase composed of binary mixture of green solvents (ethanol : water (9 : 1 v/v)) which gave compact band with Rf values ranged between 0.14 to 0.70 for the drugs. The method was validated for linearity, accuracy, precision, selectivity and robustness according to ICH guidelines. It was assessed for greenness by analytical Eco-scale and compared with reported HPTLC methods for single analysis of these antipsychotics.

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.

Vildagliptin is a selective, potent drug developed for the treatment of type 2 diabetes mellitus. Lower limb infections in diabetic patients are frequently caused by a mixture of aerobic and anaerobic pathogens which needs the co-administration of antimicrobial agents such as β-lactam/β-lactamase inhibitor combinations and metronidazole for anaerobic pathogens. In the present study, a new gradient HPLC method was developed for the simultaneous separation and quantification of Vildagliptin, Ampicillin, Sulbactam and Metronidazole in pharmaceutical dosage forms and human urine. Chromatographic separation was achieved on Kinetex 2.6 C18 column 100A (4.6 mm × 10 mm) with UV detection at 230 nm. The separation time was about 5 min which allows diminished organic solvent consumption. The method conditions were optimized with respect to different factors. The method was found to be linear, specific, precise and accurate and was compared with other reported methods for single determination of these drugs using student’s t test and F test. The method has the advantage of being rapid, sensitive and also its application to human urine gives the advantage to be used in clinical units for hospitalized patients. This method was used to know the patterns of urinary excretion of Vildagliptin, Ampicillin-sulbactam and Metronidazole by healthy volunteers.

In this study, a Quick, Easy, Cheap, Effective, Rugged and Safe method (QuEChERS) method was optimised to extract 30 pesticides which are the most used in Egypt in soil and drainage water. Optimisation was performed by Experimental Design expert 7.1 to get better recoveries. The procedure combined with a developed GC-MS for determination of these pesticides. Total analysis time was 36 min with 1 ml injection volume. The limit of quantification (LOQ) was ranged between 4.59 ng/ml, and 15.91 ng/ml for all pesticides. Most standard deviations were in the range between 0.41 and 1.41 indicating satisfactory accuracy. The validated method was applied to Egyptian soil and drainage water samples brought from different places in Damietta city. Dimethoate, β-Endosulfan, DDD, Malathion, Vinclozolin, DDT, Endrin, Cyprodinil, Primiphos ethyl, Tetradifon, Parathion ethyl and Diazinon were detected and quantified. So risk assessment on human health should be considered especially for those pesticides.

A rapid method for the quantification of levetiracetam (LV) in human urine using high-performance liquid chromatography combined with UV detection (HPLC–UV) was developed and validated for linearity, repeatability, limit of detection, and limit of quantitation. In addition, a high-performance liquid chromatography combined with electrospray ionization mass spectrometry was described for its identification in human urine. Chromatographic separation was achieved on 250 × 4.6 mm (i.d.) Discovery® (5 µm particle size) reversed-phase C18 analytical column using 0.1% formic acid in water–acetonitrile, in ratio of 85:15, v/v as mobile phase and UV detection at 210 nm for the HPLC–UV method and using 0.1% formic acid in water–acetonitrile, in ratio of 75:25, v/v as mobile phase for LC-ESI-MS method. The HPLC–UV method was successfully applied for establishment of the urinary excretion pattern of LV after oral dose.

Three methods for the simultaneous determination of two multicomponent mixtures containing phenobarbitone and ephedrine hydrochloride with theophylline, and postafene hydrochloride [mix 1]; or dihydroxypropyltheophylline and chlorpheniramine maleate [mix 2] were proposed. The HPLC method depended on the use of gradient mobile phase system consisting of (A) acetonitrile and (B)12 mM ammonium acetate; pH 4.5 with cyanopropyl column at a flow rate of 1.5 mL min−1. Quantitation was achieved with UV detection at 215 nm, based on peak area. The two other methods were multivariate spectrophotometric calibration methods: partial least squares (PLS-1) and principal component regression (PCR). These approaches were successfully applied to quantify each component in the mixture. Analytical figures of merit (FOM) were calculated for both PLS-1 and PCR. The proposed methods were successfully applied for the analysis of pharmaceutical formulations containing the two multicomponent combinations and the results were comp...

Chemometric-assisted spectrophotometric methods and high performance liquid chromatography (HPLC) were developed for the simultaneous determination of the seven most commonly prescribed β-blockers (atenolol, sotalol, metoprolol, bisoprolol, propranolol, carvedilol and nebivolol). Principal component regression PCR, partial least square PLS and PLS with previous wavelength selection by genetic algorithm (GA-PLS) were used for chemometric analysis of spectral data of these drugs. The compositions of the mixtures used in the calibration set were varied to cover the linearity ranges 0.7-10 μg ml(-1) for AT, 1-15 μg ml(-1) for ST, 1-15 μg ml(-1) for MT, 0.3-5 μg ml(-1) for BS, 0.1-3 μg ml(-1) for PR, 0.1-3 μg ml(-1) for CV and 0.7-5 μg ml(-1) for NB. The analytical performances of these chemometric methods were characterized by relative prediction errors and were compared with each other. GA-PLS showed superiority over the other applied multivariate methods due to the wavelength selection. A new gradient HPLC method had been developed using statistical experimental design. Optimum conditions of separation were determined with the aid of central composite design. The developed HPLC method was found to be linear in the range of 0.2-20 μg ml(-1) for AT, 0.2-20 μg ml(-1) for ST, 0.1-15 μg ml(-1) for MT, 0.1-15 μg ml(-1) for BS, 0.1-13 μg ml(-1) for PR, 0.1-13 μg ml(-1) for CV and 0.4-20 μg ml(-1) for NB. No significant difference between the results of the proposed GA-PLS and HPLC methods with respect to accuracy and precision. The proposed analytical methods did not show any interference of the excipients when applied to pharmaceutical products.