Determination of antazoline and tetrahydrozoline in ophthalmic solutions by capillary electrophoresis and stability-indicating HPLC methods

Novel Deliberately Sensitive and Selective Tetrahydrozoline Voltammetric Sensors Integrated with a Copper Oxide Nanoparticle/Zeolite Platform

The present study introduced a novel disposable screen-printed carbon electrodes (SPCEs) modified with copper oxide/zeolite nanostructures for eco-friendly selective differential pulse voltammetric quantification of tetrahydrozoline (THZ) in eyedrop samples and biological fluids. Modification of the electrode matrix with copper oxide nanoparticles/zeolite nanostructures (CuONPs/ZY) with their effective and synergistic electrocatalytic activity enhanced the electrode performance against electrooxidation of THZ at 0.960 V in BR at pH 9.0 with a diffusion-controlled reaction mechanism. The tentative oxidation mechanism based on molecular orbital calculations postulates the oxidation of THZ molecules through oxidation of a nitrogen atom five-membered ring and the participation of two electrons/protons in the electrode reaction. Linear calibration curves were illustrated within a wide THZ concentration range from 0.24 to 57.2 μg mL-1 recording a limit of detection (LOD) value of 0.0799 μg mL-1. The CuONPs/ZY/SPEs exhibited improved performance compared with the sole reported THZ sensor-based gold film-plated carbon paste electrodes, in addition to their high reproducibility of fabrication and measurement and prolonged shelf lifetime. Tetrahydrozoline was successfully assayed in the presence of excipients, degradation products, and chloramphenicol. The presented voltammetric sensor can be considered as an eco-friendly and reliable analytical approach for monitoring THZ residues in eye drop samples and biological fluids with high recovery compared with the official pharmacopeial analytical protocol. The presented sensors were assessed according to an EcoScale tool and also compared with the reported THZ sensor.

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.

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.

The Development of Spectrophotometric and Validated Stability- Indicating RP-HPLC Methods for Simultaneous Determination of Ephedrine HCL, Naphazoline HCL, Antazoline HCL, and Chlorobutanol in Pharmaceutical Pomade Form

BACKGROUND

Allergic rhinitis, acute nasal congestion and sinusitis are one of the most common health problems and have a major effect on the quality of life. Several medications are used to improve the symptoms of such diseases in humans. Pharmaceutical pomade form containing Ephedrine (EPD) HCl, Naphazoline (NPZ) HCl, Antazoline (ANT) HCl, and Chlorobutanol (CLO) is one of them.

OBJECTIVE

For these reasons, this study includes the development of spectrophotometric and chromatographic methods for the determination of EPD HCl, NPZ HCl, ANT HCl, and CLO active agents in the pharmaceutical pomade.

METHOD

In the spectrophotometric method, third-order derivative of the amplitudes at 218 nm n=5 and the first-order derivative of the amplitudes 254 nm n=13 was selected for the determination of EPD, ANT, respectively while NPZ was determined by the second derivative at 234 nm and n=21. Colorimetric detection was applied for assay analysis of CLO at 540 nm. Furthermore, a reverse phase high performance liquid chromatographic (RP- HPLC) method has been developed and optimized by using Agilent Zorbax Eclipse XDB C18 (75 mm x 3.0 mm, 3.5μm) column. The column temperature was 40°C, binary gradient elution was used and the mobile phase consisted of 15 mM phosphate buffer in distilled water (pH 3.0) and methanol, and the flow rate was 0.6 mL min^-1 and the UV detector was detected at 210 nm. The linear operating range was obtained as 11.97-70, 0.59-3, 2.79-30, and 2.92-200 μg mL^-1 for EPD HCl, NPZ HCl, ANT HCl, and CLO respectively.

RESULTS

The LOD values were found to be 3.95, 0.19, 0.92 and 0.96 μg mL^-1 for EPD HCl, NPZ HCl, ANT HCl, and CLO in the spectrophotometric method, respectively. The linear ranges in the RP-HPLC method were 8.2-24.36 μg mL^-1, 0.083 - 0.75 μg/mL, 2.01-7.5 μg mL^-1 and 2.89-24.4 μg mL^-1 for EPD HCl, NPZ HCl, ANT HCl, and CLO, respectively. The LOD values in the validation studies were 2.7, 0.025, 0.66 and 0.86 μg mL^-1 for EPD HCl, NPZ HCl, ANT HCl, and CLO in RP-HPLC method respectively.

CONCLUSION

The results of the spectrophotometric and chromatographic methods were compared and no differences were found between the two methods.

Clinical implications of mast cell involvement in allergic conjunctivitis

The conjunctiva is a common site for the allergic inflammatory response due to it being highly vascularized, having constant exposure to environmental pollutants and allergenic pollens and having a unique conjunctival associated lymphoid tissue. The primary morbidity of anterior surface conjunctival disorders that include allergic conjunctivitis and tear film disorders is associated with its high frequency of involvement rather than its severity, although the more chronic forms can involve the cornea and lead to sight-threatening conditions. Ocular allergy is associated with IgE-mediated mast cell activation in conjunctival tissue leading to the release of preformed mediators including histamine and proteases and subsequent de novo formation of lipid-derived mediators and cytokines that trigger a cascade of cellular and molecular events leading to extensive migration and infiltration of inflammatory cells to the ocular surface. The trafficking of neutrophils, eosinophils, and lymphocytes to the ocular surface is due to establishing various chemokine gradients (mainly CCL11, CCL24, CCL5, MCP-3, and MCP-4), cell surface expression of adhesion molecules (such as VCAM-1 the ligand for VLA-4), and leukocyte adhesion to vascular endothelium. The release of preformed mediators underlies the acute ocular surface response while the secondary influx of inflammatory cells leading to the recruitment and activation of eosinophils and the subsequent activation of Th2 and Th1 lymphocytes at the level of the conjunctiva reflects the late-phase reaction.