Hydrophilic interaction chromatography (HILIC) for the determination of cetirizine dihydrochloride

Microwave synthesis of blue emissive carbon dots from 5-sulpho anthranilic acid and 1,5-diphenyl carbazide for sensing of levocetirizine and niflumic acid

In this work, water soluble carbon dots (CDs) were synthesized by using 5- sulpho anthranilic acid (SAA) and 1,5-diphenylycarbazide (DPC) as precursors via microwave-assisted method and named as "SD-CDs". We studied the effect of SAA and DPC molar ratio (1:3, 2:2 and 3:1) for the preparation of blue fluorescent CDs, showing the best emission properties at molar 3:1 ratio of SAA and DPC. The as-prepared SD-CDs emit bright blue color under UV light at 365 nm, and exhibit emission peak at 392 nm when excited at 319 nm. The as-synthesized SD-CDs act as a fluorescent sensor for detection of levocetirizine and niflumic acid through the fluorescence "turn-on-off" mechanism. The developed probe exhibited good linearity in the concentrations (levocetirizine - 1.0-100 µM and niflumic acid - 0.5-100 µM) with detection limits of 3.92 nM and 0.19 µM for levocetirizine and niflumic acid, respectively. Importantly, the developed analytical method was successfully used for the detection of levocetirizine in tablets and niflumic acid in biofluids of human (serum, plasma and urine), showing good recoveries from 97 to 99 %. Thus, this SD-CDs-based fluorescence method has the potential for levocetirizine and niflumic acid assays in biological and pharmaceutical samples.

Application of the C-C3N4/Li2CoMn3O8//IL nanocomposite for design a sensitive electrochemical sensor inorder to detection of cetirizine, acetaminophen and phenylephrine in biological and pharmaceuticals samples

Due to the side effects of cetirizine overdose and the need to monitor its concentration in the human body, in this work, an electrochemical sensor has been prepared by utilizing a carbon paste electrode modified with Li₂CoMn₃O₈/CC₃N₄ nanocomposite and ethyl-3-methyl-imidazolium chloride ionic liquid ([EMIM][Cl]) to determine cetirizine in the human blood serum sample and urine as well as drug samples. Li₂CoMn₃O₈/CC₃N₄ nanocomposite was characterized by Fourier transform infrared (FT-IR), field emission scanning electron microscope (FESEM), and X-ray diffraction (XRD) analysis. The investigation of the influence of each modifier component showed that the existence of all components in modification has a synergistic effect. Li₂CoMn₃O₈/CC₃N₄/IL nanocomposite has a larger surface area relative to the components alone, thus providing a more fine-grained media to facilitate electron transfer during the reaction between analyte and electrode. Determination of cetirizine was performed in phosphate buffer solution with pH 7.0 and detection limits obtained in the concentration ranges of 0.03-0.9 and 3-300 μM was 11.8 × 10^-9 M. The diffusion coefficient (D = 9.2 × 10^-6 cm²s^-1) of cetirizine at the surface of the modified electrode was determined by chronoamperometry. Finally, simultaneous detection of cetirizine, phenylephrine and acetaminophen was performed using the suggested sensor without any interference.

Maltose-functionalized HILIC stationary phase silica gel based on self-assembled oligopeptides and its application for the separation of polar compounds

In this study, carbonyldiimidazole was used to bond maltose-modified oligopeptides (Ala-Glu-Ala-Glu-Ala-Lys-Ala-Lys) to the surface of silica spheres for hydrophilic interaction liquid chromatography (HILIC). Attenuated total reflectance-Fourier transform infrared spectroscopy, elemental analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, BET technique, and water contact angle measurement results confirmed the successful immobilization of the obtained material. Compared with the conventional method for preparing carbohydrate stationary phases, this method involves simpler steps and less time-consuming processes. The experimental results proved that the retention mechanism of the maltose-based HILIC column matched the typical HILIC retention mechanism. The column showed high separation efficiency and stability toward the separation of polar compounds such as amino acids, bases, nucleosides, water-soluble vitamins, and salicylic acid and its analogs. The column achieved high selectivity toward oligosaccharide separation. In addition, this efficient analysis demonstrates the applicability of the as-prepared material in the field of food inspection.

Effects of inclusion of cetirizine hydrochloride in β-cyclodextrin

Following the preparation of inclusion complex of cetirizine (CTZ) and β-cyclodextrin (β-CD), the compound was investigated to assess the possibility of modifying the physicochemical properties (solubility, release, stability, permeability) of CTZ after complexation that are vital for subsequent formulation studies involving the said complex. Changes in FT-IR/Raman spectra, DSC thermograms and XRD diffractograms confirmed the formation of a CTZ-β-CD system. Hydrophilic interaction chromatography with a DAD detector was employed to determine alterations of the CTZ concentration during studies following complexation. An analysis of a phase-solubility diagram of c_CTZ = fc_β-CD indicated a linear rise in the solubility of CTZ as the concentration of β-CD increased. The inclusion of CTZ in a system with β-CD significantly reduced the instability of CTZ in the presence of oxidizing factors. It was also found that regardless of the pH of the acceptor fluids used in the release studies an increase was observed in the concentration of CTZ in CD system compared to its free form. The ability to permeate artificial biological membranes manifested by CTZ after complexation was enhanced as well. In summary, CD has significant potential to mask the bitter taste of CTZ and to counter the instability induced by oxidizing factors.