Development of Advanced Chemometric-Assisted Spectrophotometric Methods for the Determination of Cromolyn Sodium and Its Alkaline Degradation Products

Analytical Methods for Furanochromone Natural Product, Khellin and Its Inspired Drug Candidates, Amiodarone and Sodium Cromoglycate

Khellin is the key furanocoumarin of Ammi visnaga L. (Lam.) that exhibits various biological properties. This unique natural product has inspired the discovery of two first-in-class drugs, amiodarone and sodium cromoglycate. A wide range of analytical methods were generated while translating khellin scaffold into clinically used drugs; however, they have never been reviewed and critically assessed. The present review aims to review and evaluate the analytical techniques for the natural products, khellin, visnagin, and their inspired drugs, amiodarone and sodium cromoglycate. High-performance liquid chromatography (HPLC) is the extensively used technique in most analytical methods reported for these compounds; however, other techniques including the fluorimetry, luminescence spectrophotometry, potentiometry, voltammetry, FT-Raman spectroscopy, and ELISA were also employed. The review will be helpful for further basic and translational research on furanochromone and related scaffolds.

Development and Validation of a Liquid Chromatography-Mass Spectrometry Assay for Determination of Cromolyn Sodium in Skin Permeation Studies

Cromolyn sodium (CS) is a mast cell stabilizer administered to treat allergic diseases. A topical system would sustain its delivery and may be designed for treatment of atopic dermatitis. Established HPLC protocols for detection of CS are time consuming and intensive, indicating the need for a more streamlined method. This study aimed at developing and validating a sensitive and selective LC-MS method for quantifying CS in skin permeation studies that was less time and resource demanding. The optimized method involved an isocratic mobile phase (10 mM NH₄HCO₃, pH 8.0, 90% and ACN, 10%) at a flow rate of 0.25 mL/min. Detection involved direct MS/MS channels with m/z 467.0255 (precursor) and m/z 379.0517 (fragment) using argon as the collision gas. CS calibrants were prepared in PBS, pH 7.4, and methanol for validation (0.1-2.5 μg/mL). To ensure no skin interference, dermatomed porcine skin was mounted on Franz diffusion cells that were analyzed after 24 h. The skin layers were also separated, extracted in methanol, and analyzed using the developed method. Retention time was 1.9 min and 4.1 min in methanol and buffer, respectively. No interfering peaks were observed from the receptor and skin extracts, and linearity was established between 0.1 and 2.5 μg/mL. Interday and intraday accuracy and precision were within the acceptable limit of ±20% at the LLOQ and ±15% at other concentrations. Overall, the simplified, validated method showed sensitivity in detecting CS in skin without interference and was applied to demonstrate quantification of drug in skin following 4% cromolyn sodium gel exposure.

Utilization of N,S-Doped Carbon Dots as a Fluorescent Nanosensor for Determination of Cromolyn Based on Inner Filter Effect; Application to Aqueous Humor

A simple and eco-friendly hydrothermal technique is used to prepare water soluble N and S co-doped carbon quantum dots probe (N,S-CQDs) from thiosemicarbazide and citric acid. Several characterization techniques were performed in order to ensure well- synthesis of highly luminescent N,S-CQDs. The prepared probe exhibited analytical potential as optical nanosensor for the spectrofluorimetric determination of cromolyn sodium (CRO) in its pharmaceutical dosage forms and aqueous humor. The emission intensity of the synthesized N,S-CQDs was measured at 411 nm after excitation at 345 nm. Addition of increasing concentrations of CRO to N,S-CQDs led to quenching of its fluorescence intensity. CRO was investigated within wide concentration range of 10.0 to 150.0 μM with limit of detection of 2.0 μM and limit of quantification of 6.0 μM. The quenching of fluorescent N,S-CQDs occurs through inner filter effect (IFE). The developed spectrofluorimetric method was successfully optimized and validated according to International Council of Harmonization (ICH). Method greenness is proved through using both Eco-scale and AGREE approaches.