The convenient use of fluorescamine for spectrofluorimetric determination of midodrine hydrochloride in pure form and its tablets formulation: Application to content uniformity testing

Facile Integration of Hanztsch's Switch-Off/On Modeled Fluorogenic Probe for Feasible Tagging and Tracking of the Midodrine Drug in Different Matrices; First Evaluation of the Method's Greenness, Whiteness, Blueness, Quantum Yield, and Tablets' Content Homogeneity

The proposed investigation follows a certain methodology to guarantee that the procedure employed is sustainable and green. It is noteworthy to mention that various tools have been implemented as potential indicators of environmental sustainability (greenness and whiteness). From a novelty viewpoint, a new tool, BAGI, for the method's blueness evaluation was applied to the planned method and showed a high applicability score. Fortunately, the WAC concept, which combines ecological and functional variables using the Green/Red/Blue design (RBG 12 tool), identifies the established analytical approach as white. In the planned study, a new, green, simple, nano-trace-sensitive, original fluorimetric methodology was established to analyze and assess midodrine hydrochloride content in different matrices. Midodrine's primary amine moiety reacts with Diacetylmethane/Oxymethylene reagent in an acetate buffer, which leads to generating a fluorescent dihydrolutidine derivative (Hantzsch-named reaction). Consequently, the signal strength of this compound was quantified at 487 nm, with an excitation wavelength of 426 nm. This analysis indicated that the technique exhibited linearity within the range of 0.05 to 1.1 µg mL-1 concentrations, accompanied by remarkably good sensitivity values (LOD and LOQ). The methodology employed in this examination was subjected to validation following the rules recognized by ICH. From the perspective of pharmacy and chemistry, the method presented in this study was successfully employed to analyze commercially available tablets, oral drops, and human fluids. The outcomes obtained demonstrated satisfactory recovery rates without any interference from excipients. Following the USP recommendations, the intended technique was finally implemented to explore the content homogeneity evaluation.

Utility of dansyl chloride for the establishment of a sensitive spectrofluorimetric approach for estimating midodrine hydrochloride: application to content uniformity testing

A new, straightforward spectrofluorimetric approach with high sensitivity was established for determining midodrine hydrochloride based on derivatizing this drug through its reaction with 5-(dimethylamino)naphthalene-1-sulfonyl chloride (dansyl chloride). The highly fluorescent product was extracted with methylene chloride, and then its emission was measured at 532 nm after excitation at 339 nm. The reaction was conducted in aqueous medium containing 0.1 M borate buffer (pH 8.2). The results showed that the proposed method is sensitive with high linearity in the range from 0.1 to 3 μg mL-1. The lower limits of detection and quantitation were 29 and 88 ng mL-1, respectively. Furthermore, the proposed approach was analytically assessed by applying the ICH guidelines. The suggested approach was effectively utilized for the estimation of the medicine in its marketable tablet formulations with excellent recovery and without any interfering effect from excipients. Moreover, the presented approach was utilized to test the content uniformity of commercial tablets following the USP guidelines.

Salvage Parenteral Antibiotics for Multidrug-Resistant (MDR) Gram-Negative Bacteria; A Fluorescamine-Based Technique for Ultrasensitive Spectrofluorimetric Measurement of Polymyxins; Human Plasma Application

Polymyxins (PMS), namely Colistin (CS) and Polymyxin B (Poly B), are antimicrobial drugs that recently used to treat multi-resistant gram-negative bacteria infections and their resurgence owing to a lack of new antibiotics. A speedy, simple, and ultrasensitive spectrofluorimetric screening of PMS in pharmaceutical formulations and biological fluids was urgently required from this point forward. A reaction between fluorescamine and the aliphatic amino moiety found in both drugs was performed in a slightly alkaline borate buffer (pH 8.5) resulted in highly fluorescent products measured at λ_em 460 (after λ_ex 390.5 nm). Linear calibration curves were constructed over the concentration range of 70 to 1800 ng mL^-1 and 100 to 1400 ng mL^-1 , with slope values of 0.273 and 0.286, correlation coefficients of 0.9998 and 0.9997, and determination coefficient of 0.9997 and 0.9994 for Poly B and CS, respectively. The ultra sensitivity of the proposed method was demonstrated by the very low limits of quantifications values of 67.56 ng mL^-1 and 94.89 ng mL^-1 for Poly B and CS, respectively. The cited drugs were successfully determined in their intravenous market preparations by the prescribed method. Moreover, due to the high sensitivity, the suggested method was employed to assay the investigated drugs in biological fluids.