Exploring fluorescence of metal nanoparticles for effective utility in drug sensing: A Promising ''on-off'' fluorescence probe for analysis of cephalosporins is fabricated.

A promising fluorescent nano sensor was fabricated exploiting the unique optical and physicochemical properties of silver nanoparticles (AgNPs). AgNPs were prepared following a chemical reduction technique to get a highly water-soluble nano sensor, stable for at least 1 month without the need of organic stabilizers. Full characterization of AgNPs was done using different spectroscopic and microscopic techniques. They exhibit excellent water solubility, physicochemical and optical properties, enabling them to be successfully applied in chemical sensing of drugs. The prepared AgNPs could be conceived as a fluorescent probe for the fluorimetric determination of two commonly administered cephalosporins ceftriaxone (CTX) and cefepime (CFP) based on the quenching behavior of the fluorescence omitting the need for pre-derivatization or chromogenic reagents. The fluorescence intensity of AgNPs at 485 nm after excitation at 242 nm was quantitively quenched upon increasingly adding the studied drugs over the concentration ranges of 1-10 µg/mL and 0.9-9 µg/mL with detection limits of 0.178 µg/mL and 0.145 µg/mL for CTX and CFP, respectively. The quenching mechanisms were investigated and illustrated. The influence of different experimental parameters was studied and optimized. The suggested sensor provides an innovative, sensitive, and eco-friendly approach for the assay of the drugs in their pharmaceutical vials and quality control laboratories with excellent % recoveries of 99.88 ± 1.15, 99.95 ± 1.15 for CTX and CFP, respectively. The method was validated in accordance with ICH Q2 R1 recommendations. The greenness evaluation was performed through both Eco-Scale and GAPI revealing the green criteria of the developed method.

Novel approaches of erythrosine B as a food dye-derived spectroscopic probe for assessing trospium chloride in raw material and dosage form.

Two facile spectroscopic methodologies were designed for estimating trospium chloride (TPM) in raw material and tablets with high operational reliability and selectivity. The methods were based on using erythrosine B (EB) as a spectroscopic tool for ion-pair complex formation with the drug. In a mild acidic medium of Britton Robinson buffer (pH 4.0), the ionized hydroxyl group in the reagent interacted with the ionized amine in the studied drug. Method I was based on the spectrophotometric measuring of the absorbance of the reaction product at 557 nm. Method II was based on spectrofluorimetric measurement of the quenching effect of TPM on the inherent fluorescence of EB at 550 nm (λex. = 528 nm). The two methods showed linearity through ranges 1.0-10.0 and 0.5-10.0 µg/ml for Methods I and II, respectively. The suggested methods were exploited for analyzing TPM in Trospamexin® tablets and showed good applicability. The designed systems were validated as per International Conference on Harmonization guidelines. Experimental conditions were modulated to obtain the best sensitivities. The quenching mechanism was investigated and the quenching constant was computed relying on the Stern-Volmer equation. Environmental impact was appraised using novel metric green tools, GABI, and AGREE. The suggested systems excelled over other reported methods in terms of greenness, sensitivity, and cost-effectiveness.

Implementation of HILIC-UV technique for the determination of moxifloxacin and fluconazole in raw materials and pharmaceutical eye gel.

Hydrophilic interaction liquid chromatography (HILIC) has inherent merits over RP-HPLC in the analyzing of hydrophilic substances. Accordingly, an innovative HILIC-UV methodology is proposed for the simultaneous estimation of ethyl paraben (PRN), fluconazole (FLZ) and moxifloxacin hydrochloride (MOX) in raw materials and pharmaceutical eye gel. The separation process was conducted using Waters XBridge™ HILIC column (100 mm × 4.6 mm, 3.5 µm particle size) at room temperature. Isocratic mobile phase containing acetonitrile: 0.1% triethylamine buffer (90:10, v/v, pH 5.0), was pumped at flow rate 1.0 mL/min and detected at 260 nm. Under these optimized conditions, PRN, FLZ and MOX showed rectilinear relationships with the concentration ranges (0.5-6.0), (5.0-50.0) and (5.0-60.0) µg/mL, respectively. The developed method offered at least fivefold increase in sensitivity within shorter time than the reported methods. Three greenness assessment tools namely: Analytical eco-scale, GAPI and AGREE were exploited to investigate the method's impact on the environment and conduct a comparative study with the reported methods. International council of Harmonization (ICH) guidelines have been followed to calculate validation parameters. The statistical comparison between results of the suggested method and the comparison method showed no discrepancy confirming accuracy of the method.