Determination of trimebutine in pharmaceuticals by differential pulse voltammetry at a glassy carbon electrode

Utility of Cilefa Pink B, a food dye in a facile decoration of the first green molecular-size-based fluorescence probe (MSBFP) for determining trimebutine; application to bulk, dosage forms, and real plasma

This research presents the first novel green molecular-size-based fluorescence probe (MSBFP) as a spectroscopic strategy for detecting the Trimebutine drug. The method used a green, one-pot, direct spectrofluorimetric methodology to validate and assess the medication. Trimebutine drug and Cilefa Pink B formed an immediate ultra-fluorescent complex when mixed in an acidic environment. The fluorimetric study relied on Trimebutine's amplification of the dye response, which correlated to the generated complex's molecular size at 361 nm. Upon complexation, the molecular mass has grown from 504.5 to 1384.4 g mol^-1. This growth is proportionally coupled to the drug concentration range of 0.035-1.5 µg mL^-1. The lower and upper limits of the sensitivity varied from 0.010 and 0.029 µg mL^-1, respectively. Trimebutine-Cilefa Pink B complexes were analyzed to determine optimal values for all the tunable system variables. Also, The International Council for Harmonization (ICH) requirements were successfully met by the system. In addition, this method effectively retrieved the drug in the intended pharmaceutical dosages. A significant achievement was using the developed fluorimetric method to monitor the drug of interest in human biofluids. The environmental friendliness of the planned procedure was then evaluated.

Green conventional and first-order derivative fluorimetry methods for determination of trimebutine and its degradation product (eudesmic acid). Emphasis on the solvent and pH effects on their emission spectral properties

In this report, the fluorescence properties of the antimuscarinic drug trimebutine maleate (TRB) were fully studied and characterized. TRB exhibited intrinsic fluorescence that is greatly dependent on the local environmental factors including the solvent nature and the pH. Yet, its fluorescence was not significantly influenced by the existence of some surface active agents and polymer. The outcomes of this investigation verified that TRB fluorescence emission is intense in ethanol: 1.0 M aqueous acetic acid (9:1, v/v) with emission maxima at 357 nm and excitation maxima at 270 nm. Whereas, going towards higher pH causes fluorescence quenching. These conditions permitted ultrasensitive fluorimetric determination of TRB over the concentration range of 2.00-1500.0 ng/mL with a lower detection limit of 0.40ng/mL Application for the determination of TRB in tablets, ampoule and suspension was successfully achieved with %recoveries ranged between 98.21-100.17%. Furthermore, a first order derivative fluorimetric method was validated for resolving and simultaneous determination of TRB and its degradation product and impurity, eudesmic acid (EUA) making use of the pH-mediated fluorescence spectral shift of EUA. An ethanolic solution containing acetate buffer (pH 5.3) was used for this goal with excitation at 255 nm and measurement of the first order derivative peak amplitudes at respective zero-crossing points of 375 and 351 nm over the corresponding concentration ranges of 20.00-500.00 and 10.00-300.00 ng/mL for TRB and EUA, respectively. The two methods were assessed regarding greenness and eco-friendship by the National Environmental Methods Index and analytical eco-scale score approaches which confirmed their excellent greenness and safety.

Different aspects in manipulating overlapped spectra used for the analysis of trimebutine maleate and structure elucidation of its degradation products

Background

Four rapid, accurate, and validated stability-indicating spectrophotometric methods have been described in the present work for the analysis of trimebutine maleate (TM) in existence of its degradation products in its authentic form and in pharmaceutical formulations excluding any separation steps.

Results

These methods were a dual-wavelength (DW) method which allows the determination of TM in existence of its degradation products at 243 nm and 269 nm, second derivative (D2) method measured at peak amplitude at 268 nm, ratio difference (RD) method at 242 nm and 278 nm, and constant center coupled with spectrum subtraction (CC-SS) method at 242 nm and 278 nm versus 278 nm. By applying the suggested methods, TM could be quantified in the range of 5.0–60.0 μg/mL with percentage recoveries 99.97 ± 0.40, 100.36 ± 0.58, 99.90 ± 0.42, and 100.15 ± 0.45 for DW, D2, RD, and CC-SS methods, respectively. International Conference on Harmonization guidelines were followed for validation of the described methods, and the application of laboratory-prepared mixtures along with different pharmaceutical drugs including the target drug showed favorable results without any contribution from additives.

Conclusions

Statistical comparison was used to compare the proposed and official methods, and satisfactory results for both accuracy and precision were obtained. The results confirm the applicability of the suggested methods for the determination of TM in quality control laboratories.