Eco-Friendly Pharmaceutical Analysis of Rifaximin in Tablets by HPLC-MS and Microbiological Turbidimetry

Green Method for Evaluation of Marbofloxacin Tablets by HPLC and Evaluation of Interchangeability With UV and Turbidimetric Methods

BACKGROUND

Marbofloxacin (MAR) is a veterinary antimicrobial, marketed in injectable solution, oral suspension, and tablets. MAR has no monograph for tablet evaluation in official compendiums. High Performance Liquid Chromatography (HPLC) methods present in the literature for evaluating MAR in tablets do not follow the principles of green and sustainable analytical chemistry.

OBJECTIVE

A green, clean, and sustainable method by HPLC was developed and validated to evaluate the content and stability of MAR in tablets, in addition to comparing it with other methods available in the literature.

METHOD

A C8, 5 µm, 4.6 × 150 mm (ACE®) column, purified water with 0.2% formic acid-ethanol (70:30, v/v) as the mobile phase, and a flow rate of 0.7 mL/min at 296 nm were used.

RESULTS

The method was linear over a concentration range of 1-10 μg/mL, selective for tablet matrix and forced degradation, precise with relative standard deviations (RDS) less than 5%, accurate with recovery of 99.99%, and robust to changes in the mobile phase, flow rate, wavelength, equipment, and column brand. The retention time for MAR was approximately 3.1 min.

CONCLUSIONS

The method can be used in routine analysis of MAR in tablets in chemical-pharmaceutical laboratories. Furthermore, it can be used to verify the stability of MAR-based products and proved to be interchangeable with spectrophotometric method in the UV region and turbidimetric microbiological method.

HIGHLIGHTS

A green method for evaluation of marbofloxacin tablets by HPLC was developed and validated. Additionally, it has been shown to be interchangeable with UV and turbidimetric methods.

Overview of Analytical Methods for Evaluating Tinidazole

BACKGROUND

Tinidazole (TIN) has amoebicidal, giardicidal, antifungal, and antimicrobial activities. It is marketed in the form of tablets. Analytical methods to assess the quality of TIN-based products are essential for correct pharmacotherapy.

OBJECTIVE

The objective of this review is to show an overview of the existing analytical methods for evaluating TIN, according to the quality control (QC) analysis routine and green analytical chemistry (GAC).

RESULTS

Official compendia show a method for evaluating TIN in tablets by nonaqueous titration, which has limitations (materials on the mg scale using solvents considered not recommended and harmful). The literature shows some analytical methods for evaluating TIN, both physicochemical and microbiological. The most used physicochemical method is UV (41%), and second is HPLC (28%). Among the microbiological methods, agar diffusion and turbidimetric methods are equally divided. The most studied matrix is TIN tablets (73%), and the most used solvent is methanol.

CONCLUSIONS

The literature shows space for the development of analytical methods according to GAC for evaluating TIN, optimizing time, resources, and materials, reducing waste generation, and opting for less aggressive reagents, solvents, and diluents.

HIGHLIGHTS

This review shows the status of analytical methods, both physicochemical and microbiological, for the analysis of TIN in pharmaceutical matrix, in the context of routine analysis of the chemical-pharmaceutical industries and of GAC.

Review of Analytical Methods for Evaluating Azithromycin in the Context of Green Analytical Chemistry

BACKGROUND

Azithromycin (AZT) is an antimicrobial available in different pharmaceutical forms and many people can have access to this medicine. Therefore, the existence of adequate and reliable analytical methods for evaluating the quality of AZT and AZT-based products is essential.

OBJECTIVE/METHODS

The purpose of this review is to discuss the analytical methods for evaluating AZT present in the literature and official compendia in the context of Green Analytical Chemistry (GAC).

RESULTS

Among the methods found in the literature for evaluating AZT, the most used method is HPLC (62%) followed by TLC (14%) and the microbiological method by agar diffusion (14%). Even pharmacopoeias recommend the analysis of AZT by HPLC or agar diffusion. Acetonitrile and methanol account for 35% of the most used solvents in the analyses, followed by buffer.

CONCLUSION

AZT lacks analytical methods in the context of GAC. Both physical-chemical and microbiological methods can contemplate the environmentally friendly way to analyze AZT and AZT-based products, depending only on the chosen conditions. Ethanol, purified water, acetic acid instead of methanol, acetonitrile, buffer, formic acid in the physical-chemical methods are excellent alternatives. However, in the microbiological method, turbidimetry is a great option instead of agar diffusion.

An Overview of Analytical Methods for the Quantification of Marbofloxacin in Pharmaceutical, Biological and Food Matrices

BACKGROUND

Marbofloxacin (MAR), a second-generation fluoroquinolone, is used in veterinary medicine in the form of tablets. It has a broad spectrum of action, low toxicity, and limited development of bacterial resistance. The analytical methods available in the literature become more important since MAR in tablets does not have a monograph in official compendiums.

OBJECTIVE

Thus, the purpose of this review is to display them according to the analyzed matrix and place them according to the conditions used in the scope of green analytical chemistry, in addition to discussing possible gaps and opportunities for the development of new methods.

RESULTS

MAR, being an antimicrobial, presents both physical-chemical (93%) and microbiological (7%) methods in the literature. Among the methods found, 53% are for analysis of food matrices using preferably HPLC and TLC-MS. 27% are for analysis of biological matrices and 20% are for analysis of pharmaceutical matrices, and in both HPLC is preferably used.

CONCLUSIONS

Therefore, there is still a gap in the literature in relation to other options of analytical methods for the analysis of MAR, which are faster, such as microbiological turbidimetry, sustainable, such as miniaturized methods, and ecologically correct, such as those that do not usetoxic organic solvents.

HIGHLIGHTS

A review of the status of analytical methods available in the literature for assessing the quality of MAR and MAR-based products were exhibited and discussed, as well as new opportunities for analysis according to green analytical chemistry.