Fast and New Microbiological Method for Evaluating the Potency of Marbofloxacin-Based Tablets

Area of Science:

• Microbiology
• Analytical Chemistry
• Green Chemistry

Background:

• Marbofloxacin (MAR) is a fluoroquinolone antimicrobial available in tablet form.
• Current official compendia lack a microbiological monograph for evaluating MAR tablet potency.
• Limited literature exists on microbiological evaluation methods for MAR tablets.

Purpose of the Study:

• To develop and validate a green, turbidimetric microbiological method for assessing MAR tablet potency.
• To establish a reliable assay for quality control of marbofloxacin formulations.

Main Methods:

• Utilized a purified water-ethanol diluent and Brain Heart Infusion (BHI) broth.
• Employed E. coli ATCC 25922 as the test microorganism.
• Incubation was performed in a shaker at 37°C for 4 hours.

Main Results:

• The method demonstrated linearity (0.25–2.56 µg/mL), selectivity, precision (RSD < 3.6%), and accuracy (100.20% recovery).
• The assay proved robust against variations in culture medium volume, shaker speed, and incubation temperature.
• The potency of MAR tablets was determined to be 96.98% using the developed method.

Conclusions:

• The developed turbidimetric method is a novel, rapid, and optimized option for routine quality control (QC) of MAR in tablets.
• This green analytical method provides a sustainable alternative for evaluating drug potency in final pharmaceutical products.
• The assay complements physicochemical analyses and supports the routine microbiological pharmaceutical analysis of MAR tablets.