Development of the dynamic approach for detection of Salmonella Typhi biofilm via optimizations of interaction with safranin dye

Salmonella Typhi infection is showing as a negative alarm for human health due to the occurrence of life-threatening typhoid fever and the emergence of antibiotic resistance. The infection becomes chronic due to the biofilm formation of S. Typhi, which plays a significant role in antibiotic resistance. The S. Typhi can survive under various stress conditions such as antibiotic stress, host immune stress, environmental stress, and nutritional stress in the biofilm stage. Biofilm provides a protective cover to the S. Typhi and prevents the entry of antibiotics inside the bacterial cells. Thus, biofilm is the root cause of the problem. Therefore, this study explores the easy detection of S. Typhi biofilms using safranin dye with specific concentrations. We performed the biofilm growth kinetics, qualitative assessment of the biofilm formations, and safranin interactions to finalize the specific concentrations of safranin (0.5 mg/mL) to detect the S. Typhi biofilm condition. The study was validated at 0.5 mg/mL safranin concentrations with the help of RSM analysis and kinetics study of the typhoidal biofilm. The study is important because the obtained results indicated the precise detection of S. Typhi biofilm, which is useful for all phases of biofilm detection. The study provided new directions for typhoidal biofilm staining that could be an emerging methodology in the area of health sciences.