Tetracycline Water Soluble Formulations with Enhanced Antimicrobial Activity

Area of Science:

• Pharmaceutical Sciences
• Materials Science
• Microbiology

Background:

• Tetracycline (TC) exhibits poor water solubility, limiting its oral administration.
• Developing novel drug delivery systems is crucial for enhancing antibiotic efficacy and overcoming administration challenges.

Purpose of the Study:

• To synthesize and characterize sodium lauryl sulphate (SLS) and cetrimonium bromide (CTAB) micelles encapsulating tetracycline (TC).
• To evaluate the enhanced antimicrobial activity and toxicity of the novel TC micelles against various bacterial strains and human cells.

Main Methods:

• Micelles (SLS@TC, CTAB@TC) synthesized and characterized using techniques like DSC, FT-IR-ATR, UV/vis, and 1H-NMR.
• Antimicrobial activity assessed via MIC, MBC, and IZ assays against Gram-positive and Gram-negative bacteria.
• In vitro toxicity evaluated using human corneal eukaryotic cells (HCECs) and in vivo toxicity using Artemia salina.

Main Results:

• Both SLS@TC and CTAB@TC micelles demonstrated improved water solubility and enhanced antimicrobial activity compared to free TC.
• CTAB@TC showed significantly higher efficacy against Staphylococcus epidermidis (550-fold increase in MIC).
• SLS@TC exhibited bactericidal activity, while CTAB@TC was bacteriostatic; both showed low toxicity in vitro and in vivo.

Conclusions:

• SLS@TC and CTAB@TC micellar formulations represent promising strategies for improving tetracycline's therapeutic potential.
• These novel formulations offer enhanced antimicrobial efficacy and acceptable safety profiles, warranting further investigation as potential new antibiotics.