Tannic Acid and Copper-Modified ZIF-8 Metal Organic Framework as a Cefotaxime Delivery System for Antimicrobial...

Antibiotic resistance has become a global public health threat. Cefotaxime (CTX), a third-generation cephalosporin, is approved for use in infants, children, and adults with various microbial infections, particularly those affecting the central nervous system. This study aimed to synthesize and characterize zeolitic imidazolate framework (ZIF)-8-based drug delivery systems (DDSs) to enhance antimicrobial activity and control CTX release.

ZIF-8 was synthesized via the coordination network of Zn ions and 2-methylimidazole and subsequently modified with tannic acid (TA) and copper ions (Cu²⁺). ZIF-8 MOF and its derivatives were characterized by Fourier Transform Infrared, zeta potential, in vitro dissolution rate, and in vitro antimicrobial activity.

The drug loading capacity and encapsulation efficiency were found to be 39.50 ± 1.19% and 98.75 ± 2.96%, respectively, for ZIF-8@ TA@CTX, and 40.75 ± 1.22% and 97.75 ± 2.93%, respectively, for ZIF-8@TA@Cu@CTX. Following 48 hours, the drug released from ZIF-8@TA@ Cu@CTX was detected at 62.83 ± 1.89% at pH 5.0 and 83.19 ± 2.50% at pH 7.4 after 48 h, with dissolution profiles best fitting the Korsmeyer–Peppas model. The synthesized DDSs demonstrated a higher antibacterial activity against gram-positive bacteria than against gram-negative bacteria.

ZIF-8 MOF DDS may serve as an alternative for delivering drugs to infected areas due to their controlled release under low pH conditions.