Formulation of Multidrug-Loaded Hydrogels

Carbomer 940 was dissolved in ddH₂O to prepare 1 wt% carbomer gel (CBMG) [21 (link)]. Specifically, 1 g of Carbomer 940 (Macklin Reagent, Shanghai, China) was dissolved in 100 mL of ddH₂O and stirred at 60 °C for 30 min. Then, 0.25% triethanolamine (Adamas, Shanghai, China) was added into the carbomer solution to adjust the final pH to 6.5–7.5. After stirring for 10 min, CBMG was prepared. Afterwards, drugs (Rif, Van, and Que) in powders of different weights were mixed with CBMG under stirring for 30 min and left overnight at room temperature to form combined hydrogels. The crude hydrogels were washed three times with ddH₂O to remove the uncombined material and stored in a sealed bottle at 4 °C.