RETRACTED: Evaluation of the surface chemistry and drug-polymer interaction of semi-crystalline micro-particles for the development of controlled release formulations

Isoniazid-loaded orodispersible strips: Methodical design, optimization and in vitro-in silico characterization

Drug treatment remains the most effective global approach to managing and preventing tuberculosis. This work focuses on formulating and evaluating an optimized polyvinyl alcohol-polyethylene glycol based orodispersible strip containing isoniazid, a first-line anti-tubercular agent. A solvent casting method guided through a Taguchi experimental design was employed in the fabrication, optimization and characterization of the orodispersible strip. The optimized strip was physically amalgamated with a monolayer, uniformly distributed surface geometry. It was 159.2 ± 3.0 µm thick, weighed 36.9 ± 0.3 mg, had an isoniazid load of 99.5 ± 0.8%w/w, disintegration and dissolution times of 17.6 ± 0.9 s and 5.5 ± 0.1 min respectively. In vitro crystallinity, thermal measurements and in silico thermodynamic predictions confirmed the strip's intrinsic miscibility, thermodynamic stability and amorphous nature. A Korsmeyer-Peppas (r = 0.99; n > 1 = 1.07) fitted kinetics typified by an initial burst release of 49.4 ± 1.9% at 4 min and a total of 99.8 ± 3.3% at 30 min was noted. Ex vivo isoniazid permeation through porcine buccal mucosa was bi-phasic and characterized by a 50.4 ± 3.8% surge and 95.6 ± 2.9% at 5 and 120 min respectively. The strip was physicomechanically robust, environmentally stable and non-cytotoxic.

Long-term antibacterial performances of biodegradable polylactic acid materials with direct absorption of antibiotic agents

In this study, polylactic acid (PLA) disks with antibacterial performances were prepared using 3D printing technology combined with direct adsorption of the antibiotic agents in solution baths. The effects of the layer thicknesses for the building of the 3D printing PLA disks and the amounts of antibiotic agents absorbed onto the sample surfaces on their antibacterial activities were investigated. The antibiotic agent release profiles from the samples surface into the buffer solution show that the antibacterial performances of these samples can reach up to 28 days. With a decrease in the concentration of antibiotic agent in the solution bath, the amount of antibiotic agent adsorbed on the sample surfaces also decreases, but their antibacterial performances can still maintain at least 7 days. In the bioactivity tests of the various organisms, the release amount of antibiotic agent from the sample can inhibit E. coli and S. aureus for over 80% up to 28 days. In the antibacterial activity tests, a PLA disk with suitable antibiotic agents covering its surface has a good inhibitory effect on the growth ability of S. aureus of less than 50% in six hours.

In this study, we developed a surface modification of 3D printing PLA disks. The relative optical density of the S. aureus in the solution can reduce to 40% using the PLA disk directly absorbed with suitable antibiotic agents.