Research Highlight

Antibiotic-releasing microspheres

doi:10.1038/nindia.2013.96 Published online 22 July 2013

Researchers have designed a new kind of hydrogel microsphere that can slowly release ciprofloxacin hydrochloride, a widely used antibiotic . They prepared the microspheres using xanthum gum (a bacterial polysaccharide) and polymers. This microsphere will be very useful for delivering the antibiotic in order to treat various bacterial infections.

Xanthum gum is a polysaccharide secreted by the bacterium Xanthomonas campestris. It is used as a food-thickening agent in salad dressings and as a stabilizer in cosmetic products to prevent ingredients from separating. It is also used in the oil industry to thicken drilling mud.

No studies have explored its potential as a drug-delivering agent.

Researchers synthesized an interpenetrating polymer network containing the hydrogel microspheres by mixing xanthum gum with a superabsorbent polymer and poly(vinyl alcohol) in a water-in-oil emulsion. They produced a range of different microspheres by varying the ratio of the superabsorbent polymer to poly(vinyl alcohol). Sophisticated electron microscopy revealed that the microspheres had loose and rigid surfaces.

After loading the microspheres with the antibiotic, the researchers tested their ability to release the antibiotic in both acidic and alkaline media. All the produced microspheres released the antibiotic successfully. The drug-loaded polymer-based microspheres changed from a rubbery state to a dry state on releasing the drug through an unusual diffusion process.

The researchers say that these antibiotic-loaded interpenetrating-polymer-network microspheres are suitable for use in applications requiring sustained drug release.


  1. Bhattacharya, S. S. et al. Preparation and in vitro evaluation of xanthan gum facilitated superabsorbent polymeric microspheres. Carbohydr. Polymer. 98, 64-72 (2013)