New
Delhi, August 22 (India Science Wire): Researchers at Indian Institute of
Technology-Hyderabad have developed a method to produce controlled-release oral
tablets for treating fungal infections and kala azar. The tablets were found to
release the drug Amphotericin B in a sustained and controlled manner over a
period of 10 days.
Amphotericin
B is the drug of choice for fungal infections of the abdomen and heart valves,
fungal pneumonia, and kala azar. However, it is costly, causes toxicity and its
bioavailability is poor. The drug is administered through injection, which
results in uncontrolled release into the blood stream.
The
researchers have developed the oral tablet by loading the drug on to gelatin
nano-fabric. They chose gelatine since it is nontoxic and biocompatible,
besides being biodegradable. It is used in food and medical industries. The drug
was loaded on to gelatin and was then drawn out in the form of nano fibres
through the process of electrospinning. It involves use of electric force to
draw out charged threads of polymers into fibres with diameters in the order of
some hundred nanometres. In order to improve structural consistency in aqueous
conditions, saturated vapours of a chemical called glutaraldehyde were used.
The
team has also found that the nano-fibrous oral tablet was stable over a wide
range of pH, which means that it would not be destroyed in the gastrointestinal
track before drug absorption into the blood stream.
Explaining
the rationale for using nanofibres to produce the oral tablets, researchers
said, “nanofibres – fibres that are a hundred thousand times thinner than the
human hair – are increasingly being considered as a medium for controlled
release of drug molecules because of their large surface area and porosity”.
The research was led by Prof. Saptarshi
Majumdar and Dr. Chandra Shekhar Sharma. The study results have been published
in journal Nano-Structures and Nano-Objects. The paper has been
co-authored by Dr. Anindita Laha, Ms. Mrunalini Gaydhane.
By Sunderarajan Padmanabhan