Taking the sting off needles

IISc. scientists create ‘painless microneedle’

The microneedles are arranged in a set of several needles to deliver drugs of a required quantity.

For diabetics who need frequent insulin injections, children who go through a battery of inoculations, or those on drips — here is a novel innovation that takes the sting off injections.

A team of scientists and engineers at the Indian Institute of Science (IISc.) have created a ‘microneedle’ that is around third the thickness of conventionally used ones. With a diameter of just 130 microns, these injections can deliver drugs almost painlessly.

Unlike the conventional stainless steel needles, these microneedles are made of silicon and arranged in a set of several needles to deliver drugs of a required quantity. The team’s research was published in the latest edition of the journal

Microelectronic Engineering.

‘Needle coated’

But the team had a challenge to resolve: silicon is not always “biocompatible”. Silicon reacts with blood plasma and can corrode with time. “So we coated the needle with very thin layers of titanium and gold through electroplating,” said K.B. Vinayakumar, lead author and research scholar at the Department of Instrumentation and Applied Physics at IISc.

Strong enough

The needles are strong enough to withstand the “resistive force” of skin without breaking, he added. Another added advantage of microneedles was the relative efficiency with which they could be mass-fabricated, said K. Rajanna, professor in the department. The microneedles were still at the animal-testing stage and it could be a while before they are tested clinically on humans, he added.

The microneedles were developed in collaboration between several IISc. departments, including the Centre for Nano Science and Engineering, under the National Program on Micro and Smart Systems.