Parents who dread the routine childhood vaccinations could have some help at hand.
Scientists in the US are developing a new method of delivering every childhood vaccine in a single injection.
"We are very excited about this work because, for the first time, we can create a library of tiny, encased vaccine particles, each programmed to release at a precise, predictable time, so that people could potentially receive a single injection that, in effect, would have multiple boosters already built into it," said Professor Robert Langer, from the Massachusetts Institute of Technology.
"This could have a significant impact on patients everywhere, especially in the developing world where patient compliance is particularly poor."
The researchers developed "cups" from PLGA, a biocompatible plastic-like polymer already approved for use in medical devices such as implants and prosthetic devices.
Silicon moulds were created for the cups and lids in large arrays of around 2,000 at a time.
Once the polymer cups were made, a special automated dispensing system was used to fill each one with a drug or vaccine.
In mice, the "cups" were shown to release in sharp bursts without prior leakage nine, 20, and 41 days after injection.
A single injection of the cups was able to induce a strong immune response comparable to that from two conventional injections with double the dose, the scientists found.
The researchers are now testing the delivery particles with a variety of drugs including existing vaccines and others still in development.
The findings are reported in the journal Science.
