You don't have to cut out your shampoo bottles just to get the last bits of it.

Scientists at The Ohio State University have discovered a special lining to let soap products flow easily out of plastic bottles.

The lining is made up of microscopic y-shaped structures that cradle the droplets of soap upwards above tiny air pockets that keep the shampoo or other contents from touching the side of the bottle.

The "y" structures are built with smaller nanoparticles made of silica, or quartz, which, when treated further, won't stick to soap.

According to inventors Bharat Bhushan and Philip Brown, the technique works on polypropylene, a common plastic used for packaging household goods.

"It's what you'd call a first-world problem, right? 'I can't get all of the shampoo to come out of the bottle,'" Bhushan, Ohio Eminent Scholar and Howard D. Winbigler Professor of mechanical engineer at Ohio State, said in a press release.

"Compared to soaps, getting ketchup out of a bottle is trivial. Our coating repels liquids in general, but getting it to repel soap was the hard part," Bhushan added.

He explained that surface tension causes the molecules of a substance to stick to each other. Ketchup and other sauces are mostly made of water, and water molecules tend to stick to each other more than they stick to plastic.

A commercial shampoo manufacturer suggested to the researchers to create a shampoo bottle lining that was cheap, effective and environment-friendly. According to the researchers, the tenacity of soap and shampoo products make the last drops cling to the insides of the bottles.

The micrometer quartz structures are as hard as glass and are covered in tiny branchlike projections. With these structures in place, soap is unable to spread across the lining of the bottle and instead forms into beads that roll across the surface.

The invention could increase recycling as plastic bottles need to be fully emptied and rinsed completely clean before they can be recycled.

The scientists announced their patent-pending technology in the journal Philosophical Transactions of the Royal Society.

Another inventor discovered a gadget that would help diners empty their sauce bottles. The Flying Saucer, which was created by Richard Fereday, has a crowdfunding campaign on Kickstarter.