A jury has begun deliberations in the trial of Elizabeth Holmes, who is accused of lying about her blood-testing start-up Theranos to patients and investors. 

Theranos falsely said it could detect diseases with a few drops of blood knowingly misleading investors, doctors, and patients about her startup's blood testing capabilities in order to take their money.

The prosecution argued that Ms. Holmes lied when her "house of cards" faced financial failure.

Elizabeth Holmes had confessed to the jury in her criminal fraud trial on Tuesday that she personally used the letterhead of Pfizer and Schering-Plough on documents sent to potential business partners and investors without the two companies' knowledge or consent.

Her step came to give the impression that the pharmaceutical companies were endorsing Theranos devices, when in fact they had distanced themselves from the startup.

By doing so, "she chose fraud over business failure. She chose to be dishonest with investors and with patients," prosecutor Jeffrey Schenk said in his closing remarks at the San Jose federal court where the trial has been underway for more than three months. "That choice was not only callous, it was criminal," he added.

Holmes said she had to intention to deceive anyone but was merely attempting to acknowledge other work Theranos had done with the relevant pharma companies.

Still, it was a mistake, she admitted.

"I wish I'd done it differently," said Holmes, speaking behind a plexiglass-enclosed witness box.

Ms. Holmes, 37, is facing nine counts of wire fraud and two counts of conspiracy, with each carrying a maximum sentence of 20 years in prison.

The jury comprising eight men and four women at the court in San Jose, California, will resume deliberations on Monday after being handed the case on Friday afternoon.

For years, Holmes claimed that with a tiny finger prick of blood, people would have more control over their health by allowing them to test for hundreds of conditions; an option made possible by Thoranos. 

Ms. Holmes was able to raise more than $900m from billionaires such as media magnate Rupert Murdoch and tech mogul Larry Ellison.

In 2014, the company was estimated to be worth $9 billion, more than the value of Uber and Spotify at the time.

But not long after, regulators and the media began asking probing questions about the efficacy of the technology, setting the company's downfall.