PHILADELPHIA — A long-awaited scientific presentation by Theranos CEO Elizabeth Holmes on Monday amounted to a plea and a promise:

Forget the past. We’ll redeem ourselves soon.

Holmes declined to provide any data about the company’s controversial Edison platform for running diagnostic tests based on the blood from a single finger prick. The company voided results for thousands of those tests earlier this year, after their accuracy came under fire.

Instead, Holmes unveiled a new device called the miniLab, which has been in development for the past five years. It’s meant to condense blood-testing technology that would normally require several large machines into a single desktop device.

Holmes presented internal data showing that the platform can handle an eclectic menu of tests, ranging from general lipid panels for cholesterol to more specialized tests, including one for Zika. Eventually, she said the miniLab would be able to test tiny quantities of blood for viral or bacterial infection; analyze blood chemistry, including enzymes and fats; probe for problems in the immune system; and assess blood components such as platelets and white blood cells.

But Theranos did not release any data that has been validated by a third party or subjected to peer review.

Holmes said the company is working on letting other labs validate the new technology. So far, though, all Theranos has to offer is internal data.

And it might have trouble winning trust based on that, after the fiascos of the past two years.

Federal regulators have banned Holmes from the diagnostics industry for two years, after the Centers for Medicare & Medicaid Services found that Theranos’s lab practices led to “immediate jeopardy to patient health and safety.’’ The company is also under a federal criminal investigation for possibly misleading investors about its activities and the value of its technology.

The presentation Monday at the annual American Association for Clinical Chemistry in Philadelphia was widely seen as Holmes’s last chance to regain credibility in the industry. The valuation of her company has slid to near zero, from a high of $9 billion.

There was a full house for the presentation, with a long line to get in the door. The crowd watched in silence for the 45-minute talk, which included photos of the inside of the miniLab and the miniature centrifuge, “nanotainers’’ for blood samples, and robotics used to perform the tests. Then audience members peppered Holmes with questions, breaking into applause for particularly tough queries.

Holmes did take a minute to acknowledge the controversy swirling around Theranos.

“We take full responsibility of our lab operations, and are working diligently to rectify all outstanding issues,’’ she said.

But she wouldn’t go much further than that. Instead, Holmes sought to distance the company from the blood-testing platform it had been touting for several years as a revolutionary technology.

“We know there’s a lot of questions about the past, and in the appropriate forum, we’ll address those,’’ she said.

Meghana Keshavan can be reached at Meghana.Keshavan@statnews.com. Follow Meghana on Twitter @megkesh