HOUSTON -- A jury sentenced a cancer researcher to 10 years in prison after she was convicted of poisoning her colleague, who was also her lover, by lacing his coffee with a chemical found in antifreeze.

Dr. Ana Maria Gonzalez-Angulo, 43, a breast cancer doctor based at Houston's famed Texas Medical Center, had been involved in a sexual relationship with her fellow researcher, Dr. George Blumenschein.

Prosecutors said the affair turned into a "fatal attraction" and she poisoned him with ethylene glycol after Blumenschein spurned her in favour of Evette Toney, his longtime live-in girlfriend with whom he was trying to start a family. Blumenschein survived the poisoning.

A jury on Friday convicted Gonzalez-Angulo of aggravated assault.

During closing arguments in the trial's punishment phase, prosecutors asked jurors to sentence Gonzalez-Angulo to at least 30 years in prison, saying this should be treated as a murder case as she stole years from Blumenschein's life. Blumenschein testified last week his life span was shortened by the poisoning as he now has only 40 per cent of his kidney function.

"Don't feel bad for one second about sending her to prison. She did that herself," said prosecutor Justin Keiter.

Defence attorney Derek Hollingsworth asked jurors to sentence Gonzalez-Angulo to probation, saying she should not be judged solely by this one event in her life. He pointed out the work she had done helping patients during her career. On Friday, several patients told jurors Gonzalez-Angulo was a compassionate person who had tirelessly worked to treat them.

"It's not the right result to send her to prison for a lengthy period of time ... When you look at the entirety of her life, (probation) makes sense," he said.

Hollingsworth said probation will not be easy for Gonzalez-Angulo as her conviction means she will never practice medicine again.

Keiter said Gonzalez-Angulo's good work as a doctor should not excuse her actions. He said probation would not fix what is wrong with Gonzalez-Angulo.

"You cannot fix evil, you can't. You can't fix someone who is cold and calculating and manipulative," he said.

Blumenschein told jurors that he became sick Jan. 27, 2013, not long after he and Gonzalez-Angulo had been intimate, and that he immediately suspected his lover of spiking his coffee. Witnesses testified that Gonzalez-Angulo had access to ethylene glycol at the University of Texas M.D. Anderson Cancer Center where she and Blumenschein worked.

The defence team had noted a prosecution expert's testimony that Blumenschein could have ingested the poison two days earlier.

Gonzalez-Angulo's attorneys had argued during the trial that other people, including Toney, might have been responsible for the poisoning, an allegation that Toney has denied.