(CNN) -- A University of Pittsburgh research professor accused of killing his wife with a lethal dose of cyanide pleaded not guilty Tuesday, according to Mike Manko, spokesman for the Allegheny County District Attorney's office.
Robert Ferrante was extradited from West Virginia to Allegheny County Jail in Pennsylvania on Tuesday morning, where he later appeared via video conference at his arraignment, according to the Allegheny County district attorney's office. The arraignment lasted only five minutes.
Ferrante pleaded not guilty in the death of his wife, Autumn Klein, 41, former head of women's neurology at the University of Pittsburgh Medical Center, according to the district attorney's office.
Several preliminary hearing dates have been set for early next month regarding the custody of Ferrante and Klein's 6-year-old daughter, Cianna, who is in the care of her maternal grandparents, the district attorney's office said. Hearings have also been set regarding Ferrante's assets.
Before his arrest on July 25, Ferrante was a researcher and professor of neurological surgery at the University of Pittsburgh. Part of his job included managing a laboratory where he conducted clinical trials using various drugs and chemicals, according to a criminal complaint.
Several text messages sent between the couple before Klein's death in April suggest that Ferrante urged Klein to try using creatine to get help her get pregnant, according to the complaint.
CNN Medical Correspondent Elizabeth Cohen reports that some people use creatine to build up muscle and may have some medicinal value, but that there is no connection between increased fertility and creatine use.
A source close to the case told CNN: "One of the theories the prosecution will work off of is that the cyanide was mixed with the creatine that Ferrante was urging his wife to take."
One day before Klein fell ill, Ferrante had used his University of Pittsburgh credit card to place an overnight order for more than a half a pound of cyanide. At the time the order was placed, there were no active projects at Ferrante's lab that involved the use of cyanide, according to the complaint.
Cyanide is a naturally occurring toxic substance that can be found in seeds of various plants. It is widely distributed throughout research laboratories as a chemical used in scientific experiments. Cyanide interferes with the ability of the body to use oxygen to produce energy, which can lead to rapid death.
"Cyanide in low doses will make you dizzy, you'll start breathing rapidly, but if you get it in big doses, it can actually make you stop breathing and that's what kills you," Cohen said.
On April 17, Allegheny County 911 dispatch received a call from Ferrante requesting medical assistance for his wife, who he said was possibly having a stroke, the complaint read. He described her condition as "conscious and breathing, but not alert." When paramedics arrived, they found Klein on the floor of the kitchen with a plastic bag containing creatine. Klein died on April 20.
In a statement made to detectives shortly after being informed of Klein's death because of cyanide poisoning, Ferrante said, "Why would she do that to herself? Who would do this to her?" according to the complaint.
A neighbor of the couple told CNN on Tuesday that nothing seemed amiss to her.
"I've never seen anything to suggest they were anything but a happy couple with a beautiful little girl," Blithe Runsdorf said.
She said the family had just gotten back from a trip to Puerto Rico and that they had never seemed happier. Runsdorf added that after his wife's death, Ferrante "acted like a guy who had everything pulled out from under him."
Ferrante's defense attorney, William Difenderfer, told CNN Tuesday that his client is "devastated not only for losing his wife but being accused of it."
After a nationwide manhunt, Ferrante was arrested on July 25 in West Virginia. He has also been placed on immediate and indefinite leave, according to University of Pittsburgh spokesman John Andrew Fedele.
Ferrante will appear in Allegheny County Court on September 23 for a preliminary hearing regarding the criminal homicide case.
Another neighbor to the couple said the community is concerned about the welfare of the couple's daughter, whom he described as "essentially an orphan now."
The neighbor said it was "no secret" in the neighborhood that Klein wanted to have another baby. However, Klein told the neighbor's wife that Ferrante did not want another child, said the neighbor, who asked not to be identified.
He called the whole situation "a tremendous shock" and added that this was not the kind of case where someone could say, "Oh, there was a lot of fighting." He said he was aware of none of that.
He described the couple as "dedicated and hard-working" and their daughter as "bubbly."
"They were hustling and trying to manage a family and the demands of the American Dream," the neighbor said.
Allison Malloy, Poppy Harlow, Sho Wills, Erinn Cawthon and Dominique Debucquoy-Dodley contributed to this report.