‘I told him I do have a valid visa, but he told me that it doesn’t matter.’

Samira Asgari.

If everything had gone to plan, Samira Asgari would have been settling into a new home in Boston with her boyfriend on Saturday night.

Instead, the Iranian scientist said she was turned away at the airport gate in Frankfurt, Germany, when she tried to board a Saturday flight for Boston — the result of President Trump’s executive order to close US borders to refugees and non-US citizens from seven predominantly Muslim countries, citing national security concerns.

The order, signed on Friday, currently affects those traveling from Iran, Iraq, Libya, Somalia, Sudan, Syria, and Yemen.

“They took me a few meters away and took my passport and told me my visa’s not valid,” Asgari said in a Skype interview from Lausanne. “I told him I do have a valid visa, but he told me that it doesn’t matter. I asked him, ‘What can I do now?,’ and he told me to go home.”

Asgari said one other woman on her flight was also stopped at the gate.

Asgari, who holds a doctorate from the École Polytechnique Fédérale de Lausanne in Switzerland, had planned to work for a Harvard Medical School laboratory, searching for cures to tuberculosis. The lab also performs research for Type 1 diabetes and rheumatoid arthritis.

She would have worked under Dr. Soumya Raychaudhuri, a rheumatologist at Brigham and Women’s Hospital, who told the Globe he “couldn’t believe that somebody with a visa with her standing would be denied entry.”

Asgari was granted a J-1 Visa to work in the United States, Raychaudhuri said. She was also awarded two years of funding for her research from the Swiss National Science Foundation.

“I was really ready to go,” Asgari said. “I had done everything right.”

Before leaving for Boston, Asgari and her boyfriend quit their jobs, packed their apartment, and rented it to new tenants, who will arrive on Sunday.

Asgari said Raychaudhuri has extended his support in any way he can, and that friends and family in Switzerland have offered them a place to stay.

But for Asgari, this was her dream job.

“I realized I wanted to spend some time in Boston because it has such a great research community,” she said. “This is the job I planned for and dreamed about, and now I’m not going to have that.”

“I was proud of myself,” she added. “All of a sudden, it was gone.”