Nicholas, who lost to Hiromi Kobayashi from Japan at the first play-off hole in the Evian Masters last Saturday, is one of four members of last year's Solheim Cup team in the field of 126.
"I have not had a top 10 in America this year, but my confidence is growing," said Nicholas.
Cheshire's Joanne Morley, Dale Reid from Scotland and the Barcelona-based French golfer Marie-Laure de Lorenzi are the other three Solheim Cup players in the field.
Morley finished fourth in France last week behind De Lorenzi, who is back in the form which earned her a record seven tournament victories in 1988.
Two weeks ago De Lorenzi won the Swiss Open, she leads the American Express merit table with winnings of pounds 53,168 from five tournaments this year.