The Armenian playmaker has scored four goals in 19 appearances since arriving from Manchester United in January. But Mkhitaryan insists he wants to become a different player than the one who graced the Westfalenstadion, where he scored 41 goals in 140 appearances over three seasons.
He told BBC's Football Focus: "I'm the worst critic in my football game and I don't need extra criticism.
"I know very well what I am giving to the team and what the team gives me."
Speaking to the Gunners' official website: "I don't think you're going to see the Dortmund Mkhitaryan, because in Dortmund the philosophy was different, the playing style was different, the league was different.
"Arsenal are playing in a different league with a different manager and different team-mates.
"I don't want to see the old Mkhitaryan being here at Arsenal. I want to be someone new, someone else who can show that he's capable of doing the same for Arsenal as well.
"I'm not just playing football to play, I'm always playing football to win games and titles.
"At the end of your football career, people are going to remember you for what you have achieved, what you have won. I'm playing to win titles, I'm doing my best for this club to win titles and of course that's my main goal."