The Brazilian defender has never managed to secure regular first-team football at the Westfalenstadion since joining from Figueirense in 2008.
According to Bild, both Bayer Leverkusen and Borussia Monchengladbach are interested in Santana and the player's representative, Volker Struth, is keen to work something out with Dortmund.
"In this situation we will consider alternatives that can satisfy all sides," the agent told the paper.
Bild claims that Dortmund would be willing to allow Santana - who is under contract until 2013 - to leave if a club meets their valuation of €3.5 million for the 25-year-old centre-half.
In spite of his failure to nail down a place in Jurgen Klopp's starting lineup, Santana is said to be keen to continue plying his trade in the Bundesliga, having settled well in Germany and embraced the local culture.
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