Mina, 23, has been linked to the La Liga giants, who have an option to buy the defender after the World Cup.
However, Mattos said Barca were keen to land the nine-time Colombia international in January, although Palmeiras want to keep the centre-back until the off-season.
"It's true that Barcelona came for Mina with another offer but also that Palmeiras want Mina to stay here," he said.
"We are going to wait for him to arrive in Sao Paulo and we will talk.
"If Palmeiras is satisfied with any situation so that he leaves before, we will do it. Otherwise, he will stay with us."
Barca are said to have a right to buy the defender for €9 million at the end of the season, while the Brazilian side reportedly want €12m to let Mina leave in January.