Brown scored four of his career-high 17 points in the final 39 seconds as Radford (7-5) battled to get past the Seahawks (5-3).
Radford won on a buzzer-beater for the third time this season.
With North Carolina-Wilmington (5-3) down five in the last three minutes, Chris Flemmings started a 7-0 rally and tied the game at 65 with 1:03 left.
Brown and Craig Ponder traded baskets to push the tie to 67 and Radford called a timeout with 11 seconds left. Brown's hook shot rolled in as the buzzer sounded.
Taj Owens scored a career-high 16 points with three assists and three steals.
The lead changed hands eight times with seven ties.