Sure, you know the first leg is always more important than the second leg and now that barcelona have succeeded in wining them with 4 goals. The possibility for them to win back with this goal margin is something anyone can not think nor imagine that it will happen due to how consistant barcelona is towards chasing this champions league title, so I don't think if there's still a hope for dortmund.
It is quite possible to say there is no hope for Dortmund because I am also sure that Dortmund will not be able to score more goals in the second leg even though the match is held at their home ground. Because losing by four goals yesterday at Barcelona's home ground has made Dortmund's steps even harder to qualify for the next round in this season's Champions League and I am really not surprised by the result because Dortmund has not been good this season.
Very unlikely for Dortmund to make a comeback, 4 goals is a lot to recover from, it is clear that Barcelona are qualified for the semi final of the Champions League. Barcelona should worry less concerning the 2nd leg of the quarter final, the problem will be facing Inter in the semi finals, that match will be the toughest, tougher than the final, because both teams has their specialty, Barcelona with young talented players and Inter having rare experiences.
The semi final teams are already giving signs, each sides are making goals count for their advantage, next match will be for them defending their goals, and time to rest some important players.