Can the Sensor if DSLR can be replace?

i was cleaning the sensor of my canon 550D then it was hot at that time when i cleaned and peek at the sensor a drop of my sweat fell into the sensor and i wiped it with cotton buds to dry it off. when i already done wiping eat theres this like a scar of wet that never goes away. its been 3 weeks it still the there. it can still take very good pictures but when i take a picture on a white background i can notice small blacks (the wet scars) when zoomed in on Video mode.. pls. help. can the sensor of this can be replace or can be fixed through a canon service center. sorry for my bad english..