Wiping dust off the sensor
If the specs on the sensor are still there after a high tech brush cleaning of the sensor, the final “nuclear option” is to clean the sensor with tissue and a solvent. Again there are companies who specialize in providing materials designed for this task. One such company is PhotoSol (www.photosol.com) who have a line of solvents and tissues (Sensor Swabs) marketed under the “Eclipse” name. Again the advantage of dealing with a company which produces products designated for digital sensor cleaning is that you can get technical support from them and their products are guaranteed to cause no harm when used as specified. Cleanliness is paramount when using swabs and cleaning fluids. Use the swabs only once and use the minimum amount of solvent required to dampen the swab. Pressure is generally not needed (and may be counterproductive), so a gentle wipe across the sensor is the way to go. After one wipe check the sensor and only repeat if necessary. As I said earlier, there’s no point in trying to remove every last minute speck of dust. If nothing shows up in real images, the sensor is clean enough.
Personally, I use conventional lens tissue and methanol to clean my sensors, but again I have experience and I’m willing to take the risk. So far I’ve had no problems, but I’d recommend going the commercial product route to anyone who is at all nervous about sensor damage.