Transduction efficiency of pHK10-coated adenovirus with reducible linker (AEDP) and Cathepsin-B cleavable linker (AhxFKFLAhx) in serum free or serum-containing medium. Ad5, pHSSK10/Ad5, and pHCathK10/Ad5 showed statistically higher transduction in serum free conditions compared to serum conditions (p<0.008). *In serum free conditions, pHK10/Ad5, pH(d)K10/Ad5, and pHCathK10/Ad5 showed significantly higher transduction than Ad5, pH(d)K10/Ad5, and pHCath(d)K10/Ad5 (p<0.003), but no difference from each other. Ad5, pH(d)K10/Ad5, and pHCath(d)K10/Ad5 also showed no significant difference from each other in serum free conditions when p = 0.01.