Functional biopolymer scaffolds are in high demand for tissue regeneration. In this study, we incorporated functionalized CNT in collagen or silk protein solution to generate biocomposite fibers by electrospinning. The addition of CNT reinforced the strength of the scaffolds and rendered the fibers electrical conductivity to not only facilitate the E-spun fiber formation but also grant the fibers an additional functionality that can be utilized for cell stimulation. Considering fiber dimension, alignment, mechanical strength, electrical conductivity and biocompatibility, silk-CNT fibers containing a minute amount of CNT (0.05%) outperformed other fiber types. The modulation effect of these fibers was examined by their application in inducing polarization and activation of fibroblasts with cellular deficit. While the fibroblasts on both collagen-CNT and silk-CNT fibers synthesized a substantially higher level of collagen type III (COLIII) than cells on pure protein fibers to reduce the abnormally high COLI/COLIII ratio, electrical stimulation boosted the collagen productivity by 20 folds in cells on silk-CNT than on collagen-CNT due to silk-CNT's high electrical conductivity. The developed approach can be potentially utilized to remedy the dysfunctional fibroblasts for therapeutic treatment of diseases and health conditions associated with collagen disorder. (C) 2018 Elsevier Inc. All rights reserved.