title: Patterned substrates fabricated by a controlled freezing approach and biocompatibility evaluation by stem cells.
abstract: Patterned substrates have been widely used in the studies investigating how to regulate cell growth and alignment. Such substrates may be fabricated by various techniques such as photolithography, soft lithography and microcontact printing. We report here a facile approach to fabricate aligned and grid surface patterns by a controlled freezing approach and further investigate their biocompatibility. The fabrication has been demonstrated with polymers (hydrophilic & hydrophobic), nanoparticles (organic & inorganic), or mixtures of these components. For the aligned surface patterns, the spacings between the patterned ridges can be tuned by varying the freezing rates. The biocompatibility of the substrates is evaluated by WST-8 viability tests with cell counting kit-8 (CCK-8) and by culturing with mouse mesenchymal stem cells (mMSCs). Three surface-patterned substrates (PLGA, PLGA nanospheres with chitosan, and silica colloids) are evaluated in more details to show that the mMSCs can grow alongside the aligned ridges while the cells grow randomly when plain glass slides are used as control. Further observations show that PLGA substrates undergo degradation, and are thus unsuitable for cell culture over the longer term. On the other hand, the PLGA-chitosan substrate and silica substrate were stable and could maintain mMSC alignment throughout the culture period.
authors: Department of Chemistry, University of Liverpool, Oxford Street, Liverpool L69 7ZD, UK.
authors: Lei
authors: L
authors: Qian
authors: Department of Chemistry, University of Liverpool, Oxford Street, Liverpool L69 7ZD, UK.
authors: Adham
authors: A
authors: Ahmed
authors: Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, UK.
authors: Laurence
authors: L
authors: Glennon-Alty
authors: Department of Chemistry, University of Liverpool, Oxford Street, Liverpool L69 7ZD, UK; Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, UK.
authors: Yonghong
authors: Y
authors: Yang
authors: Institute of Translational Medicine, University of Liverpool, Liverpool L69 3GE, UK.
authors: Patricia
authors: P
authors: Murray
authors: Department of Chemistry, University of Liverpool, Oxford Street, Liverpool L69 7ZD, UK. Electronic address: zhanghf@liv.ac.uk.
authors: Haifei
authors: H
authors: Zhang
mesh_terms: D001672:Biocompatible Materials; D048271:Chitosan / Q000737:chemistry; D005615:Freezing; D019344:Lactic Acid / Q000737:chemistry; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D017550:Spectroscopy, Fourier Transform Infrared; D013234:Stem Cells / Q000166:cytology*
chemical_list: D001672:Biocompatible Materials; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D048271:Chitosan
keywords: Controlled freezing; Mesenchymal stem cells; Nanoparticles; Surface patterns