Efficient local gene transfection on a tissue scaffold is dependent on good cell-adhesion characteristics. In this work, the thermoresponsive gelatin-functionalized polycaprolactone(PCL) films were proposed for improv...Efficient local gene transfection on a tissue scaffold is dependent on good cell-adhesion characteristics. In this work, the thermoresponsive gelatin-functionalized polycaprolactone(PCL) films were proposed for improvement of cell adhesion and intelligent recovery of gene-transfected cells. Functional copolymer brushes(PCL-g-P(NIPAAm-co-MAAS)) were first prepared via surface-initiated ATRP of N-isopropylacrylamide(NIPAAm) and methacrylic acid sodium salt(MAAS) from the initiatorfuncationalized PCL surfaces. The pendant carboxyl end-groups of the PCL-g-P(NIPAAm-co-MAAS) surface were subsequently coupled with gelatin via carbodiimide chemistry to produce the thermo-responsive gelatin-functionalized PCL surface. The thermo-responsive gelatin-functionalized PCL film surface can improve cell adhesion and proliferation above the LCST of P(NIPAAm) without destroying cell detachment properties at lower temperatures. The dense transfected cells can be recovered simply by lowering culture temperature. The thermo-responsive gelatin-functionalized PCL films are potentially useful as intelligent adhesion modifiers for directing cellular functions within tissue scaffolds.展开更多
Electrospun porous films doped with the green-synthesized CdSe quantum dots were synthesized. Glycerol was chosen to prepare the quantum dots （ QDs）, with the highest quantum yield of 78.28%. Polycaprolactone （PCL...Electrospun porous films doped with the green-synthesized CdSe quantum dots were synthesized. Glycerol was chosen to prepare the quantum dots （ QDs）, with the highest quantum yield of 78.28%. Polycaprolactone （PCL） was electrospun with CdSe QDs to avoid the QDs＇ toxicity and improve the QDs＇ cytocompatibility. The electrospun QDs-doped films preserve the original QDs＇ fluorescence. Pores can be detected from the SEM of the films, predicting the possibility of loading drugs in the cancer therapy. The cell proliferation assay shows excellent cytocompatibility of the eletrospun CdSe-QDs-doped films. The present eletrospun CdSe- QDs-doped porous films are cytocompatibale, highly-fluorescent and ootential to load drugs in cancer therapy.展开更多
The melting and crystallization behaviors of poly（e-caprolactone） （PCL） ultra-thin films with thickness from 15 ran to 8 nm were studied by AFM technique equipped with a hot-stage in real-time. It was found that m...The melting and crystallization behaviors of poly（e-caprolactone） （PCL） ultra-thin films with thickness from 15 ran to 8 nm were studied by AFM technique equipped with a hot-stage in real-time. It was found that melting can erase the spherulitic structure for polymer film with high thickness. However, annealing above the melting point can not completely erase the tree-like structure for the thinner polymer film. Generally, the structure formation of thin polymer films of PCL is controlled not only by melting and crystallization but also by dewetting during thermal annealing procedures, and dewetting predominates in the structure formation of ultra-thin films. However, the presence of tree-like morphology at 75 ℃ may be due to the strong interaction between PCL and mica surface, which may stick the PCL chains onto the mica surface during thermal annealing process. Moreover, the growth of the dendrites was investigated and it was found that crystallization is followed from a dewetted sample, and the branches did not grow with the stems. The crystallization of polymer in the ultra- thin films is a diffusion-controlled process. Both melting and crystallization behaviors of PCL in thin films are influenced by film thickness.展开更多
基金supported by the National Natural Science Foundation of China(51173014,51221002,51325304,51373017 and 51302009)the Research Fund for the Doctoral Program of Higher Education of China(20120010120007)
文摘Efficient local gene transfection on a tissue scaffold is dependent on good cell-adhesion characteristics. In this work, the thermoresponsive gelatin-functionalized polycaprolactone(PCL) films were proposed for improvement of cell adhesion and intelligent recovery of gene-transfected cells. Functional copolymer brushes(PCL-g-P(NIPAAm-co-MAAS)) were first prepared via surface-initiated ATRP of N-isopropylacrylamide(NIPAAm) and methacrylic acid sodium salt(MAAS) from the initiatorfuncationalized PCL surfaces. The pendant carboxyl end-groups of the PCL-g-P(NIPAAm-co-MAAS) surface were subsequently coupled with gelatin via carbodiimide chemistry to produce the thermo-responsive gelatin-functionalized PCL surface. The thermo-responsive gelatin-functionalized PCL film surface can improve cell adhesion and proliferation above the LCST of P(NIPAAm) without destroying cell detachment properties at lower temperatures. The dense transfected cells can be recovered simply by lowering culture temperature. The thermo-responsive gelatin-functionalized PCL films are potentially useful as intelligent adhesion modifiers for directing cellular functions within tissue scaffolds.
基金Shanghai Leading Academic Discipline Project,China，Shanghai Key Laboratory Project,China，Doctoral Fund of Ministry of Education of China，National Natural Science Foundation of China
文摘Electrospun porous films doped with the green-synthesized CdSe quantum dots were synthesized. Glycerol was chosen to prepare the quantum dots （ QDs）, with the highest quantum yield of 78.28%. Polycaprolactone （PCL） was electrospun with CdSe QDs to avoid the QDs＇ toxicity and improve the QDs＇ cytocompatibility. The electrospun QDs-doped films preserve the original QDs＇ fluorescence. Pores can be detected from the SEM of the films, predicting the possibility of loading drugs in the cancer therapy. The cell proliferation assay shows excellent cytocompatibility of the eletrospun CdSe-QDs-doped films. The present eletrospun CdSe- QDs-doped porous films are cytocompatibale, highly-fluorescent and ootential to load drugs in cancer therapy.
基金supported by the National Natural Science Foundation of China for General (Nos. 50303017,50373044),Major (Nos. 20490220, 50390090)the Special Funds for Major State Basic Research Projects(No. 2003CB615600)
文摘The melting and crystallization behaviors of poly（e-caprolactone） （PCL） ultra-thin films with thickness from 15 ran to 8 nm were studied by AFM technique equipped with a hot-stage in real-time. It was found that melting can erase the spherulitic structure for polymer film with high thickness. However, annealing above the melting point can not completely erase the tree-like structure for the thinner polymer film. Generally, the structure formation of thin polymer films of PCL is controlled not only by melting and crystallization but also by dewetting during thermal annealing procedures, and dewetting predominates in the structure formation of ultra-thin films. However, the presence of tree-like morphology at 75 ℃ may be due to the strong interaction between PCL and mica surface, which may stick the PCL chains onto the mica surface during thermal annealing process. Moreover, the growth of the dendrites was investigated and it was found that crystallization is followed from a dewetted sample, and the branches did not grow with the stems. The crystallization of polymer in the ultra- thin films is a diffusion-controlled process. Both melting and crystallization behaviors of PCL in thin films are influenced by film thickness.
