Browsing by Author "Cheng, Hsun"

Now showing 1 - 7 of 7

A supramolecular hydrogel self-assembled from pentafluorobenzyl-dipeptide
(2015-01-01)
Hsu, Shu-Min
;
Chang, Jui-Wen
;
Wu, Fang-Yi
;
Lin, Yu-Chun
;
Lai, Tsung-Sheng
We report a new aromatic-capped peptide amphiphile which is able to form a supramolecular hydrogel under neutral pH. This hydrogel can also be obtained by enzymatic transformation from the hydrogelator precursor. The newly discovered hydrogel has excellent biocompatibility for four different cell lines, thus making it a potentially useful scaffolding material for biomedical applications.
Electroactive Organic Dye Incorporating Dipeptides in the Formation of Self-Assembled Nanofibrous Hydrogels
(2014-10-01)
Liu, Yu-Hao
;
Hsu, Shu-Min
;
Wu, Fang-Yi
;
Cheng, Hsun
;
Yeh, Mei-Yu
In this study, we examined the self-assembly of four dipeptides conjugated with the electroactive dye naphthalenediimide (NDI). The presence of the NDI group at the N-terminus of Phe-Phe and Phe-Gly promoted the formation of one-dimensional (1-D) nanostructures and three-dimensional (3-D) colored hydrogels under both acidic and physiological conditions. The 1-D nanostructures of these gels were stabilized through intermolecular pi pi interactions of the conjugated systems and extended hydrogen bonding of the dipeptide units.
Functional Supramolecular Polymers: A Fluorescent Microfibrous Network in a Supramolecular Hydrogel for High-Contrast Live Cell-Material Imaging in 3D Environments
(2016-09-21)
Hsu, Shu-Min
;
Wu, Fang-Yi
;
Cheng, Hsun
;
Huang, Yu-Tang
;
Hsieh, Yi-Ru
A new bottom-up strategy based on aromatic peptide amphiphile is developed for a high-contrast visualization of 3D live cell-material imaging-something that has been difficult to achieve previously because of the problems associated with the diffraction of light by the nanosized peptide materials and the aggregation-caused quenching of aggregated pi-conjugated fluorophores in the nanostructures. This study reports an example of a novel supramolecular hydrogelator, naphthaleneimide-phenylalanine (NI-Phe), which forms a self-supporting hydrogel displaying a unique microfibrous network and promising aggregation-induced emission characteristics at pH 7.4. The storage modulus of the NI-Phe gel supports the mass of a cell for 3D cell culturing. This work illustrates a new dopant-free supramolecular approach, complementary to well-established doping procedures that should facilitate the development of live cell imaging in 3D scaffolding materials.
Remarkable influence of alkyl chain lengths on supramolecular hydrogelation of naphthalene diimide-capped dipeptides
(2015-01-01)
Zhan, Fu-Kai
;
Hsu, Shu-Min
;
Cheng, Hsun
;
Lin, Hsin-Chieh
;
材料科學與工程學系
The influence of aliphatic chain lengths on supramolecular hydrogelation of naphthalene diimide-capped dipeptides is described. The dependence of the gelation pH as a function of chain lengths reveals an inverse linear relationship and the gelation pH values cover a broad range from pH 2 to pH 9. In addition, the presence of a n-octyl tail in the hydrogelator could enhance the ability of self-assembly in dilute solution.
Self-Assembled Peptide-Based Hydrogels as Scaffolds for Proliferation and Multi-Differentiation of Mesenchymal Stem Cells
(2017-04-01)
Wang, Yung-Li
;
Lin, Shih-Pei
;
Nelli, Srinivasa Rao
;
Zhan, Fu-Kai
;
Cheng, Hsun
Fluorenyl-9-methoxycarbonyl (Fmoc)-diphenylalanine (Fmoc-FF) and Fmoc-arginine-glycine-aspartate (Fmoc-RGD) peptides self-assemble to form a 3D network of supramolecular hydrogel (Fmoc-FF/Fmoc-RGD), which provides a nanofibrous network that uniquely presents bioactive ligands at the fiber surface for cell attachment. In the present study, mesenchymal stem cells (MSCs) in Fmoc-FF/Fmoc-RGD hydrogel increase in proliferation and survival compared to those in Fmoc-FF/Fmoc-RGE hydrogel. Moreover, MSCs encapsulated in Fmoc-FF/Fmoc-RGD hydrogel and induced in each defined induction medium undergo in vitro osteogenic, adipogenic, and chondrogenic differentiation. For in vivo differentiation, MSCs encapsulated in hydrogel are induced in each defined medium for one week, followed by injection into gelatin sponges and transplantation into immunodeficient mice for four weeks. MSCs in Fmoc-FF/Fmoc-RGD hydrogel increase in differentiation into osteogenic, adipogenic, and chondrogenic differentiation, compared to those in FmocFF/Fmoc-RGE hydrogel. This study concludes that nanofibers formed by the self-assembly of Fmoc-FF and Fmoc-RGD are suitable for the attachment, proliferation, and multi-differentiation of MSCs, and can be applied in musculoskeletal tissue engineering.
The effect of fluorine on supramolecular hydrogelation of 4-fluorobenzyl-capped diphenylalanine
(2015-01-01)
Wu, Fang-Yi
;
Hsu, Shu-Min
;
Cheng, Hsun
;
Hsu, Ling-Huang
;
Lin, Hsin-Chieh
With the replacement of only one hydrogen atomby fluorine, 4-fluorobenzyl-diphenylalanine was able to form a transparent hydrogel, while benzyl-diphenylalanine did not under similar conditions, indicating the remarkable effect of fluorine on supramolecular hydrogelation.
The role of aromatic side chains on the supramolecular hydrogelation of naphthalimide/dipeptide conjugates
(2018-03-21)
Hsu, Shu-Min
;
Chakravarthy, Rajan Deepan
;
Cheng, Hsun
;
Wu, Fang-Yi
;
Lai, Tsung-Sheng
Herein, the influence of an amino acid side chain on the structural and functional properties of hydrogels has been described. In this study, four new hydrogelators based on the conjugates of dipeptides and naphthalimide (NI) have been designed, synthesized, and examined. Homopeptide 1 (NI-FF) of the phenylalanine residue forms a weak hydrogel or a viscous solution of worm-like micelles under basic conditions. On the other hand, dipeptide conjugates of 2 (NI-FY), 3 (NI-YF), and 4 (NI-YY), containing additional hydroxyl groups as tyrosine residues, can self-assemble into supramolecular hydrogels under physiological pH conditions. UV-vis, IR, and rheological studies clearly indicate the formation and stability of these dipeptide hydrogels. The TEM results revealed that the hydrogels (1-4) self-assembled into a nanofibrous morphology. Furthermore, the cell culture results show that NI-YF has better cell compatibility as compared to NI-FY and NI-YY and thus shows potential to be used as a hydrogel biomaterial. Overall, this study highlights the importance of the structure-hydrogelation relationship and provides new insights into the design of self-assembled peptide amphiphiles.