Browsing by Author "Chen, Jem-Kun"

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Association of poly(N-isopropylacrylamide) containing nucleobase multiple hydrogen bonding of adenine for DNA recognition
(2013-04-15)
Yang, Hsiu-Wen
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Chen, Jem-Kun
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Cheng, Chih-Chia
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Kuo, Shiao-Wei
;
應用化學系
In this study we used the poly(N-isopropylacrylamide) (PNIPAAm) as a medium to generate PNIPAAm-adenine supramolecular complexes. A nucleobase-like hydrogen bonding (NLHB) between PNIPAAm and adenine was found that changed the morphology, crystalline structure, and temperature responsiveness of PNIPAAm microgels relatively to the adenine concentrations. With increasing the adenine concentration, the PNIPAAm-adenine supramolecular complexes gradually altered their morphologies from microgel particles to thin film structures and suppressed the thermodynamical coil-to-globule transition of PNIPAAm because of the NLHB existed between the PNIPAAm amide and ester groups and the adenine amide groups (C=O center dot center dot center dot H-N and N-H center dot center dot center dot N-R), verified by FTIR spectral analysis. NLHB was also diverse and extensive upon increasing the temperature; therefore, the thermoresponsive behavior of the complexes was altered with the NLBH intensity, evaluated by the inter-association equilibrium constant (K-a) above and below their LCST. Therefore, PNIPAAm can be as a medium to recognize adenine in various concentrations, which could potentially be applied in DNA recognition. (C) 2013 Elsevier B.V. All rights reserved.
Bioinspired assembly of functional block-copolymer nanotemplates
(2013)
Lin, I. -Hong
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Cheng, Chih-Chia
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Chuang, Wei-Tsung
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Chen, Jem-Kun
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Jeng, U. -Ser
A new concept on bioinspired assembly of functional diblock copolymers, capable of forming different microstructures through nucleobase-induced supramolecular interactions, has been explored. In this paper, a new series of uracil-functionalized poly(epsilon-caprolactone)-b-(4-vinylbenzyl uracil)s (PCL-b-PVBU) have been prepared which exhibit a high self-complementary ability in solution and solid states owing to the formation of uracil-uracil pairs by induced hierarchical self-assembly. The ordered morphologies of PCL-b-PVBU diblock copolymers changed from a lamellar, hexagonally packed cylinder to a sphere with respect to the content of the hydrogen bond segment. Moreover, we further show that the PCL segment could be easily extracted by enzymatic degradation, leading to a cylinder porous structure of long-range order, which gives a facile method for the fabrication of uracil-functionalized nanotemplates. In addition, bio-complementary PCL-b-PVBU/9-hexadecyladenine (AC16) hierarchical supramolecular complexes formed through strong cooperative hydrogen bonding between the uracil group of PVBU and the adenine group of A-C16. When the mixing ratios of PCL-b-PVBU/AC16 differ from the stoichiometric ratio, these complexes self-assemble into well-ordered lamellar and hexagonal structures; the changing morphology at different AC16 loadings reveals that the molecular structures of the PCL-b-PVBU/AC16 complexes are readily tailored.
Bioinspired hole-conducting polymers for application in organic light-emitting diodes
(2012)
Cheng, Chih-Chia
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Chu, Yu-Lin
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Huang, Pei-Hsiu
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Yen, Ying-Chieh
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Chu, Chih-Wei
A novel uracil-functionalized poly(3-thiophene) as a hole-injecting/transporting layer in an organic light-emitting device is able to form physical crosslinkages resulting in high thermal stability, non-corrosion, excellent hole injection/transport and electron-blocking capabilities in the solid state, and it achieves up to 10 times higher performance than that of conventional poly(3-thiophene)s under similar experimental conditions.
Bioinspired supramolecular fibers for mercury ion adsorption
(2013)
Wang, Yeh-Sheng
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Cheng, Chih-Chia
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Chen, Jem-Kun
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Ko, Fu-Hsiang
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Chang, Feng-Chih
Anovel photo-cross-linkable nanofiber based on a uracil-functionalized polymer, poly[ 1-(4-vinylbenzyl uracil)] (PVBU), was prepared using the electrospinning technique. This PVBU nanofiber can be converted into a covalent network nanofiber through exposure to UV light at a wavelength of 254 nm. This PVBU nanofiber is able to distinguish and selectively remove mercury ions (Hg2+) from other metal ions in aqueous solution. The maximum Hg2+ adsorption capacity of the PVBU nanofiber is 543.9 mg g(-1), which is significantly higher than that of cyclic imide derivatives. The improved adsorption of Hg2+ allows a detection limit of less than 1 ppm, which has rarely been achieved for Hg2+ sensing. Furthermore, the PVBU fiber can be reused for 10 consecutive cycles using 1.0 M HCl treatment. This new material has significant potential for the simultaneous detection and separation of Hg2+ in environmental and industrial fields.
Characterization of patterned poly(methyl methacrylate) brushes under various structures upon solvent immersion
(2009-10-15)
Chen, Jem-Kun
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Hsieh, Chih-Yi
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Huang, Chih-Feng
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Li, Po-min
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應用化學系
In this paper we describe a graft polymerization/solvent immersion method for generating various patterns of polymer brushes. We used a very-large-scale integration (VLSI) process and oxygen plasma system to generate well-defined patterns of polymerized methyl methacrylate (MMA) on patterned Si(1 0 0) surfaces through atom transfer radical polymerization (ATRP). After immersion of wafers presenting lines of these PMMA brushes in water and tetrahydrofuran, we observed mushroom-and brush-like regimes through grafting densities and surface coverages, respectively, for the PMMA brushes with various pattern resolutions. In the mushroom-like regime, the distance between lines of PMMA brushes was smaller than that of the lines patterned lithographically on the wafer; in the brush-like regime, this distance was approximately the same. This new strategy allows polymer brushes to be prepared through graft polymerization and then have their patterns varied through solvent immersion. (C) 2009 Elsevier Inc. All rights reserved.
Electrorheological Operation of Low-/High-Permittivity Core/Shell SiO2/Au Nanoparticle Microspheres for Display Media
(2012-10-01)
Li, Chung-Lin
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Chen, Jem-Kun
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Fan, Shih-Kang
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Ko, Fu-Hsiang
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Chang, Feng-Chih
In this study, we synthesized core/shell structures comprising monodisperse 3-mu m SiO2 microspheres and gold nanoparticles (AuNPs, ca. 6.7 nm) as the core and shell components, respectively. Using a layer-by-layer cross-linking process with a dithiol cross-linking agent, we prepared low-permittivity AuNP-encapsulated higa-permittivity SiO2 core/shell microspheres with variable AuNP shell thicknesses. The dispersivity of the microspheres in solution was enhanced after grafting poly(ethylene glycol) monomethyl ether thiol (PEG-SH) onto the AuNP layer on the SiO2 microspheres. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images revealed sesame ball-like structures for these SiO2@AuNP@PEG microspheres. We encapsulated aqueous dispersions of these SiO2@AuNP microspheres into sandwich structured displays (SSDs) to investigate their electrorheological properties, observing reversibly electroresponsive transmittance that is ideally suited for display applications. Increasing the thickness of the AuNP layer dramatically enhanced the stringing behavior of the SiO2 microspheres, resulting in increased transmittance of the SSD. The response time of the electroresponsive electrorheological fluids also decreased significantly after modifying the SiO2 with the AuNP layers. The effective permittivities of these composites could be predicted from the real (epsilon) and imaginary (epsilon) parts of the Clausius-Mossotti formalism.
Fabrication of biomimetic device with PS-b-PNIPAAm copolymer pillars mimicking a gecko foot pad
(2012-11-01)
Chen, Jem-Kun
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Wang, Jing-Hong
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Cheng, Chih-Chia
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Ko, Fu-Hsiang
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應用化學系
Inspired by the climbing aptitude of geckos, a gecko's foot pad can alternately attach to and detach from almost any kind of surface. We firstly fabricated a multi-layer thin film with electrodes as a thermal device that could adjust the surface temperature by applying voltage. We sequentially used very-large-scale integration (VLSI) process and atom-transfer radical-polymerization (ATRP) process to generate well-defined pillar patterns of polymerized styrene as seta analogues and successively grafted n-isopropylacrylamide (NIPAAm) as thermally responsive terminating of the pillars to mimic the configuration of a real gecko's foot pad. Our fabrication strategy exploits surface textures of polystyrene (PS) and thermally responsive terminating of PNIPAAm, which could generate alternately ca. 88.1 and 11.3 nN of adhesive force at 0.2 and 2 V of applying voltage, respectively. The results indicate that the adjustable adhesive ability of the copolymer brushes could approach the climbing aptitude of a gecko much more closely through voltage tuning. The advantage of the processing strategy described here is the potential to fabricate a device of an artificial foot pad to mimic the climbing aptitude of geckos vividly. (C) 2012 Elsevier B.V. All rights reserved.
Fabrication of two-dimensional photonic crystals of tethered polyvinyltetrazole on silicon surfaces for visualization in Cu2+ ion sensing
(2017-04)
Zeng, Jun-Ru
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Cheng, Chih-Chia
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Chang, Chi-Jung
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Huang, Chi-Hsien
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Chen, Jem-Kun
We grafted polyacrylonitrile (PAN) from a flat silicon substrate via atom transfer radical polymerization (ATRP) as a bottom layer. Fabrication processes, involving very-large-scale integration (VLSI) and reactive ion etching (RIE), are sequentially used to generate 800 nm-diameter hole array of tethered PAN layer as two-dimensional photonic crystals (2DPCs). The tethered PAN 2DPCs were then subjected to a cyano-totetrazole conversion reaction to generate tethered polyvinyltetrazole (PVT) 2DPCs. Fabricating hole array could be regarded as air filling within the PVT layer, resulted in a significant decrease of effective refractive index of the PVT film. In addition, the adsorption of Cu2+ ions to the tetrazolyl groups was highly selective in solutions also containing Na+, K+, Ca2+, and Mg2+ ions. After absorption of Na+, K+, Ca2+, Mg2+, Fe3+, and Zn2+ ions, the tethered PVT 2DPC displayed insignificant changes in its effective refractive index; in contrast, upon absorbing Cu2+ ions, a dramatic change in effective refractive index occurred, resulting in a color change from red to green, observable to the naked eye along an incident angle of 30-40 degrees. The holes dimension within the array of tethered PVT shrunk after absorption of Cu2+ ions leading to a predominated blue-shift in the diffractive peak position. The tethered PVT 2DPC-based assay exhibited high sensitivity and selectivity in an experimentally simple setup for visualization in Cu2+ ion sensing.(C) 2016 Elsevier Ltd. All rights reserved.
Functionalized graphene nanomaterials: new insight into direct exfoliation of graphite with supramolecular polymers
(2016-01-01)
Cheng, Chih-Chia
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Chang, Feng-Chih
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Wang, Jui-Hsu
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Chen, Jem-Kun
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Yen, Ying-Chieh
A novel urea-cytosine end-capped polypropylene glycol (UrCy-PPG) can self-assemble into a long-range ordered lamellar microstructure on the surface of graphene, due to the strong specific interactions between UrCy-PPG and graphene. In addition, the graphene composite produced exhibits a high conductivity (similar to 1093 S m(-1)) with a dramatic thermo-responsive ON/OFF resistance-switching behavior (10 consecutive cycles).
High-efficiency self-healing materials based on supramolecular polymer networks
(2015-01-01)
Cheng, Chih-Chia
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Chang, Feng-Chih
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Chen, Jem-Kun
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Wang, Tzu-Yin
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Lee, Duu-Jong
Supramolecular polymers, a combination of secondary interactions and a polymer material, can be used to control supramolecular self-assembly in a polymeric matrix; these materials exhibit unique stimuli-responsiveness and self-healing properties making them highly attractive for various applications. Herein, we developed a novel supramolecular poly-urea containing a urea-cytosine (UrCy) quadruple hydrogen bonding moiety that undergoes a dynamic healing mechanism, "supramolecular polymer networks (SPN)", and rapidly repairs after damage under mild conditions. Interestingly, this newly-developed material can also self-heal at room temperature without external intervention, as evidenced by repeated restoration of mechanical properties. Given its simplicity, efficiency and reliability, this material offers a unique paradigm for developing SPN-based self-healing materials.
Highly efficient drug delivery systems based on functional supramolecular polymers: In vitro evaluation
(2016-03-15)
Cheng, Chih-Chia
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Chang, Feng-Chih
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Kao, Wan-Yi
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Hwang, Shiaw-Min
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Liao, Li-Chuan
The novel concept of modifying and enhancing the properties of existing functional micelles through self-complementary interactions has significant potential. In this study, a practical approach to living polymerization of functionalized thermoresponsive monomers enabled the incorporation of self constituted multiple hydrogen bonded groups into micelles that have potential as supramolecular drug-delivery systems. Phase transitions and morphological studies in aqueous solution showed that the microstructure can be controlled to achieve well-defined vesicle-like micelles with respect to the strength of the hydrogen bond segment. Thus, the resulting micelles have a very low critical micellization concentration and very high loading capacity (16.1%), making the loading process extremely stable and efficient. Incorporation of the anticancer drug doxorubicin (DOX) affected the micellization process in aqueous solution and enabled fine-tuning of drug loading and precise control of drug release rate with excellent sensitivity. Release studies in vitro showed that DOX-loaded micelles exerted dose dependent cytotoxicity against human liver carcinoma (HepG2) cells at the physiological temperature of 37 degrees C. In addition, DOX-loaded micelles were efficiently endocytosed by the cancer cells, which may enable the micelles to serve as suitable vehicles for effective delivery of anticancer drugs to primary tumors and metastatic disease. This newly developed material may provide a potential route towards next-generation drug delivery vehicles. Statement of Significance A breakthrough innovation in water-based thermo-responsive polymers has enabled significant progress in developing smart stimuli-responsive nanocarriers by generating novel "supramolecular polymeric micelles" via self-complementary hydrogen-bonding interactions. These newly developed micelles exhibit extremely high micellar stability and drug loading capacity (up to 16%), excellent thermo-responsive behavior and precise control of drug release rate due to hydrogen-bond-induced physical cross-linking. In addition, doxorubicin-loaded micelles were efficiently endocytosed by the cancer cells, which allows them to serve as suitable vehicles for effective delivery of anticancer drugs to primary tumors and metastatic disease. Thus, this work provides a potential route for the development of next generation multifunctional nanocarriers that have improved safety and to increase the therapeutic efficacy of anticancer therapy. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Immobilization of layered double hydroxides in the fluidic system for nanoextraction of specific DNA molecules
(2008-02-04)
Chen, Jem-Kun
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Chan, Chia-Hao
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Chang, Feng-Chih
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應用化學系
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Department of Applied Chemistry
The purpose of this study was to immobilize inorganic layered double hydroxides (LDHs) on the poly(methylmethacrylate) substrate as the media to extract the specific DNA molecules through fluidic system to enhance the efficiency of extract specific DNA molecules from extremely low concentration in sample solution. LDH immobilized through solvent swelling and plasma treatment on the polymer surface captured the specific DNA molecules lysed from Escherichia coli (E. coli) cells as the target DNA molecules with 2x10(-4) g/l of concentration in sample solution mixed biomacromolecules lysed from human blood. The encapsulated DNA molecules released through dissolving of LDHs by slight acid (pH=4-5) solution then amplified by polymerase chain reaction (PCR) process through the primers for E. coli cells. The DNA molecules amplified by PCR process were characterized by gel electrophoresis to recognize the existence of E. coli cells. The results show that immobilized LDHs could be regarded as the specific DNA detector for rapid disease diagnosis through fluidic system. (C) 2008 American Institute of Physics.
Immobilization of Layered double Hydroxides in the Fluidic System for Nanoextraction of Specific DNA Molecules
(2010-01-01)
Chen, Jem-Kun
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Chan, Chia-Hao
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Chang, Feng-Chih
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應用化學系
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Department of Applied Chemistry
The purpose of this study was to immobilize inorganic layered double hydroxides (LDHs) on the poly(methylmethacrylate) (PMMA) substrate as the media to extract the specific DNA molecules through fluidic system to enhance the efficiency of extract specific DNA molecules from extreme low concentration in sample solution. The encapsulated DNA molecules released through dissolve of LDHs by slight acid (PH=4-5) solution then amplified by polymerase chain reaction (PCR), process through the primers for E. coli cells. The results show that immobilized LHDs could be regarded as the specific DNA detector in the sample solution mixed biomacromolecules for rapid disease diagnosis through fluidic system.
Label-free detection of DNA hybridization using nanopillar arrays based optical biosensor
(2014-04-01)
Chen, Jem-Kun
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Zhou, Gang-Yan
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Chang, Chi-Jung
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Cheng, Chih-Chia
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應用化學系
In this study we fabricated nanopillar arrays (NPLAs) of silicon, through a process involving very-large-scale integration and reactive ion etching, for use as two-dimensional periodic relief gratings on silicon surfaces. Oligonucleotides were successively immobilized on the pillar surface, allowing the system to be used as an optical detector specific for the targeted single-stranded DNAs (ssDNAs). The surfaces of the oligonucleotides-modified NPLAs underwent insignificant structural changes, but upon hybridizing with target ssDNA, the NPLAs underwent dramatic changes in terms of their pillar scale. Binding of the oligonucleotides to the NPLA occurred in a way that allowed them to retain their function and selectively bind the target ssDNA. We evaluated the performance of the sensor by capturing the target ssDNA on the NPLA and measuring the effective refractive index (n(eff)). The binding of the target ssDNA species to the NPLA resulted in a color change from pure blue to red, observable by the naked eye at an angle of 15 degrees. Moreover, we used effective medium theory to calculate the filling factors inside the NPLA and, thereby, examine the values of n(eff) during the structural changes of the NPLA. Accordingly, these new films have potential applications as label-free optical biosensors. (C) 2013 Elsevier B. V. All rights reserved.
Liquid Lenses and Driving Mechanisms: A Review
(2012)
Chiu, Cheng-Pu
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Chiang, Tsai-Jung
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Chen, Jem-Kun
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Chang, Feng-Chih
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Ko, Fu-Hsiang
In this paper, we discuss liquid lenses driven by various mechanisms. By properly designing the device structure and choosing the optimal materials, the liquid lenses offer great potential for practical uses. The driving mechanism dictates the application and performance of the liquid lenses. Here we categorize the driving mechanisms into mechanical and electrical ones. In general, mechanical driving with an elastic membrane and an external pump drives liquids in a cavity by controlling the hydraulic pressure. The mechanical driving method can be applied to most of the liquids, but the application of the electrical driving method would be limited by the conductivity or the permittivity of the liquids. Therefore, the properties of the different liquids, e. g., dielectric liquids, liquid crystal molecules, and conductive liquids, deeply affect the mechanism we may choose to realize a liquid lens. Among various electrical methods, dielectrophoresis (DEP), electrostatic forces, and electrowetting-on-dielectric (EWOD) are emphasized here for driving dielectric liquids, liquid crystal molecules, and conductive liquids, respectively. DEP deforms the liquid lenses when the permittivities are different between the liquid and the medium. Electrostatic force orients the liquid crystal molecules to follow the applied electric field. Electrowetting-driven liquid lenses change their focal lengths by altering the contact angle. Here we show the designs and the structures of liquid lenses to describe their mechanisms, performances and feasibilities. It is worth mentioning that the liquid lenses using electrowetting have been commercialized. No moving parts would be the most important reason to use electrical manipulations rather than mechanical ones. (C) Koninklijke Brill NV, Leiden, 2011
Low-surface-free-energy polybenzoxazine/polyacrylonitrile fibers for biononfouling membrane
(2013-01-08)
Kao, Tzu-Hao
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Chen, Jem-Kun
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Cheng, Chih-Chia
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Su, Ching-Juan
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Chang, Feng-Chih
We blended poly(3-phenyl-3,4-dihydro-2H-1,3-benzoxazine) (PBA) into polyacrylonitrile (PAN) to generate low-surface-free-energy fibers without fluorine and silicon elements for electrospinning. Liquid-state BA at room temperature can be solidified in electrospinning process using PAN as a medium through their miscible behavior. Results indicate that the mixing below 50 wt% BA into PAN matrix for electrospinning has no significant dropping beads, indicated a miscible PAN/BA system. Above 70 wt% BA in PAN solution could not be solidified completely after electrospinning, revealed apparent beaded fibers. The PAN/PBA blend fibers, obtained after curing at 300 degrees C, generated a superhydrophobicity because of the low-surface-free-energy PBA. In addition, laser scanning confocal microscope (LSCM) measurements were included to determine the relative amount of antibody that adsorbed to these PAN/PBA fibers to examine the biofouling-resistant property. The results showed an obviously decreased protein adsorption with increasing PBA fraction. The correlations between PAN and PBA would provide insight into the designing and developing of low-surface-free-energy fibers without fluorine and silicon elements to improve biofouling-resistant property. (C) 2012 Elsevier Ltd. All rights reserved.
Microwave-assisted Electroless Deposition of Silver Nanoparticles onto Multiwalled Carbon Nanotubes
(2012-05-01)
Wu, Chung-Shu
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Lee, Chung-Yang
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Chen, Jem-Kun
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Kuo, Shiao-Wei
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Fan, Shih-Kang
In this study, an efficient microwave-assisted self-organization of silver nanoparticles onto multiwalled carbon nanotubes (MWCNTs) is proposed. Silver nanoparticles anchor onto the surface of MWCNTs through self-assembly at the reaction condition of 160 degrees C. We mixed the MWCNTs with saturated silver nitrate/nitric acid solution, without adding a reductant or stabilizer, and then heated them in the closed microwave heating system. The oxidizing conditions create active sites on the surface of MWCNTs and the silver nanoparticles spontaneously align at these sites through electroless deposition. The growing nanoparticles have fcc structures and their density increases upon increasing the reaction time.
Miscibility and hydrogen-bonding behavior in organic/inorganic polymer hybrids containing octaphenol polyhedral oligomeric silsesquioxane
(2008-09-04)
Yen, Ying-Chieh
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Kuo, Shiao-Wei
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Huang, Chih-Feng
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Chen, Jem-Kun
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Chang, Feng-Chih
In this study, we Investigated the miscibility behavior and mechanism of interaction of poly(methyl mechacrylate) (PMMA), poly(vinyl pyrrolidone) PVP, and PMMA-co-PVP blends with octa(phenol)octasilsequioxane (OP-POSS). For the PMMA/OP-POSS binary blend, the value of the association constant (K(A) = 29) was smaller than that in the poly(vinyl phenol) (PVPh)/PMMA (K(A) = 37.4) and ethyl phenol (EPh)/PMMA (K(A) = 101) blend systems, implying that the phenol groups of the OP-POSS units in the PMMA/OP-POSS blends interacted to a lesser degree with the C=O groups of PMMA than they did in the other two systems. In addition, the ionic conductivity of a LiClO(4)/PMMA-co-PVP polymer electrolyte was increased after blending with OP-POSS.
New bioinspired hole injection/transport materials for highly efficient solution-processed phosphorescent organic light-emitting diodes
(2015-04-01)
Cheng, Chih-Chia
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Chu, Yu-Lin
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Chang, Feng-Chih
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Lee, Duu-Jong
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Yen, Ying-Chieh
A new concept to supramolecular assembly of existed functional polymers, capable of forming network-like organizational clusters through multiple hydrogen-bonding interactions has been exploited. In this paper, a new adenine-based poly(triphenylamine-carbazole) (PTC-A) has been prepared which exhibits a high self-complementary ability in solution and solid states owing to the formation of adenine-adenine (A-A) pairs by induced hierarchical self-assembly. Comparing with uracil-substituted PTC sample (PTC-U), PTC-A presents a much higher thermal stability, electrochemical stability and solvent-resistance ability due to the formation of the more stable physically cross-linking structure. When the PTC-A is utilized as a hole injection/transport layer in a trilayer OLED device, a remarkable improvement in performance relative to the control PTC and PTC-U under similar experimental conditions has been achieved. Further comparison with a control device using a conventional PEDOT:PSS, the efficiency of the solution-processed phosphorescent PLED device with PTC-A is significantly higher than those of PTC-U and PEDOT: PSS-based devices. Thus, PTC-A represents the next-generation hole injection/transport material for high efficiency LED device and low-cost fabrication process. (C) 2015 Elsevier Ltd. All rights reserved.
Nucleobase-Functionalized Supramolecular Micelles with Tunable Physical Properties for Efficient Controlled Drug Release
(2016-10)
Cheng, Chih-Chia
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Lin, I-Hong
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Chen, Jem-Kun
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Liao, Zhi-Sheng
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Huang, Jyun-Jie
Complementary nucleobase-functionalized polymeric micelles, a combination of adenine-thymine (A-U) base pairs and a blend of hydrophilic-hydrophobic polymer pairs, can be used to construct 3D supramolecular polymer networks; these micelles exhibit excellent self-assembly ability in aqueous solution, rapid pH-responsiveness, high drug loading capacity, and triggerable drug release. In this study, a multi-uracil functionalized poly(epsilon-caprolactone) (U-PCL) and adenine end-capped difunctional oligomeric poly(ethylene glycol) (BA-PEG) are successfully developed and show high affinity and specific recognition in solution owing to dynamically reversible A-U-induced formation of physical cross-links. The U-PCL/BA-PEG blend system produces supramolecular micelles that can be readily adjusted to provide the desired critical micellization concentration, particle size, and stability. Importantly, in vitro release studies show that doxorubicin (DOX)-loaded micelles exhibit excellent DOX-encapsulated stability under physiological conditions. When the pH value of the solution is reduced from 7.4 to 5.0, DOX-loaded micelles can be rapidly triggered to release encapsulated DOX, suggesting these polymeric micelles represent promising candidate pH-responsive nanocarriers for controlled-release drug delivery and pharmaceutical applications.