Tong Cai - Academia.edu (original) (raw)
Papers by Tong Cai
Submitted for the TSF05 Meeting of The American Physical Society Bragg Diffraction as an Indicato... more Submitted for the TSF05 Meeting of The American Physical Society Bragg Diffraction as an Indicator of Hydrogel Crystal Uniformity WILLIAM ESTABROOK, TONG CAI, ZHIBING HU, University of North Texas — This is a study on the use of Bragg diffraction from hydrogel crystals to determine characteristics of growth and uniformity of the crystalline structure. One part of the successful application of hydrogels lies in a better understanding of their crystallization process. This can be done by examining the diffraction pattern generated from projecting a laser on a sample during the stages of crystal formation. The typical spacing in a hydrogel crystal is on the order of hundreds to thousands of nanometers, allowing the utilization of visible spectrum lasers for diffraction studies. William Estabrook University of North Texas Date submitted: 15 Sep 2005 Electronic form version 1.4
Hydrogels composed with poly (N-isopropylacrylamide)-co-Spiropyran acrylamide (PNIPAM-co-SP) were... more Hydrogels composed with poly (N-isopropylacrylamide)-co-Spiropyran acrylamide (PNIPAM-co-SP) were studied for their photo and thermal responsive properties. A mixture of a certain amount of N-isopropylacrylamide monomers, spiropyran acrylamide, crosslinker N, N'-methylene-bis-acrylamide, and photo initiator in acetone/ water solvent was irradiated by UV light to synthesize this PNIPAM-co-SP hydrogel. PNIPAM-co-SP hydrogel was then balanced in water for two days and its property
Poly(N-Isoproylacrylamide) polymer hydrogels possess the special property of a discontinuous volu... more Poly(N-Isoproylacrylamide) polymer hydrogels possess the special property of a discontinuous volumetric phase transition. This phase transition can be induced by external stimuli such as temperature, light, electric or magnetic fields, PH, and others. Of great interest is the functionalization of the gels to external stimuli for faster and more uniform spatial response. An efficient route to functionalization, specifically for termperature
Nanoscale Research Letters, 2009
Biocompatible magnetic nanoparticles hold great therapeutic potential, but conventional particles... more Biocompatible magnetic nanoparticles hold great therapeutic potential, but conventional particles can be toxic. Here, we report the synthesis and alternating magnetic field dependent actuation of a remotely controllable, multifunctional nano-scale system and its marked biocompatibility with mammalian cells. Monodisperse, magnetic nanospheres based on thermo-sensitive polymer network poly(ethylene glycol) ethyl ether methacrylate-co-poly(ethylene glycol) methyl ether methacrylate were synthesized using free radical polymerization. Synthesized nanospheres have oscillating magnetic field induced thermo-reversible behavior; exhibiting desirable characteristics comparable to the widely used poly-N-isopropylacrylamide-based systems in shrinkage plus a broader volumetric transition range. Remote heating and model drug release were characterized for different field strengths. Nanospheres containing nanoparticles up to an iron concentration of 6 mM were readily taken up by neuron-like PC12 p...
Journal of Physics D: Applied Physics, 2009
Biotechnology Journal, 2008
Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispe... more Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispersed nanoparticles. After synthesis, NIPA hydrogel nanoparticles (nanogels) can be labeled by Alexa Fluor ® 488 carboxylic acid, 2,3,5,6-tetrafluorophenyl ester through amine-terminated functional groups. This choice of dye is complementary to other biological labeling methods for in vivo studies. When the nanogel/dye nanoparticles are injected into rabbits, they can be imaged via tissue sectioning and confocal microscopy, while nanoparticle concentration can be determined by fluorescent microplate assays. Time-course persistence of nanoparticles in the circulatory system can be readily tracked by direct assay of plasma and urine samples using 485 nm excitation and 538 emission wavelengths to keep background fluorescence to nearly the same level as that found using an empty well. Depending upon how the nanoparticles are injected, circulatory system concentrations can reach high concentrations and diminish to low levels or gradually increase and gradually decrease over time. Injection in the femoral artery results in a rapid spike in circulating nanogel/dye concentration, while injection into the renal artery results in a more gradual increase.
Biotechnology Journal, 2008
Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispe... more Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispersed nanoparticles. After synthesis, NIPA hydrogel nanoparticles (nanogels) can be labeled by Alexa Fluor ® 488 carboxylic acid, 2,3,5,6-tetrafluorophenyl ester through amine-terminated functional groups. This choice of dye is complementary to other biological labeling methods for in vivo studies. When the nanogel/dye nanoparticles are injected into rabbits, they can be imaged via tissue sectioning and confocal microscopy, while nanoparticle concentration can be determined by fluorescent microplate assays. Time-course persistence of nanoparticles in the circulatory system can be readily tracked by direct assay of plasma and urine samples using 485 nm excitation and 538 emission wavelengths to keep background fluorescence to nearly the same level as that found using an empty well. Depending upon how the nanoparticles are injected, circulatory system concentrations can reach high concentrations and diminish to low levels or gradually increase and gradually decrease over time. Injection in the femoral artery results in a rapid spike in circulating nanogel/dye concentration, while injection into the renal artery results in a more gradual increase.
Submitted for the TSF05 Meeting of The American Physical Society Bragg Diffraction as an Indicato... more Submitted for the TSF05 Meeting of The American Physical Society Bragg Diffraction as an Indicator of Hydrogel Crystal Uniformity WILLIAM ESTABROOK, TONG CAI, ZHIBING HU, University of North Texas — This is a study on the use of Bragg diffraction from hydrogel crystals to determine characteristics of growth and uniformity of the crystalline structure. One part of the successful application of hydrogels lies in a better understanding of their crystallization process. This can be done by examining the diffraction pattern generated from projecting a laser on a sample during the stages of crystal formation. The typical spacing in a hydrogel crystal is on the order of hundreds to thousands of nanometers, allowing the utilization of visible spectrum lasers for diffraction studies. William Estabrook University of North Texas Date submitted: 15 Sep 2005 Electronic form version 1.4
Hydrogels composed with poly (N-isopropylacrylamide)-co-Spiropyran acrylamide (PNIPAM-co-SP) were... more Hydrogels composed with poly (N-isopropylacrylamide)-co-Spiropyran acrylamide (PNIPAM-co-SP) were studied for their photo and thermal responsive properties. A mixture of a certain amount of N-isopropylacrylamide monomers, spiropyran acrylamide, crosslinker N, N'-methylene-bis-acrylamide, and photo initiator in acetone/ water solvent was irradiated by UV light to synthesize this PNIPAM-co-SP hydrogel. PNIPAM-co-SP hydrogel was then balanced in water for two days and its property
Poly(N-Isoproylacrylamide) polymer hydrogels possess the special property of a discontinuous volu... more Poly(N-Isoproylacrylamide) polymer hydrogels possess the special property of a discontinuous volumetric phase transition. This phase transition can be induced by external stimuli such as temperature, light, electric or magnetic fields, PH, and others. Of great interest is the functionalization of the gels to external stimuli for faster and more uniform spatial response. An efficient route to functionalization, specifically for termperature
Nanoscale Research Letters, 2009
Biocompatible magnetic nanoparticles hold great therapeutic potential, but conventional particles... more Biocompatible magnetic nanoparticles hold great therapeutic potential, but conventional particles can be toxic. Here, we report the synthesis and alternating magnetic field dependent actuation of a remotely controllable, multifunctional nano-scale system and its marked biocompatibility with mammalian cells. Monodisperse, magnetic nanospheres based on thermo-sensitive polymer network poly(ethylene glycol) ethyl ether methacrylate-co-poly(ethylene glycol) methyl ether methacrylate were synthesized using free radical polymerization. Synthesized nanospheres have oscillating magnetic field induced thermo-reversible behavior; exhibiting desirable characteristics comparable to the widely used poly-N-isopropylacrylamide-based systems in shrinkage plus a broader volumetric transition range. Remote heating and model drug release were characterized for different field strengths. Nanospheres containing nanoparticles up to an iron concentration of 6 mM were readily taken up by neuron-like PC12 p...
Journal of Physics D: Applied Physics, 2009
Biotechnology Journal, 2008
Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispe... more Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispersed nanoparticles. After synthesis, NIPA hydrogel nanoparticles (nanogels) can be labeled by Alexa Fluor ® 488 carboxylic acid, 2,3,5,6-tetrafluorophenyl ester through amine-terminated functional groups. This choice of dye is complementary to other biological labeling methods for in vivo studies. When the nanogel/dye nanoparticles are injected into rabbits, they can be imaged via tissue sectioning and confocal microscopy, while nanoparticle concentration can be determined by fluorescent microplate assays. Time-course persistence of nanoparticles in the circulatory system can be readily tracked by direct assay of plasma and urine samples using 485 nm excitation and 538 emission wavelengths to keep background fluorescence to nearly the same level as that found using an empty well. Depending upon how the nanoparticles are injected, circulatory system concentrations can reach high concentrations and diminish to low levels or gradually increase and gradually decrease over time. Injection in the femoral artery results in a rapid spike in circulating nanogel/dye concentration, while injection into the renal artery results in a more gradual increase.
Biotechnology Journal, 2008
Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispe... more Hydrogels made of N-isopropylacrylamide (NIPA) can be synthesized in the form of highly monodispersed nanoparticles. After synthesis, NIPA hydrogel nanoparticles (nanogels) can be labeled by Alexa Fluor ® 488 carboxylic acid, 2,3,5,6-tetrafluorophenyl ester through amine-terminated functional groups. This choice of dye is complementary to other biological labeling methods for in vivo studies. When the nanogel/dye nanoparticles are injected into rabbits, they can be imaged via tissue sectioning and confocal microscopy, while nanoparticle concentration can be determined by fluorescent microplate assays. Time-course persistence of nanoparticles in the circulatory system can be readily tracked by direct assay of plasma and urine samples using 485 nm excitation and 538 emission wavelengths to keep background fluorescence to nearly the same level as that found using an empty well. Depending upon how the nanoparticles are injected, circulatory system concentrations can reach high concentrations and diminish to low levels or gradually increase and gradually decrease over time. Injection in the femoral artery results in a rapid spike in circulating nanogel/dye concentration, while injection into the renal artery results in a more gradual increase.