PH And Temperature-Responsive P(DEA-co-MAA) Bionic Materials Were Synthesized And Effected With Some Medical-active Compound

In this paper, a series of pH-sensitive and temperature-responsive copolymers andhydrogels were prepared by free radical polymerization. The swelling behavior andpH sensitivity of the copolymers and hydrogels was studied in detail.1. A series of pH and temperature-responsive (N,N-diethylacrylamide-co-methylacrylicacid) copolymers were synthesized by radical copolymerization andcharacterized by elemental analysis, Fourier-transform infrared (FT-IR), nuclearmagnetic resonance (NMR) ¹H, ¹³C and LLS. The effects of salt and pH on the phasetransition behaviors of the copolymers were investigated by UV. With increasingNaCl concentration, significant salt effects on their phase transition behaviors wereobserved. UV spectroscopic studies showed that the phase transition became fasterwith increasing NaCl concentration. The LCST values were found to increase slightlyinitially with increasing MAA content; further increase MAA content induced theLCST to decrease. In addition, the phase transition behaviors of copolymers weresensitive to pH. The pH and temperature sensitivity of these copolymers would makean interesting drug delivery system.2. 2-((4-methoxyphenoxy) carbonyl) benzoic acid, 2-(1-methoxyvinyl) benzoic acidand their complexes LnL₂(OH)·3H₂O(Ln=La(â…¢), Eu(â…¢), Tb(â…¢)) andCu₂L₄(DMF)(CH₃OH)·CH₃OH, were synthesized and characterized by means ofelemental analysis, FTIR, ¹H NMR. And the Cu complexesdissolved in water, methol and ethanol, which give a support with the research of theantitumor activity in vitro. At the same time, the Cu complexes was added in thecopolymer solution, the result show that the LCST of the copolymer was decreasedwith the Cu complexes added, the DLS and fluorescence probe show that the chain ofthe copolymers were effected by the Cu complexes. All of this have a good begin toresearch the function between the Cu complexes and biopolymer. The luminescencespectra of Eu(â…¢) and Tb(â…¢) complexes in solid state were also studied. The strongluminescence emitting peaks at 615 nm for Eu(â…¢) complexes and 546 nm for Tb(â…¢) complexes can be observed, which could be attributed to the characteristic emissionsof Eu(â…¢) and Tb(â…¢) ions, this indicated that the ligands of HL^â… and HL^â…¡are goodorganic chromophore to absorb and transfer energy to metal ions. This providedexperimentations and information to find the steady and brightness luminescencematerials.3. In aqueous solution, a series of pH and temperature-responsive copolymerhydrogels were synthesized by radical copolymerization and characterized. The swellratio of the hydrogels was changed by the MAA content, pH and temperature. Andthen, the drug delivery system of the L-tryptophan in the drug-loaded hydrogelsshown that the process of the drug release was an complex course, which was affectedby pH and the composing of the copolymer. And the studies of the threesulfanilamides with different substitutes showed that there was no different in thereleased curve at 37℃. All of this showed that the copolymer hydrogels were auseableness carrier of drugs in the future.4. A series of complexes of poly(N,N-diethylacrylamide-co-methacrylic acid)(P(DEA-co-MAA)) with Ln(â…¢) (Ln = La, Eu, Tb) were synthesized andcharacterized by X-ray diffraction, elemental analysis, FT-IR and TG-DTA. Theluminescence spectra of Eu(â…¢) and Tb(â…¢) complexes in solid state were also studied.The complexes exhibit strong characteristic luminescence of Eu(â…¢) and Tb(â…¢) ions,while the luminescence intensity depend on the content of DEA and Ln(â…¢) ions: thechange of the relative luminescence intensity is not obvious when the lanthanide ioncontent is decreased.The possible reason is that more energy could transfer from DEAto Ln(â…¢) ions with the decrease of lanthanide ions content and the increase of DEAcontent.