Font Size: a A A

A "Ship-In-A-Bottle" Approach To Synthesis Of Immobilized Cyclodextrin-porphyrins In Hollow Mesoporous Molecular Sieves HMSS

Posted on:2016-05-15Degree:MasterType:Thesis
Country:ChinaCandidate:X X ZhouFull Text:PDF
GTID:2181330467497160Subject:Microbial and Biochemical Pharmacy
Abstract/Summary:PDF Full Text Request
In1960s, scientists used synthetic macromolecules to simulate the structure,characteristic and action principle of enzymes. Immobilized enzymes are one makescatalytic action in a certain space and can be used in a repeated and continuousmanner. However, traditional immobilized enzymes use solid materials to boundenzymes to a certain space which will limit the conformational change of enzymes,affect the substrate recognition and decrease the activity of enzymes.This work used hydrothermal synthetic HMSS as carrier and assembledcyclodextrin-zinc porphyrin in hollow mesoporous pore through “ship-in-a-bottle”.We demonstrated that porphyrin complexes was assembled in hollow mesoporoussilica sieve via many characterization techniques such as X-ray diffraction, nitrogenadsorption, fourier transform infrared spectroscopy, thermogravimetric analysis,transmission electron microscope and scanning electron microscope. Compared withenzymes outside, catalytic experiments of H2O2oxidation of Vc was performed to testthe activity of immobilized cyclodextrin-zinc porphyrin in HMSS and the mechanismof different activity was also analysed. Moreover, we investigated the advantages anddisadvantages of immobilized enzymes in a “ship-in-a-bottle” manner, opening newstandpoints for further developments of the delivery system.Firstly, hollow mesoporous molecular sieve HMSS materials were successfullysynthesized withtemplate CTAB by hydrothermal method. In the cytotoxicity study ofmolecular sieve HMSS, At high concentrations (>10ug/ul) case, hollow mesoporousmolecular sieve (HMSS) had strong toxicity and morphological abnormalities to thecells, it inhibited cell growth in5hours and the inhibition rate reached100%, all cellswere dead after24h.However,an mediumconcentration(>5ug/ul.<10ug/ul) and lowconcentration (<5ug/ul) case, molecular sieve samples in DMEM medium were nottoxic to cells and had normal cell morphology.Secondly, metal porphyrin derivatives and beta-cyclodextrin were synthesized byAdler method. The structure was characterized by infrared spectroscopy,provingsuccessful synthesis. The cyclodextrin zinc porphyrin complexes was synthesized by“ship-in-a-bottle”method. Compared with traditional fixation methods,it does not need fixed crosslinking agent. And the mimic enzymesynthesized canmake free movement in the cavity of hollow molecular sieve. It is advantageous to theidentification of substrate and the conformational change of enzyme, resulting inhigher catalytic activity and repeated use.Finally, the experiment of Vc oxidation by H2O2verified the catalytic activity andreuse value of cyclodextrin zinc porphyrins carried by HMSS. And he catalyticactivity of the enzymereached53.18%on average, showing relatively high catalyticactivity and good stability. So the cyclodextrin zinc porphyrins is synthesizedsuccessfully.
Keywords/Search Tags:Ship-in-a-bottle, HMSS, Mesoporousmolecularsieve, Cyclodextrin-zinc porphyrin
PDF Full Text Request
Related items