The surface of polypropylene (PP) membrane was modified by low temperature plasma with ammonia. The effect of exposure time was investigated by means of contact angle measurement. The results show that low temperature...The surface of polypropylene (PP) membrane was modified by low temperature plasma with ammonia. The effect of exposure time was investigated by means of contact angle measurement. The results show that low temperature ammonia plasma treatment can enhance its hydrophilicity. Chinese hamster ovary (CHO) cells attachment on the modified membrane was enhanced and the growth rate on the membrane was faster than unmodified one.展开更多
Tryptophan residues of IgGRF from rheumatoid arthritis patient were modified with N-Bromosuccinimide (NBS) and the product of modification was characterized by UV-spectrum、Fluorescence emission spectrum and CD-spectr...Tryptophan residues of IgGRF from rheumatoid arthritis patient were modified with N-Bromosuccinimide (NBS) and the product of modification was characterized by UV-spectrum、Fluorescence emission spectrum and CD-spectrum. The corresponding adsorption capacity of immobilized ssDNA immunoadsorbent for IgGRF was enhanced from 46% to 86%, This result indicates the tryptophan residue is essential for the interaction between ssDNA and IgGRF .and ionic-bonding plays an important role in adsorption.展开更多
Cholesterol modified dextran (CHD) having self-aggregation or self-assembly property was synthesized from cholesterol and 1,6-hexyldiisocyanate. The degree of substitution of cholesteryl moiety in dextran main line is...Cholesterol modified dextran (CHD) having self-aggregation or self-assembly property was synthesized from cholesterol and 1,6-hexyldiisocyanate. The degree of substitution of cholesteryl moiety in dextran main line is 3-5 cholesterols the 100 glucose units. We have prepared water solution of CHD using probe type sonifier and N-Phenyl-α-naphthylamine (PNA) as a fluorescent probe to study CHD self-aggregate process .For each solution of two samples, we found that the maximum emission of PNA in CHD solution was shifted to the lower wavelength and the intensity drastically increased above a critical CHD concentration. This change corresponds to the formation of micelle-like clusters self-aggregated by the cholesterol moiety once the CHD concentration exceeds 0.01 mg/ml.展开更多
Using polyvinyl alcohol (PVA) as raw material and vacuum pump oil as oil phase medium, PVA-based microcarriers were prepared by suspension method. The diameters of the beads were 100-180μm. LO2 cells were cultured on...Using polyvinyl alcohol (PVA) as raw material and vacuum pump oil as oil phase medium, PVA-based microcarriers were prepared by suspension method. The diameters of the beads were 100-180μm. LO2 cells were cultured on PVA-based microcarriers and cytodexIII microcarriers. Morphology, attachment and growth rate of LO2 cells were studied.展开更多
The interaction between amino-terminated, and ethylenediamine core poly(amidoamine) (PAMAM) den-drimers and herring sperm DNA was investigated by various spectroscopic methods including UV spectroscopy, fluores-cence ...The interaction between amino-terminated, and ethylenediamine core poly(amidoamine) (PAMAM) den-drimers and herring sperm DNA was investigated by various spectroscopic methods including UV spectroscopy, fluores-cence spectroscopy, microscopic FTIR- and circular dichro-ism (CD-) spectroscopy. Ethidium bromide (EB) is used as a nucleic acid probe for this study. Experimental results show that PAMAM dendrimers can form stable complexes with DNA and the dendrimers bind to DNA sufficiently strong which cannot be displaced by EB, and we also found that the formation of the complexes can cause the conformation change of the DNA secondary structure. According to the Scatchard analysis, the association constant of PAMAM to DNA is calculated to be 2.53 × 104 mol/L?1.展开更多
The interactions of amino-terminated, and ethylenediamine core poly(amidoamine) (PAMAM) den-drimers and their derivatives with bovine serum albumin (BSA) were investigated by fluorescence spectroscopy. Ex-perimental r...The interactions of amino-terminated, and ethylenediamine core poly(amidoamine) (PAMAM) den-drimers and their derivatives with bovine serum albumin (BSA) were investigated by fluorescence spectroscopy. Ex-perimental results showed that the fluorescence intensity of BSA decreased after the addition of different modified den-drimers, and the extent of the fluorescence quenching caused by various modified dendrimers strongly depends upon the different functional groups on their surfaces. We also inves-tigated the influence of pH and ionic strength on the interac-tion between various modified dendrimers and BSA. Circu-lar dichroism (CD) spectroscopic measurements showed that the content of α-helix structure of BSA decreased after the addition of different modified dendrimers, which indicated that dendrimers induced changes in the secondary structure of BSA.展开更多
基金The National Natural Science Foundation of China (No. 29776027)
文摘The surface of polypropylene (PP) membrane was modified by low temperature plasma with ammonia. The effect of exposure time was investigated by means of contact angle measurement. The results show that low temperature ammonia plasma treatment can enhance its hydrophilicity. Chinese hamster ovary (CHO) cells attachment on the modified membrane was enhanced and the growth rate on the membrane was faster than unmodified one.
基金National Basic Science and Development of China (G1999O64707)
文摘Tryptophan residues of IgGRF from rheumatoid arthritis patient were modified with N-Bromosuccinimide (NBS) and the product of modification was characterized by UV-spectrum、Fluorescence emission spectrum and CD-spectrum. The corresponding adsorption capacity of immobilized ssDNA immunoadsorbent for IgGRF was enhanced from 46% to 86%, This result indicates the tryptophan residue is essential for the interaction between ssDNA and IgGRF .and ionic-bonding plays an important role in adsorption.
文摘Cholesterol modified dextran (CHD) having self-aggregation or self-assembly property was synthesized from cholesterol and 1,6-hexyldiisocyanate. The degree of substitution of cholesteryl moiety in dextran main line is 3-5 cholesterols the 100 glucose units. We have prepared water solution of CHD using probe type sonifier and N-Phenyl-α-naphthylamine (PNA) as a fluorescent probe to study CHD self-aggregate process .For each solution of two samples, we found that the maximum emission of PNA in CHD solution was shifted to the lower wavelength and the intensity drastically increased above a critical CHD concentration. This change corresponds to the formation of micelle-like clusters self-aggregated by the cholesterol moiety once the CHD concentration exceeds 0.01 mg/ml.
基金The National Natural Science Foundation of China(No.29776027).
文摘Using polyvinyl alcohol (PVA) as raw material and vacuum pump oil as oil phase medium, PVA-based microcarriers were prepared by suspension method. The diameters of the beads were 100-180μm. LO2 cells were cultured on PVA-based microcarriers and cytodexIII microcarriers. Morphology, attachment and growth rate of LO2 cells were studied.
文摘The interaction between amino-terminated, and ethylenediamine core poly(amidoamine) (PAMAM) den-drimers and herring sperm DNA was investigated by various spectroscopic methods including UV spectroscopy, fluores-cence spectroscopy, microscopic FTIR- and circular dichro-ism (CD-) spectroscopy. Ethidium bromide (EB) is used as a nucleic acid probe for this study. Experimental results show that PAMAM dendrimers can form stable complexes with DNA and the dendrimers bind to DNA sufficiently strong which cannot be displaced by EB, and we also found that the formation of the complexes can cause the conformation change of the DNA secondary structure. According to the Scatchard analysis, the association constant of PAMAM to DNA is calculated to be 2.53 × 104 mol/L?1.
基金supported by the National Natural Science Foundation of China(Grant No.30370405).
文摘The interactions of amino-terminated, and ethylenediamine core poly(amidoamine) (PAMAM) den-drimers and their derivatives with bovine serum albumin (BSA) were investigated by fluorescence spectroscopy. Ex-perimental results showed that the fluorescence intensity of BSA decreased after the addition of different modified den-drimers, and the extent of the fluorescence quenching caused by various modified dendrimers strongly depends upon the different functional groups on their surfaces. We also inves-tigated the influence of pH and ionic strength on the interac-tion between various modified dendrimers and BSA. Circu-lar dichroism (CD) spectroscopic measurements showed that the content of α-helix structure of BSA decreased after the addition of different modified dendrimers, which indicated that dendrimers induced changes in the secondary structure of BSA.
