The characteristics of heparinized multiwalled carbon nanotubes (MWNTs) were investigated in terms of the activated partial thromboplastin time (APTT) to verify the heparin activity, a carbazole assay was done to measure the content of the immobilized heparin, and the octanol-water partition coefficient was assessed to determine the lipophilicity. Two heparin-immobilized MWNTs were prepared to evaluate their differences. The first preparation method involved polymer-coated MWNTs with heparin indirectly center-point-attached. In the second approach, heparin was directly end-point-attached through its reducing end onto acid-treated MWNTs. The blood compatibility of MWNTs to which heparin was end-point-attached through its reducing end was greatly enhanced compared to that of the MWNTs onto which heparin was center-point-attached. The APTT and carbazole assay results demonstrated that heparinized MWNTs prepared through end-point attachment result in prolonged plasma-based anticoagulant activity. The blood compatibility of MWNTs heparinized by end-point attachment was not decreased up to the fourth pasteurization. Heparinized MWNTs were also studied using octanol-water partition, which should be useful for exploring heparinized MWNTs as drug carriers including delivery systems. The results of octanol/water partition on the design of heparinized MWNTs prepared by end-point attachment with a specific binding can facilitate the design of drug delivery carriers with high blood compatibility.
Bibliographical noteFunding Information:
This work was supported by a National Research Foundation (NRF) grant funded by the Korea Government (MEST) through the Active Polymer Center for Pattern Integration (R11-2007-050-00000-0). This research was supported by Future-based Technology Development Program (Nano Fields) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0019175). Further support came from the Pioneer Research Center Program (2010-0019308), the Original Technology Research Program for Brain Science (2011-0030168), and the Converging Research Center Program (2009-0082832) through the NRF funded by the Ministry of Education, Science and Technology, from the Seoul Research and Business Development Program (10816), and from the Research Fund 2010 of The Catholic University of Korea .
All Science Journal Classification (ASJC) codes
- Applied Microbiology and Biotechnology