A microporous covalent triazine polymer (CTP) network with a high surface area was synthesized via the Friedel-Crafts reaction for anticancer drug delivery and controlled release. The CTP is transformed to the nanoscale region by intense ultasonication followed by filtration to yield nanoscale CTP (NCTP) with excellent dispersibility in physiological solution while maintaining its chemical structure and the porosity of the material. An anti-cancer drug, doxorubicin (DOX), is loaded onto the NCTP through simple physisorption by hydrophobic and π–π interactions, and its release can be controlled at acidic and neutral pH. The NCTP did not show practical toxicity to cancer and normal cells, but the NCTP-DOX complex showed high efficacy at killing both types of cells in-vitro. The prolonged drug release (over 50h) from the NCTP-DOX at neutral and acidic pH values was demonstrated. The in-vitro cell imaging results indicate that NCTP has good potential for bio-imaging. The cellular senescence and potency of NCTP was confirmed by the expression of senescence associated marker proteins p53 and p21. These results suggest that NCTP can be used as a new platform for imaging and drug delivery, which may find potential applications in diagnosis and therapy.

1. Porous Covalent Triazine Polymer as a Potential Nanocargo for Cancer Therapy and
Imaging
Arunkumar Rengaraj,aѱ Pillaiyar Puthiaraj,bѱ Yuvaraj Haldorai,c Nam Su Heo,a Seung-Kyu Hwang,a Soonjo Kwo
n,d Wha-Seung Ahn,b* and Yun Suk Huha*
aDepartment of Biological Engineering, Biohybrid Systems Research Center (BSRC), Inha University, Incheon, 402-751,
Republic of Korea.
bDepartment of Chemistry and Chemical Engineering, Inha University, Incheon 402-751, Republic of Korea.
cDepartment of Energy and Materials Engineering, Dongguk University-Seoul, Seoul ,100-715, Republic of Korea.
dDepartment of Biological Engineering, Integrated Tissue Culture Laboratory, Inha University, Incheon, 402-751, Repub
lic of Korea.
Fax: +82-32-872-4046; Email:yunsuk.huh@inha.ac.kr
Ѱ–These two authors contributed equally

2. Abstract
A microporous covalent triazine polymer (CTP) network with a high surface area was synthesized via the Friedel-Crafts reaction f
or anticancer drug delivery and controlled release. The CTP is transformed to the nanoscale region by intense ultasonication follow
ed by filtration to yield nanoscale CTP (NCTP) with excellent dispersibility in physiological solution while maintaining its chemic
al structure and the porosity of the material. An anti-cancer drug, doxorubicin (DOX), is loaded onto the NCTP through simple ph
ysisorption by hydrophobic and π–π interactions, and its release can be controlled at acidic and neutral pH. The NCTP did not sho
w practical toxicity to cancer and normal cells, but the NCTP-DOX complex showed high efficacy at killing both types of cells in-
vitro. The prolonged drug release (over 50h) from the NCTP-DOX at neutral and acidic pH values was demonstrated. The in-vitro
cell imaging results indicate that NCTP has good potential for bio-imaging. The cellular senescence and potency of NCTP was con
firmed by the expression of senescence associated marker proteins p53 and p21. These results suggest that NCTP can be used as a
new platform for imaging and drug delivery, which may find potential applications in diagnosis and therapy.
Keywords: Covalent triazine polymer, Porous material, Fluorescence, Biocompatible, Drug delivery

3. Scheme 1 Strategy employed to synthesize NCTP-DOX.

4. Figure 1 (a) FTIR, (b) BET, (c) zeta potential, and (d) PL
analysis of NCTP.

5. Figure 2 SEM and TEM analysis of CTP (a, d) before sonication, (b, e) after sonication, and (c, f) after filtration.

6. Figure 3 Cytotoxic study of the NCTP (a) COS-7 and (b) HeLa
cells.

7. Figure 4 (a) Loading efficiency of DOX, (b) pH induced
controlled drug release, and (c) mechanism for pH induced drug
release.

8. Figure 5 (a) Optical microscopic images, (b) confocal fluorescence microscopy images, and (c) overlay of HeLa cells before
(i) and after (ii, iii) being incubated for 24 h with NCTP and NCTP-DOX.

9. Figure 6 Relative cell viability of (a) COS-7 and (b) HeLa cells treated with free DOX and NCTP-DOX at various
concentrations, and (c) Bio-TEM images of (i) control and (ii) NCTP-DOX treated HeLa cells after 6 h.

10. Figure 7 SA β-galactosidase assay for NCTP-DOX (a) before staining, (b) after staining and protein expression of (c)
DOX and (d) NCTP-DOX on HeLa cells.

11. In summary, we successfully synthesized NCTP and used it as both a potential
photosensitizer and pH-responsive nanocarrier for cancer therapy and imaging. NCTP with
pH-dependent drug releasing properties were suitable for drug delivery over cancer cells.
The NCTP-DOX exhibited a higher cytotoxic effect on cancer cells than free DOX and
induced strong senescence at lower concentration. Of particular significance, the NCTP–
DOX complex features a DOX-loading capacity of 200 mg/g due to its high specific surface
area, π-π stacking and hydrophobic interaction. Our results indicate the potential for use of
NCTP as a low-toxic and biocompatible 2D nanomaterial for cancer diagnosis and therapy.