pH-Responsive Dimeric Zinc(II) Phthalocyanine in Mesoporous Silica Nanoparticles as an Activatable Nanophotosensitizing System for Photodynamic Therapy

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal

19 Scopus Citations
View graph of relations

Author(s)

  • Roy C.H. Wong
  • Sun Y.S. Chow
  • Shirui Zhao
  • Wing-Ping Fong
  • Dennis K.P. Ng

Related Research Unit(s)

Detail(s)

Original languageEnglish
Pages (from-to)23487-23496
Journal / PublicationACS Applied Materials and Interfaces
Volume9
Issue number28
Online published29 Jun 2017
Publication statusPublished - 19 Jul 2017

Abstract

An acid-cleavable acetal-linked zinc(II) phthalocyanine dimer with an azido terminal group (cPc) was prepared and conjugated to alkyne-modified mesoporous silica nanoparticles via copper(I)-catalyzed alkyne−azide cycloaddition reaction. For comparison, an amine-linked analogue (nPc) was also prepared as a non-acid-cleavable counterpart. These dimeric phthalocyanines were significantly selfquenched due to the close proximity of the phthalocyanine
units inside the mesopores, resulting in much weaker fluorescence emission and singlet oxygen generation, both in N,N-dimethylformamide and in phosphate-buffered saline (PBS), compared with the free molecular counterparts. Under acidic conditions in PBS, the cPc-encapsulated nanosystem was activated in terms of fluorescence emission and singlet oxygen production. After internalization into human colon adenocarcinoma HT29 cells, it exhibited much higher intracellular fluorescence and photocytotoxicity compared to the nanosystem entrapped with nPc. The activation of this nanosystem was also demonstrated in tumor-bearing nude mice. The intratumoral fluorescence intensity increased gradually over 24 h, while for the nPc counterpart the fluorescence remained very weak. The results suggest that this nanosystem serves as a promising activatable anophotosensitizing agent for photodynamic therapy.

Research Area(s)

  • activatable, mesoporous silica nanoparticle, photodynamic therapy, photosensitizer, phthalocyanine, self-quenching

Citation Format(s)

pH-Responsive Dimeric Zinc(II) Phthalocyanine in Mesoporous Silica Nanoparticles as an Activatable Nanophotosensitizing System for Photodynamic Therapy. / Wong, Roy C.H.; Chow, Sun Y.S.; Zhao, Shirui; Fong, Wing-Ping; Ng, Dennis K.P.; Lo, Pui-Chi.

In: ACS Applied Materials and Interfaces, Vol. 9, No. 28, 19.07.2017, p. 23487-23496.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal