Free-base and nickel porphyrin-diaminopurine conjugates were formed by hydrogen-bond directed assembly on single-stranded oligothymidine templates of different lengths into helical multiporphyrin nanoassemblies with highly modular structural and chiroptical properties. Large red-shifts of the Soret band in the UV/Vis spectroscopy confirmed strong electronic coupling among assembled porphyrin-diaminopurine units. Slow annealing rates yielded preferentially right-handed nanostructures, whereas fast annealing yielded left-handed nanostructures. Time-dependent DFT simulations of UV/Vis and CD spectra for model porphyrin clusters templated on the canonical B-DNA and its enantiomeric form, were employed to confirm the origin of observed chiroptical properties and to assign the helicity of porphyrin nanoassemblies. Molar CD and CD anisotropy g factors of dialyzed templated porphyrin nanoassemblies showed very high chiroptical anisotropy. The DNA-templated porphyrin nanoassemblies displayed high thermal and pH stability. The structure and handedness of all assemblies was preserved at temperatures up to +85 °C and pH between 3 and 12. High-resolution transition electron microscopy confirmed formation of DNA-templated nickel(II) porphyrin nanoassemblies and their self-assembly into helical fibrils with micrometer lengths.
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http://dx.doi.org/10.1002/chem.201304153 | DOI Listing |
J Nanobiotechnology
December 2024
Key Laboratory of Emergency and Trauma of Ministry of Education, Engineering Research Center for Hainan Biological Sample Resources of Major Diseases, the Hainan Branch of National Clinical Research Center for Cancer, the First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China.
Limited drug accumulation and an immunosuppressive microenvironment are the major bottlenecks in the treatment of glioblastoma multiforme (GBM). Herein, we report a copper-coordination driven brain-targeting nanoassembly (TCe6@Cu/TP5 NPs) for site-specific delivery of therapeutic agents and efficient immunotherapy by activating the cGAS-STING pathway and downregulating the expression of PD-L1. To achieve this, the mitochondria-targeting triphenylphosphorus (TPP) was linked to photosensitizer Chlorin e6 (Ce6) to form TPP-Ce6 (TCe6), which was then self-assembled with copper ions and thymopentin (TP5) to obtain TCe6@Cu/TP5 NPs.
View Article and Find Full Text PDFAdv Mater
December 2024
Department of General Surgery, Zhujiang Hospital, Cancer Research Institute, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China.
Most patients with cancer are first diagnosed at an advanced disease stage, when tumors are already large and/or metastases are present. This circumstance has a negative impact on the prognosis and therapeutic effect of anticancer drugs. In this study, it is demonstrated that photosensitizer chlorin e6 and the photochemotherapy drug mitoxantrone self-assemble into relatively stable nanoassemblies (CM NAs) through hydrogen-bonding effect, π-π stacking, and hydrophobic interactions.
View Article and Find Full Text PDFMikrochim Acta
October 2024
State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
A covalent assembly strategy was developed to construct a gold nanocluster-based nano-assembly (AuNCNA) in a controllable manner, using Au nanocluster as node and 5,10,15,20-tetra(4-alkynylphenyl)porphine (TEPP) as ligand. Subsequently, the tripeptide arginine glycine aspartic acid (RGD) peptide is further modified via clicking reaction to build a multi-functional nanoplatform (AuNCNA@RGD) that can integrate the targeted fluorescence imaging and efficient photodynamic therapy (PDT). The strong interregulation of Au nanocluster and TEPP results in AuNCNA@RGD exhibiting three distinct advantages: (i) TEPP plays an important role in stabilizing the Au nanocluster and keeping the active site fixed within the framework, thereby enhancing stability of Au nanocluster; (ii) Au nanocluster possess adjustable energy level, which can accelerate the transfer of photogenerated charge and prevent the recombination of electrons and holes, thus improving the photosensitivity of TEPP for PDT; (iii) AuNCNA exhibits bright fluorescence emission that facilitates RGD-assisted targeted tumor imaging.
View Article and Find Full Text PDFChem Asian J
October 2024
School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Angew Chem Int Ed Engl
October 2024
Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Shanghai Key Laboratory of Functional Materials Chemistry, Feringa Nobel Prize Scientist Joint Research Center, Institute of Fine Chemicals, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Photodynamic therapy (PDT) is a clinically approved therapeutic modality that has shown great potential for cancer treatment. However, there exist two major problems hindering PDT applications: the nonspecific phototoxicity requiring patients to stay in dark post-PDT, and the limited photodynamic efficiency. Herein, we report a photo-triggered porphyrin polyelectrolyte nanoassembling (photo-triggered PPN) strategy, in which porphyrin photosensitizer and photoswitchable energy accepter are assembled into polyelectrolyte micelles by a combined force of charge interaction and metal-ligand coordination.
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