Site-Selective Nucleation and Size Control of Gold Nanoparticle Photothermal Antennae on the Pore Structures of a Virus

Abstract

In this Article, we show that the surface of the bacteriophage Qβ is equipped with natural ligands for the synthesis of small gold nanoparticles (AuNPs). By exploiting disulfides in the protein secondary structure and the geometry formed from the capsid quaternary structure, we find that we can produce regularly arrayed patterns of ∼6 nm AuNPs across the surface of the virus-like particle. Experimental and computational analyses provide insight into the formation and stability of this composite. We further show that the entrapped genetic material can hold upward of 500 molecules of the anticancer drug Doxorubicin without leaking and without interfering with the synthesis of the AuNPs. This direct nucleation of nanoparticles on the capsid allows for exceptional conduction of photothermal energy upon nanosecond laser irradiation. As a proof of principle, we demonstrate that this energy is capable of rapidly releasing the drug from the capsid without heating the bulk solution, allowing for highly targeted cell killing in vitro.

Viral nanoparticles for drug delivery, imaging, immunotherapy, and theranostic applications

“…Compared with conventional therapeutic modalities, PTT exhibits unique advantages in cancer therapy such as high specificity, minimal invasiveness, and precise spatial-temporal selectivity [212,213]. Qβ-based VLPs were engineered for PTT through the attachment of sub 7-nm sized gold nanoparticles on their surface; the inner cavity was loaded with upwards of 500 DOX molecules [214]. Upon 6-nanosecond laser irradiation, DOX was rapidly released from the capsid without heating the bulk solution, allowing for highly targeted cell killing of RAW264.7 macrophage and A549 lung cancer cells in vitro.…”

Polydopamine-decorated tobacco mosaic virus for photoacoustic/magnetic resonance bimodal imaging and photothermal cancer therapy

“…Biocompatibility and photothermal conversion efficiency are the most challenging aspects for the development of effective PTT agents. 8,9 Plasmonic metal nanoparticles such as Ag 26 , Au [27][28][29] and Pt 30 , carbon nanomaterials such as graphene 31 and carbon nanotubes 32 , and minerals such as iron oxide 33 and copper selenide 34,35 have been widely used as PTT agents for preclinical research, the biocompatibility of such modalities is low. 12 In contrast, polydopamine (PDA) is a melanin-like mimic of mussel adhesion proteins, which shows excellent photothermal stability, biocompatibility and biodegradability.…”

Metal–Organic Framework Disintegrants: Enzyme Preparation Platforms with Boosted Activity

“…Immobilization of enzymes using solid supports is ap opular strategy to stabilize enzymes. [14][15][16] However,t hese heterogeneous biocatalytic systems often suffer from the decrease of catalytic efficiency or low enzyme availability due to the diffusion issue caused by the supports.I nt he past decade,metal-organic frameworks (MOFs) have emerged as anew class of enzyme supports (enzyme@MOFs,@= encapsulating) which can effectively incorporate and stabilize enzymes, [17][18][19][20] owing to their adaptable structures,h igh porosity,t unable pore size,a nd customizable functionality. [21][22][23][24] Interestingly,M OFs can be degradable under mild conditions.…”