Bifunctional Au-templated RNA nanoparticles enable direct cell uptake detection and GRP75 knockdown in prostate cancer.
Sunil S ShahChristopher N CultraraJorge A RamosUri SamuniJenny ZilberbergDavid SabatinoPublished in: Journal of materials chemistry. B (2021)
Nucleic acids templated on gold (Au) surfaces have led to a wide range of functional materials ranging from microarrays, sensors and probes in addition to drug delivery and treatment. In this application, we describe a simple and novel method for templating amino-functionalized RNA onto Au surfaces and their self-assembly into small, discrete nanoparticles. In our method, sample hybridization with a complementary RNA strand with and without a fatty acid (palmitamide) appendage produced functionalized double-stranded RNA on the Au surface. The resulting Au-functionalized RNA particles were found to be stable under reducing conditions according to UV-Vis spectroscopy. Sample characterization by DLS and TEM confirmed self-assembly into primarily small (∼10-40 nm) spherical shaped nanoparticles expected to be amenable to cell biology. However, fluorescence emission (λexc: 350 nm, λem: 650 nm) revealed radiative properties which limited cell uptake detection. Introduction of FITC within the Au-functionalized RNA particles produced a bifunctional probe, in which FITC fluorescence emission (λexc: 494 nm, λem: 522 nm) facilitated cell uptake detection, in a time-dependent manner. The dual encapsulation-release profiles of the FITC-labeled Au-functionalized RNA particles were validated by time-dependent UV-Vis spectroscopy and spectrofluorimetry. These experiments respectively indicated an increase in FITC absorption (λabs: 494 nm) and fluorescence emission (λem: 522 nm) with increased sample incubation times, under physiological conditions. The release of Au-functionalized siRNA particles in prostate cancer (PC-3) cells resulted in concomitant knockdown of GRP75, which led to detectable levels of cell death in the absence of a transfection vector. Thus, the formulation of stable, small and discrete Au-functionalized RNA nanoparticles may prove to be valuable bifunctional probes in the theranostic study of cancer cells.
Keyphrases
- sensitive detection
- quantum dots
- prostate cancer
- nucleic acid
- photodynamic therapy
- single molecule
- reduced graphene oxide
- single cell
- drug delivery
- cell death
- cell therapy
- loop mediated isothermal amplification
- molecularly imprinted
- fatty acid
- light emitting
- small molecule
- signaling pathway
- high resolution
- energy transfer
- stem cells
- staphylococcus aureus
- mesenchymal stem cells
- living cells
- escherichia coli
- bone marrow
- endoplasmic reticulum stress
- computed tomography
- real time pcr
- solid state
- low cost
- smoking cessation
- pet imaging