The unique photophysical properties of noble metal nanoparticles contribute to their potential as photoactivated drug delivery vectors. Here we demonstrate the synthesis and characterization of 60-80 nm silver nanoparticles (SNPs) decorated with thiol-terminated photolabile DNA oligonucleotides. In vitro assays and fluorescent confocal microscopy of treated cell cultures show efficient UV-wavelength photoactivation of surface-tethered caged ISIS2302 antisense oligonucleotides possessing internal photocleavable linkers.
View Article and Find Full Text PDFGold nanoparticles with tunable absorption and scattering properties have been developed as contrast agents for various optical imaging techniques. As a hybrid modality that combines the merits of both optical and ultrasonic imaging, photoacoustic (PA) imaging also benefits from the use of these nanoparticles to greatly enhance the contrast for visualization of structures and biomarkers in biological tissues. Gold nanocages characterized by hollow interiors, ultrathin and porous walls are of particular interest for in vivo PA imaging because of their compact sizes, bio-inertness and well-defined surface chemistry, as well as their strong and highly wavelength-tunable optical absorption in the near-infrared (NIR) optical window of soft tissues.
View Article and Find Full Text PDFGold nanostructures have garnered considerable attention in recent years for their potential to facilitate both the diagnosis and treatment of cancer through their advantageous chemical and physical properties. The key feature of Au nanostructures for enabling this diverse array of biomedical applications is their attractive optical properties, specifically the scattering and absorption of light at resonant wavelengths due to the excitation of plasmon oscillations. This phenomenon is commonly known as localized surface plasmon resonance (LSPR) and is the source of the ruby red color of conventional Au colloids.
View Article and Find Full Text PDFIn this study, we demonstrate that the presence of serum in different media plays an important role in inducing transient and reversible adhesion in Jurkat suspension cells. Attachment of Jurkat cells in two distinct media formulations (serum-fortified and serum-free) to untreated polystyrene (PS), plasma-treated PS, and fibronectin-coated PS was compared. Additional analysis characterized the occurrence of this transient cell adhesion, including attachment rate, reversibility of attachment, and viability and preservation of phenotype in cells during and after attachment.
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