Optimization of intracellular macromolecule delivery by nanoparticle-mediated photoporation.

Nanoparticle-mediated photoporation is a novel delivery platform for intracellular molecule delivery. We studied the dependence of macromolecular delivery on molecular weight and sought to enhance delivery efficiency. DU145 prostate cancer cells were exposed to pulsed laser beam in the presence of carbon-black nanoparticles.

Serum Protects Cells and Increases Intracellular Delivery of Molecules by Nanoparticle-Mediated Photoporation.

Introduction: Intracellular delivery of molecules is central to applications in biotechnology, medicine, and basic research. Nanoparticle-mediated photoporation using carbon black nanoparticles exposed to pulsed, near-infrared laser irradiation offers a physical route to create transient cell membrane pores, enabling intracellular delivery. However, nanoparticle-mediated photoporation, like other physical intracellular delivery technologies, necessitates a trade-off between achieving efficient uptake of exogenous molecules and maintaining high cell viability.

Effect of laser fluence, nanoparticle concentration and total energy input per cell on photoporation of cells.

Intracellular delivery of molecules can be increased by laser-exposure of carbon black nanoparticles to cause photoporation of the cells. Here we sought to determine effects of multiple laser exposure parameters on intracellular uptake and cell viability with the goal of determining a single unifying parameter that predicts cellular bioeffects. DU145 human prostate cancer cells in suspension with nanoparticles were exposed to near-infrared nanosecond laser pulses over a range of experimental conditions.

Photoporation Using Carbon Nanotubes for Intracellular Delivery of Molecules and Its Relationship to Photoacoustic Pressure.

Exposure of carbon-black (CB) nanoparticles to near-infrared nanosecond-pulsed laser energy can cause efficient intracellular delivery of molecules by photoporation. Here, cellular bioeffects of multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs) are compared to those of CB nanoparticles. In DU145 prostate-cancer cells, photoporation using CB nanoparticles transitions from (i) cells with molecular uptake to (ii) nonviable cells to (iii) fragmented cells with increasing laser fluence, as seen previously.

Design and fabrication of distributed Bragg reflector multilayers for dynamic pressure sensing.

A novel 2D-surface shock pressure sensor is designed and tested based on 1D-Photonic Crystal, i.e., Distributed Bragg Reflector Multilayer (DBR/ML) structures.

Role of cytoskeletal mechanics and cell membrane fluidity in the intracellular delivery of molecules mediated by laser-activated carbon nanoparticles.

Exposure of cells and nanoparticles to near-infrared nanosecond pulsed laser light can lead to efficient intracellular delivery of molecules while maintaining high cell viability by a photoacoustic phenomenon known as transient nanoparticle energy transduction (TNET). Here, we examined the influence of cytoskeletal mechanics and plasma membrane fluidity on intracellular uptake of molecules and loss of cell viability due to TNET. We found that destabilization of actin filaments using latrunculin A led to greater uptake of molecules and less viability loss caused by TNET.

Energy Transfer Mechanisms during Molecular Delivery to Cells by Laser-Activated Carbon Nanoparticles.

Previous studies have shown that exposure of carbon black nanoparticles to nanosecond pulsed near-infrared laser causes intracellular delivery of molecules through hypothesized transient breaks in the cell membrane. The goal of this study is to determine the underlying mechanisms of sequential energy transfer from laser light to nanoparticle to fluid medium to cell. We found that laser pulses on a timescale of 10 ns rapidly heat carbon nanoparticles to temperatures on the order of 1200 K.

Asymmetrical optical microcavity structures for dynamic pressure sensing: design, fabrication, validation.

Optical microcavity (OMC) structures have spectral properties that are directly related to their physical dimensions and material refractive indices. Their intrinsically fast optical response to mechanically-induced changes in these parameters makes OMCs uniquely suited for dynamic sensing when paired with a suitably fast streak camera and spectrograph. Various designs and processes of fabrication for asymmetrical OMC (AOMC) structures were investigated to optimize and assess their feasibility for dynamic sensing.

Poloxamer surfactant preserves cell viability during photoacoustic delivery of molecules into cells.

Efficient intracellular delivery of molecules is needed to modulate cellular behavior for laboratory and medical applications, but is often limited by trade-offs between achieving high intracellular delivery and maintaining high cell viability. Here, we studied photoacoustic delivery of molecules into cells by exposing DU145 human prostate carcinoma cells to nanosecond laser pulses in the presence of carbon black nanoparticles. Under strong laser exposure conditions, less than 30% of cells were viable and exhibited uptake.