Nanoparticles (NPs) have gained increasing interest in recent years due to their potential use as drug carrier, imaging, and diagnostic agents in pharmaceutical and biomedical applications. While many cells in vivo experience mechanical forces, little is known about the correlation of the mechanical stimulation and the internalization of NPs into cells. This paper investigates the effects of ap...

of the 3H-label in their experiments is associated with the cells is difficult to interpret. Although some of the experiments by Hammes et al. are consistent with their “bound steroid” hypothesis (see, for example, Figure 2A), others are not (for example, see Figures 2B and 2C). At a concentration of 1 nM DHT plus 1 nM SHBG, 50% of the steroid exists in the free form. One nanomole of DHTSHBG an...

DNA-based nanostructures have received great attention as molecular vehicles for cellular delivery of biomolecules and cancer drugs. Here, we report on the cellular uptake of tubule-like DNA tile-assembled nanostructures 27 nm in length and 8 nm in diameter that carry siRNA molecules, folic acid and fluorescent dyes. In our observations, the DNA structures are delivered to the endosome and do n...

THE PROCESS of cellular uptake and metabolism of cyclosporine (CsA) is poorly understood. Earlier studies in this laboratory indicated that transport of CsA in blood occurs in association with plasma lipoproteins, with low density lipoprotein (LDL) and high density lipoprotein (HOL) carrying about 32% each of the total CsA in blood. This observation suggests the possibility that the cellular up...

Due to the superior photoemission and photostability characteristics, quantum dots (QD) are novel tools in biological and medical applications. However, the toxicity and mechanism of QD uptake are poorly understood. QD nanoparticles with an emission wavelength of 655 nm are ellipsoid in shape and consist of a cadmium/selenide core with a zinc sulfide shell. We have shown that QD with a carboxyl...

Gold nanorods coated with cetyltrimethylammonium bromide (CTAB), a cationic micellar surfactant used in nanorod synthesis, were rapidly and irreversibly internalized by KB cells via a nonspecific uptake mechanism. Internalized nanorods near the cell surface were monitored by two-photon luminescence (TPL) microscopy and observed to migrate toward the nucleus with a quadratic rate of diffusion. T...

circulation and represent an important, readily available energy source for certain organs like liver and heart. Controversy exists over how they are translocated across the plasma membrane [ 13. Since albumin is not taken up into the cells, only the dissociated unbound fatty acids are available for uptake. For evaluation of whether this uptake occurs by simple diffusion or facilitated transpor...

Quantum dots (QDs) are often cell-impermeable and require transporters to facilitate crossing over cell membranes. Here we present a simple and versatile method that utilizes enzymes, matrix metalloprotease 2 (MMP-2) and MMP-7, to modulate the cellular uptake of QDs. QD-peptide conjugates could be efficiently taken up into cells after the MMP treatment. This enzyme-modulated cellular uptake of ...