Nanomedicine(s) under the Microscope

Abstract

Depending on the context, nanotechnologies developed as nanomedicines (nanosized therapeutics and imaging agents) are presented as either a remarkable technological revolution already capable of delivering new diagnostics, treatments for unmanageable diseases, and opportunities for tissue repair or highly dangerous nanoparticles, nanorobots, or nanoelectronic devices that will wreak havoc in the body. The truth lies firmly between these two extremes. Rational design of "nanomedicines" began almost half a century ago, and >40 products have completed the complex journey from lab to routine clinical use. Here we critically review both nanomedicines in clinical use and emerging nanosized drugs, drug delivery systems, imaging agents, and theranostics with unique properties that promise much for the future. Key factors relevant to the design of practical nanomedicines and the regulatory mechanisms designed to ensure safe and timely realization of healthcare benefits are discussed.

Spatial Analysis of Metal–PLGA Hybrid Microstructures Using 3D SERS Imaging

“…Bicompartmental PLGA Particles: Bicompartmental PLGA particles were synthesized using 50-75 kDA PLGA (#430471 Aldrich) and a solvent ratio of 97:3 for CHCl 3 Bicompartmental Cylinders: Bicompartmental fibers were deposited in an aligned orientation on a tissue cryomold, and then embedded in a Tissue-Plus matrix. They were stored at −4 °C for 24 h, after being cut using a Leica 3050S cryostat cryosectioning instrument.…”

“…[1,2] The development of new microscopic and spectroscopic techniques combined with the preparation of nanomaterials with a high degree of control is crucial Imaging to the development of new drug carrier systems and therapeutic methods. [3] One example is given by surface-enhanced Raman scattering (SERS), a ultrasensitive imaging tool, which, in combination with engineered particle systems, has already found a variety of applications. [4,5] The ability to tune the excitation wavelength into the near infrared (NIR) range, the so-called biological transparency window (650-950 nm), leads to improved light penetration in living tissue, while the low Raman cross section of water and the potential for multiplexed measurements over long periods of time, render this technique ideal for nanomedicine applications.…”

Evaluating Plasma Pharmacokinetics of Intravenous Iron Formulations: Judging Books by Their Covers?

“…Ferumoxytol is a superparamagnetic iron oxide nanoparticle (SPION), which was originally developed for use in magnetic resonance imaging (MRI). Biodistribution data for SPIONs demonstrate that different carbohydrate shell structures determine the relative uptake by endothelial and lymphatic cells, as well as by the reticuloendothelial system [6]. Thus, analysis of only short-term plasma PK provides limited information on the ultimate disposition and fate of these agents.…”

“…These agents have not been well studied with regard to comparative biodistribution, metabolic fate, and potential extracellular and intracellular deposition profiles, and further evaluation of these agents is urgently needed. Analysing short-term plasma data to infer IV iron-carbohydrate PK profiles has been typically acceptable for IV iron registry trials; however, on the basis of the SPION data in the MRI literature, these agents exhibit complicated PK and pharmacodynamic (PD) profiles, which can differ vastly between agents because of carbohydrate shell heterogeneity [6]. Thus, although shortterm plasma PK profiles among groups of healthy and diseased subjects appear to exhibit little variability, there is a paucity of data studying repeated-dose administration and compartmental PK of IV iron formulations.…”

Nanomaterials for (Nano)medicine

“…They are present in many nanomedicines that made it to the clinic, and most likely, they will appear to some extent also in the nanomedicines of the future. 1 However, if we look a bit further and stretch our eyes toward the horizon, we will see how the landscape changes as we encounter the less-explored nanomaterials. Nanoparticles (NPs), quantum dots (QDs), and carbon nanotubes (CNTs), in one form or another, are all there.…”