Innovations in nanotechnology are generating a broad array of new materials that have novel and useful properties. Due to the increased prevalence of nanomaterials in consumer products, there is a growing interest in understanding the relationship between the physical and chemical properties of nanomaterials and their potential risk to the environment and human health. In order to fully understand how the nanomaterials interact with biological systems and the environment, researchers must use materials with precisely defined physical and chemical characteristics.

Handbook for nanotoxicology researchers using nanoComposix Materials

Nanomaterials for Toxicology

NanoComposix provides precisely sized, unagglomerated, highly purified, and extensively characterized nanoparticles to researchers. The company was recently selected by the Organization of Economic Cooperation and Development (OECD) to provide 3 of their 5 silver nanoparticle standards. All nanomaterials fabricated at nanoComposix are provided with a comprehensive specification sheet describing the physical and chemical characteristics of each material, allowing researchers to test the toxicological response of size, shape, material, and surface chemistry against the appropriate controls.

Nanoparticle Selection

When selecting a nanoparticle it's important to take into account the potential effects that nanomaterial size, shape, and surface may have.

  • Size and Aggregation State: Size is a critical parameter which determines the surface area per unit mass and melting point, and can strongly effect the material uptake and biodistribution. Aggregation can significantly increase the effective nanoparticle size. For more information on selecting the appropriately sized material for your research, please see our Knowledge Base article titled Understanding the Effects of Size.
  • Shape: Shape can impact toxicological effects by effecting cell uptake or decreasing the rate of material clearance from the system. In some cases, shaped particles have well defined crystal structures which can preferentially interact with specific proteins in solution. For more information on selecting the appropriate shape for your research, please see our Knowledge Base article titled Understanding the Effects of Shape.
  • Surface: The stability, uptake, and protein corona of nanoparticles in toxicity assays are dominated by surface effects. Different surface molecules determine if the particles are positively or negatively charged, hydrophobic or hydrophillic, lipophobic or lipophillic, and the extent to which they will interact with other molecules or trigger an immune response. For more information on selecting the appropriate surface, please see our Knowledge Base article titled Understanding the Effects of Surface.

Available Nanomaterials

At nanoComposix, we fabricate precisely sized, extensively purified, highly characterized nanomaterials with a variety of sizes, shapes, and surfaces. One of our most popular lines for nanotoxicology is BioPure, which features particles that are guaranteed to be sterile and endotoxin-free.

When testing a nanomaterial for toxicity it is important to differentiate between the toxic effects of the nanoparticles and the toxic effects of residual reactants. Controls for residual reactants can be run by analyzing the particle supernatent, which will test for effects due to residual reactants.  For more information regarding experimental controls and residual reactants, please see our Knowledge Base articles on positive controls and residual reactants.

Nanoparticle Transformation

Nanoparticles are dynamic, multi-component composites that undergo rapid changes when exposed to environmentally or biologically relevant media. Determining how aggregation, surface binding, and dissolution of nanoparticles affect dose, transport, and toxicity is a major challenge for toxicology researchers. By starting with unagglomerated nanoparticles with a known surface chemistry, experiments that probe transformation experiments can be designed and interpreted. For more information on the dynamic nature of nanoparticles visit our Nanotoxicology Knowledge Base.

Experimental Integration

Due to the complexity of nanoparticle interactions with target systems, it is essential that researchers understand how the physical and chemical characteristics of nanoparticles change with time and the impact of these changes on experimental protocols. For example, the response of a system to a specific mass of nanoparticles can be wildy different depending on the order and timing of the addition, the agglomeration state, and the storage conditions of the nanoparticles. Predicting or measuring how the physical and chemical properties of the nanomaterials change during your experiment will allow for a more complete and accurate interpretation of biological endpoints.

Characterization

Characterization of nanoparticles before, during, and after introduction into the test system provides critical information that can be used to understand the interaction of the system with the nanoparticles. However, once nanoparticles are exposed to a hetergeneous and complex environmental or biological system, it is difficult to determine the state of the nanoparticles. At nanoComposix we utilize a wide variety of characterization techniques to monitor the state of nanoparticles over time and provide both data and methods useful for nanotoxicology researchers.

Results & Publications

Over 100 government agencies, university researchers, and industrial toxicologists have performed experiments using nanoComposix's nanoparticle formulations and a rapidly growing volume of publications are available. Published protocols associated with specific nanoparticle sizes, shapes, and surfaces make a valuable resource for researchers designing new experiments. With starting nanomaterials and associated protocols becoming better defined, consistent and correlated trends across different biological systems and in different research laboratories are being observed. For more information see a list of recent publications using nanoComposix materials.