Table 4.

Liaison Question #3.

liaison	affiliation	data deemed necessary for nanomaterial comparison
Bill Zamboni	UNC	The need to be able to evaluate encapsulated/conjugated and released drug as part of formulation development and as part of in vivo PK studies. The need to evaluate biodistribution differences to tumor, tissues and the MPS. The need to evaluate the bi-directional interaction between nanoparticles and the MPS.
Christoph Steinbach, Clarissa Marquardt	DaNa database NanoRA	A very good question which is extremely hard to answer: What does “same material” mean, not only from the informational point of view but also from the other side, the definition of “same material”? Which set of parameters do you need? Even if you change the size or shape of a particle totally different behavior can be achieved. We have developed a set of criteria (see http://www.nanopartikel.info/files/methodik/DaNa-Literature-Criteria-Checklist_Methodology.pdf) which need to be fulfilled that we accept a certain publication as “knowledge” in the meaning described in the answer to the first question. Here we also describe the material characterization criteria. In fact we are absolutely aware that this does not make finally sure, that we are always talking of the “same” material, but for our purposes it’s enough. We think that a lot of further research is necessary to determine the right “same material” parameters. Furthermore the comparability in nano-sciences does not end with the “same” material as it is shown in certain round robin experiments [12–13]. Does it help when you assume to have the same material and the following experiments show different results because of other factors? I do not know if that leads to a better solution: Perhaps some kind mathematical probability that tells us x parameters (out of y parameters which can be determined with today’s characterization methods) of one substance are the same for another. The higher the number of same parameters the higher the probability the two substances are the “same”?
Marina (Nina) Vance	Nanotechnology Consumer Products Inventory	Within the CPI, it is very difficult to determine if a nanomaterial present in two or more products is, in fact, the same. We can group nanomaterials of the same composition together, but without a detailed description from the manufacturer, that would be impossible. In order to directly compare nanomaterials within consumer products, we would need, in the very least, the following: Composition, Shape, Size, Composition of coatings, Crystallinity
Christine Ogilvie Hendren	CEINT NIKC (Center for Environmental Implications of NanoTechnology NanoInformatics Knowledge Commons)	This depends on the level of granularity in the comparison. We believe that in order to support comparison and analysis in support of our research goals (elucidate mechanisms governing nanomaterial behavior and translate this into forecasts of risk), what is absolutely required are intrinsic characteristics of the nanomaterial, the surrounding system characteristics (e.g., be the system lab controlled, environmental media, biological systems), and system-dependent or "extrinsic" material characteristics. Only when all of these aspects, and their appropriate corresponding metadata describing preparation and testing protocols, are consistently reported can we know that direct comparison of two datasets is possible.
Julio Cesar Facelli, David Eugene Jones	NanoSifter (University of Utah)	The data (information) that is most necessary to directly compare nanomaterials and determine if they are the same material are the molecular descriptors and biochemical activity of the nanomaterials. The molecular descriptors (e.g., molecular weight, hydrodynamic diameter) and biochemical activity (e.g., cytotoxicity, cell viability, transfection efficiency) of the nanomaterials can be used by data mining and machine learning methods to compare materials and determine their similarity if the materials are discrete compounds. If the materials are not discrete compounds (i.e., polymers), properties such as molecular weight distribution and polydispersity will be the properties to assess for comparison of materials.