By Nanotechnology Characterization Laboratory (NCL)
Physical attributes are key factors contributing to a nanomaterial's in vivo behavior and tolerability. Using state-of-the-art instrumentation, nanoparticles are subjected to a thorough assessment of their physical and chemical properties, including the particle's size, size distribution, molecular weight, morphology, surface characteristics, composition, and purity. In addition to evaluating direct traits of the particle, aspects such as stability, lot-to-lot reproducibility, as well as assessment of the starting materials are also critical components of the characterization process. Many physicochemical characterization assays are individually tailored for each nanoparticle; therefore, this does not represent an exhaustive list of assays available for the physicochemical characterization of the various nanoparticle platforms. NCL will work alongside investigators to understand the intricacies of their formulation and develop a testing plan that fills any critical gaps in their knowledge and understanding of the formulation. Among the most common nanotechnology platforms used in drug delivery are liposomes, colloidal metal nanoparticles, and polymeric/polymeric-prodrug nanoparticles. To assist developers working with these platforms, the NCL has created an overview of the most critical characterization parameters as well as the techniques most commonly employed. Size/Size Distribution: PCC-1 Batch-mode dynamic light scattering; PCC-6 Atomic force microscopy; PCC-7 Transmission electron microscopy; PCC-10 Differential mobility analysis; PCC-15 High-resolution scanning electron microscopy; PCC-20 Particle size and concentration using the Spectradyne nCS1; PCC-21 Particle size and concentration of metallic nanoparticles using single particle inductively coupled plasma mass spectrometry. Solution Properties: PCC-12 Electrolytic conductivity; PCC-13 pH. Surface Chemistry: PCC-2 Zeta potential; PCC-16 Quantitation of PEG on PEGylated gold nanoparticles using reversed phase high performance liquid chromatography and charged aerosol detection; PCC-17 Quantitation of surface coating on metallic nanoparticles using thermogravimetric analysis. Chemical Composition: PCC-8 Inductively coupled plasmas mass spectrometry of gold in rat tissue; PCC-9 Inductively coupled plasmas mass spectrometry of gold in rat blood; Supplement to PCC-8 and PCC-9; PCC-11 Mass fraction of gold using inductively coupled plasmas optical emission spectrometry; PCC-14 Free vs. chelated gadolinium using hyphenated chromatography methods; PCC-18 Quantitation of active pharmaceutical ingredients in polymeric prodrug products; PCC-22 Residual organic solvent analysis in nanoformulations using headspace gas chromatography; PCC-23 Quantitation of residual DMSO in nanoformulations using gas chromatography with direct injection and flame ionization detection; PCC-24 Determination of water content using the Karl Fischer coulometric method. Nanoparticle Concentration: PCC-20 Particle size and concentration using the Spectradyne nCS1; PCC-21 Particle size and concentration of metallic nanoparticles using single particle inductively coupled plasma mass spectrometry. Particle Fractionation: PCC-19 Asymmetric-flow field-flow fractionation.
