| Author(s): |
Vytautas Reipa; Geoffrey Purdum; Jonghoon Choi; |
| Title: |
Measurement of Nanoparticle Concentration Using Quartz Crystal Microgravimetry |
| Published: |
December 16, 2010 |
| Abstract: |
A common issue, encountered in nanoparticle-biological system interaction studies is accurate nanoparticle concentration expression, given the critical importance of the dose-response relationships. We present here the application of quartz crystal microgravimetry (QCM) to accurately measure nanoparticle concentration in a colloidal suspension. Application of a small drop of the nanoparticle suspension in volatile solvent to the crystal surface leaves a dry nanoparticle residue after solvent evaporation and a shift in the crystal resonant frequency is recorded. Instrument was calibrated using a dilution series of Si and Ag nanopowder in methanol, rhodamine B in methanol and ferrocene in cyclohexane. The QCM showed a linear response for nanoparticle concentrations in the range from 5 to 1300 g/ml. Method was used to determine the molar concentrations of size selected octyl-terminated Si nanocrystal samples with diameters in the range from 1.1 to 14.8 nm and calculate size dependent nanocrystal extinction coefficients. |
| Citation: |
Journal of Physical Chemistry B |
| Volume: |
114 |
| Issue: |
49 |
| Pages: |
pp. 16112 - 16117 |
| Keywords: |
Nanoparticles, concentration, colloidal solution, extinction coefficient, dry mass, quartz crystal microbalance |
| Research Areas: |
Chemistry |
| PDF version: |
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