Characterization of an active ingredient made of nanoscale iron(oxyhydr)oxide for the treatment of hyperphosphatemia

Abstract

The combination of different analytical methods, supported by TEM, DLS, SAXS, Mössbauer spectroscopy, and SQUID, allows more accurate characterization of a new nanoscale active ingredient based on iron(oxyhydr)oxide against hyperphosphatemia.

Pilot-scale co-precipitation synthesis of a novel active ingredient made of ultrasmall iron (oxyhydr)oxide nanoparticles for the treatment of hyperphosphatemia

“…The further steps of section (b) are consistently performed according to the procedure of the laboratory process. 24 Upscaling of the further steps is part of further studies. 25,26 2.2.1 Co-precipitation synthesis of the active ingredient nanoparticles in different scales.…”

“…2.3.2 Chemical composition. The composition of the active ingredient was determined according to Spicher et al and Bäumler et al 24,25 The content of gum arabic b(gum arabic) and sodium b(Na) was measured by inductively coupled plasma mass spectrometry as previously described by Bäumler et al 24 We used a 7700 series ICP-MS system (Agilent Technologies) equipped with an ASX-520 autosampler (Agilent Technologies) and a micro mist nebulizer (Agilent Technologies). The system operated with 0.3 rps peristaltic pump speed, 1550 W plasma power, and 15 L min −1 ow rate of the argon carrier gas.…”

“…2.3.5 Mössbauer spectroscopy. Mössbauer spectroscopy was measured according to Bäumler et al 24 in transmission geometry with a standard electromechanical spectrometer (Halder Elektronik) using a source of 57 Co in rhodium and a sinusoidal velocity waveform. Calibration was performed with an a-iron foil at room temperature.…”

“…The spectra were leastsquare tted with Gaussian distributions of quadrupole splitting for 300 K spectra and hyperne elds for 4.2 K-spectra. The data evaluation was carried out as described by Bäumler et al 24 2.3.6 Dynamic light scattering. A Zetasizer Ultra (Malvern Panalytical GmbH) was used for determining the particle size distribution by dynamic light scattering (DLS).…”

“…46 However, it has already been shown in a preliminary study that XRD analyses are challenging for this active ingredient due to the ultrasmall particle size and the low crystallinity. 24 Instead, Bäumler et al applied Mössbauer spectroscopy, among other methods, to further characterize the iron (oxyhydr)oxide core of this compound. 24 To obtain information on the environment of the iron ions and thus derive conclusions on potential changes in the crystal structure, we also investigated the active ingredient samples produced on the 100 L scale with this method (see Fig.…”