N-(2-hydroxyethyl)stearamide

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From March 28, 2012 to March 29, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: ISO 13320:2009

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 187

Deviations:

not specified

Principles of method if other than guideline:

The particle size distribution analysis was conducted using the small volume (wet) module (SVM) with silicone oil as the dispersant and the laser diffraction as an analyser.

GLP compliance:

yes (incl. QA statement)

Type of method:

Laser scattering/diffraction

Type of distribution:

volumetric distribution

Specific details on test material used for the study:

- Name of test material (as cited in study report): Amides, C16-18 (even-numbered), N-hydroxyethyl
- Molecular formula: C20H41NO2
- Molecular weight: 327.54 g/moL
- Physical state: Cream powder
- Analytical purity: Not indicated by sponser, indicated as 100% pure
- Lot/batch No.: 5103033
- Expiration date of the lot/batch: January 11, 2013 (allocated by NOTOX, 1 year after receipt of the test substance)
- Storage condition of test material: At room temperature in dark
- Relative density: 0.997

Mass median aerodynamic diameter:

290.18 µm

Key result

Percentile:

D50

Mean:

290.18 µm

St. dev.:

2.19

Key result

Percentile:

D10

Mean:

< 128.084 µm

St. dev.:

0.93

Key result

Percentile:

D50

Mean:

< 290.617 µm

St. dev.:

2.19

Key result

Percentile:

D90

Mean:

< 591.66 µm

St. dev.:

4

Results of visual microscopy:

-Standard visual observation

Sample observed to be a free flowing, medium size powder.

-Observation at 100 x magnification

The particles appeared to be near spherical shaped crystals. The smallest individual particle size was approximately 10 μm and the largest individual size was approximately 198 μm.

-Observation at 400 x magnification

The sample was observed to be made up of single crystalline particles.

Results of laser diffraction analysis:

Table 1: Full test results:

	Run 1	Run 2	Run 3	Run 4	Run 5	** Average
Volume weighted Mean	342.829	316.414	338.067	324.737	324.728	329.355
Median (d.50)	299.954	281.763	295.349	286.621	290.468	290.617
Mode (µm)	312.093	294.443	302.893	297.407	305.077	301.936
*MMAD	299.504	281.34	294.906	286.191	290.032	290.18
10 % of material is <	128.758	126.342	129.747	127.198	128.426	128.084
50 % of material is <	299.954	281.763	295.349	286.621	290.468	290.617
90 % of material is <	623.841	560.15	614.428	582.41	578.442	591.66

All results are in μm

* Mass Median Aerodynamic Diameter

** Average result is calculated from the entirety of data captured in each run and is not a simple arithmetic mean.

0.0 % by volume of sample was seen to be <10.00 μm.

Table 2: Standard deviations:

Run No.	1	2	3	4	5	STDVP	% STDV
d10	128.758	126.342	129.747	127.198	128.426	1.2	0.93
d50	299.954	281.763	295.349	286.621	290.468	6.38	2.19
d90	623.841	560.15	614.428	582.41	578.442	23.69	4
d15.78	158.134	153.881	158.113	154.79	156.601	1.72	1.1
*GSD	1.897	1.831	1.868	1.852	1.855	0.02	1.17
MMAD	299.504	281.34	294.906	286.191	290.468	6.37	2.19

Coefficient of variation for d50 is less than 3%; d10 and d90 are less than 5%. Thus repeatability of the characteristic particles in the size distribution are within the acceptable limits as per the ISO 13320-1 test standard.

-For results of the solubility and dispersability test for particle size analysis, refer to the attached background material.

Conclusions:

Under the test conditions the particle size (i.e., the MMAD) of the test substance is determined to be 290.18 μm using the laser diffraction analysis.

Executive summary:

A study was conducted to determine the particle distribution of the test substance according to the methods of ISO 13320:2009 and CIPAC MT 187. The analysis was conducted using the small volume (wet) module (SVM) with silicone oil as the dispersant and the laser diffraction as an analyser (over the range 0.02 μm to 2000 μm). Under the test conditions, the particle size (i.e., the MMAD) of the test substance was determined to be 290.18 μm.

Description of key information

The particle size distribution was determined according to ISO Method 13320 (2009) and CIPAC Method MT 187 (Livingston, 2012).

Additional information

The particle size (i.e., the median mass aerodynamic diameter (MMAD)) was determined to be 290.18 μm.