N-benzoyl-5'-O-[bis(4-methoxyphenyl)phenylmethyl]-2'-deoxyadenosine

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:

2017-12-18 to 2018-02-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 110 (Particle Size Distribution / Fibre Length and Diameter Distributions - Method A: Particle Size Distribution (effective hydrodynamic radius)

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 187: Particle Size Analysis by Laser Diffraction

GLP compliance:

no

Type of method:

Laser scattering/diffraction

Type of particle tested:

agglomerate

Type of distribution:

volumetric distribution

Specific details on test material used for the study:

The sample was tested after removing coarse particles with a sieve (mesh size: 1000 µm). No further preliminary treatment such as drying or milling was performed.

Mass median aerodynamic diameter:

29.9 µm

Percentile:

D50

Mean:

29.9 µm

Remarks on result:

other: Standard deviation not reported

Percentile:

D10

Mean:

8.1 µm

Remarks on result:

other: Standard deviation not reported

Percentile:

D90

Mean:

153.2 µm

Remarks on result:

other: Standard deviation not reported

The test item consisted of sticky particles which tended to agglomeration influencing the results of the study using laser diffraction. The test item was sieved with a mesh size of 1000 µm. Only 29% (w/w) of the test item passed the sieve and only this fraction was measured with laser diffraction.

Median particle size D (v, 0.5): 50% of particle volume or particle mass with lower particle diameter

1st test series: 31.3 µm

2nd test series: 28.4 µm

Average of the median particle size: 29.9 µm

Particle size D (v, 0.1): 10% of particle volume or particle mass with lower particle diameter

1st test series: 8.4 µm

2nd test series: 7.9 µm

Average of the particle size: 8.1 µm

Particle size D (v, 0.9): 90% of particle volume or particle mass with lower particle diameter

1st test series: 171.1 µm

2nd test series: 135.3 µm

Average of the particle size: 153.2 µm

The particle size distribution showed a polymodal distribution. The first maximum was observed at approx. 1 µm. The second and largest maximum occurred at approx. 20 µm and a third maximum at approx. 1000 µm. The second maximum corresponds to the size of the primary particles apparent in a microscopic image of the fine fraction.

Conclusions:

The particle size distribution of the test item was determined by laser diffraction (light scattering):
Average of the median particle size D (v, 0.5): 29.9 µm
Average of the particle size D (v, 0.1): 8.1 µm
Average of the particle size D (v, 0.9): 153.2 µm

Executive summary:

The particle size distribution of the test item was determined by laser diffraction (light scattering). The sample contained a significant amount of large agglomerates and the particles had a sticky behaviour. Hence, the sample was sieved. Only the fine fraction was analysed by laser diffraction and therefore, the results only characterise the fine fraction with a particle size below 1000 µm that amounts 29% (w/w) of the sample.

Average of the median particle size D (v, 0.5): 29.9 µm

Average of the particle size D (v, 0.1): 8.1 µm

Average of the particle size D (v, 0.9): 153.2 µm

Description of key information

The particle size distribution of the test item was determined by laser diffraction (light scattering). The sample contained a significant amount of large agglomerates and the particles had a sticky behaviour. Hence, the sample was sieved. Only the fine fraction was analysed by laser diffraction and therefore, the results only characterise the fine fraction with a particle size below 1000 µm that amounts 29% (w/w) of the sample.

Average of the median particle size D (v, 0.5): 29.9 µm

Average of the particle size D (v, 0.1): 8.1 µm

Average of the particle size D (v, 0.9): 153.2 µm