[(9-oxo-9H-thioxanthen-2-yl)oxy]acetic acid

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:

29 November 2018 to 17 December 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Version / remarks:

2009

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 187,“Particle Size Analysis by Laser Diffraction”

Version / remarks:

Handbook K, 2007

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

Laser scattering/diffraction

Type of particle tested:

primary particle

Type of distribution:

volumetric distribution

Specific details on test material used for the study:

Appearance: Yellow powder
Purity / composition: 98.25%, assumed 100% for testing
Test item storage: At room temperature protected from light, desiccated

Mass median aerodynamic diameter:

8.27 µm

Geometric standard deviation:

2.641

Key result

Percentile:

D10

Mean:

1.5 µm

St. dev.:

0.012

Key result

Percentile:

D50

Mean:

6.66 µm

St. dev.:

0.038

Key result

Percentile:

D90

Mean:

16.6 µm

St. dev.:

0.086

Table 9:1 : Full Test Results
	Run 1	Run 2	Run 3	Run 4	Run 5	Average	STDVP	% STDVP
VWM	8.22	8.35	8.37	8.36	8.34	8.33	N/A	N/A
Mode	8.48	8.5	8.36	8.38	8.3	8.40	N/A	N/A
d10	1.48	1.51	1.49	1.51	1.51	1.50	0.0123	0.822
d50 (Median)	6.64	6.72	6.63	6.68	6.64	6.66	0.0377	0.566
d90	16.5	16.7	16.7	16.6	16.5	16.6	0.0857	0.516
MMAD	8.24	8.34	8.23	8.29	8.25	8.27	0.042	0.5
GSD	2.638	2.639	2.653	2.64	2.633	2.641	0.007	0.3

All particle size results are in µm

70.10 % by volume of sample was seen to be < 10.00 µm

Definitions

VWM : volume weighted mean

d10 : 10 % of the test item is less than this particle size

d50 : 50 % of the test item is less than this particle size

d90 : 90 % of the test item is less than this particle size

GSD : geometric standard deviation of the lognormal particle size distribution

MMAD : mass median aerodynamic diameter

Average : calculated from the entirety of the data captured in each run and not a

simple arithmetic mean

STDVP : standard deviation of the population

% STDVP : percentage standard deviation of the population

The 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 is within the acceptable limits as per the ISO 13320-1 test standard.

Conclusions:

The particle size was analysed over the range 0.01 µm to 3500 µm.

Executive summary:

The results of the laser diffraction test conducted to determine the particle size of CMTX 2-carboxymethyloxy-thioxanthone are summarised in the table below. The analysis was conducted using the dry powder module.

Summary of results

Particle size analysis using dry powder module	Average (µm)
Volume weighted mean	8.33
Mode	8.40
d10 (10 % of material is <)	1.50
d50 (50 % of material is <) (median)	6.66
d90 (90 % of material is <)	16.6
MMAD (mass median aerodynamic diameter)	8.27
Volume of sample < 10.00 µm	70.10%

Description of key information

Study conducted to recognised testing guidelines with GLP certification.

Additional information

Particle size analysis using dry powder module	Average (µm)
Volume weighted mean	8.33
Mode	8.40
d10 (10 % of material is <)	1.50
d50 (50 % of material is <) (median)	6.66
d90 (90 % of material is <)	16.6
MMAD (mass median aerodynamic diameter)	8.27
Volume of sample < 10.00 µm	70.10%