Standard Test Method for Particle Size Distribution of Chromatography Media by Electric Sensing Zone Technique (Withdrawn 2010)

SIGNIFICANCE AND USE
It is important to recognize that the results obtained by this test method or any other test method for particle size determination using different physical principles may disagree. The results are strongly influenced by physical principles used by each method of particle size analysis. The results of any particle sizing method should be used only in a relative sense and should not be regarded as absolute when comparing results obtained by other methods.
Both sellers and purchasers of chromatography media will find the test method useful if mutually acceptable to all parties concerned to determine the particle size distributions for materials specifications, manufacturing control, and development and research.
SCOPE
1.1 This test method is valuable for the measurement of particle size and covers determination of the particle size distribution of chromatography media in the overall size range of approximately 1 to 450 μm using the electric sensing zone (ESZ) apparatus. This instrument uses an electric current path of small dimensions that is modulated by individual particle passage through an aperture and produces individual pulses of amplitude proportional to the particle volume (1).²  
1.2 The values stated in SI units are to be regarded as the standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
WITHDRAWN RATIONALE
This test method is valuable for the measurement of particle size and covers determination of the particle size distribution of chromatography media in the overall size range of approximately 1 to 450 μm using the electric sensing zone (ESZ) apparatus. This instrument uses an electric current path of small dimensions that is modulated by individual particle passage through an aperture and produces individual pulses of amplitude proportional to the particle volume.
Formerly under the jurisdiction of Committee E48 on Biotechnology, this test method was withdrawn in February 2010 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

General Information

Status
Withdrawn
Publication Date
09-Nov-1995
Withdrawal Date
31-Jan-2010
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM E1772-95(2001) - Standard Test Method for Particle Size Distribution of Chromatography Media by Electric Sensing Zone Technique (Withdrawn 2010)
English language
3 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)


NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:E1772–95 (Reapproved 2001)
Standard Test Method for
Particle Size Distribution of Chromatography Media by
Electric Sensing Zone Technique
This standard is issued under the fixed designation E1772; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.1 equivalent volume diameter—the diameter of a sphere
with a volume equal to that of the actual particle.
1.1 This test method is valuable for the measurement of
3.1.2 volume weighted (mass) median diameter—a number
particle size and covers determination of the particle size
C
distribution, n (d), is measured, and N 5 n (d)isthe
distribution of chromatography media in the overall size range (i 5 1 i
total number of particles in the C classes and n (d)isthe
of approximately 1 to 450 µm using the electric sensing zone i
number of particles in class i (corresponding to diameter d).
(ESZ) apparatus. This instrument uses an electric current path i
3.1.2.1 Discussion—From n (d), the corresponding volume
of small dimensions that is modulated by individual particle
distribution can be calculated:
passage through an aperture and produces individual pulses of
amplitude proportional to the particle volume (1). p
3 3 C 3
f~d ! 5 n~d ! d /V 5 n~d !d / n~d !d (1)
(
i i i i i i 5 1 i i
1.2 The values stated in SI units are to be regarded as the 6
standard.
where:
1.3 This standard does not purport to address all of the
p
C 3
safety concerns, if any, associated with its use. It is the
V 5 n~d !d (2)
(
i 5 1 i i
responsibility of the user of this standard to establish appro-
is the total particle volume.
priate safety and health practices and determine the applica-
A cumulative volume distribution, F(d), is defined by
i
bility of regulatory limitations prior to use.
F~d ! 5 f~x ! (3)
i ( i
x#d
i i
2. Referenced Documents
The volume weighted (mass) median diameter is the diameter, d ,
given by
2.1 ASTM Standards:
D1193 Specification for Reagent Water
F d 5 0.5 (4)
~ !
i
that is, the diameter that divides the particle volume into two equally
E177 Practice for Use of the Terms Precision and Bias in
sized halves.
ASTM Test Methods
E456 Terminology Relating to Quality and Statistics
4. Summary of Test Method
2.2 Other Document:
4.1 A carefully dispersed, dilute suspension of the particles
Manufacturer’s Operating Manual for Particle Size Distri-
in a beaker filled with electrolyte is placed in the counting
bution Analyzer
position on the instrument sample stand. The suspension is
3. Terminology
forced through a restricting aperture. Each particle passing is
recordedonanelectroniccounteraccordingtoselectedparticle
3.1 Definitions:
size levels.
4.2 The instrument determines the particle volume (liquid
This test method is under the jurisdiction of ASTM Committee E48 on
displacement); therefore, the equivalent spherical diameter is
Biotechnology and is the direct responsibility of Subcommittee E48.03 on Unit
commonly used to express the particle size.
Processes and Their Control.
Current edition approved Nov. 10, 1995. Published January 1996. DOI: 10.1520/
5. Significance and Use
E1772-95R01.
The boldface numbers in parentheses refer to the list of references at the end of
5.1 It is important to recognize that the results obtained by
this test method.
this test method or any other test method for particle size
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
determination using different physical principles may disagree.
Standards volume information, refer to the standard’s Document Summary page on
The results are strongly influenced by physical principles used
the ASTM website.
4 by each method of particle size analysis. The results of any
Available from Coulter Corp., Scientific Instruments, P.O. Box 169015, MC
195-10, Miami, FL 33116-9015. particle sizing method should be used only in a relative sense
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E1772–95 (2001)
andshouldnotberegardedasabsolutewhencomparingresults round-bottomedsamplebeaker.Addasuitabledispersingagent
obtained by other methods. and electrolyte solution and sonicate. Check the particle
5.2 Both sellers and purchasers of chromatography media concentration. It should be at 5 % coincidence (Table 1).
will find the test method useful if mutually acceptable to all 8.1.1 If the concentration is too high, dilute the sample with
parties concerned to determine the particle size distributions electrolyte solution. If the concentration is too low, prepare a
for materials specifications, manufacturing control, and devel- new sample starting with dry powder.
opment and research. 8.1.2 Ifthesampleisintheformofsuspension,thereshould
be enough space in the container to allow homogenization of
6. Apparatus
the suspension. Shake the container vigorously until the entire
6.1 Electronic Particle Counter, using the ESZ technique, suspension is homogenous. Immediately withdraw approxi-
mately 5 mL of suspension using a Pasteur pipette. Place the
for example, Multisizer II from Coulter Electronics Ltd.,
Elzone 280 from Particle Data Inc., or their equivalent. suspension in a round-bottomed sample beaker, and dilute
slowly with electrolyte solution. Sonicate for 1 min. Check the
6.1.1 The apertures are selectable from 50, 70, 100, 140,
280, 400, and 560-µm diameter. The measuring range for each particle concentration. Adjust if necessary.
sensor is approximately 2 to 80 % of the aperture diameter (2). 8.2 Calibration for Particles in Suspension—Wet sieve a
portion of the material under test in water with sieves that are
6.2 Microscope—ZeissAxioplanfromCarlZeiss,Germany,
or similar microscope. as close as possible together in size and with a size range that
covers the peak of the particle size distribution. Transfer the
6.3 Filtering Device—Peristalic pump with 0.22-µm mem-
brane filters (Sterivex-GS Millipore Corp.). sieved material to a suitable container, and substitute the water
for that electrolyte solution that shall be used when measuring
6.4 Ultrasonic Bath, 50 to 100 W and 60 to 80 kHz.
the material using the ESZ instrument. Transfer a suitable
7. Reagents
portion to a microscope slide, and cover with a cover slip.
Measure the diameters of at least 400 particles using the
7.1 Purity of Reagents—Reagent grad
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.