HORIBA Application Note

Introduction

Mono-disperse polystyrene latex (PSL) standards are commonly used to verify accuracy and proper operation of laser diffraction particle size analyzers. As these materials are somewhat different from normal materials, proper conditions and procedures are necessary to ensure correct results.

Analytical Test Method

Applicable Instrument

LA-960V2

Dispersant Fluid

RO water

Basic Measurement Conditions

Sample Information

• Sample Name: (nominal size of standard)
• Material: PSL
• Source: (name of vendor)
• Lot Number: (found on bottle)
• Refractive Index: Single PSL in water
• Form of Distribution: Manual
• Iteration Number: 1000
• Distribution Base: Volume

Advanced Measurement Conditions

Measurement tab

• Data acquisition times (Sample): 5000
• Data acquisition times (Blank): 5000
• Alignment before measurement: Yes

Test Procedure

1. Feed the LA-960V2 with RO water.
2. Activate circulation and agitation.
3. De-bubble.
4. Align the laser and verify that the cell is clean by inspecting the channel baseline for any channels reading below 500.
5. Take the system Blank.
6. Add sample.
7. Take 5 measurements.
8. Rinse the LA-960V2 with RO water.

Results

Verify that the Mean Diameter is within 5% of the published value for each test. The following are the results of 2 µm and 2.5 µm PSL standards on the 2 different units of LA-960V2. All data are in the bottle tolerance values without additional 5%.

2 µm PSL Standards

The particle size distribution graph displays a dominant peak around 2 micrometers (µm), characteristic of a mono-disperse sample.

Product Details

• Catalog Number: 4202, Duke Standards, Microsphere Sizer Standards
• Packaging Lot #: 282917
• Certified mean diameter: 2.020 µm
• Expanded uncertainty: +/-0.015 µm

2.5 µm PSL Standards

The particle size distribution graph displays a dominant peak around 2.5 micrometers (µm), characteristic of a mono-disperse sample.

Product Details

• Catalog Number: 4025A, Duke Standards, Microsphere Sizer Standards
• Packaging Lot #: 288145
• Certified mean diameter: 2.514 µm
• Expanded uncertainty: +/-0.027 µm