Expertise & Lab Services / Pharmaceutical Analysis / USP <788> & <789>
USP <788>
USP <788> deals with particulate matter in injectable solutions. The tests are done via one of the two standard methods.
Method 1 uses light obscuration on a prescribed volume of solution and is the preferred testing method.
It works by passing the sample through the window of a sensor apparatus, and light from the laser beam is detected by a photomultiplier tube. Particulate count and size are inferred from the changing intensity of the laser light beam as the particles pass through it.
<788> USP limits for the light obscuration test
Volume ≥ 10 μm:
- 6000 per container for small volume injections
- 25 per container for large volume injections
Volume ≥ 25 μm:
- 600 per container for small volume injections
- 3 per milliliter for large volume injections
Method 2 uses a microscope. The sample is filtered through a microporous membrane and then physically counted on a compound binocular microscope. The microscopic approach is leveraged for samples that are oily, dark-colored, or surfactant where light obscuration cannot be done.
We use circular diameter graticules to compare particle sizes with the references and count those that are larger than 10 and 25 μm.
<788> USP limits for the microscopic test
Volume ≥ 10 μm:
- 3000 per container for small volume injections
- 12 per container for large volume injections
Volume ≥ 25 μm:
- 300 container for small volume injections
- 2 per milliliter for a container for large volume injections
We identify the nature of the particles.
The USP <788> tests are useful for identifying the amount of particulate matter in a product. We, however, take these tests further and analyze the nature of the foreign materials in your products. By helping our clients understand the nature of the contamination, they are better able to evaluate the potential risk to patients. Our <788> contaminant analyses help to:
- Identify the color, size and chemical nature of the contaminant
- Accelerate investigative analyses for the source of the contamination
- Guide product modification processes
- Improve regulatory compliance
