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Particle Counting
USP <788> sub-visible particulate matter counting for injectable products.
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Compendial standard this method is validated to.
Business days from sample receipt to report.
WHY YOU NEED IT
Why Particle Counting Matters
Detect what the eye can't
USP <788> counts sub-visible particles down to 10 and 25 µm — too small to see, but still a patient risk.
Limit the particle load
Sub-visible particulates are linked to vascular and immune reactions; <788> holds product to defined per-container limits. || Needs revision - per container limits and per size limits are the driving force || particles/volume limit goes down as volume goes up
Objective, numeric data
Light-obscuration counting gives quantitative particle results instead of a subjective pass/fail judgment.
OUR PROCESS
How we run this test for you
Method Suitability
Proving the method first
Before any lot release, we validate that the test method performs reliably for your product — the compliance step that comes first. ||||| very good for formulation development, useful for checking for aggregates
0 vials / N/A
Lot Release
Releasing every batch
Our core service — we run the test on each lot so you can release the batch to patients with confidence.
N/A
Stability Studies
Across your stability timeline
The same test run at each stability timepoint — for example, to support a longer beyond-use date (BUD).
10 vials if fill volume is less than 25 mL. || or 25 ml worth of material ||| 25 ml is min.
TECHNOLOGY
Counting particles too small to see.
01
Prepare and degas
The sample is mixed and degassed so air bubbles aren't miscounted as particles.
02
Light-obscuration count
The sample passes through a light-obscuration sensor that counts and sizes particles at the ≥10 µm and ≥25 µm thresholds.
03
Average and compare
Replicate runs are averaged and the per-container counts are compared to the <788> limits.
OUR SERVICES
Learn About Other Services
STABILITY STUDIES
Planning a stability study?
See how this test can support a validated stability program and the data needed for extended beyond-use dating.
✓
Stability-indicating HPLC methods that separate API from degradation products
✓
Custom study designs for refrigerated, frozen and room-temperature storage conditions
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Defined pull points with potency, pH, appearance and container-closure assessment
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Documentation packages to support extended beyond-use dating under USP <797>
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Sterility and endotoxin testing integrated at study end points
Guide: USP <797> stability studies & extended beyond-use dating →
Request a Stability Study Quote
Starting at $10,000
CATEGORY 2
CATEGORY 3
These studies generate the stability data required to qualify for the extended beyond-use dates that USP <797> permits for Category 2 and Category 3 CSPs — going well beyond the default short-dating limits.
TYPICAL STUDY OUTLINE
What a stability program covers
Supports
USP <797> Cat 2 & Cat 3 extended BUD
Storage conditions
Refrigerated · Frozen · Controlled RT
Pull points
T0, then defined intervals to BUD
Assays per point
Potency · pH · Appearance
Method type
Stability-indicating HPLC
End-point testing
Sterility · Endotoxin
Deliverable
BUD support documentation
COMMON QUESTIONS
Frequently Asked Questions
RELATED INFO
Relevant Resources
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Tell us what you need tested
Whether you need testing guidance, a quote, or just have questions — we’re here. A scientist will follow up within one business day.
USP methods verified for suitability, alternatives validated
Response within one business day
No obligation — guidance and quotes welcome
For service requests, quotes, or technical questions, email our support team.
info@saphobio.com
Phone
Available Monday to Friday, 9:00 AM – 6:00 PM (Pacific Time).
Text us: +1 (929) 437-6148
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