When this test applies
Any device whose surfaces contact a fluid path into the patient — catheters, infusion sets, syringes, implant delivery systems, blood-contacting devices — and any device for which a regulator or the FDA's particulate guidance for intravascular devices asks for particle counts. ISO 10993-1:2025 treats particulates as a physical characteristic to be evaluated; USP <788> supplies the method and the reference limits.
When to run it
On the finished, sterilised device in its final packaging, once the material, surface finish, cleaning and packaging are locked — each of those changes the particulate load. It is quick and inexpensive, and a high count early tells you about a cleaning or packaging problem before the biological studies run on the same lots.
What a pass tells you
Cumulative particle counts at 10 µm and 25 µm per device, reported against the USP <788> limits for the applicable dosage form or your device specification. A count below the limits is the pass condition; the raw distribution is reported so you can trend it.
What it does not tell you
Nothing about what the particles are — identification by microscopy or spectroscopy is a separate determination — and nothing about chemical extractables, endotoxin or any biological endpoint. The standard surface extraction represents fluid contact with the device surface; non-standard preparations and large sample volumes may need a custom approach at additional cost.
Method
Standard device surface extraction, flushing or immersing the fluid-contacting surfaces in particle-free water, followed by light obscuration particle counting per USP <788> Method 1 on the extract, with blanks to establish the background. Additional fees may apply for non-standard preparations and large sample quantities or volumes.
Where it runs
This method is domestically sourced (US). The laboratory is ISO/IEC 17025 accredited and GLP certified, and the report is issued under Groenakker’s ISO 13485:2016 certified quality system, in Groenakker’s report template or in your document template on request at no extra cost.
Usually ordered alongside
Bacterial endotoxin (GRK-7003-01), which is run on the same finished, packaged devices and addresses the other common manufacturing-related failure; cytotoxicity as the baseline biological screen; and chemical characterisation where the fluid path also raises extractables questions.
