USP 88 In Vivo Biological Reactivity Testing
Achieve the industry-standard USP Class VI certification. Our expert in vivo testing evaluates the systemic and local effects of your polymeric materials to ensure peak safety and regulatory compliance.
While in vitro methods like USP <87> provide an initial screen, USP <88> is the definitive standard for assessing how a material interacts with a living system. This chapter classifies plastics into six classes (Class I through VI) by evaluating the physiological response to material extracts and the material itself. At EBI, we conduct these studies with the highest ethical standards and technical precision.
Systemic Injection Test
Objective: To evaluate systemic (whole-body) responses to material extracts.
This test determines if chemicals leaching from your device could cause toxic effects when circulating through the body. We use healthy albino mice and different extraction vehicles to capture all potential contaminants.
- Procedure: Extracts are injected intravenously or intraperitoneally.
- Observation Period: 72 hours.
- Safety Criteria: Animals are monitored for weight loss, abnormal behavior (convulsions/prostration), or mortality. The sample passes if the biological reactivity is not significantly greater than the blank control.
- Turnaround: 6 weeks.
Intracutaneous Test
Objective: To evaluate local tissue responses to material extracts.
This assay specifically looks for irritation, inflammation, or localized toxicity at the site of contact. It is a critical component for any material that will have prolonged contact with skin or mucosal membranes.
- Procedure: Extracts are injected intracutaneously into the back of healthy albino rabbits.
- Observation Period: 24, 48, and 72 hours.
- Scoring: Our experts rate erythema (redness) and edema (swelling) on a numerical scale.
- Safety Criteria: The difference between the mean score of the Sample and the Blank must be 1.0 or less for a „Pass” result.
- Turnaround: 4 weeks.
Implantation Test
Objective: To evaluate the local pathological response of living tissue in direct contact with the material.
The implantation test is the most rigorous local assessment, simulating the real-world use of implants and high-risk medical devices. We offer two specialized routes:
A. Intramuscular Implantation (Rabbits)
- Method: Strips of the test material are surgically implanted into the paravertebral muscle.
- Evaluation: After 120 hours, the tissue is macroscopically examined for hemorrhage, necrosis, discoloration, and encapsulation.
B. Subcutaneous Implantation (Rabbits)
- Method: Samples are placed in subcutaneous pockets lateral to a dorsal incision. While rats may be used in specific cases, our standard protocol utilizes rabbits for this assessment.
- Evaluation: After a minimum of 7 days, the tissue in direct contact with the sample is examined using a magnifying lens and auxiliary light.
- Safety Criteria: The macroscopic reaction is compared against a USP High-Density Polyethylene (HDPE) control. The difference in scores must not exceed 1.0.
Sample & Ethical Requirements
As these tests involve animal models, EBI adheres to rygorous ethical guidelines and requires specific sample preparation:
- Ethical Readiness: All studies are conducted under existing, comprehensive ethical approvals, allowing for a streamlined transition from sample reception to testing.
- Animal Welfare: Testing is conducted by trained specialists to ensure minimal distress and maximum data reliability.
- Sample Requirements: Quantities are determined individually based on the material type and the specific Class (I-VI) required.
Why Choose EBI for USP 88?
- Class VI Certification: We provide the full suite of data required to label your material as USP Class VI Compliant.
- ISO 17025 Accredited: Our laboratory results are internationally recognized by regulatory bodies and biopharmaceutical partners.
- Integrated Reporting: We combine USP <87> and USP <88> data to give you a complete biological safety profile.
How We Work
Discovery & Insight
We begin with an in-depth consultation to understand your needs, challenges, and objectives. This helps us define the right strategy and scientific approach for your project.
Design & Development
Our experts translate your vision into actionable plans — combining innovative research, data, and technology to build precise and reliable solutions.
Delivery & Support
We implement the solution with full transparency and ongoing communication. After delivery, we stay involved — supporting you with optimization, updates, and future improvements.
FAQ: Frequently Asked Questions
What is the difference between Class I and Class VI?
The classes (I-VI) are determined by which tests and extracts are performed. Class VI is the most comprehensive, requiring all three tests (Systemic, Intracutaneous, and Implantation) using all four extraction vehicles.
Why is the turnaround time 4–6 weeks?
This includes the mandatory observation periods (up to 7 days for implantation) and the time required for ethical review boards to approve the study protocol, ensuring compliance with animal welfare regulations.
Can I use these results for MDR/CE Marking?
While USP <88> is highly respected, the ISO 10993 series is the primary requirement for CE Marking. However, USP Class VI data is often used as supporting evidence and is a prerequisite for most biopharmaceutical manufacturing components.
What is the difference between Class I and Class VI?
The classes (I-VI) are determined by which tests and extracts are performed. Class VI is the most comprehensive, requiring all three tests (Systemic, Intracutaneous, and Implantation) using all four extraction vehicles.
Why is the turnaround time 4–6 weeks?
This includes the mandatory observation periods (up to 7 days for implantation) and the time required for ethical review boards to approve the study protocol, ensuring compliance with animal welfare regulations.
Can I use these results for MDR/CE Marking?
While USP <88> is highly respected, the ISO 10993 series is the primary requirement for CE Marking. However, USP Class VI data is often used as supporting evidence and is a prerequisite for most biopharmaceutical manufacturing components.
Contact with us
We’re open to collaboration and research partnerships. Fill out the form — our team will respond as soon as possible.
Location:
Europejski Instytut Biomedyczny sp. z o.o.
ul. Bartycka 63A lok. 6, 00-716 Warszawa
Mail:
contact@ebi.bio
Phone:
+48 22 780 06 32
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