Surrogate Solutions for Visual Inspection
Project-specific surrogate formulations developed around selected optical and physical target attributes when actual product is unavailable, restricted, supply constrained, or unsuitable for routine study use.
What Are Surrogate Solutions?
A surrogate solution is a representative medium developed around selected product attributes that matter to a defined inspection study. Relevant attributes may include refractive index, color, clarity or opalescence, density, viscosity, interfacial behavior, particle motion, and container compatibility.
A surrogate may be useful when actual product is controlled, high value, supply constrained, development-stage, or subject to special storage or handling. It can support selected inspection development or qualification activities only when relevant properties, acceptance criteria, and limitations are defined for the intended use.
Development begins with available product information and measured target attributes. Analytical methods, acceptance criteria, compatibility, documentation, and customer verification responsibilities are agreed in the project scope; a Certificate of Analysis alone does not establish inspection equivalence.
Properties We Evaluate and Target
The relevant property set is selected from the intended inspection use. Not every attribute is equally important for every product, package, defect, or method.
Index of Refraction
Refractive index may affect particle contrast and light scattering. The target and tolerance should be measured and justified for the intended study rather than assumed to guarantee identical visibility.
Density & Viscosity
Density and viscosity can influence settling and movement. Candidate formulations can be assessed against agreed target ranges and the site's intended handling method.
Color & Clarity
Color, clarity, and opalescence may affect contrast and inspectability. The project should define how visual appearance will be compared and what degree of representativeness is needed.
When Do You Need a Surrogate Solution?
Controlled Substances
DEA-scheduled products that cannot be used freely for validation activities due to regulatory restrictions on handling and disposal.
High-Value Biologics
Products where the cost per unit makes it impractical to consume hundreds of units for inspector qualification or equipment validation.
Cell & Gene Therapy Products
CGT products with extremely limited batch sizes, complex storage requirements, or patient-specific manufacturing.
Products with Special Storage
Formulations requiring cold chain, light protection, or other conditions that make them impractical for extended validation activities.
Pre-Launch Development
New products in development where commercial-scale material is not yet available but inspection processes must be validated.
Multi-Site Standardization
Organizations needing a consistent validation medium across multiple manufacturing sites without shipping actual product.
Potential Application Environments
Surrogate feasibility may be evaluated for these product and manufacturing environments, subject to product data, material compatibility, intended use, and agreed acceptance criteria.
Our Development Process
A controlled project can move from technical scoping to a documented candidate formulation and customer evaluation.
Technical Scope
Define intended use, available samples and data, relevant attributes, analytical methods, and target ranges.
Candidate Development
Develop one or more formulations around the agreed target profile and compatibility constraints.
Verification
Compare candidate results with the agreed methods, criteria, and product data; document material limitations.
Documented Delivery
Provide the formulation, agreed test results, handling information, and project-specific documentation package.
Need a Custom Surrogate Formulation?
Share the intended use, product attributes, container, study method, available samples, and timeline. We can assess feasibility and propose a target profile and documentation scope.