Quality Control and Standardization Development Strategies for Pathology Diagnostic Chips

Why quality control is key to the successful implementation of pathology diagnostic chips

Pathology diagnostic chips involve multiple steps such as tissue fixation, embedding, array preparation, probe immobilization, and reaction condition control. Fluctuations in any step may affect final signal interpretation. Compared with a single conventional section, a chip integrates multiple core spots on the same carrier, imposing higher requirements on carrier flatness, core spot integrity, sample positioning accuracy, and reaction uniformity. The goal of quality control is to ensure stable results across different batches, different operators, and different testing dates, providing pathology laboratories with a reliable analytical tool.

Common performance evaluation items

Manufacturers and testing laboratories generally need to focus on the following aspects:

Appearance and structure: The chip carrier has no obvious scratches or stains, and the core spots are neatly arranged, with no detachment or displacement.

Sample integrity: Tissue core spots have uniform thickness, and the preservation state of antigens or nucleic acids meets expectations, avoiding excessive fixation or degradation.

Reaction uniformity: Signal distribution is stable within the same core spot and among different core spots, and background is controllable.

Batch-to-batch consistency: Different production batches show consistent result trends under the same testing conditions.

Specificity and cross-reactivity: Acceptable binding characteristics for the target analyte, with non-target signals within a reasonable range.

The above items are generally evaluated using internal quality control materials, reference materials, or samples confirmed by pathologists, and do not involve commitments regarding specific clinical outcomes.

Standardization and documentation management

Standardization construction requires complete documentation from raw materials, preparation processes, storage and transportation, to use and operation. For raw materials such as tissue samples, informed consent, ethical review, and donor information protection must comply with relevant regulations; parameters such as fixative type, fixation time, and embedding temperature should have clear ranges; environmental conditions such as temperature, humidity, and cleanliness during chip preparation should be recorded. Manufacturers may refer to medical device quality management system requirements to establish processes for design and development, production control, product release, and post-market surveillance. Within laboratories, it is recommended to write standard operating procedures specifying sample receipt, chip pretreatment, staining or hybridization steps, signal acquisition, and interpretation standards.

Registration and compliance perspective

If a pathology diagnostic chip is intended to be marketed in China as an in vitro diagnostic reagent or medical device, the management category and registration pathway must be determined according to the product's intended use. Registration materials usually include product technical requirements, analytical performance evaluation, stability studies, clinical evaluation, etc. For chip products used only for research, they should be clearly labeled "for research use only" and must not be used for clinical diagnosis. Regardless of the intended use, companies should avoid absolute language in promotion, not claim to replace the gold standard of pathological diagnosis, and not promise specific detection rates or efficacy. Compliant promotion should objectively describe the product's performance boundaries and applicable scenarios.