Product Overview and Target Biology

The SARS-CoV-2 Nucleoprotein Mouse Monoclonal Antibody (Ab350703) targets the nucleocapsid (N) protein of SARS-CoV-2, the causative agent of COVID-19. The N protein is the most abundantly expressed viral protein during infection and plays essential roles in packaging the viral RNA genome, regulating viral transcription, and modulating host immune responses.

Because of its high expression level and relative sequence conservation among betacoronaviruses, the N protein is a primary antigen of choice for diagnostic assays, seroprevalence studies, and basic virological research. A mouse-derived monoclonal antibody offers the consistency, specificity, and reproducibility required for quantitative and semi-quantitative detection workflows.

Catalog SKU: Ab350703 | Lot reference: absea#KC-445 | Formulation: PBS only.

Recommended Applications and Protocol Guidelines

Mouse monoclonal antibodies against the SARS-CoV-2 N protein are broadly applied in the following research contexts. Always validate the antibody in your specific assay system before committing to large-scale experiments.

• Enzyme-Linked Immunosorbent Assay (ELISA): Use as a capture or detection antibody in sandwich ELISA formats to quantify N protein in cell lysates, culture supernatants, or patient-derived samples (research use only). Typical starting dilutions for detection antibodies range from 1:1,000 to 1:5,000; optimize empirically.
• Western Blotting (WB): Denature samples under reducing conditions and probe nitrocellulose or PVDF membranes. The SARS-CoV-2 N protein has an apparent molecular weight of approximately 46–50 kDa; confirm with a positive control lysate.
• Immunofluorescence (IF) / Immunocytochemistry (ICC): Use on fixed and permeabilized cells infected with SARS-CoV-2 or transfected with N-protein expression constructs. Pair with a species-appropriate secondary antibody conjugated to a fluorophore of choice.
• Immunohistochemistry (IHC): Apply to formalin-fixed, paraffin-embedded (FFPE) tissue sections following antigen retrieval. Optimize antigen-retrieval method and antibody concentration for each tissue type.
• Lateral Flow Assay (LFA) development: Mouse mAbs are commonly conjugated to colloidal gold or colored latex beads for rapid antigen-detection strip development.

Note: Specific validated dilutions, buffers, and controls are not confirmed in current source material. Refer to the product datasheet (absea#KC-445) or contact Aladdin Scientific technical support for application-specific recommendations.

Storage, Handling, and Stability

Proper storage and handling are critical to maintaining the activity and specificity of monoclonal antibodies supplied in PBS-only formulations (i.e., without carrier proteins such as BSA or preservatives such as sodium azide).

• Short-term storage (up to 4 weeks): Store at 2–8 °C.
• Long-term storage: Aliquot into single-use volumes and store at −20 °C or below. Avoid repeated freeze-thaw cycles, which can cause aggregation and loss of binding activity.
• Avoid: Exposure to temperatures above 37 °C, direct light (especially for fluorophore-conjugated derivatives), and repeated temperature cycling.
• Working solutions: Prepare fresh dilutions in an appropriate assay buffer (e.g., PBS with 1% BSA for ELISA). Do not store diluted antibody for extended periods.
• Sterile filtration: The PBS-only formulation is typically sterile-filtered (0.2 µm); confirm on the Certificate of Analysis.

All storage recommendations above reflect general best practices for PBS-formulated mouse mAbs. Confirm exact conditions on the product datasheet for Ab350703 / absea#KC-445.

Quality, Specificity, and Cross-Reactivity Considerations

When selecting and qualifying any monoclonal antibody for research use, consider the following quality attributes:

• Specificity: Confirm that the antibody detects SARS-CoV-2 N protein specifically and assess potential cross-reactivity with related coronaviruses (e.g., SARS-CoV-1, MERS-CoV, seasonal coronaviruses HCoV-NL63, HCoV-229E, HCoV-OC43, HCoV-HKU1). Cross-reactivity data should be available on the product datasheet; contact Aladdin Scientific if not listed.
• Lot-to-lot consistency: Request a Certificate of Analysis (CoA) for lot absea#KC-445 to confirm protein concentration, purity, and QC test results.
• Endotoxin levels: For cell-based or in vivo applications, verify endotoxin content (typically <1 EU/mg for research-grade mAbs).
• Isotype: Knowing the mouse IgG isotype (e.g., IgG1, IgG2a) helps select the correct isotype control and secondary antibody for your assay.
• Functional validation: Always include a positive control (recombinant SARS-CoV-2 N protein or N-protein-expressing cell lysate) and a negative control (irrelevant isotype-matched mAb) in every experiment.

Specific isotype, clone name, purity grade, and cross-reactivity data are not confirmed in the current source material. Flag for datasheet review.