Days Set Up
Varies; test performed twice per week
Analytic Time

2 days

MiChart Code
Misc Quest Diagnostics-Nichols (Sendout)
Soft Order Code

Test Updated:


Transcobalamin Vit B12 Carrier Protein
Transcobalamin Vit B12 Carrier Protein
B12 Combining Capacity
B12 Combining Capacity

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All specimens should be accompanied by a requisition.

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MLabs provides all the supplies necessary for the collection of specimens.

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Test Overview

Test Methodology

Radiobinding Assay

Test Usage

Evaluation of conditions affecting vitamin B12 by altering the normal amounts of vitamin B12 binding protein, e.g., pregnancy.

Reference Range

650 - 1340 pg/mL

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Onsite

Collect blood in a red top tube from a fasting patient.

Collection Offsite

Collect blood in a red top tube from a fasting patient. Centrifuge, aliquot serum into plastic vial and freeze. Recently administered radioisotopes will interfere with this assay.

Red Top Tube
Normal Volume
1 ml serum
Minimum Volume
0.2 ml serum

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.