Specimen Handling

Red Top Tubes Red top tubes contain no additives. Red top tubes must be allowed to clot completely (30-60 minutes) prior to centrifugation. Centrifuging the specimen yields serum. NOTE: All...

Read More

Chart of specimen tubes, the tube type, mixing instructions, and laboratory use.

Read More

When collecting multiple specimens, the order in which tubes are drawn can affect some test results. Avoid transferring anticoagulants among tubes by contamination of the stopper-puncturing needle. Below is a list of correct order of draw by Vacutainer or syringe method.

  1. Tubes for sterile specimens (Blood Cultures)

  2. Light Blue Top – Sodium Citrate (Coagulation)

  3. Gold Top – Serum Separator (Routine Chemistry)

  4. Red Top – Serum; No Additives (Therapeutic Drug Testing)

  5. Light Green Top – Lithium Heparin/Dark Green –Sodium Heparin (Plasma for Routine Chemistry)

  6. Lavender Top – EDTA (Hematology/Blood Bank)

Read More

The importance of proper specimen collection, labeling, handling, storage, and transport cannot be over-emphasized. If laboratory tests are to be accurate indicators of a patient’s state of health, these steps must be understood and followed precisely.

Correct Specimen Labeling

  • Specimens MUST be labeled in the presence of the patient.

  • ALL TUBES must be labeled with: Patient Name (Last, First), Date of Birth, and Date and Time of collection.

Read More

When centrifugation is required follow these instructions:

  1. Draw 5 mL of blood for each 2 mL of serum or plasma needed. Collect in the appropriate collection tube.

  2. If serum is required, allow the specimen to clot for at least 30 minutes, but no longer than 1 hour before centrifugation.

  3. Within 2 hours of collection, centrifuge for at least 15 minutes @ 3200-3500 RPM. For coagulation testing, refer to the NLL Directory of Services for more specific and stringent processing directions associated with coagulation sample requirements.

  4. Pipette the serum* or plasma into a plastic transport vial, taking care not to transfer red cells to the vial. Tighten the cap firmly to prevent leakage.

Note:  Serum drawn in a serum separator tube (Gold Top) does not need to be transferred to a plastic transport vial.

Read More

Instructions on how to collect a clean-catch urine specimen as well as how to collect a 24-hour urine specimen.

Read More

Maintaining specimen integrity is extremely important to laboratory testing. Please review our special instructions for handling specimens.

Read More

ALI staff often need to review smears made from the blood drawn for a CBC. Although not required, a properly prepared blood smear may be useful for specimens that will be more than 12 hours old when received.

The following instructions will assist you in the preparation of blood smears. Address any questions or concerns to the ALI Hematology Supervisor.


Pre-cleaned frosted glass slides, plain capillary tubes or applicator stick, and cardboard slide holders.



  1. Label a clean, dust-free slide with the patient's full name and the date.

  2. Using a plain capillary tube or applicator stick, place a drop of well-mixed blood 2-3 mm in diameter on the slide as illustrated.

  3. Hold the end of a second slide (spreader slide) against the surface of the first slide at an angle of 30 40 degrees; slide it back to make contact with the drop of blood.

  4. By capillary action, the blood will run across the end of the spreader slide.

  5. Quickly, smoothly, and evenly, move the spreader slide away from the drop. The resulting blood smear should be at least two-thirds of the length of the slide.

  6. The smear should have an even "feathered edge." Allow the smears to air dry completely. Once the smears are dry, place them in the cardboard slide holders, tape shut, and transport to ALI along with the EDTA blood.

Read More