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Sample Collection

  1. Verify to ensure that the sample is collected from the correct patient by checking for at least two identifiers, asking for the patient’s name, and NRIC number/Passport number, or address or date of birth, or by checking the patient’s wristband for name and NRIC number/Passport number.
  2. An adequate amount of the sample must be collected to enable the test to be carried out. If multiple tests are ordered, make sure that sufficient sample is collected. If the sample is insufficient, the authorised requestor should state which tests should be done in order of priority.
  3. Aseptic techniques must be employed during collection to prevent the introduction of micro-organisms into the patient’s anatomical space, and to prevent the sample from being contaminated during the process of collection.
  4. All samples should be regarded as potentially infectious and standard precautions guidelines should be followed by all healthcare workers during sample collection and handling.
    Samples must be collected into appropriate containers before despatch to the laboratory.
    Be careful to check for cracks in the containers and to ensure that the lids of containers are properly tightened to prevent leakage of samples during handling and transportation. This can pose infection hazards to transport and laboratory staff.
  5. Ensure that the outer surfaces of the containers are not contaminated by the patients’ samples.
  6. Please see Lab Disciplines (Special Instructions) of each discipline for more information including:
    • How to prepare patients before sample collection
    • When, how, where and how much material to collect
    • Types of containers used e.g. sterile, plain, with preservative, anticoagulant or transport media
    • Conditions of storage and transportation of samples to the laboratories

Vacutainer ® Sequence of Draw


DescriptionOrder of DrawTube ContentDraw VolumeDeterminationsInstructions
BACTEC Blood Cultures18 – 10 mL per bottleAerobic & Anaerobic CulturesBlood cultures should be done separately. However, if blood samples need to be taken, then blood cultures are done first to avoid contamination by the other blood tubes.

2Sodium Citrate2.7 mLPT/PTT PT/INR Platelets Function Test (PFT) (use 7 tubes for PFT)Allow tube to fill completely. Tube inversion x 4

3Plain6 mLAntibody identifications (Immunohaematology)Tube inversion x 5

4SST (Plain with Gel)5 mLFor Biochemistry tests (serum determinations)
Tube inversion x 5

5Lithium Heparin4 mLAmmonia (send in with ice-pack), HLAB27 (use 2 tubes), Cytogenetic investigationsTube inversion x 8

6K2EDTA 10.8 mg6 mLStrictly for Group X-MatchTube inversion x 8

7K2EDTA 5.4 mg3 mLFK506, Cyclosporin, G6PD, FBC, HbA1c, Homocysteine (send in with ice-pack)Tube inversion x 8

8Sodium Fluoride6 mLLactate (send in with ice-pack), Pyruvate, GTTTube inversion x 8
*CLSI: Clinical Laboratory and Standards Institute;
Reference: H3-A5 Vol. 23 No. 32 Replaces H3-A4 Vol. 18 No. 7

Blood Banking

  • Pre-transfusion Tests (Blood Group, Antibody Screen, Compatibility test)


  • Immunohaematology Tests including Antibody Identification

Summary of Guidelines on Specimen Collection


  1. Label all tubes and specimen bottles.
  2. State source of specimen(s) and test(s) required.
  3. Fill in patient location.
  4. Fill in doctor’s name.
  5. Fill in date of collection, and time.
  6. Use the appropriate bottle and tube.
  7. Use EDTA tubes for HbA1c. Some tests need special tubes and need to be sent in ice. Please refer to instructions on CPOE prompt or lab request forms (e.g. Clinical Biochemistry tests).
  8. PT/PTT tubes: Should fill to blue mark.
  9. FBC tubes: Should fill to white mark.


  1. Gram Stain and Culture
    (i) Gram stain and smear - use eSwab
    (ii) Aerobic Bacterial Culture - use eSwab
    If Gram Stain and aerobic bacterial culture are required, send 1 eSwab with separate orders for Gram stain and aerobic bacterial culture 
  2. Anaerobic culture: Use eSwab (use a separate eSwab from aerobic culture)
  3. Mycobacteria (TB, AFB) smear and culture                                                                                                                     
    (a) Send separate specimens (Sputum, Swab etc.) and requests if Mycobacteria (TB) and Bacteria are required.
    (b) Do not send laryngeal swab, send sputum instead and state the source of specimen.
  4. Neisseria gonorrhoeae (G.C.): Do not send the swab. Obtain G.C. plate from Client Services (Tel: 6321 4950/4952/4904), inoculate on plate and send back to the lab.


  1. Collect 1 mL of blood in each of the four Quantiferon tubes in the following order: Nil (Grey) ► TB1 (Green) ► TB2 (Yellow) ► Mitogen (Purple)
  2. Please check that the blood level is within the volume guide on the tubes. Recollect blood sample with a new tube if the tube is overfilled or underfilled.
  3. After blood collection, shake the tubes 10 times to mix the blood with the tube contents.
  4. Ensure that the specimen is able to reach CTBL within 16 hours of blood collection.
  5. Do not collect blood on Eve of Public Holidays, Saturdays, Sundays & Public Holidays.
Please click here for the blood taking instructions.


  1. Send blood specimens in BD Vacutainer Lithium Heparin tubes (green cap) to the Immunology & Serology Lab, Academia. Testing is by appointment only. Please call 6321 4960.
  2. Obtain samples in the morning, dispatch immediately to the laboratory, reaching the laboratory no later than 12 noon the same day.
  3. Testing is available only on Mondays to Thursdays. Testing is not available on Public holidays and eves of public holidays.
  4. Adults: 10 mL blood (3 tubes required), Children: 4 mL blood (1 tube required),
    Neutropenia: at least 20 mL blood (5 tubes required).       
  5. Invert tube contents 8 to 10 times to ensure the whole blood is mixed thoroughly with the anticoagulant.
  6. Do NOT refrigerate at any time. Store and transport only at room temperature (18 to 25oC), otherwise the WBC’s  will not be viable.
  7. Please deliver samples by hand or pneumatic tube. Do not use the telelift.
  8. Use the ‘Request for Immunological Investigations’ form, tick ‘others’ and write T-spot.TB.


All specimens are to be accompanied by barcode labels (CPOE- Computerised Physician Order Entry system).

Quickguide Doctor CPOE HistoCyto - OT.pdf

Quickguide CPOE HistoCyto - Clinic_Ward.pdf

Information entered into the CPOE system must include:

  • Patient's name, NRIC number, visit account number, age and sex
  • Hospital, department and ward number, or name of clinic
  • Clinical Diagnosis
  • Clinical summary/ procedure
  • Nature of specimen, anatomical site, and date and time specimen taken
  • Name of consultant-in-charge, doctor performing procedure and their MCR number

The following are also useful information:

  • Operative findings
  • Treatment rendered
  • Provisional diagnoses
  • Previous biopsy number or date of previous operation, if any
  • Additional tests required


Submit one electronic order for the same patient at the same operation, irrespective of the number of specimens. Make sure "Specimen Label Completed" and "Vetted & Order form completed (Dr Only)" are ticked before despatching specimens.


Additional tests ordered (immunohistochemistry, molecular, FISH or special stain), after a case has been reported, are to be accompanied by a hardcopy Histopathology request

  • Patient's name, NRIC number, visit account number, age, date of birth and sex
  • Hospital, department and ward number, or name of clinic
  • Name of consultant-in-charge, doctor performing procedure and their MCR numbers
  • Any additional important information not previously presented.


  1. Indicate date and time of sample collection on the test request.
  2. Send specimens within 24 hours of collection. If a delay is expected, refrigerate at 4oC and indicate on the test request that sample has been refrigerated.
  3. For routine tests, do not collect specimens on Saturday afternoons, Sundays and public holidays, when the Molecular Lab is closed. (Molecular lab operating hours: Mon – Fri 8.00 am to 5.00 pm, Sat 8.00 am – 1.00 pm. Closed on Sundays and public holidays)
  4. Swabs
    • Send dry Dacron swabs (i.e. no transport media). Refer to PCR/Molecular Tests for more details. Do not send laryngeal swabs.
  5. Blood
    • Blood for molecular tests must be sent in EDTA tubes, not plain blood tubes.


Send to laboratory as soon as possible within the same day of collection. Keep weekend samples in the refrigerator (2 to 8oC).

  1. Swabs
    • No dry swab.
    • Throat swab: swab back of throat and both tonsils.

    • Swab in Hanks’ virus transport medium for virus culture (with ice-pack).
    • Swab in Hanks’ virus transport medium for viral antigen + virus culture (with ice-pack).
    • Swab in sterile saline for viral antigen test.

  2. Blood
    • At least 6 mL in EDTA tube for CMV pp65 antigen (room temperature) or CMV culture (with ice -pack).
    • 5 mL in plain tube for viral antibody test (room temperature).