Specimen Collection and Supplies

Medical Assay Laboratory will provide physician offices and nursing homes with specimen collection supplies and containers at no cost.   We will provide blood collection tubes and urine tubes, needles, needles holders, foam pack, and containers for proper disposal of used needles.   At Medical Assay Laboratory, we believe that the quality of specimens is strongly correlated with quality results.  Therefore, we require careful specimen collection and tagging.  Each specimen should have the patient’s name, date and time of collection, and specimen type.

Requisition.  We require that specimen(s) be accompanied by a requisition.  Each requisition should contain the patient name, age, sex, date specimen was drawn, test requested, and patient billing information.


Blood Collection Tubes

Regular Red Top:  Contains no anticoagulant or preservative.  Use for serum yield only.  Allow sample to clot for 20 minutes in an upright position.  Centrifuge for 10 minutes and transfer serum to a properly labeled pour-off tube.

Lavender Top:  This tube contains EDTA anticoagulant specially designed for most hematological procedures. It is necessary to fill the tube to its capacity so that the ratio of anticoagulant to blood is proper. Mix the sample by gently inverting the tube at least 6-8 times to facilitate mixing of the blood anticoagulant.  Do not centrifuge

Gray Top:  This tube contains oxalate as an anticoagulant and flouride as a preservative. After the tube has been filled with blood, it should be inverted at least 6 times in order to facilitate mixing and prevent coagulation.  Do not centrifuge.

Light Blue Top:  This tube contains a citrate solution which is specific for Prothromin Time Testing (PTT). It is imperative that a minimum of 4.5 ml blood be drawn into this tube. The vacuum contained in this tube should draw that amount. The ratio of blood to anticoagulant is critical for valid PTT results. This tube should be inverted at least 6 times in order to facilitate mixing and prevent coagulation. Centrifuge for a minimum of 15 minutes and transfer plasma to a labeled plastic pour-off tube.  Freeze immediately and be sure that sample arrived frozen and within 24 hours.

Royal Blue:  This may contain sodium heparin for trace metal studies of whole blood.  Mix sample by gentle inversion 6-8 times.  Do not centrifuge.

Green Top:  This tube contains Heparin anticoagulant. Certain specific hematological (chromosomal) analyses demand this anticoagulant. After the tube has been filled with blood, invert gently at least 6 times to facilitate mixing and prevent coagulation.


Red/Gray Top:  This tube contains a special gel with no preservative or anticoagulant added. The purpose of this tube is to be proper receptacle for clotted blood and subsequent serum specimen. Draw the blood to the full capacity of the tube. For those tests which list in the specimen type column, "Serum", the serum must be separated from the cells within forty-five minutes of venipuncture. Many test findings are invalid if the serum remains in contact with the cellular elements for more than forty-five minutes. Serum may be separated from the cells by centrifugation. Medical Assay Laboratory will provide centrifuges for those physicians requesting them.

Yellow Top (7 ml).   This tube contains ACD solution and is to be used only for Blood Group and Type. Tubes are clearly marked.

Yellow Top (10 ml).  This tube is to be used for blood culture.

Clear Plastic:   This vial has been specifically designed to contain the serum which has been withdrawn from the Red Top Tube after centrifugation. Snap the cap securely for transport to the laboratory, with proper patient name affixed.

Urinalysis Vial:  Plastic vial with graduated measurement indicator and orange or yellow cap.  Preservative in tablet form added.



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