Specimen Preparation. Serum: Dilute serum samples 1:2 with 0.85% saline solution (1 part serum and 1 part 0.85% saline solution). Urine: Urine samples may be run neat, diluted or concentrated. One application or three applications can be made to obtain desired intensity. To concentrate urine, shake samples to homogenize. Centrifuge desired volume at 2000 x g for 5 minutes. Remove supernatant and concentrate as follows: Total Protein (mg/dL) Conc. Factor < 50 100x 00-000 00x 000-000 00x 000-000 00x > 600 5x CSF: CSF samples may be used after proper concentration of 10-50x. Materials provided: The following materials needed for the procedure are contained in the SPIFE SPE Hi Res-20 Kit (Cat. No. 3430). Individual items are not available. SPIFE SPE Hi Res-20 Gels (10) Acid Violet Stain (1 vial) REP Blotter C (10) Citric Acid Destain (1 pkg) Blade Applicator Kit (10) Materials provided by Helena Laboratories but not contained in the kit: SPIFE 3000 Analyzer 1088 Hi Res Protein Marker 5141 Gel Block Remover 1115 REP Prep 3100 Applicator Blade Weights 3387 Disposable Sample Cups 3369 SPIFE Dispo Cup Tray 3370 Materials needed but not provided: 10% Acetic Acid 0.85% Saline Solution I. Sample Preparation
Specimen Preparation. The shipping test unit (product and package) should be mechanically, cosmetically and functionally representative of final production units. For testing purposes, the packaging may be without labeling requirements.
Specimen Preparation. Prepare platelet rich plasma (PRP) by centrifuging both of the anticoagulated samples at 100 x g 10-15 minutes at room temperature. DO NOT BRAKE THE CENTRIFUGE. Remove the PRP from the cells with a plastic pipette and place in a plastic tube labeled PRP. Cap the tube and maintain at room temperature. Wait 30 minutes after PRP is removed before testing.
Specimen Preparation. Centrifuge the whole blood specimen at an appropriate rcf and length of time to obtain a platelet poor plasma. Specimens may be spun twice, if time permits. Immediately separate the plasma from the red blood cells and place it in a plastic test tube with cap. Storage and Stability: Perform the activated partial thromboplastin time assay within 2 hours. Do not allow specimen to stand at 37°C for more than 5 minutes. The plasma sample should be stored in capped plastic test tubes at 2 to 8°C. If testing is delayed for more than 2 hours, plasma may be stored at -20°C or colder for up to one month. Thaw quickly at 37°C prior to testing but do not allow to stand at 37°C for more than 5 minutes. Interfering Substances: Erroneous results may be caused by contamination with tissue fluids or stasis. Avoid agitation, air bubbles or foaming. For the effects of commonly administered drugs, refer to Young, et al.6
Specimen Preparation. The important requirements in specimen preparation are the quality of the two contact surfaces and the accuracy of the thickness. A small excess for each contact surface should be left during the initial machining, and the two surfaces should then be carefully ground to the final thickness to remove any machining marks and to eliminate the residual stresses and surface damage which might have been caused by the initial machining. Any final polishing of the specimen is typically carried out using FEPA P120 (ANSI #120 grit) followed by FEPA P500 (ANSI #320 grit) sandpaper. It is considered that the surface finish of the specimen is less critical than that the top and bottom surfaces of the specimen are parallel. During polishing, therefore, the specimen thickness should be checked at multiple points on the surface to ensure that the surfaces are parallel within +/- 0.01mm. The specimen should have an arithmetic mean roughness Ra value of maximum 0.30µm or 12 micro-inch.
