Porex Technologies, the manufacturer of the FILTER SAMPLER® BLOOD SERUM FILTER and DISPENSE Serum Filter, routinely tests these products for their use in various chemistry, coagulation, and drug monitoring methodologies. Our clinical compatibility tests are conducted at large reference laboratories located in Atlanta, GA, USA. 

A thorough review of all of our material and processes has determined that the FILTER SAMPLER® BLOOD SERUM FILTER and above products do not contain the chemical TRIBUTOXETHYLPHOSPHATE. This chemical is not present in any of the components of the product, nor do we use this chemical during our process. It is our understanding that this chemical can cause interference with drug methodologies. 

Studies included testing the SERUM FILTER components and assembled products in contact with serum or plasma on 22 common biochemical constituents as well as T3 UPTAKE and T4 RIA. Samples are tested after 8 hours, 24 hours, 3 days, 4 days and 7 days of contact with these products. The constituents are as follows: 

  • Total Protein
  • Cholesterol
  • Sodium  
  • Albumin
  • Glucose
  • Potassium  
  • Triglycerides
  • Chloride
  • BUN  
  • Total Bilirubin
  • Creatinine
  • CO2  
  • Alkaline Phosphotase
  • SGOT
  • Iron  
  • Calcium
  • LDH
  • CPK 
  •  Phosphorous
  • T4 RIA

No patterns of interference were noted with the IB™ Model FILTER SAMPLER or DISPENSE FILTER SAMPLER®, set with the ion-barrier feature, for up to seven days.

Also, as part of our quality control process we have tested the serum filters for their use and non-interference with analytical determinations using gas liquid chromatography (GC) and high performance liquid chromatography (HPLC). The methodologies tested were: 

  • Valporic Acid
  • Digoxin  
  • Theophylin
  • Lithium

No patterns of interference peaks were noted on the above constituents after three days.  

With coagulation methodologies tests were performed using normal population and capped specimens.  

In terms of coagulation, plasma may be separated with the I.B.™ Model and once properly refrigerated and capped, storage is permitted with no methodology interference for up to four days. The I.B.™ Model contains a leakproof valve that allows the creation of a half-inch air gap, which prevents the transfer of potassium and phosphate ions that cause pH changes and specimen unsuitably past the recommended storage times without the use of the I.B.™ Model Serum Filter.  

Methodologies tests for compatibility with the IB™ Model or the Dispense FILTER SAMPLER®, set with the ion-barrier feature, up to four days are:

  • Prothrombin Time (PT)  
  • Activated Partial Thromboplastin Time (APTT)  
  • Partial Thromboplastin Time (PTT)  
  • Fibrinogen