Introduction:

Polybrene^®, a positively charged polymer,¹ is a wellknown anti-heparin agent.^2-4 It is also a useful diagnostic tool in the selective functional studies of the anterior pituitary and zona glomerulosa of the adrenal cortex.^5-8 Polybrene^® produces a nonspecific agglutination of red blood cells,^1,9 attributed to neutralization of the net negative charge of the red blood cells.⁹ A sensitive, automated technique for the detection of antibodies using Polybrene^® has been developed. This “Automated Polybrene^® Technique” involves a three-phase procedure:^1,11

1. Rapid sensitization of the test red blood cells by antibodies in an acidified low ionic medium
2. Agglutination of the red blood cells by treatment with Polybrene^®.
3. Reversal of the Polybrene^® effect with an isotonic salt solution, i.e., the repelling forces on the red blood cells are restored, thus effecting their deaggregation and resuspension.

Detection and determination of antibodies are based on the temperature-dependent deaggregation phase in which any remaining red cell aggregates are hemolyzed and the hemoglobin measured colorimetrically. The method affords a very useful clinical and blood-banking tool.

The “Automated Polybrene^® Technique” has been used to study acquired hemolytic anemia¹⁰ and the thermal properties of antigen-anti body complexes.¹¹

The coagulant property of Polybrene^® has been utilized in developing an accurate, rapid and simple method for the assay of heparin activity in vitro.¹² Polybrene^® is the specific neutralizing agent. This test is a simplification of the conventional “thrombin time.”

Polybrene^® has also been used to enhance virus detection in the MuLV and MSV systems in vitro.¹³

Polybrene^® has been found to greatly enhance the degradation of peptides on automated sequential analysis.^14,15

The cationic polymer is also used in formulating hairconditioning, skin-moisturizing, and skin-softening agents.¹⁶