Some chemical, physical and biologic characteristics of dyes used to visualize lymphatics

¹ Department of Medicine, Tulane University School of Medicine; and Research Laboratory, Touro Infirmary, New Orleans, Louisiana

Characteristics of dyes used to study lymphatics and other biologic systems can be of significance in quantification and interpretation of data. For example, determination of concentration is influenced by changes in spectral characteristics of solutions of Patent Blue V (PBV), T-1824 or Direct Sky Blue (DSB) produced by changes in pH. Interpretation of biologic data must consider the 50% binding of PBV and the almost 100% binding of T-1824 and DSB demonstrated by protein precipitation studies. This was confirmed for PBV by dialysis, but not for T-1824 or DSB because they adhered to the viscose bag as they did to the filter paper during attempts at electrophoresis. PBV moved independently of protein on electrophoresis, suggesting a weak linkage. After intradermal injection, all three dyes first visualized, then diffused from lymphatics. Only PBV appeared in urine in measurable quantities, approximately 10% being recovered in urine before it was too dilute to measure in 24 hours. One-half that excreted was recovered in the first 2 hours.