Adsorption of Cationic Peptides to Solid Surfaces of Glass and Plastic

Abstract

Cationic membrane-active peptides have been studied for years in the hope of developing them into novel types of therapeutics. In this article, we investigate an effect that might have significant experimental implications for investigators who wish to study these peptides, namely, that the peptides adsorb to solid surfaces of glass and plastic. Specifically, we use analytical HPLC to systematically quantify the adsorption of the three cationic membrane-active peptides mastoparan X, melittin, and magainin 2 to the walls of commonly used glass and plastic sample containers. Our results show that, at typical experimental peptide concentrations, 90% or more of the peptides might be lost from solution due to rapid adsorption to the walls of the sample containers. Thus, our results emphasize that investigators should always keep these adsorption effects in mind when designing and interpreting experiments on cationic membrane-active peptides. We conclude the article by discussing different strategies for reducing the experimental impact of these adsorption effects.

Prolonged immunomodulation in inflammatory arthritis using the selective Kv1.3 channel blocker HsTX1[R14A] and its PEGylated analog

“…Peptides such as HsTX1 and its analogs are known to adsorb onto surfaces, such as the polystyrene in the microplates used in proliferation assays. PEGylation has been proposed as a means for reducing peptide and protein adsorption onto surfaces [55; 56; 57; 58]. We therefore assayed the recovery of HsTX1[R14A] and PEG-HsTX1[R14A] after a 24 h incubation in the microplates used for our proliferation assays and, indeed, we observed a much lower recovery of HsTX1[R14A] than of its PEGylated analog.…”

“…In contrast, both peptides inhibited the proliferation of human and rat T EM cells with similar potencies. Toxin-derived peptides are prone to adsorption onto plastics, such as polystyrene in tissue culture microplates, and PEGylation of peptides and proteins can significantly reduce their adsorption [55; 56; 57; 58]. We therefore tested whether a 24-h incubation of HsTX1[R14A] or PEG-HsTX1[R14A] at room temperature in a tissue culture microplate affected peptide recovery, assessed by its ability to block Kv1.3 channels.…”

Cationic bactericidal peptide 1018 does not specifically target the stringent response alarmone (p)ppGpp

“…Effects on biofilms were studied on glass in flow cell chambers under conditions of constant medium flow10. This would allow for the sorption and accumulation of the peptides on the cell surface over time, and surface-specific sorption is a well-known property of cationic peptides21. The MIC was determined using a broth microdilution method, which does not involve a continuous flow of liquid and is performed with 96-well plates or Eppendorf tubes made of laboratory plastic22.…”

Quantitative determination of human IgA subclasses and their Fc‐glycosylation patterns in plasma by using a peptide analogue internal standard and ultra‐high‐performance liquid chromatography/triple quadrupole mass spectrometry

“…We therefore added digested BSA (50 μg) to samples and compared the intensities of the K1 internal standard with those of samples without digested BSA. It is also reported that Protein LoBind tubes (LB) could increase the recovery of proteins by decreasing protein adsorption to the tube wall . We also compared the performance of using Protein LoBind tubes in this study.…”