Detection of Peptide-Based Nanoparticles in Blood Plasma by ELISA

Aims The aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma. Materials & Methods A convenient enzyme linked immunosorbent assay (ELISA) was developed for the detection of peptides functionalized with biotin and fluorescein groups. As a proof of principle, polymerized pentafluorophenyl methacrylate nanoparticles linked to biotin-carboxyfluorescein labeled peptides were intravenously injected in Wistar rats. Serial blood plasma samples were analyzed by ELISA and by liquid chromatography mass spectrometry (LC/MS) technology. Results The ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL. We were able to accurately measure peptides bound to pentafluorophenyl methacrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS. Conclusions We detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions

Detection of peptide-based nanoparticles in blood plasma by ELISA

Aims The aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma. Materials & Methods A convenient enzyme linked immunosorbent assay (ELISA) was developed for the detection of peptides functionalized with biotin and fluorescein groups. As a proof of principle, polymerized pentafluorophenyl methacrylate nanoparticles linked to biotin-carboxyfluorescein labeled peptides were intravenously injected in Wistar rats. Serial blood plasma samples were analyzed by ELISA and by liquid chromatography mass spectrometry (LC/MS) technology. Results The ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL.We were able to accurately measure peptides bound to pentafluorophenyl methacrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS. Conclusions We detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions

Schematic representation of the nanoparticle and ELISA design.

<p>Peptide 5A contains biotin and carboxyfluorescein, lower case letters denote D-amino acids. Nanoparticles were synthesized by a free-radical polymerization method in a microemulsion system. N-isopropylacrylamide, N,N-dimethylacrylamide and acrylic acid were used as monomers with methylenebisacrylamide as cross-linker. Pentafluorophenyl methacrylate (PFM) was added and the nanoparticles were adorned with peptide 5A (B). An ELISA was designed to detect nanoparticles in biological fluids using the biotin and carboxyfluorescein groups present on peptide 5A (C). Streptavidin coated plates were used to capture the peptides by binding the biotin group and bound peptides were detected with a HRP conjugated mAb anti-fluorescein.</p

LC/MS chromatograms comparing different concentrations of peptide 5A in blood plasma matrix.

<p>Peptide 5A peaks in plasma matrix spiked with 0, 13.6 and 45.2 ng/mL (SRM trace: 877.7 → (412.2 + 341.1 + 946.4).</p

An in vitro and in vivo study of peptide-functionalized nanoparticles for brain targeting: The importance of selective blood-brain barrier uptake

Nanobiopharmaceutic