Probing label-free intracellular quantification of free peptide by MALDI-ToF mass spectrometry.
Methods
; 68(2): 331-7, 2014 Jul 01.
Article
em En
| MEDLINE
| ID: mdl-24657280
ABSTRACT
Cell-penetrating peptides are promising reagents for gene and drug delivery. They can efficiently traverse the plasma membrane and deliver various cargo materials ranging from genes to nanoparticles. The functional efficiency of cargo often depends on the completeness of intracellular peptide uptake, which can be measured, but its quantification remains largely inconclusive. Existing approaches rely on the use of radioactive and fluorescent labels or tags which allow colorimetric, fluorescent or spectrometric detection, but lack the ability to detect free peptide. Herein we describe a generic label- and tag-free method to measure the concentration of internalised peptide by matrix-assisted laser desorption/ionisation time of flight mass spectrometry. Quantification is preceded by two-dimensional chromatography and is performed at benign temperatures for the lysates of human dermal fibroblasts transfected with cell penetrating peptides in free form. Isotopically labelled peptides of the same structure are used as internal standards to enable accurate determination of concentration of the recovered free peptide. The method offers a minimalistic approach for intracellular quantification, which can be used as a correlative measure for fluorescence-based imaging methods.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sistemas de Liberação de Medicamentos
/
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
/
Nanopartículas
/
Peptídeos Penetradores de Células
Limite:
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article