Highly sensitive and selective separation of intact parathyroid hormone and variants by sheathless CE-ESI-MS/MS.
Electrophoresis
; 40(11): 1550-1557, 2019 06.
Article
en En
| MEDLINE
| ID: mdl-30815902
Parathyroid hormone (PTH) is a common clinical marker whose quantification relies on immunoassays, giving variable results as batch, brand, or target epitope changes. Sheathless CE-ESI-MS, combining CE resolution power and low-flow ESI sensitivity, was applied to the analysis of PTH in its native conformation in the presence of related forms. Fused silica and neutral-coated capillaries were investigated, as well as preconcentration methods such as transient isotachophoresis, field-amplified sample injection (FASI), and electrokinetic supercharging (EKS). The method for the separation of PTH and its variants was first developed using fused-silica capillary with UV detection. An acidic BGE was used to separate 1-84 PTH (full length), 7-84 PTH, and 1-34 PTH. Acetonitrile was added to the BGE to reduce peptide adsorption onto the capillary wall and transient isotachophoresis was used as analyte preconcentration method. The method was then transferred to a sheathless CE-ESI-MS instrument. When using a fused silica capillary, CE-MS was limited to µg/mL levels. The use of a neutral coating combined with FASI or EKS allowed a significant increase in sensitivity. Under these conditions, 1-84 PTH, 7-84 PTH, and 1-34 PTH were detected at concentrations in the low ng/mL (FASI) or pg/mL (EKS) range.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Hormona Paratiroidea
/
Fragmentos de Péptidos
/
Electroforesis Capilar
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
Electrophoresis
Año:
2019
Tipo del documento:
Article
País de afiliación:
Bélgica