55000 Amino Acids and Acylcarnitines from Dried Blood

MassChrom® Amino Acids and Acylcarnitines from Dried Blood - LC-MS/MS

Order no.: 55000
960 Tests
  • Acylcarnitines & free carnitine
  • Amino acids

Sample prep with derivatisation of the analytes
With 96 well plates

Description

Clinical relevance

Newborn screening aims to detect congenital metabolic disorders early on before they can cause harm to the organism. Included in these diseases are defects of amino acid metabolism such as phenylketonuria (PKU) and maple syrup urine disease (MSUD), defects of fatty acid metabolism and organic acidurias (isovaleric acidemia). If these diseases are not diagnosed, the metabolic disorders can already lead to severe irreversible harm to the newborns within their first few days of life.

Mass spectrometry is the method of choice for diagnostic testing: it enables to check for a broad range of metabolic defects in a single run. An HPLC column is not required due to the high selectivity of LC-MS/MS. This makes it possible to achieve a very precise quantification in a very short analysis time of less than 2 minutes.

 

Product advantages

  • Simple SUAC determination with upgrade set
  • Screening for many metabolic disorders in a single run such as PKU (Phenylketonuria), MSUD (Maple Syrup Urine Disease) and tyrosinemia type I
  • Each analyte safeguarded by its own internal standard

 

This Chromsystems assay allows the fast and reliable determination of amino acids, acylcarnitines and succinylacetone from dried blood spot samples as part of the newborn screening for amino acid and fatty acid metabolic disorders using tandem mass spectrometry. Sample preparation is based on effective extraction of the analytes from the blood spot with subsequent derivatisation. The use of stable isotope labelled internal standards for calibration and measurement ensures reliable and precise quantification of the analytes.

For the analysis of succinylacetone an upgrade set is available (order no. 55111).

Here's an overview of all our newborn screening assays.

Technical Data

Method of Analysis

LC-MS/MS

Number of Tests

960

Parameter

Acylcarnitines & free carnitine, Amino acids

Analysis Time

< 2 min

Limit of quantification

Amino acids with SUAC: 0.5-5 µmol/l
(Acyl-)carnitines: 0.05-0.5 µmol/l

Linearity

Amino acids with SUAC: 250-2500 µmol/l
(Acyl-)carnitines: 11-240 µmol/l

Recovery

Amino acids with SUAC: 51-94 %; (Acyl-)carnitines: 62-89 %

Intraassay

Amino acids with SUAC: CV = 4-10 %
(Acyl-)carnitines: CV = 4-20 %

Interassay

Amino acids with SUAC: CV = 5-9 %
(Acyl-)carnitines: CV = 8-28 %

Cutoff thresholds

Amino acids 22-743 µmol/l
Free carnitine 50-60 µmol/l
Acylcarnitines 0.1-48 µmol/l
SUAC 1.16 µmol/l

Information

Mass transitions of analytes and internal standards

Amino acids Neutral Loss Scan 102
Alanine 146 > 44
Alanine-D4 150 > 48
Aspartic acid 246 > 144
Aspartic acid-D3 249 > 147
Glutamic acid 260 > 158
Glutamic acid-D5 265 > 163
Leucine 188 > 86
Leucine-D3 191 > 89
Methionine 206 > 104
Methionine-D3 209 > 107
Phenylalanine 222 > 120
Phenylalanine-D5 227 > 125
Tyrosine 238 > 136
Tyrosine-D4 242 > 140
Valine 174 > 72
Valine-D8 182 > 80
Amino acids and SUAC MRM
Arginine 231>70
Arginine-D7 238 > 77
Citrulline 232 > 113
Citrulline-D2 234 > 115
Glycine 132 > 76
Glycine-13C2-15N 135 > 79
Ornithine 189 > 70
Ornithine-D6 195 > 76
Proline 172 > 116
Proline-D7 179 > 123
SUAC 211 > 109
SUAC-13C5 216 > 114
Acylcarnitines and free carnitine Parent Ion Scan 85
Carnitine 218 > 85
Carnitine-D9 227 > 85
C2-Carnitine 260 > 85
C2-Carnitine-D3 263 > 85
C3-Carnitine 274 > 85
C3-Carnitine-D3 277 > 85
C4-Carnitine 288 > 85
C4-Carnitine-D3 291 > 85
C5-Carnitine 302 > 85
C5-Carnitine-D9 311 > 85
C5DC-Carnitine 388 > 85
C5DC-Carnitine-D6 394 > 85
C6-Carnitine 316 > 85
C6-Carnitine-D3 319 > 85
C8-Carnitine 344 > 85
C8-Carnitine-D3 347 > 85
C10-Carnitine 372 > 85
C10-Carnitine-D3 375 > 85
C12-Carnitine 400 > 85
C12-Carnitine-D3 403 > 85
C14-Carnitine 428 > 85
C14-Carnitine-D3 431 > 85
C16-Carnitine 456 > 85
C16-Carnitine-D3 459 > 85
C18-Carnitine 484 > 85
C18-Carnitine-D3 487 > 85

Flow rate

20–600 µl/min

Specimen

Dried blood

Pre-analytic Treatment

Specimen collection: whole blood from the heel of the newborn taken onto a filter card. Collection between 24th and 72nd hour of life depending on individual national guideline.

Stability: storage at low humidity (< 30 %) and ambient temperature is sufficient if analysis is performed within 24 to 48 hours. For longer storage deep-freeze samples with humidity excluded below -18 °C.

Sample Preparation

  • Punch out 3.2 mm blood spots from the filter cards into a 96 Well Plate.
  • Add 200 μl Internal Standard and agitate for 20 min.
  • Transfer supernatant into a new 96 Well Plate (or with 55000/F centrifuge for 2 min).
  • Evaporate supernatant.
  • Add 60 μl Derivatisation Reagent and incubate for 15 min at 60 °C.
  • Evaporate to dryness.
  • Add 100 μl Reconstitution Buffer and agitate for 1 min.
  • Inject 10 μl into the LC-MS/MS system.

 

In the sample preparation for the analysis of succinylacetone the following additional steps have to be performed before derivatisation: Add Internal Standard, agitate 30 min, combine extracts (pipette).

For details please refer to the instruction manual.

Injection Volume

10 µl

Autosampler rinsing solution

Rinsing Solution (55007)

MS/MS-Mode

Amino acids: MRM / Neutral Loss Scan of 102 (m/z); Acylcarnitines: Parent Ion Scan of 85 (m/z)

Additional Info

No HPLC column is required.

Please note

The freely available information on this website, in particular on the sample preparation, are not sufficient to work with our products. Please read instructions and warning notices on products and/or instruction manuals.

Kit Components

Controls