CATECHOLAMINES
For in-vitro diagnosis the kits of the serial 6xxx must be used (ELISA are available).
Namely:
| Adrenaline ELISA Fast Track | BA E-6100 |
| Noradrenaline ELISA Fast Track | BA E-6200 |
| Dopamine ELISA Fast Track | BA E-6300 |
| 2-CAT (Adrenaline /Noradrenaline) ELISA Fast Track | BA E-6500 |
| 3-CAT (Adrenaline/Noradrenaline/Dopamine) ELISA Fast Track | BA E-6600 |
The assays of the serial 6xxx for IVD-applications had been validated for plasma (EDTA) and urine samples. Any other kind of sample – including serum – have not been validated. Serum samples might be used with these kits in research applications.
This depends on the sample volume and concentration of the analyte. In most cases the research kits of the serial 5xxxR should be used. Namely:
| Adrenaline Research ELISA™ | BA E-5100R |
| Noradrenaline high sensitive ELISA | BA E-5200R |
| Dopamine high sensitive ELISA | BA E-5300R |
| 2-CAT high sensitive ELISA | BA E-5400R |
| 3-CAT high sensitive ELISA | BA E-5600R |
But in some cases, it is advantageous to use the kits of the serial BA E-6XXX. Therefore, you are advised to contact our product specialists, who have a lot of experience concerning different types of studies and protocols (support@ldn.de).
LDN recommends that tissues be homogenized in 0.01 M HCl with 1 mM EDTA and 4 mM Sodium metabisulfite. Sample dilution is dependent on expected sample concentrations. If this is unknown, we recommend a serial dilution of differing sample volumes to determine the best dilution for your particular sample type
For this procedure we offer an elaborate protocol – please inquire (support@ldn.de).
For a period up to 6 months the samples can be stored at -20 ⁰C. For the storage at -80 ⁰C we currently have no data.
If you are running the samples for IVD-purposes, you have to accomplish the assay once started without any break (in accordance with the protocol). If you are running the samples for research purposes, there is the possibility to have a break after the extraction step. For more details please contact support@ldn.de.
On a regular base we participate at the Ringversuch of INSTAND (www.instand-ev.de) for plasma and urine samples. INSTAND offers this proficiency testing every quarter.
The patient should ask his medical doctor who will give him guidelines for the collection of the sample.
No, currently we do not offer such ranges.
This was not tested yet. If you are interested in this kind of measurement, we would recommend using the high sensitive ELISA (serial BA E-5xxxR) and running a proof-of-principle. Our specialists would assist you in establishing a testing protocol (support@ldn.de).
Yes, there are automats which are capable for the automated runs of Catecholamines. For more details please contact our specialists at support@ldn.de.
If you need to dilute the samples, you can use 0.01 N HCl. The samples have to be diluted before the extraction procedure.
Our assays detect the free Adrenaline, Noradrenaline or Dopamine.
To prevent catecholamine degradation, add EDTA (final concentration 1 mM) and sodium metabisulfite (final concentration 4 mM) to the sample as early as possible.
A pH > 7.0 during the extraction is mandatory.
SEROTONIN
The most common sample matrix used for IVD is serum. The Serotonin ELISA Fast Track (BA E-8900) was validated for serum. In general, plasma is not recommended for testing of Serotonin, as the thrombocytes might undergo lysis and release their high content of Serotonin. As the degree of lysis is very different and varying from sample to sample, it will interfere with the measurement in an unpredictable way.
Yes.
For platelet-rich plasma the Serotonin ELISA Fast Track (BA E-8900) can be used as an IVD-application. For the RUO-determination of Serotonin in platelet-poor plasma and CSF the high sensitive ELISA BA E-5900R has to be used.
This was not tested yet. If you are interested in this kind of measurement, we would recommend using the Serotonin high sensitive ELISA (BA E-5900R) and running a proof-of-principle. Our specialists would assist you in establishing a testing protocol (support@ldn.de).
Yes, on a regular base INSTAND (www.instand-ev.de) offers Ringversuch for urine and plasma samples. INSTAND offers this proficiency testing every quarter.
Yes, there are automats which are capable for the automated determination of Serotonin. For more details, please contact our specialists at support@ldn.de.
For homogenates and cell culture samples the Serotonin high sensitive ELISA (BA E-5900R) is recommended. Special attention has to be paid to the pH as Serotonin is not stable in acidic milieu (the use of a stabilizer is mandatory). The use of cold buffers is mandatory and the samples should not be stored too long under acidic conditions.
Our general advise for the preparation of tissues is homogenisation in 0.01 N HCl + 1 mM EDTA + 4 mM sodium metabisulfite. Homogenise, spin down and use the clear supernatant for the assay. The ratio tissue to HCl depends on the expected concentrations and also the sample volume that should be extracted depends on expected concentrations. If this is unknown then it is best to use relatively low HCl volumes and extract different sample volumes.
For different animal serum samples – such as mouse or rat samples – the Serotonin Fast Track ELISA (BA E-8900) might be an alternative. Our specialists do have a lot of experience with different kinds of Serotonin studies, and they will assist you in establishing your specific testing protocol (support@ldn.de).
HISTAMINE and HISTAMINE RELEASE
No, currently we do not offer such ranges.
Yes, there are automats which are capable for the automated determination of Histamine. For more details please contact our specialists at support@ldn.de
For the Release, heparin is recommended as less basophile cells are destroyed.
No, because too many cells are destroyed which will give a high background.
For the measurement of Histamine in different animal plasma samples, the Histamine high sensitive ELISA (BA E-5800R) is recommended. The following chart shows some examples of Histamine concentrations measured in different animals:
Animal species | Concentration (ng/ml) |
Mouse | 22.9 |
Rat | 20 |
Cat | 1.1 |
Dog | 0.3 |
Horse | 0.6 |
GABA (Gamma-aminobutyric acid) and GLUTAMATE
In general, there will be many different buffers which can be used for preparing the cell lysates and which will not interfere with our assay. To be sure that the buffer is compatible with the assay, we always advise to perform a proof of principle. You could spike your buffer with GABA and measure the recovery. You could use the highest standard provided in the kit for spiking.
An excess of acid should be avoided: For GABA, a pH of 3.0 during the extraction procedure of the assay is mandatory, for Glutamate a pH of 5.0.
Our general advise for the preparation of tissues is homogenisation in 0.01 N HCl + 1 mM EDTA + 4 mM sodium metabisulfite. Homogenise, spin down and use the clear supernatant for the assay. The ratio tissue to HCl depends on the expected concentrations and also the sample volume that should be extracted depends on expected concentrations. If this is unknown, then it is best to use relatively low HCl volumes and extract different sample volumes.
TRYPTOPHAN
The precipitation procedure releases the bound fraction in the sample so that the assay detects the total Tryptophan.
Yes, the kit can be used for various biological samples. For more details, please contact our specialists at support@ldn.de.
METANEPHRINES IN URINE
No, we do not have these ranges.
FREE METANEPHRINES IN PLASMA
In case of a result in the grey area, it is recommended to collect a new sample together with an anamnesis concerning especially influences like the medication and age of the patient.
Using our kit, we recommend collecting the blood sample with the patient in an upright/sitting position.
No, serum samples are not recommended – one must use EDTA- or Heparin plasma.
Yes, there are automats which are capable for the automated determination of these Metanephrines. For more details, please contact our specialists at support@ldn.de.
In principle, it is possible to measure the Metanephrines in different animal species. For more details, please contact our specialists at support@ldn.de.
Sympathomimetic agents, sport and smoking can also influence Metanephrine and Normetanephrine level. Alcohol and caffeinated drinks should be avoided the day before and including the day of sample collection.
5-HIAA (5-Hydroxy-3-Indole Acetic Acid)
There is the possibility to run an extraction procedure with such samples for research applications. For more details, please contact our specialists at support@ldn.de.
CHROMOGRANIN A
Medications like proton pump inhibitors, selective serotonin reuptake inhibitors and histamine type-2 receptor antagonists can influence CgA level in serum. People who are taking such medication should consult with their doctor before specimen collection.
On a regular base we participate at the Ringversuch of RfB (https://www.rfb.bio ). RfB offers this proficiency testing every quarter.
The assay was validated for serum samples and serum must be used when running samples for IVD-purposes. But for research applications, plasma might also be a suitable sample matrix.
FOOD SAFETY
Yes, LDN participates on a regular base at the external quality assessment scheme of FAPAS. The participating assay is the HistaSure ELISA Fast Track (FC E-3600).
Results are available upon request (support@ldn.de) .
For these applications, the HistaSure ELISA Fast Track (FC E-3600) had been tested and is recommended. For more details, please contact our specialists at support@ldn.de .
If not tested immediately, the extracted samples can be stored frozen at -20 ⁰C.
No, we do not offer such a program. But there are good and reliable online calculation programs for free which can be used, such as Myassays.com.
Yes, for running an assay on ELISA processors, we recommend the HistaSure ELISA Fast Track (FC E-3600). For example, this assay can easily be adapted on the Gemini and other automats identical in construction.
HISTAMINE FOOD ELISA
The histamine concentration read from the standard curve is not the final concentration – but has to be multiplied with the corresponding dilution factor used for the sample preparation. In the IFU, the dilution factors for the most frequently kinds of samples preparations (fish, sausage, cheese, milk, wine and champagne are listed).
HistaSure ELISA Fast Track
All fish samples tested so far are suitable for the HistaSure ™ ELISA Fast Track. The lists below depict some major applications in different matrices.
Species validated through AOAC Certification | Fish species | Presentation |
Tuna | canned chunk light | |
fresh/frozen yellow fin | ||
Mahi Mahi | fresh/frozen | |
Sardines | canned in oil | |
Fishmeal |
Species validated through in-house testing | Fish species | Presentation |
Mackerel | smoked | |
Anchovy | fresh | |
brined | ||
in sauce | ||
Shad | dry salted | |
fermented | ||
Herring | smoked | |
Salmon | smoked | |
Bonito | lakerda | |
Swordfish | fresh | |
Marlin | fresh |
Fish products validated through in-house testing | Maldive fish |
Fish sauce (sardines/anchovy) | |
Oyster sauce (oyster/sardines) |
Please contact us (support@ldn.de) if you cannot find your sample of interest in this list – we will check your application.
No, if you have prepared an uniform homogenate you can just take a small aliquot of a few ml for the filtration/centrifugation.
No, the use of a shaker is mandatory.
Yes, the following controls are available upon request:
- 0 ppm (FC C-0051)
- 50 ppm (FC C-0052)
- 100 ppm (FC C-0053)