Product Summaries

Our Kits in Animal Research

Monday, 06 July 2009 17:00

Below is a chart that identifies which parameters we have tested using our own kits. Note that we do not specify which kit, because as changes are made to the kits over time, the basic principles continue to hold true for all our kits.

Important: each laboratory should evaluate the protocol according to official guidelines (e.g. GLP, etc.).

The following contains a chart with the documented cross-reactivities of our kits. Although we are permanentely updating this chart we would kindly ask you to contact our product specialists to discuss your special project.

Last Updated on Monday, 01 February 2010 11:03

Histamine Intolerance

Wednesday, 17 June 2009 13:27

Is it an allergy or Histamine intolerance?

With our Histamine in Stool ELISA, there is a novel way to tell the difference between what could be a result of histamine intolerance or an allergic reaction to food.

Assay Characteristics:

Quantitative results in less than 2 hours
Unique sampling and shipping device
Samples stable for 1 week at 37°C

View Product Details

Last Updated on Friday, 12 February 2010 08:49

Serotonin Assays -From The Serotonin Experts

Monday, 04 February 2008 16:47

The most comprehensive and innovative serotonin panel available- only from LDN

The evolution of our serotonin kits continue their path to better meet the needs of our customers. Whatever sample you're targeting, we have the optimal solution:

Our unique CE-labeled RIA (BA R-8900) and innovative ELISA (BA E-8900) test kits may be used to determine Serotonin in serum, platelet-rich plasma (PRP), platelet-poor plasma (PPP), CSF, urine, cell cultures and tissue homogenates.

Our exclusive Serotonin Research RIA™ (BA E-8900) and Serotonin Research ELISA™ (BA-E-5900) test kits are of highest sensitivity, and therefore, the ideal tool for scientists breaking new grounds.

LDN as a team has decades of experience in the arena of serotonin testing. If you are looking for a customized solution to your testing needs, then you rely on us as an accomplished partner.

Last Updated on Friday, 22 January 2010 10:52

Urinary Metanephrines

Tuesday, 26 December 2006 16:47

Background Information

Metanephrine (metadrenaline) and normetanephrine (normetadrenaline) are physiological breakdown products of the catecholamines adrenaline and noradrenaline, which play an important role as hormones and neurotransmitters. Metanephrine and normetanephrine are excreted in urine or broken down further in the body to the end product of catecholamine metabolism vanilylmandelic acid.

The diseases which are associated with an increased concentration of metanephrine and normetanephrine are catecholamine-producing tumors, for example, neuroblastoma, ganglioneuroma, and phaeochromocytoma. Of these, phaeochromocytoma has the greatest significance. Phaeochromocytomas are excessively catecholamine-secreting tumors, which originate in the adrenal medula and can, in combination with operative procedures and anaesthesia, lead to life-threatening situations. Around 10% of all phaeochromocytomas show malignant growth. In most cases, however, they can be cured by operative therapy combined with medication therapy using ?-adrenergen antagonists. An unidentified phaeochromocytoma, on the other hand, poses a serious risk to the patient.

The determination of metanephrine and normetanephrine (or catecholamine) concentrations is therefore essential in patients with suspected phaeochromocytoma. These tests are also frequently used in the initial diagnosis of hypertonia.

RIA- The assay kit provides materials for the quantitative measurement of normetanephrine and metanephrine in urine. During the sample preparation normetanephrine and metanephrine are quantitatively acylated to their corresponding N-acyl-derivates. The assay procedure follows the basic principle of radioimmunoassays, involving competition between a radioactive and a non-radioactive antigen for a fixed number of antibody binding sites. The amount of 125I-labeled antigen bound to the antibody is inversely proportional to the analyte concentration of the sample. When the system is in equilibrium, the antibody bound radioactivity is precipitated with a second antibody in the presence of polyethylene glycol. The precipitate is counted in a gamma counter. Quantification of unknown samples is achieved by comparing their activity with a reference curve prepared with known standards.

ELISA- The competitive EIA kit uses the microtiter plate format. Metanephrine and normetanephrine, respectively, are bound to the solid phase of the microtiter plate. The acylated metanephrine and normetanephrine from the sample and solid phase bound nephrines compete for a fixed number of antiserum binding sites. When the system is in equilibrium, free antigen and free antigen-antiserum complexes are removed by washing. The antibody bound to the solid phase metanephrine and normetanephrine is detected by an anti-rabbit IgG-peroxidase conjugate using TMB as a substrate. The reaction is monitored at 450 nm with the amount of antibody bound to the solid phase nephrine being inversely proportional to the nephrine concentration of the sample.

ELISA vs. HPLC Comparison- Urine

The metanephrine and the normetanephrine concentrations in 27 urine samples were assessed using both the LDN EIA (x) and the HPLC method (y) (external QC samples from UK NEQAS). The UK control values are the mean of about 40 different HPLC users, and contain always one pathological sample per sending. The results of linear regression analysis showed the following correlation characteristics: y=0.88x - 0.10, r=0.99 for metanephrine and y=1.09x + 0.3, r=0.99 for normetanephrine.

Bottom Line: The LDN ELISA is comparable to the HPLC method

RIA vs. HPLC Comparison- Urine

The metanephrine and the normetanephrine concentrations in 21 urine samples were assessed using both the LDN RIA (x) and the HPLC method (y) (external QC samples from UK NEQAS). Therefore the correlation between RIA and HPLC is excellent. UK control values are the mean of about 40 different HPLC users, and contain always one pathological sample per sending. The results of linear regression analysis showed the following correlation characteristics for metanephrine: y=1.01x – 0.09, r=0.99, and for normetanephrine y=0.95x + 0.17, r=0.99

Bottom Line: The LDN RIA is comparable to the HPLC method

Advantages of LDN Metanephrine Kits

Customer Service! - We use the kits we sell, and we always offer a 24 hour turn around on almost all technical questions.
Freedom from drug Interference!
Complicated HPLC and LC/MS procedures can now be overcome with easy to use ELISA’s and RIA’s
Excellent correlation with other methodologies.
QUALITY- Produced according to ISO:13485

Last Updated on Wednesday, 10 February 2010 11:53

Catecholamine ELISA and RIA Immunoassays

Tuesday, 07 November 2006 16:08

Introduction

Adrenaline (epinephrine) and noradrenaline (norepinephrine) together with dopamine constitute the group of catecholamines, which play an important role as hormones and neurotransmitters. Catecholamines are biogenic amines which are synthesized from the amino acid tyrosine via the intermediate product dopa.

Last Updated on Wednesday, 10 February 2010 09:53