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Ad-A-Gene — Compatible Instrumentation for EGFP/eFP vectors

Q: What instrumentation is suitable for viewing Ad-A-Gene EGFP or eFP assay results? A. Cells transduced by Ad-A-Gene adenoviral vectors encoding EGFP or eFP fusion proteins can be imaged on ...

Ad-A-Gene — Compatible Instrumentation for NTR vectors

Q: What instrumentation is suitable for viewing Ad-A-Gene NTR vector assay results? A: Assays using Ad-a-Gene NTR vectors can be imaged on fluorescence microscopes, IN Cell Analyzer 1000 (using the ...

Amdex Conjugates — Western Blotting Suitability

Q: Are the AMDEX secondary enzyme conjugates suitable for use in Western Blotting applications? A: The Amdex enzyme conjugates are produced for ELISA applications and are not tested or validated for ...

AMDEX Conjugates– Antibody Information

Q. Are the antibodies used to produce the AMDEX antibody conjugates polyclonal or monoclonal in origin? A. All antibodies conjugated to the dextran backbone of our Amdex conjugates are of polyclonal ...

Amdex enzyme conjugates — Recommended dilution range

Q. What dilution range is recommended for use of the Amdex enzyme conjugates in ELISA? A. The Amdex enzyme conjugates should be used at a starting dilution range of 1:4000-1:8000, using 100uL/well. ...

Anti-BrdU Antibody — Use on Paraffin Sections

Q: Can the Anti-BrdU Antibody be used on paraffin-embedded tissue sections? A: The Anti-BrdU Antibody (order code RPN202) can be used on paraffin-embedded tissue sections. However, preparation of the ...

Biotrak Assay Kits — Storage of antibody-coated plate

Q. If only part of the antibody coated plate from a Biotrak Assay is used, how should the plate be stored? A. The partially used antibody coated microtiter plate must be stored carefully sealed and ...

Biotrak Assays — Matrix Effects Definition

Q. What are "matrix effects" and how do they influence Biotrak immunoassay performance? A. By definition, a matrix effect is the combined effect of all components of the sample (other than the ...

Biotrak cAMP and cGMP Assays — Species cross-reactivity

Q. Will the Biotrak cAMP and cGMP assay kits work with samples from all species? A. cAMP and cGMP are ubiquitous analytes that are structurally conserved across species. Therefore, our Biotrak cAMP ...

Biotrak cAMP and cGMP EIA Kits — Kit Stability

Q. For how long is the cAMP and cGMP Biotrak EIA assay kit stable when stored as recommended? A. When stored properly, the cAMP and cGMP Biotrak EIA assay kits are stable for at least 4 weeks from ...

Biotrak cAMP and cGMP EIA kits — Sample Storage and Stability

Q. How long can samples be stored before use with the Biotrak cAMP and cGMP EIA kits? A. Due to the large complexity of most sample extracts, it is difficult to generalize cNMP (cAMP or cGMP) ...

Biotrak cAMP and cGMP EIA Kits — Storage of Reconstituted Reagents

Q. For how long can the reconstituted reagents of the Biotrak cAMP and cGMP EIA kits be stored? A. The reconstituted and undiluted reagents of the cAMP and cGMP EIA kits can be kept for up to 2 weeks ...

Biotrak cAMP and GMP Assays — Acetylation and Sensitivity

Q. Why is the acetylation protocol that is included in some Biotrak cAMP & cGMP immunoassays more sensitive than the non-acetylation protocol? A. Since the cyclic nucleotide itself is not ...

Biotrak cAMP and IP3 Assays — Cell and Tissue Culture Samples

Q. Is it possible to prepare one sample for both Biotrak cAMP and IP3 assays? A. Ice cold TCA extraction would work for both cAMP and IP3 analysis of cell culture samples. We recommend that the cell ...

Biotrak cAMP EIA — Pre-assay Room Temperature Equilibration

Q. Why do the reagents for the cAMP Biotrak EIA have to be equilibrated at room temperature before use, but the assay itself run at 4�C? A. Room temperature equilibration is important in particular ...

Biotrak cAMP EIA — Acetylation Assays using Lysis Reagents

Q. Are the acetylation reagents from the Biotrak cAMP EIA kit compatible with use of the lysis reagents? A. The use of our Direct Assay Technology's lysis reagents in combination with the acetylation ...

Biotrak cAMP EIA — Can heparin or citrate be used as an anticoagulant

Q. Can heparin or citrate be used as an anticoagulant instead of EDTA to collect blood samples for the cAMP Biotrak EIA assay kit (RPN225)? A. Use of heparin or citrate to collect blood in the cAMP ...

Biotrak cAMP EIA — Chemical cross-reactivity

Q. What is known regarding chemical crossreactivity of the Biotrak cAMP EIA kit? A. There is little interference from nucleotide analogues and PDE inhibitors based on crossreactivity of the following ...

Biotrak cAMP EIA — Interfering Compounds

Q. What chemicals and compounds interfere with the Biotrak cAMP EIA assay kit performance? A. The effect of several chemicals commonly used on performance of the Biotrak cAMP EIA assay kit is ...

Biotrak cAMP SPA Assays — Chemical crossreactivity

Q. What is known regarding the chemical crossreactivity of the cAMP SPA screening assay kit (RPA556)? A. Crossreactivity is determined by the concentration giving 50% B/B0 Chemical Cross ...

Biotrak cAMP SPA Assays— Prepareing sample without freeze drying equipment

Q. Can samples for the cAMP SPA screening assay kit (RPA556) be prepared without freeze drying equipment? A. For use with the cAMP SPA screening assay kit (RPN556) we recommend freeze drying of ...

Biotrak Catecholamine Assay Blood Collection Tubes – Components

Q. What are the components in the Biotrak Catecholamine Assay Blood Collection Tubes? A. The catecholamine assay blood collection tube, RPN532, contains 8.1mg EGTA and 5.4mg glutathione. It can hold ...

Biotrak Cell Proliferation — Suitable Sample Types

Q: Can lymphocytes and other cells from any species be used in the Biotrak Cell Proliferation ELISA assay? A: Yes , this kit works with suspension or adherent cells from all species; also, the ...

Biotrak Cell Proliferation — Fixatives

Q: Can cells used in the Biotrak Cell Proliferation Kit be fixed with glutaraldehyde or formalin? A: Glutaraldehyde or formalin fixation may cross-link proteins too strongly, thereby inhibiting ...

Biotrak Cell Proliferation — BrdU and Other Component Stabilities

Q. What is the stability of BrdU Labeling Reagent and the other components of the Biotrak Cell Proliferation Kit and ELISA assays? A. Each batch of the Biotrak Cell Proliferation Kit and the Biotrak ...

Biotrak Cell Proliferation – How long do most cells need to be labeled with BrdU?

Q. How long do most cells need to be labelled with BrdU? A. For most applications, a 2-hour labelling is adequate. Extension of the incubation time will increase the amount of BrdU incorporated into ...

Biotrak Cell Proliferation — Does the antibody cross-react with collagen? Background OD is high

Q. When collagen coated 96-well plates were used for the Cell Proliferation ELISA assay (RPN250) the blank reading was very high (0.7 OD). Does the antibody cross-react with collagen? A. The problem ...

Biotrak Cell Proliferation — Can cells be fixed before labelling with BrdU?

Q. Can cells be fixed before labelling with BrdU? A. No, the cells have to be labelled with the BrdU before fixation as it is incorporated into the DNA as the cell divides. Click here for more ...

Biotrak Cell Proliferation — Preventing adherent cells from detaching

Q. How can I prevent adherent cells from detaching off the plate when fixing the cells as directed using the Cell Proliferation ELISA (code RPN250)? A. This may occur if surface treated plates, ...

Biotrak cAMP and cGMP EIA Kits — Assay for cAMP and cGMP from a single acetylated sample?

Q. Can an acetylated sample be assayed for both cAMP and cGMP using the RPN 225 and RPN226 Biotrak EIA assay kits? A. Unfortunately, this is not possible due to differences in the protocol for sample ...

Biotrak cAMP and cGMP EIA Kits — Assay Buffer Appearance

Q. Does a precipitate or cotton-like appearance in the assay buffer concentrate component of the cGMP or cAMP Biotrak EIA assay kit indicate it is contaminated? A. A fluffy, cottony material or ...

Biotrak cGMP EIA — Acetylation and Sensitivity

Q. Why is the acetylation protocol for the cGMP Biotrak EIA assay kit more sensitive than the non-acetylation protocol? A. Since cGMP itself is not immunogenic, our anti-cGMP antibody was raised ...

Biotrak cGMP EIA — Chemical cross-reactivity

Q. What is known regarding chemical crossreactivity of the cGMP Biotrak EIA kit? A. Crossreactivity of the following purified analogues was determined: Chemical Cross Reactant Non-acetylation ...

Biotrak cGMP EIA — Species crossreactivity

Q. What is the species crossreactivity of the Biotrak cGMP and cAMP assay kits? A. cGMP and cAMP are ubiquitous biochemical analytes that are conserved across all species; therefore, these assay kits ...

Biotrak Cytokine Assays – Are Cytokine "Breakdown" Products Detectable?

Q. Are cytokine "breakdown" products detectable with Amersham Biosciences Biotrak Assay Systems? A. It is possible that cytokine fragments may be present in biological samples. Whether or not the ...

Biotrak Cytokine Assays – Does the presence of cytokine specific soluble receptor interfere with our Cytokine Assay Systems?

Q. Does the presence of cytokine specific soluble receptor interfere with our Cytokine Assay Systems? A. In general, antibody affinity is several orders of magnitude greater than that of receptors, ...

Biotrak Cytokine Assays – How are the Standards Calibrated

Q. How are standards used in the Cytokine Assay Systems calibrated? A. Where reagents are available, our standards are calibrated against cytokine preparations from international agencies. The ...

Biotrak Cytokine Assays – Measurement of "Biologically Active" Mature Cytokine versus Precursor Molecules

Q. Do Amersham Biosciences Cytokine Assay systems measure only "biologically active" mature cytokine? A. Cytokines are generally produced as a precursor molecule with a signal peptide that directs ...

Biotrak Cytokine Assays – Quantitation of Cytokines from other Species

Q. Can Biotrak cytokine assay kits be used to quantitate cytokines from other species? A. Cytokine antibodies are extensively screened to ensure that they are specific for their target. Such highly ...

Biotrak Eicosanoid Assays — High background

Q. What factors may contribute to high backgrounds in the Biotrak Eicosanoid assays? A. If high background is seen only in samples, this suggests some matrix effect is at fault and could relate to a ...

Biotrak II Plate Reader — Changing of additing filters

Q. How do I add or change filters in the Biotrak I Visible Plate Reader? A. It is not difficult to add or change filters in the plate reader. For instructions, please access the attached document. ...

Biotrak II Plate Reader — How many wash cycles can be defined.

Q. How many wash cycles can be defined on the Biotrak II Plate Washer? A. The Biotrak II Plate Washer can store up to 20 wash cycles. Any combination of the wash cycles then can be linked together to ...

Biotrak II Plate Reader — Is warm-up time needed before use?

Q. Is warm-up time needed before operating the Biotrak Plate Reader? A. After switching on the instrument, it is ready for use - no warm-up time is required. Click here for more information about ...

Biotrak II Plate Reader — Lamp life

Q. How long will the lamp for the Biotrak II Plate Reader last? A. The lamp on the Biotrak II Plate reader should last for ~10 million readings. Click here for more information about Biotrak

Biotrak II Plate Reader — MacIntosh Computer-compatibility?

Q. Is the Biotrak II Plate Reader PC-interface compatible with MacIntosh (Apple Inc.) computers? A. No. The Biotrak Plate Reader is not compatible with MacIntosh/Apple computers. The PC interface ...

Biotrak II Plate Reader — Memory and Storage Capacity

Q. How much memory does the Biotrak II plate reader have? A. The plate reader has memory for more than 120 methods and is 1 gigabyte in size. Click here for more information about Biotrak

Biotrak II Plate Reader — Optical density (OD) measuring range

What is the optical density (OD) measuring range of the Biotrak II Plate Reader? The Biotrak II Plate Reader is capable of reading a range spanning 0.000-4.000 OD absorbance units Click here for more ...

Biotrak II Plate Reader — Possible curve-fitting methods.

Q. What curve-fitting methods are possible using the Biotrak Plate Reader? A. The Biotrak Plate Reader contains pre-programmed data reduction methods including linear regression, point-to-point, ...

Biotrak II Plate Reader — Selecting a printer

Q. How do I select a printer using the Biotrak I Plate reader? A. On the Biotrak Plate Reader, press the Menu key, then go to the Setup/System. Scroll down (by pressing the enter key) to Printer ...

Biotrak II Plate Reader — What are the four factory-installed filters

Q. What are the four factory-installed filters in the Biotrak Plate Reader? A. The four filters supplied as standard are 405, 450, 492, and 620nm. Additionally, the filter wheel can hold up to 8 ...

Biotrak IP3 Assay – Sample Preparation for Cells

Q. How many cells per data point are recommended for the Biotrak IP3 assay? A. For assaying cell culture samples with the Biotrak IP3 assay kit, use between 10^5 to 10^7 cells for extraction. This is ...

Biotrak MMP-13 ELISA — Normal Serum and Plasma Values

Q. What are the expected values for MMP-13 in normal serum and plasma using the Biotrak MMP-13 ELISA? A. Tamei et al. (see belwo reference) published their findings that normal serum MMP-13 levels in ...

Biotrak MMP-2 ELISA — Differences between MMP-2 ELISA and Activity Assay Measurement

Q. What are the differences in sample readings between the MMP-2 ELISA (RPN2617) and the MMP-2 Activity Assay (RPN2631)? The pack leaflets state that a typical sample gives higher ELISA levels ...

Biotrak MMP-3 and MMP-1 Assays— Synovial Fluid Samples

Q. Have the MMP-3 or MMP-1 ELISA or Activity Assay kits been used with synovial fluid? A. The Biotrak MMP-3 ELISA has been used successfully with synovial fluid. Information relating to this can be ...

Biotrak MMP-9 Activity Assay — Reported species cross-reactivity

Q. What is the reported species cross-reactivity of the Biotrak Human MMP-9 Activity Assay (RPN2634) ? A. The human MMP-9 activity assay (RPN2634) is specific for human MMP-9, but it does cross-react ...

Biotrak MMP-9 ELISA — Serum Samples

Q. Can the Biotrak MMP-9 ELISA be used to measure MMP-9 in serum samples? A. The Biotrak MMP-9 ELISA is recommended for measurements in plasma, cell culture and tissue homogenates. In a recent ...

Biotrak MMP-9 ELISA — What parts of the MMP-9 protein do the ELISA antibodies react with?

Q. What parts of the MMP-9 protein do the ELISA antibodies react with? A. Both antibodies are raised against whole pro MMP-9. From Western Blotting experiments we know that the detection antibody ...

Biotrak MMP Activity Assays — Increasing sensitivity

Q. Is it possible to increase the sensitivity of the MMP activity assays? A. The sensitivity of MMP activity assays may be increased by simply extending the assay incubation time. The longer the ...

Biotrak MMP Activity Assays– Use of EDTA or Other Metal Chelators in Samples

Q. Will the use of EDTA and other metal chelators for sample preparation affect MMP assay readout? A. Since MMPs (matrix metalloproteinases) are zinc dependant enzymes, EDTA should not be present in ...

Biotrak MMP ELISA Assays – Recommended Storage Conditions for Plasma Samples and Stability

Q. Recommended Storage Conditions for Plasma Samples and Stability A. MMP’s are very active enzymes possessing natural autocatalytic properties and as such are prone to degradation. We recommend that ...

Biotrak MMP ELISA Assays — Species cross-reactivity

Q. What species cross-reactivity can be expected with the Biotrak MMP ELISA kits? A. ELISAs by their very nature are highly specific . Although several species have been tested, the majority of ...

Biotrak PGE2 (RPA530) — Stability of kit components

Q. What is the stability of the PGE2 (RPA530) kit components? A. All of the components in the kit with the exception of the tracer have been tested for up to 30 weeks. The methyloximation reagent has ...

Biotrak Plate Washer — How to program for partial plate wash.

Q. How do I program the Biotrak Plate Washer to do a partial plate wash? A. Program the Biotrak Plate Washer to do a partial plate wash as follows: 1) Select the Wash procedure on the Run Procedure ...

Biotrak Plate Washer — Use with reduced diamete 96-well plates.

Q. Can the Biotrak Plate Washer accomodate 96-well plates which have reduced diameter wells? A. Yes. The plate washer can be set up for this and a variety of other plates. The position of the ...

Biotrak Plate Washer — What is automatic well-bottom detection and how does it work.

Q. What is automatic well-bottom detection and how does it work on the Biotrak II plate washer? A. The dispensing manifold in the Biotrak II Plate Washer has a sensor which detects the plate bottom ...

Biotrak Rat Hormone Assays – Cross-reactivity with Mouse Samples

Will the Biotrak rat hormone assays work with mouse samples? Q. Do the Biotrak Rat Hormone assays have cross-reactivity for mouse samples? A. We have not validated the cross-reactivity of the Biotrak ...

Biotrak TIMP-1 ELISA — Measurable forms of TIMP-1

Q. What forms of TIMP-1 can be measured using the TIMP-1 ELISA? A. The TIMP-1 ELISA will measure free TIMP-1 and TIMP-1 that is complexed with active and pro-MMPs. It should be noted that only MMP-9 ...

Biotrak TIMP-2 ELISA — Species Crossreactivity

Q. Will the Biotrak human TIMP-2 ELISA cross-react with samples from other species? A. The TIMP-2 peptide epitopes which were used to raise antibodies are conserved across species. Therefore, the ...

BrdU Labeling Reagent — Formulation and Concentration

Q. What is the concentration and formulation of the BrdU Labeling Reagent? A. The BrdU Labeling Reagent (code RPN201) contains 10mM BrdU (~3mg/mL) and 1mM FdU (~0.3mg/mL) in water. Click here for ...

Biotrak Cell Proliferation — Extending the BrdU Incubation Step

Q. Can the BrdU incubation step in the Biotrak Cell Proliferation Assay be extended for longer time? A. Yes, the incubation can be extended up to 24 hours. The incubation time needs to be determined ...

Cell Proliferation Labeling Reagent — BrdU half-life in vivo

Q. What is the in vivo half-life of BrdU in rats? A. The in vivo half-life of BrdU is 30 minutes. Click here for more information about Biotrak.

MAP Kinase SPA – Purchasing the Biotinylated MBP Substrate Separately

Q. Can I purchase the biotinylated myelin basic protein (MBP) substrate from the MAP SPA Kinase kit separately? A. The biotinylated MBP substrate is supplied in this kit (MAP Kinase SPA Assay, code ...

Biotrak MMP Activity Assays — Cloudy Wash Buffer

Q. Why does the wash buffer for the MMP Activity assays appear cloudy? A. The wash buffer for the MMP Activity assays may be cloudy due to Tween20 detergent in the concentrated solution. The ...

SPA Beads — SPA vs liquid scintillation counting efficiency

Q. What is the difference in SPA counting efficiency as compared to liquid scintillation counting? A. SPA counting is not as efficient as liquid scintillation counting. Typically, counting efficiency ...

SPA Beads – 'Non-Proximity Effect' and How Can it be Minimized?

Q. What is meant by the term 'non-proximity effect' and how can it be minimized? A. A non-proximity effect, or "NPE", is low-level background signal caused by stimulation of SPA beads by unbound ...

SPA Beads – Average PVT and YSi Bead Size

Q. What is the average size of the YSi and PVT SPA beads? A. The yttrium silicate (YSi) and polyvinyl toluene (PVT) SPA beads range in size from 2-8�m. The PVT SPA beads average approximately 5�m in ...

SPA Beads – Detection of Gamma Emitters

Q. How does SPA work with gamma emitters? A. [125I ] and other gamma emitters decay by a process termed "electron capture". This type of decay gives rise to particles named Auger (pronounced ...

SPA Beads – Maximum centrifuge speed to spin down SPA beads

Q. What is the maximum centrifuge speed I can use to spin down the SPA beads? A. As a rule of thumb treat the SPA beads as you would cells, spinning at no more than 2,000 rpm in a standard centrifuge ...

SPA Beads – Mechanism of Membrane binding to WGA and Polylysine SPA beads?

Q. What is the mechanism of cell membrane binding to Wheat Germ Agglutinin and Polylysine SPA beads? A. Cell membranes couple to the wheat germ agglutinin (WGA) coated SPA beads through interactions ...

SPA Beads – Storage stability of the antibody-coated PVT and YSi SPA beads?

Q. What is the storage stability of the antibody-coated PVT and YSi SPA beads? A. In lyophilized form, the antibody coated SPA beads should be stable 6-12 months. Once reconstituted, storage at 2 - ...

SPA Beads – What concentration of SPA bead and membrane should I use in a receptor binding SPA assay?

Q. What concentration of SPA bead and membrane should I use in a receptor binding SPA assay? A. Perform an initial matrix experiment to determine the optimum amount of membrane and bead to use in the ...

SPA Beads – What Fluor or Scintillator is present in the PVT and YSi SPA beads?

Q. What fluor or scintillator is present in the PVT and YSi SPA beads? A. The scintillator in the PVT beads is diphenylanthracine (DPA), which is co-polymerized in the polyvinyl toluene matrix. In ...

SPA Beads – What time-of-addition format should I use to develop a receptor binding SPA assay?

Q. What time-of-addition format should I use to develop a receptor binding SPA assay? A. There are three time-of-addition formats used for establishing a receptor binding assay, each with its own ...

SPA Beads –"Order of addition" in Assays

Q. Will simultaneous addition (T=0) , delayed addition, and pre-coupled SPA bead receptor binding assay formats yield similar signals in an assay? A. Unfortunately, there is no strict rule or ...

SPA Beads — Coupling Receptor Preparations to Beads

Q: Do I need to remove uncoupled or unbound cell membrane from SPA beads before use in a receptor binding assay? A: Removal of unbound membrane preparation from the SPA beads is not generally ...

SPA Beads — Nature of Bead Coating

Q: How are proteins and other molecules linked or coated onto SPA beads? A: Proteins or other macromolecules are covalently linked to SPA beads (PVT, PS, YSi, or YOx) in one of two ways: 1) by direct ...

SPA Beads — Liquid scintillation counter window settings

Q. What liquid scintillation counter window settings do I need to use for counting an SPA assay? A. For counting SPA assays in a liquid scintillation counter or instruments other than the Packard ...

TRK1000 IP3 [3H] Assay – Sample pH range tolerance

Q. What sample pH range will the Biotrak IP3 [ 3H ] assay (TRK1000) tolerate? A. The assay buffer is pH 9.0, which is the pH optimum for the IP3 assay. The assay could tolerate samples neutralized to ...

Biotrak II Plate Reader — What printers can be used

Q. What printers can be used with the Biotrak Plate Reader? A. The following printers or printer-types can be chosen from the Biotrak Plate Reader setup screen: Laser, 9-pin or 24-pin matrix printer, ...

Biotrak MMP Activity Assays – Increasing the detection enzyme incubation step in the MMP Activity Assays to increase assay sensitivity

Q. Will increasing the detection enzyme incubation step in the MMP Activity Assays increase assay sensitivity? A. Absolutely, and in fact, in many cases this is necessary. More times than not, this ...

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