The Citric Acid test kit is a flexible and simple method for the rapid and reliable measurement and analysis of citric acid (citrate) in foods, beverages and other materials.
Short term stability: 2-8oC, Long term stability: See individual component labels
Stability:
> 2 years under recommended storage conditions
Analyte:
Citric Acid
Assay Format:
Spectrophotometer, Microplate, Auto-analyser
Detection Method:
Absorbance
Wavelength (nm):
340
Signal Response:
Decrease
Linear Range:
1.0 to 100 µg of citric acid per assay
Limit of Detection:
0.491 mg/L
Reaction Time (min):
~ 5 min
Application examples:
Grape juice, wine, beer, fruit juices, soft drinks, tea, dairy products (e.g. cheese), meat, processed meat, vegetable and fruit products, bakery products, paper, pharmaceuticals, cosmetics and other materials (e.g. biological cultures, samples, etc.).
Method recognition:
Methods based on this principle have been accepted by MEBAK, OIV, EU, ISO2963, AOAC and IFU22 (NOTE: If the enzyme oxaloacetate decarboxylase is present in the sample, some of the oxaloacetate product is converted to pyruvate. Therefore, to ensure citric acid is measured quantitatively, D-lactate dehydrogenase (D-LDH) is employed to efficiently convert any pyruvate produced into D-lactate and NAD+).
The Citric Acid test kit is a flexible and simple method for the rapid and reliable measurement and analysis of citric acid (citrate) in foods, beverages and other materials.
Note for Content: The number of manual tests per kit can be doubled if all volumes are halved. This can be readily accommodated using the MegaQuantTM Wave Spectrophotometer (D-MQWAVE).
Extended cofactors stability. Dissolved cofactors stable for > 1 year at 4oC.
Reconstituted citrate lyase stable for 4 weeks at 4oC / 6 months below -10oC
Buffer / cofactor / enzyme tablets for efficient use of kit components
PVP incorporated to prevent tannin inhibition
Very competitive price (cost per test)
Mega-Calc™ software tool is available from our website for hassle-free raw data processing
Standard included
Suitable for manual, microplate and auto-analyser formats
Other Products
APOPercentage apoptosis assay kit
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Product Info
What is Apoptosis?
Apoptosis is an essentially normal physiological process that removes now redundant, cells, particularly during embryonic development and early growth. In adult animals the process removes cells that are irreparable. The apoptotic process is also involved in many major diseases such as cancer, where transformed tumour cells have their apoptotic process disabled, permitting cell cycling to continue unchecked. In contrast some forms of senile dementia may result from excessive apoptotic induction of neural cells.
The apoptotic process in mammalian cells is a rapid event (2‐4 hours). Within this short time span an apparently viable cell can be quietly dismantled, to disappear leaving no visible trace of its former existence.
How is apoptosis detected or measured?
An apoptosis cascade of activators, effectors and regulators has been identified. This in turn led to a range of apoptosis assays being devised to detect and monitor these events. Some laboratories will employ two distinct assays, one selected to detect early (initiation) apoptotic events, while a second assay will target a later (execution) event. Apoptosis assays, based on methodology, can be classified into four major inter‐linked groups:
[1] DNA fragmentation (electrophoresis and nick end labelling, TUNEL).
[2] Apoptotic proteases (fluorescently labelled antibodies to the caspases).
[3] Flow cytometric analysis (FACS, incorporating other group assays).
Biocolor’s APOPercentage assay is based on the latter. Further information can be found under the ‘Mode of Action’ Tab.
How does APOPercentage detect apoptosis?
The mammalian cell membrane has been described as a semi‐fluid mosaic structure, composed of phospholipids with a diverse group of inserted proteins and some cholesterol. The phospholipids are the major components of the membrane and are arranged in the form of a ‘bi‐layer’; which is asymmetric in composition, structure, and function.
To ensure normal transmembrane functions the phospholipids must be maintained in an asymmetric composition. The process is regulated by ‘flippases’, which catalyse the active transport of aminophospholipids from the outer to inner monolayer. However, in cells undergoing apoptosis, flippase is overwhelmed by the action of another enzyme, termed ‘floppase’ or ‘scramblase’. The net effect is a scrambling of the phospholipid distribution between the inner and outer monolayers.
Cell membrane changes during apoptosis
The APOPercentage assay utilises an intense, pink-coloured dye reagent which is taken up during in-vitro culture by apoptosis-committed cells. This uptake occurs at the stage of Phosphatidylserine transmembrane movement, as produced by the flipflop mechanism. Dye uptake continues until blebbing occurs. No further dye can then enter the now defunct cell and the dye that has accumulated within the cell is not released (unlike necrotic cells which release dye).
Since the dye reagent is excluded or not retained by healthy or necrotic cells it therefore acts as a specific label for apoptotic cells.
How are APOPercentage-labelled cells quantified?
Labelled apoptosis cells may then by conveniently analysed by the following methods:
Direct Analysis The intense pink colour of the labelled cells can be visually assessed using brightfield microscopy. Apoptosis in substrate-adherent cell populations is therefore readily quantified using image analysis techniques. This technique is the most sensitive with the ability of detecting one single apoptotic cell per well.
Colorimetry protocol Dye that accumulates within apoptotic cells is released into solution via addition of Dye Release Reagent. The concentration of this intracellular dye is then measured at 550nm using a microplate colorimeter/spectrophotometer.
NB: The APOPercentage assay kit does NOT require the use of a Flow Cytometer.
Limit of Detection
A single cell (via image analysis method)
Detection Method
Colorimetric (550nm) (Endpoint) or Image Analysis based
Measurements per kit
Sufficient for 4×24 well plates or 6×96 well plates
Suitable Samples
Adherent mammalian cells (in-vitro)
APOPercentage kit contents:
1. APOPercentage Dye (1x5ml)
2. Dye Release Reagent (1x150ml)
3. Phosphate Buffered Saline (PBS) (1x120ml)
4. 24-well starter plate.
5. Assay kit manual.
The Colorimetric Protocol requires a Microplate Colorimeter / Spectrophotometer.
Additional 96-well plates will be required for use when reading dye absorbance values.
The Direct Detection Protocol Requires an inverted stage microscope with an attached digital camera.
NB: Additional reagents (typically culture medium and suitable apoptosis treatments) may be required for sample preparation prior to assay. Consult manual or contact us for further details.
Document
The APOPercentage™ Apoptosis kit is a dye-based, colorimetric assay for detection and measurement of apoptosis (programmed cell death) during in-vitro cell culture.
This ELISA kit is intended for the quantitative detection of IgG antibodies against Schistosoma mansoni and Schistosoma haematobium in human serum.
This product is manufactured by Bordier Affinity Products in Switzerland and distributed in Germany exclusively by Milenia Biotec.
Method/Platform
ELISA in microplate format
Range/Assay Sensivity
pNPP, λ=405 nm
Test Principle
Specific antibodies in the sample will bind to Schistosoma mansoni antigens sensitized on microtiter plates. The presence of parasite specific antibodies is detected with a Protein A alkaline phosphatase conjugate.
12 x 8 strips (96 tests)
This ELISA kit is intended for the quantitative detection of IgG antibodies against Schistosoma mansoni and Schistosoma haematobium in human serum.
NGS Library Quantification Kit (for Small RNA-Seq)
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Product Info
Overview
Able to quantify NGS Library (Illumina) of a wide spectrum of concentrations, including sub-nanomolar concentrations
DNA is accurately quantified by using a standard curve constructed from the provided DNA Standards
Specially designed DNA standards for Small RNA-Seq library; also compatible to NGS library of other molecular weights
Norgen’s NGS Library Quantification Kit (for Small RNA-Seq) offers a PCR-based detection procedure to quantify NGS libraries (specifically Small RNA-Seq) of a wide spectrum of concentrations. The kit consists of a specially designed primer mix compatible with the Illumina system, that is used in conjunction with the provided 2X Real-Time PCR Master Mix to amplify a library of unknown concentration. The unknown library is accurately quantified by using a standard curve constructed from the provided DNA Standard (range from 20 pM to 2 fM) on a Real-Time PCR System. The kit is specially optimized to quantify Small RNA-Seq libraries with DNA standards that have similar size to a Small RNA-Seq library. However, it could also be used with other types of NGS libraries.
Storage Conditions Upon receipt, store Norgen’s NGS Library Quantification Kit (for Small RNA-Seq) at -20°C or lower. Avoid multiple freeze-thaw cycles. If needed, prepare smaller working aliquots and store at -20°C or lower.
