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Looking for SIGMAFAST™ p-Nitrophenyl phosphate Tablets N2770

Doron scientific supply SeramunGelb® fast, ELISA Substrates for alkaline phosphatase (AP)

Major benefits:

· Ready-to-use

· High lot-to-lot consistency

· High colour stability after reaction stop

· Long shelf life up to 36 months

· Long term stability at room temperature

· High absorbance yield without precipitation

· In stock

Doron scientific is pleased to offer SeramunGelb® fast, SeramunGellb ® fast the ready-to-use pNPP/Substrate Solution for ELISA p-Nitrophenylphosphate (pNPP) is the most commonly used substrate for alkaline phosphatase (AP) in enzyme immunoassay techniques. The phosphate residue is ester interchanged by the AP to an acceptor, preferably amino alcohols. The colourless solution turns into the intensive yellow colour of p-nitrophenol. The results reported here are mainly based on experimental data obtained from Seramun Diagnostica GmbH. Customers have also confirmed the properties of SeramunGelb® fast demonstrated in this report. At present, a growing number of ready-to-use pNPP solutions are available. An optimized buffer system enhances the activity of the alkaline phosphatase and reduces spontaneous hydrolysis of pNPP. The non-hazardous, non-aggressive and non-flammable solution guarantees the safety of transport and of use in the laboratory. SeramunGelb® fast is produced according to a standardized operating procedure that guarantees a high lot-to-lot consistency. In this report, we compare SeramunGelb® fast with pNPP substrate tablets from Sigma and with ready-touse substrate solutions from Moss, SurModics Inc. (formerly BioFX Laboratories) and KemEnTec.

· High absorbance yield comparable to freshly dissolved pNPP tablets

· Broad measurement range

· Low blank drift during long-term storage (<0.2 AU within 12 months)

· High colour stability after reaction stop with SeramunGelb® stop and other used stopping solutions

Ordering Information

Order No.


SeramunGelb® slow (ELISA), 100 ml

pNPP/substrate solution, ready-to-use

100 ml

SeramunGelb® slow (ELISA), 250 ml

pNPP/substrate solution, ready-to-use

250 ml

SeramunGelb® slow (ELISA), 1 Liter

pNPP/substrate solution, ready-to-use

1 Liter

SeramunGelb® slow (ELISA), 5 Liter

pNPP/substrate solution, ready-to-use

5 Liter

SeramunGelb® slow (ELISA), 10 Liter

pNPP/substrate solution, ready-to-use

10 Liter

SeramunGelb® slow (ELISA), 20 Liter

pNPP/substrate solution, ready-to-use

20 Liter

SeramunGelb® slow (ELISA), 30 Liter

pNPP/substrate solution, ready-to-use

30 Liter

SENSITIVITY OF SERAMUNGELB® FAST A highly active substrate is essential for ELISA tests demanding high sensitivity and steep standard curves. Furthermore, short substrate reaction times contribute to reduce the overall assay time as well as the conjugate concentration. The latter point is of importance to prevent background problems and may help to reduce reagent costs. Kinetic measurement of substrate reaction Substrate conversion was monitored by the following procedure: microtitration plates (Nunc, Maxisorp) coated with 10 µg/ml human IgG were incubated for 60 minutes at room temperature with 100 µl of antihuman IgG-AP conjugate (Seramun) adjusted to a concentration of 0.10 µg/ml and 0.05 µg/ml respectively. After washing the wells five times, the substrate reaction was started by addition of 100 µl SeramunGelb® fast. Absorbances were recorded at 405/620 nm wavelength every 5 minutes over a period of 45 minutes.

Substrate activity SeramunGelb® in comparison to competitor products Microplate coated with human-IgG, 60 min incubation with anti-human-IgG-AP-conjugate (0.05 µg/ml), 5x wash, start of substrate reaction

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