NADPH RapidStart regeneration system for long-term metabolism

Drug discovery

RapidStart stabilityNADPH is a critical cofactor supporting numerous biochemical reactions. In ADME-Tox studies, NAD(P)H regeneration is strongly recommended when using drug metabolizing enzymes (ex. Cytochrome P450 (CYP), Flavin-containing MonoOxygenases (FMO)), Recombinant CYPs (incl. bactosomes) or cellular fractions (Microsomes, S9).  Currently, the most simple and cost-effective way to regenerate the NAD(P)H in situ and enzymatically is to use the commercially-available RapidStart™ NADPH Regenerating System (Xenotech-Sekisui).

RapidStart uses an enzymatic reaction that changes NADP to NADPH, which is then oxidized by CYPs back to NADP, and the cycle continues…

RapidStart™ is a versatile system that supports the long-term metabolism of test articles by drug metabolizing enzymes and sub-cellular fractions for in vitro drug assays. The system is based on Glucose-6-Phosphate DeHydrogenase (G6PDH) and Glucose-6-Phosphate (G6P), with reduction of NADP+ to NADPH. A most interesting advantage is that it’s extremely simple to use – just add water and use it!

NADPH RapidStart regenerating – versatile & simple ready-to-use system

RapidStart™ NADPH regenerating system is flexible since the end-user can conveniently modulate and adjust the NADPH concentration by simply adding water to it.

Simple protocol work flow: Add – Agitate – Activate!

  1. Determine the desired initial concentration using our RapidStart™ Dilution Concentration Tables (see below)
  2. Add the appropriate amount of high purity water in one single 0.3mL or 1.5 mL vial
  3. Vortex until pellets are fully dissolved & the NADPH regenerating system is activated and is ready for use!

RapidStart dilution table

Once activated, RapidStart™ maintains a suitable concentration of NADPH for 12 hours at room temperature or 48 hours at 2-4°C, allowing for multi-day use of the NADPH regenerating system.

What about you? Which NADPH method are you using in your ADME-Tox studies? Feel free to leave a message below to share your experience or to contact me for more information.

Written by Isabelle Nobiron, PhD
Isabelle is a Product Manager at tebu-bio, and also the company's ISO Quality Manager.