Pseudo first order reaction for an organic reaction

[Jikson P Mathew]

Hello all,

I would like to know how we can write a pseudo-first-order reaction in COPASI in case of an organic reaction.

Also, are the following assumptions correct as per the COPASI program:

A -> B

is a first-order reaction.

A + B -> C

is a second-order reaction.

All the above assumptions are made for a time course-based parameter estimation and the rate law used is Mass action (irreversible).

Thank you for your time.

Best regards,

Jikson

[Pedro Mendes]

Hi Jikson,

A pseudo-first order reaction is written the same way as a true
first-order reaction, except that you leave out the species that is
ommitted.
"Pseudo first-order" refers to a reaction of higher order that is
written as first-order. This means that some reactants are going to be
omitted and included in the rate constant. (This is only valid if the
concentration of the reactants omitted is constant or nearly constant)

Example:

original reaction A + B -> C rate constant k
reaction rate: [A]*[B]*k

pseudo-first order (given B almost constant)
reaction: A -> C rate constant k' (k'=k1*[B])
reaction rate: [A]*k'

The assumptions you wrote below are correct

> A -> B is a first-order reaction.

> A + B -> C is a second-order reaction.

Pedro

--
>
Pedro Mendes, PhD
Professor and Director,
Richard D. Berlin Center for Cell Analysis and Modeling
University of Connecticut School of Medicine
group website: http://www.comp-sys-bio.org