well well! there are other ways to do this N/P calculations.

if you really want to consider no. of N gps participating in interaction with P gps

follow this:

Nomenclature for synthetic gene delivery systems.

Felgner PL, Barenholz Y, Behr JP, Cheng SH, Cullis P, Huang L, Jessee JA, Seymour L, Szoka F, Thierry AR, Wagner E, Wu G.

Hum Gene Ther. 1997 Mar 20;8(5):511-2.

and

Efficient transfer of genetic material into mammalian cells using Starburst polyamidoamine dendrimers

Kukowska-Latallo JF, Bielinska AU, Johnson J, Spindler R, Tomalia DA, Baker JR Jr.

Proc Natl Acad Sci U S A. 1996 May 14;93(10):4897-902.

long story short:

1.0 μg of DNA is 1.71×10^15, so 1.71×10^15 negative charges

1 ug of DNA contains 3 nmol of phosphate

what about if the strand is 5'dephosphorylated...?

Barichello et al cite Boussif if i am correct. I also mention and cite Boussif in my PEI paper.

If it is dephos-ed... it is only one single phosphate group at the end. Wont make a noticable different.

I thank you all for sharing information.

Thanks Shivangi for the reference. My query is solved.

http://www.gvt-journal.com/content/5/1/11/abstract/

well well! there are other ways to do this N/P calculations.

if you really want to consider no. of N gps participating in interaction with P gps

follow this:

Nomenclature for synthetic gene delivery systems.

Felgner PL, Barenholz Y, Behr JP, Cheng SH, Cullis P, Huang L, Jessee JA, Seymour L, Szoka F, Thierry AR, Wagner E, Wu G.

Hum Gene Ther. 1997 Mar 20;8(5):511-2.

and

Efficient transfer of genetic material into mammalian cells using Starburst polyamidoamine dendrimers

Kukowska-Latallo JF, Bielinska AU, Johnson J, Spindler R, Tomalia DA, Baker JR Jr.

Proc Natl Acad Sci U S A. 1996 May 14;93(10):4897-902.

long story short:

1.0 μg of DNA is 1.71×10^15, so 1.71×10^15 negative charges

That is such a nice simple way of thinking about it.