Dead time determination and its influence to retention index in GC system using polar capillary column

Rinaldi Idroes, Frida Oesman


In this research for the determination of dead timeused a method that is mathematically calculated as iteration and linearization of the polar capillarry column  in  Gas  Chromatography  (GC)  type  DN-Wax,  by  injecting  the  homologous series  of  n-alkanes  (n-pentane  up  to  n-decane)  on  GC  system.  The  dead  time values  obtained  are  then  used  to  determine  the  Kovats  Retention  Index (Retention  Index,  RI).  The  results indicated that the  retention index  had  values of  systematic  error  those  are  more  accurate  than  the  retention  time  (tR), corrected retention time (tR') and retention factor(k'), but the retention index shows  the  value  of  random  error  slightly  larger  than  with  other  retention parameters. In this study  the average values obtained by the iteration method, the  dead  time  was  3.52  minutes  with  a  correlation  coefficient  of  0.9998.

Retention  index  values  obtained  are  at  the  confidence  level  92.11%-97.06% with the systematic errors 2.04%-7.89%, while the linearization method showed the average value of the dead time 3.3 minutes witha correlation coefficient of 0.9992,  but  the  value  of  retention  index  values  obtained  show  that  the systematic error is very large.

Key words:Dead time, Retention Index, Homologous Series, GC

Full Text:



Al-Thamir, W.K., Purnell, J.H., Wellington, C.A., and Laub, R.J., 1979, Evaluation of Dead Space in Chromatographic Systems, J. Chromatography173, 388.

Bellas, T.E., 1975, A Computer Program for Calculating Linear and Logarithmic Retention Indices in Gas Chromatography, Chromatographia8, 38.

Berendsen, G.E., Schoenmaker, P.J., de Galan, L., Vigh, G., Varga-Puchony, Z., and Inczedy, J., 1980, On the Determination of the hold-up time in Reversed-Phase Liquid Chromatography, J. of Liquid Chromatography, 3(11), 1669-1686

Dominguez, J.A., and Masa, D.J.C., 2001, Hold-Up Volume Concept in Coloumn Chromatography, Pure Appl. Chem, 73,6, 969-992

Furr, H. C., 1989, Calculation of Chromatographic Dead Times and Retention Indices with the Aid of a Computer Program in BASIC, Journal of Chromatographic Science, 27

Garcia Dominguez, J.A., Garcia Munoz, J., Fernandez Sanchez, E., and Molera, M.J., 1977, Retention of Methane in Gas-Liquid Chromatography -New Evaluation Methods of the Mathematical Dead Time, J. of Chromatographic Science15, 520.

Gassiot, M., Guardino, X., Albaiges, J., Firpo, G.,and Rodriguez-Vinals., 1978, Letter to the Editor : Determination of the Dead Time, J. of Chromatography147, 540.

Guardino, X., Albaiges, J., Firpo, G., Rodrigues-Vinals, R., and Gassiot, M. 1976, Accuracy in the Determination of Kovats Retention Index, J. of Chromatography 118, 13

Haken, J.K., Wainwright, M.S., and Smith, R.J., 1977, A Problem of Accuracy of Mathematical Dead-Time Estimation, J. of Chromatography, 133, 1.

Idroes, R., 2009, Evaluasi Waktu Mati Kromatografi untuk Penentuan Indeks Retensi pada RPHPLC Menggunakan Beberapa Deret Homolog, Majalah Farmasi Indoensia, 20 (3) J. A. García-Domínguez, J. E. Quintanilla-López, R.Lebrón-Aguilar. 1998, J. Chrom., A 803, 197

Kovats, E., 1958, Gas-chromatographische Charakterisierung organischer Verbindungen, Teil 1: Retentionsindices aliphatischer Halogenide, Alkohole, Aldehyde und Ketone, Helvetica Chemica Acta, Vol XLI, No. 206 (1058) 1915-1932

Lopez, Q.J.E., Aguilar, L.R., and Dominguez, G.J.A., 1997, The hold-up time in Gas Chomatography, II. Validation of the Estimation based on the Concept of a Zero Carbon Atoms Alkane, Journal of Chomatography A, 767, 127-136

Mc Nair, H., Miller , J. M., 2009, Basic Gas Chromatography, second edition, Jonh Wiley and Sains Möckel, H.J., Dreyer, U., and Melzer, H., 1992, On the Determination of the Column Dead Volume from Homologous Series, Fresenius J. Analytical Chemistry, 342, 673- 677

Rimmer, C.A., Simmons, C.R., and Dorsey, J.G., 2002, The measurement and meaning of void volumes in reversed-phase liquid chromatography, J. of Chrom. A, 965, 219–232

Torres P.S., Lapasio, T.J.R, Baeza, B.J.J., and Cogue, G.A.M.C., 2009, Altenating Iterative Regression Method for Dead Time Estimation from Experimental Designs, Anal Bioanal Chem, 394 : 625-636

Toth, A. and Zala, E., 1984, Contribution to the Calculation of the Constants of the n-Alkane Retention Time Curve and Gas Hold-Up Time in Gas-Liquid Chromatography, J. of Chromatography, 284, 53.

Touabet, A., Ahmed, A.Y.B.H., Maeck, M., and Meklati, B.Y. 1986, Mathematical Dead-time Determination and Calculation of the Constants of the n-Alkane Retention Time Curve on OV Poly Methyl Phenylsilicone Stationary Phase in Gas Chromatography, J. High Res. Chromatogr. Chromatogr. Commun9, 456.



  • There are currently no refbacks.


Creative Commons License
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

Indonesian J Pharm indexed by:

analytics View My Stats