RSC Advances
Paper
temperature increase is having very slight effect over the reac-
tivity of UDMH present in UH25.
8. RSD for all the three hydrazines is found to be not more
than 1.5% when spiked in tap water.
C. Analytical characteristics. Similar to hydrazine & MMH
trials, DA also increases on increasing the concentration from
0.004 to 0.1 M. Calibration graphs of percent absorbance change
versus concentrations were obtained covering the dynamic range
of 0.001–0.1 M in two linear segments, 0.001 M to 0.01 M and
0.02 M to 0.1 M as shown in Fig. S9 & S10 of ESI.† The minimum
detection limit obtained from practical trials is 1 mM for both
nano & conventional Pani systems. R.S.D for ve replicate
determinations of 0.02 M of UH-25 by using nano Pani and
conventional Pani at 50 ꢀC is 0.8 and 1.2% respectively (Table 1).
8. Conclusions
A simple mixture of solution (Pani–CDNB) for the detection of
hydrazines is presented which shows distinct colour change
from blue to green and used to determine hydrazines at mM
concentration levels. In addition, this paper has also demon-
strated that the ability and advantages of this kinetic method as
a very attractive and excellent technique for the analysis of
derivatives of hydrazine. This indicates the method selectivity to
these analytes.
6. Application of the method
Acknowledgements
To evaluate the analytical applicability of the method, the
proposed procedure was applied for determination of hydra-
zines in tap water. As a result, known amount (in two different
trials) of hydrazine, MMH and UH25 was spiked into tap water
separately. RSD for four replicate determinations of each solu-
tion using nano and conventional Pani systems at 50 ꢀC was
calculated and shown in Table S2 of ESI.† From this table, it is
found that RSD for all these trials is not more than 1.5% that
conrms the reliability of the proposed method. This indicates
that there is no serious interference in tap water samples.
One of the authors (Mr S. Selvakumar) wishes to acknowledge
the support rendered by B. Veera Prakash, Research Scholar at
CLRI-CSIR, Technical apprentices (S. Gurunadh & P.V.D. Kan-
naiah) during this study and acknowledges the constant
encouragement by Dr M.Y.S. Prasad, Director, SDSC-SHAR
Centre and Prof. Dr Asit Baran Mandal, Director, CSIR-CLRI,
Chennai.
References
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1. Reactivity is increased in the order of hydrazine, MMH and
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27412 | RSC Adv., 2014, 4, 27404–27413
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