hybrid membranes, different weight amount of samples (10–
10 000 mg mlꢂ1) were incubated with E. coli in aqueous LB broth
for 24 h. 100 mL aliquots were placed on nutrient soft agar
plates followed by incubation at 37 ꢀC for 24 h, for bacterial
colony counting. APDSMO and hydrolysed APDSMO showed
bactericidal properties, while hybrid membranes exhibited
bacteriostatic properties. Bacteriostatic properties were
confirmed by calculating percentage growth inhibition
(Table 3). APDSMO solution (5000 mg mLꢂ1) showed complete
growth inhibition for microbes. Antifungal activity of
APDSMO and hydrolysed APDSMO was also confirmed by
reported method.34 Results present in Table 2 revealed anti-
fungal activity of APDSMO and hydrolysed APDSMO in four
different concentrations (10–5000 mg mlꢂ1). At 5000 mg mlꢂ1
concentration, APDSMO and hydrolysed APDSMO, showed
complete fungal growth inhibition (experimental picture
included in Fig. 11). Fluconazole and streptomycin was used as
reference drug for antifungal and antibacterial activity. Mech-
anism of antimicrobial activity for APDSMO and hydrolysed
APDSMO is not known, but particle size, dipole moment, and
solubility etc. play important roles.35
membrane phase. Further studies are aimed for optimizing
polymer design with better performance and minimum content
of 1,3,4-oxadiazole. In addition, complete optimization of cross-
linking extent for this water borne polymer is necessary for
designing a best membrane with excellent performance, stability
and durability.
Acknowledgements
Authors are thankful to Mr. Sourish Bhattacharya for his help
during course of investigations. We acknowledge the Analytical
Science Division, CSMCRI, Bhavnagar for instrumental
support. Financial assistance received from the Department of
Science and Technology, New Delhi (Govt. of India), by spon-
soring project no. SR/S1/PC/06/2008 is gratefully acknowledged.
Authors also thank the referees for their valuable comments.
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This journal is ª The Royal Society of Chemistry 2012
J. Mater. Chem., 2012, 22, 1834–1844 | 1843