ABSTRACT
Objective To optimize the experiment conditions of surface-enhanced Raman spectroscopy detection of serum fingerprint spectra.Methods Normal human serum was used as the sample and Ag nanoparticles as the active substrate.The enhanced signals of different optimized experiments were obtained , including serum dose(2.5 to 500 μl), incubation time(10 to 30 minutes) temperature(4℃,room temperature and 37℃),and different treatment(extraction and protein removal).Results and Conclusion Serum doses should not exceed 50μl.The ratio should range from 1∶1 to 5∶1, the incubation time is from 10 to 30 minutes, and the incubation temperature from 4℃ to 37℃.The signals of samples directly mixed with an active substrate are stronger than those of samples which are extracted or protein removed .
ABSTRACT
The removal efficiency of the heavy metals Zn, Pb and Cd by the zoosporic fungal species Saprolegnia delica and the terrestrial fungus Trichoderma viride, isolated from polluted water drainages in the Delta of Nile in Egypt, as affected by various ranges of pH values and different temperature degrees,was extensively investigated. The maximum removal efficiency of S. delica for Zn(II) and Cd(II) was obtained at pH 8 and for Pb(II) was at pH 6 whilst the removal efficiency of T. viride was found to be optimum at pH 6 for the three applied heavy metals. Regardless the median lethal doses of the three heavy metals, Zn recorded the highest bioaccumulation potency by S. delica at all pH values except at pH 4, followed by Pb whereas Cd showed the lowest removal potency by the fungal species and vice versa in case of T. viride. The optimum biomass dry weight production by S. delica was found when the fungus was grown in the medium treated with the heavy metal Pb at pH 6, followed by Zn at pH 8 and Cd at pH 8. The optimum biomass dry weight yield by T. viride amended with Zn,Pb and Cd was obtained at pH 6 for the three heavy metals with the maximum value at Zn. The highest yield of biomass dry weight was found when T. viride treated with Cd at all different pH values followed by Pb whilst Zn output was the lowest and this result was reversed in case of S. delica. The maximum removal efficiency and the biomass dry weight production for the three tested heavy metals was obtained at the incubation temperature 20degrees C in case of S. delica while it was 25degrees C for T. viride. Incubation of T. viride at higher temperatures (30degrees C and 35degrees C) enhanced the removal efficiency of Pb and Cd than low temperatures (15degrees C and 20degrees C) and vice versa in case of Zn removal. At all tested incubation temperatures, the maximum yield of biomass dry weight was attained at Zn treatment by the two tested fungal species. The bioaccumulation potency of S. delica for Zn was higher than that for Pb at all temperature degrees of incubation and Cd bioaccumulation was the lowest whereas T. viride showed the highest removal efficiency for Pb followed by Cd and Zn was the minor of the heavy metals.