Technique Analytes Matrix(% Recovery) System Eluent PF Detection limit (μg L−1) R.S.D (%) Optimum operating condition Reference
FAAS Cu, Fe, Pb, Mn, Zn,Cd, Ni, Bi, Cr   Co-DEDTC 1.0 mL conc. HNO3 225 4–64 <7 pH: [32]
Amount of carrier element (mg):
Amount of chelating agent(mg):
Sample volume (mL):
FAAS Pb, Cd, Cr, Ni, Mn Water(96 – 98) Cu- DBDTC 0.5 mL conc. HNO3 50 0.34–0.87 <10 pH:                                                  9 [33]
Amount of carrier element (mg):    1
Amount of chelating agent(mg):     10
Sample volume (mL):                     25
FAAS Cd, Cu, Pb Water( 88.6 -103.5) Bi(III)4-MPDTC 1 mL conc. HNO3 200 0.18-0.50 <10 pH:                                                5 [26]
Amount of carrier element (mg): 4
Amount of chelating agent(mg): 400
Sample volume (mL):                  250
FAAS Ni, Cr, Mn, Pb, Zn Water (96.8-100)        Sediment (97.3-99.2) Cu-cHMDTC 0.5 mL conc. HNO3 10 0.003-0.10 <17 pH:                                                9 [28]
Amount of carrier element (mg): 1
Amount of chelating agent(mg): 10
Sample volume (mL):                 25
FAAS Ni Water (89.5 ± 1.3)
Sediment (90.2 ± 0.3)
Cu-MBDTC 1.0 mL conc. HNO3 10 0.003-0.006 < 5 pH:    9 This study
Cr Water (93.2 ± 2.1)
Sediment (87.2 ± 1.1)
Amount of carrier element (mg): 1
Co Water (92.1 ± 2.4)
Sediment (89.0 ± 0.5)
Amount of chelating agent(mg): 10
Mn Water (89.7 ± 0.5)
Sediment (92.7 ± 0.4)
Sample volume (mL):                 10
PF – preconcentration factor, R.S.D – Relative Standard Deviation; DEDTC – diethyldithiocarbamate; DBDTC - dibenzyldithiocarbamate; MPDTC - methylpiperidinedithiocarbamate; MBDTC - methylbutyldithiocarbamate FAAS – Flame atomic absorption spectrometry; cHMDTC - cyclohexylmethyldithiocarbamate
Table 2: Comparison of this study with data from some previous studies on preconcentration–separation of heavy metal ions.