Reagent Solvent λmax (nm) Concentration range (mg mL-1) ε L mol-1 cm-1 Reference BCG Chloroform 415 1.2–25.0 1.58×104 [24] CCR Chloroform 460 1.5–60.0 9.79×103 [24] chromotrope 2B  Methylene chloride 540 3.3–87.0 1.02×104 [25] chromotrope 2R Methylene chloride 520 3.3–96.0 8.30×103 [25] 3-phenylazo-6-o-carboxyphenylazo-chromotropic acid Methylene chloride 540 5.0–115.0 6.83×103 [25] bis-3,6-(ohydroxyphenylazo)- chromotropic acid Methylene chloride 570 2.5–125.0 5.42×103 [25] bis-3,6-(p-N,N-dimethylphenylazo)-chromotropic acid Methylene chloride 600 8.3–166.7 3.35×103 [25] 3-phenylazo-6-o-hydroxyphenylazo-chromotorpic acid Methylene chloride 575 0.8–15.0 2.32×104 [25] Iodine 1,2-Dichloroethane 366 15–160 3.75×103 [28] TCNQ Acetonitrile 841 15–220 2.58×103 [28] DDQ Methanol 460 20–260 2.41×103 [28] TCNE Acetonitrile 415 10–210 3.05×103 [28] TNF 1,2-Dichloroethane 412 15–240 2.25×103 [28] Chloranilic acid Acetonitrile 529 20–180 3.26×103 [28] Chloranil Acetonitrile 550 28–150 3.42×103 [28] Bromanil Methanol 455 15–170 2.90×103 [28] Congo Red   523 0.2-7.0 mu g/mL   [31] Sudan 11   554 0.2-7.0 mu g/mL   [31] Gentian Violet   569 0.2-7.0 mu g/mL   [31] Methylene blue Aqueous medium 600 Up to 10.6 3.00x104 [40] Ethyl eosin Aqueous medium 520 1.3-3.3 2.44x104 [41] BTB Methylene chloride 415 1- 40 2.01×105 Proposed method BPB Chloroform 410 1- 50 4.44×104 Proposed method EBBR Methylene chloride 510 3- 70 2.40×104 Proposed method

Table 4: Comparative studies between the proposed and previously reported spectrophotometric methods for determination of SILC.