Vitamin C derivatives as new coreactants for tris(2,2'-bipyridine)ruthenium(II) electrochemiluminescence

Vitamin C derivatives (VCDs) have been widely used as the alternative and stable sources of vitamin C, and accordingly exhibit many new applications, such as anti-tumor and central nervous system drug delivery. In this study, their Ru(bpy)(3)(2+) electrochemiluminescence (ECL) properties have been investigated for the first time using well-known ascorbyl phosphate and ascorbyl palmitate as representative VCDs. Ascorbyl phosphate and ascorbyl palmitate are VCDs with different substituted positions. Both of them increase Ru(bpy)(3)(2+) ECL, indicating that other VCDs may also enhance Ru(bpy)(3)(2+) ECL signal. The calibration plot for ascorbyl phosphate is linear from 3×10(-6) to 1.0×10(-3) M with a detection limit of 1.4×10(-6) M at a signal-to-noise ratio of 3. The relative standard deviation is 3.6% for six replicate measurements of 0.01mM ascorbyl 2-phosphate solution. The proposed method is about one order of magnitude more sensitive than electrochemical and UV-vis methods for the determination of ascorbyl phosphate, and is used successfully for the determination of ascorbyl phosphate in whitening and moisturising body wash.