Ultrasensitive detection of phenolphthalein in slimming products by gold-based immunochromatographic paper

An anti-phenolphthalein monoclonal antibody (mAb) was prepared based on the N,N '-Carbonyldiimidazole (CDI) method through phenolphthalein conjugated with proteins. Indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and colloidal gold-based immunochromatographic assay (ICA) methods were used to determine phenolphthalein in slimming products. A standard curve was established, and the IC50 and limit of detection of ic-ELISA were 0.95 and 0.10 ng/mL with a linear detection range of 0.27-3.37 ng/mL. The developed ICA was used to detect phenolphthalein in tablets, capsules, and slimming tea samples with visual limit of detection values of 10 mu g/kg, and cut-off values of 200 mu g/kg. The results indicated that these two methods could be used to quickly detect phenolphthalein in slimming products.

Automated summary

An antibody and two detection methods (ic-ELISA and ICA) were developed for the detection of phenolphthalein in slimming products. These methods showed high sensitivity and a wide detection range, enabling rapid and accurate detection of phenolphthalein.