Fabrication of a new SPME fiber based on Polyacrylic acid/ MIL-88(Fe)-NH2 composite as a self-healing coating for the analysis of breast cancer biomarkers in the urine sample

Analysis of cancer biomarkers in the body fluids is a new method for early detection of illness. However, due to the complex matrices of samples, the application of a pre-treatment method is unavoidable before the final analysis by gas chromatography (GC). Solid-phase microextraction (SPME) is a simple and, promising pre-concentration and separation method that its coatings are modified with different materials on the fibers. A new innovative self-healing polyacrylic acid PAA/MIL-88(Fe)-NH2 composite was synthesized as an SPME coating. The parameters including pH, crosslinker, and MIL-88(Fe)-NH2 content were optimized to formulate the composite. The prepared fiber was used to extract 2-pentanone, 2-heptanone, ethyl propionate, p-xylene, 1,2,4-trimethylbenzene, and o-cresol as a biomarker in breast cancer from urine samples. The prepared PAA/MIL-88(Fe)-NH2 SPME fibers demonstrate excellent repeatability (relative standard deviation (RSD%)< 3.4%) and satisfactory reproducibility (RSD%<6.9%). The central composite design method was applied for the optimization of extraction parameters. Under the optimum conditions, linear dynamic ranges for biomarkers were in the acceptable range with correlation coefficients higher than 0.98. The detection limits of them were less down 0.0016 µg L−1. Self-healing ability of fiber coating increased useful lifetime (about 120 times extraction with one fiber) as well as accuracy, reproducibility, and recovery of fibers.