Research On TiO₂ As Matrix To Analysis Of Sulfonamides By MALDI-TOF MS

MALDI-TOF MS is a kind of soft ionization technique for biology.Since 1980s,it has been used in many kinds of biomacromolecule.But it is still difficult to quantify small molecules owning to the existence of background interference in the low molecules.To improve the reproducibility,stability and sensitivity,finding new matrix and improving crystallizing homogenization have drawn special attention of researchers.As a common drug in animal farming,sulfonamides have been used extensively as broad-spectrum antibiotics.However,sulfonamides might lead to disturbance of urination and hematopoiesis,even causing drug resistance and high risk of food safety when residual happens in the food chain.Thus,it is meaningful to detect sulfonamides accurately and rapidly.In this study,nano Ti02 is used as a novel MALDI-TOF matrix to the analyzing of sulfonamides.Compared with the conventional matrix,nano TiO2 display its advantages used as inorganic matrix.By the optimizations of influencing factors,such as target type,dispersants and the ratio between matrix and dispersant,the type of nano TiO2,sample preparation,laser energy and MS mode,following results are obtained.The linearity range,LOD and LOQ of Sulfameter,Sulfamethazine,Sulfamethoxazole and Sulfadiazine are 10?200 pg/L,5 ?g/L and 10 pg/L with R2 of 0.9915,0.9891,0.9976 and 0.9779 respectively.The linearity range,LOD and LOQ of Sulfamethizole and Sulfisoxazole are 20?200 ?g/L,10 ?g/L and 20 ?g/L with R2 of 0.9722 and 0.9995 respectively.The RSDs are all lower than 13.75%.Additionally,in the test of honey sample,the blank sample is ND.The recovery rate are between 70.01?100.78%in the standard recovery experiment.The RSD are between 3.32%?11.62%.Therefore,this new matrix can be used in MALDI-TOF MS detection of sulfanilamides.