LAUSR

Abstract Mercaptosuccinic acid-capped CdTe quantum dots were successfully fabricated as a simple synthesized and sensitive fluorescence sensor for tandem determination of mitoxantrone and ribonucleic acid and also monitoring their interaction. Due to the adsorption of positively-charged mitoxantrone on the surface of negatively-charged quantum dots through electrostatic interactions, the fluorescence intensity of mercaptosuccinic acid-capped CdTe quantum dots can be effectively quenched by mitoxantrone. Determination of mitoxantrone was also done through the quenching process, in the range of 0.0675–0.337 µM with LOD of 0.025 µM. Total ribonucleic acid was extracted by AccuZol™ reagent from liver tissue of rat. The concentration of ribonucleic acid was determined 5–6 µg/µL at 260 nm by spectrophotometry (NanoDrop). The 28S and 18S bands of ribosomal ribonucleic acid were obviously revealed on agarose gel electrophoresis which confirmed quality of extracted ribonucleic acid. Nucleic acid purity was monitored by 260/280 nm wavelength absorbance ratio. The ratio was1.97±0.01. After addition of ribonucleic acid to mitoxantrone–quantum dots solution, mitoxantrone mainly bound to the uracil (C˭O) and adenine (C˭N) sites of ribonucleic acid. This complex which was formed between mitoxantrone and ribonucleic acid, prevented more interactions between quantum dots and anticancer drug resulted in enhancing of fluorescence intensity. Thus, the ribonucleic acid determination in the range of 0.3–2.5 ng/µL was based on the abovementioned fluorescence enhancing process with detection limit of 0.1 ng/µL. The proposed method was utilized for the determination of mitoxantrone and ribonucleic acid in the human serum with recovery ranged from 70% to 110% with relative standard deviations of 3.8–10%.