Chemiluminescence Detection Drug Based On Sulfur Quantum Dots

Sulfur is a bioactive element,which is not only one of the indispensable elements to maintain the normal activities of life,but also a low-cost environmental friendly element.In view of the good fluorescence characteristics of sulfur quantum dots,however,the chemiluminescence characteristics of sulfur quantum dots are rarely reported.In this paper,sodium sulfide was used as raw material to directly prepare sulfur quantum dots by air oxidation.Fluorescence spectra,UV-vis absorption spectra,X-ray diffraction spectra(XRD),transmission electron microscopy(TEM),raman spectra(Raman)of the prepared sulfur quantum dots were characterized.A simple synthesis method of sulfur quantum dots was established and the synthesis mechanism was preliminarily discussed.The chemiluminescence properties of sulfur quantum dots were explored by using the sulfur quantum dots as chemiluminescence luminophore.In this study,it was found that hydrogen peroxide can oxidize sulfur quantum dots with weak chemiluminescence emission.Amoxicillin can significantly enhance the chemiluminescence emission of the reaction of hydrogen peroxide with sulfur quantum dots.A simple chemiluminescence analysis method for the detection of amoxicillin was established based on this discover.Under optimized conditions,the concentration of amoxicillin was linearly correlated with chemiluminescence intensity in the range of 1.0×10-8～9.0×10-7 g/mL with a linear equation of I=43.91C+51.26(n=5,r=0.996).The detection limit was 3×10-9,and the relative standard deviation was 3.5%for 11 repeated measurements of 5×10-7g/mL amoxicillin,and the established method was also applied to the detection of amoxicillin samples in capsules with satisfied recovery.Moreover,it is found that potassium ferricyanide can oxidize sulfur quantum dots producing weak chemiluminescence emission in alkaline medium,and methimazole can enhance the chemiluminescence of the reaction between potassium ferricyanide with sulfur quantum dots.Combined with the flow injection technique,a new flow injection-chemiluminescence method for the determination of methimazole was established based on sulfur quantum dots.The concentration of sulfur quantum dots,potassium ferricyanide and sodium hydroxide in alkaline medium were optimized.Under the selected optimization conditions,the chemiluminescence intensity of the system showed a good linear relationship with the concentration of methimazole in the range of 5.0×10-8 g/mL～1.0×10-6 g/mL.The detection limit of the method was 2×10-8 g/mL.The relative standard deviation(RSD)was 2.5%for 11 repeated measurements of the 2×10-7 g/mL methimazole.The content of methimazole solution in urine was also determined using the established method with satisfactory results.In this paper,sulfur quantum dots were prepared by a new simple method based on the oxidation of sodium sulfide by air.For the first time,the sulfur quantum dots were used as chemiluminescence luminophore in chemiluminescence analysis system,and new methods were established for the detection of amoxicillin and methimazole.The new established methods are simple,rapid and sensitive.The new method can provide a new reference for drug analysis,and it lays a theoretical base and provides a feasible reference for the future subsequent development chemiluminescence-paper test of amoxicillin and methimazole.