Neotame is an artificial sweetener with increasing consumption in recent years, excessive intake of it may bring potential health risk. In this work, a rapid method was developed to detect neotame in instant grain beverages, which was based on surface-enhanced Raman scattering (SERS) technique and filter paper-based silver nanoparticles (AgNPs@FP) substrates. The designed substrate exhibits good SERS activity with an enhancement factor of 10⁵ because of the synergistic effect of the concentrated silver nanoparticles and filter paper. Meanwhile, the stability and repeatability of this fabricated substrate have been investigated with the relative standard deviation of 6.1%. In addition, it shows an excellent linear relationship (R ² = 0.997) between the SERS signal and the logarithm concentration of neotame with a wide concentration range (0.05–5 g/kg) in the quantitative analysis. The limit of detection of neotame can be as low as 0.01 g/kg in instant grain beverages, which is below the maximum allowable addition level for neotame in instant grain beverages set in China (GB2760-2014, 0.16 g/kg). The proposed method has great potential for the identification and quantification of neotame in food safety applications with high sensitivity.

References

1. 1)
  - 16. Mekonnen, M.L., Chen, C.H., Su, W.N., et al: ‘3d-functionalized shell isolated Ag nanocubes on a miniaturized flexible platform for sensitive and selective SERS detection of small molecules’, Microchem J., 2018, 142, pp. 305–312 (doi: 10.1016/j.microc.2018.06.039).
2. 2)
  - 2. Kumari, A., Arora, S., Singh, A.K., et al: ‘Development of an analytical method for estimation of neotame in cake and ice cream’, Lwt- Food Sci. Technol., 2016, 70, pp. 142–147 (doi: 10.1016/j.lwt.2016.02.045).
3. 3)
  - 27. Han, C., Yao, Y., Wang, W., et al: ‘Rapid and sensitive detection of sodium saccharin in soft drinks by silver nanorod array SERS substrates’, Sens. Actuators B, Chem., 2017, 251, pp. 272–279 (doi: 10.1016/j.snb.2017.05.051).
4. 4)
  - 22. Lin, B., Kannan, P., Qiu, B., et al: ‘On-spot surface enhanced Raman scattering detection of aflatoxin B1 in peanut extracts using gold nanobipyramids evenly trapped into the AAO nanoholes’, Food Chem., 2020, 307, p. 125528 (doi: 10.1016/j.foodchem.2019.125528).
5. 5)
  - 6. Yang, D., Chen, B.: ‘Determination of neotame in beverages, cakes and preserved fruits by column-switching high-performance liquid chromatography’, Food Addit. Contam., 2010, 27, (9), pp. 1221–1225 (doi: 10.1080/19440049.2010.487875).
6. 6)
  - 29. Shi, Y., Liu, W., Chen, C.: ‘Two-step centrifugation method for subpicomolar surface-enhanced Raman scattering detection’, Anal. Chem., 2016, 88, (9), pp. 5009–5015 (doi: 10.1021/acs.analchem.6b01194).
7. 7)
  - 9. Chen, M., Luo, W., Liu, Q., et al: ‘Simultaneous in situ extraction and fabrication of surface-enhanced Raman scattering substrate for reliable detection of thiram residue’, Anal. Chem., 2018, 90, (22), pp. 13647–13654 (doi: 10.1021/acs.analchem.8b03940).
8. 8)
  - 13. Liu, K., Bai, Y., Zhang, L., et al: ‘Porous Au–Ag nanospheres with high-density and highly accessible hotspots for SERS analysis’, Nano Lett., 2016, 16, (6), pp. 3675–3681 (doi: 10.1021/acs.nanolett.6b00868).
9. 9)
  - 20. Lee, C.H., Hankus, M.E., Tian, L., et al: ‘Highly sensitive surface enhanced Raman scattering substrates based on filter paper loaded with plasmonic nanostructures’, Anal. Chem., 2011, 83, (23), pp. 8953–8958 (doi: 10.1021/ac2016882).
10. 10)
  - 1. Nofre, C., Tinti, J.M.: ‘Neotame: discovery, properties, utility’, Food Chem., 2000, 69, (3), pp. 245–257 (doi: 10.1016/S0308-8146(99)00254-X).
11. 11)
  - 15. Buyukgoz, G.G., Bozkurt, A.G., Akgul, N.B., et al: ‘Spectroscopic detection of aspartame in soft drinks by surface-enhanced Raman spectroscopy’, Eur. Food Res. Technol., 2015, 240, (3), pp. 567–575 (doi: 10.1007/s00217-014-2357-y).
12. 12)
  - 4. Bathinapatla, A., Kanchi, S., Singh, P., et al: ‘Determination of neotame by high-performance capillary electrophoresis using β-cyclodextrin as a chiral selector’, Anal. Lett., 2014, 47, (17), pp. 2795–2812 (doi: 10.1080/00032719.2014.924008).
13. 13)
  - 14. Zheng, C., Zhang, L., Wang, F., et al: ‘Silver nanoparticles/activated carbon composite as a facile SERS substrate for highly sensitive detection of endogenous formaldehyde in human urine by catalytic reaction’, Talanta, 2018, 188, pp. 630–636 (doi: 10.1016/j.talanta.2018.06.040).
14. 14)
  - 26. Jain, R., Ahuja, B., Sharma, B.: ‘Density-functional thermochemistry. III. The role of exact exchange’, Indian J. Pure Appl. Phys., 2004, 42, pp. 43–48.
15. 15)
  - 28. Khlebtsov, B.N., Khanadeev, V.A., Panfilova, E.V., et al: ‘Gold nanoisland films as reproducible SERS substrates for highly sensitive detection of fungicides’, ACS Appl. Mater. Interfaces, 2015, 7, (12), pp. 6518–6529 (doi: 10.1021/acsami.5b01652).
16. 16)
  - 5. Wasik, A., McCourt, J., Buchgraber, M.: ‘Simultaneous determination of nine intense sweeteners in foodstuffs by high performance liquid chromatography and evaporative light scattering detection—development and single-laboratory validation’, J. Chromatogr. A, 2007, 1157, (1–2), pp. 187–196 (doi: 10.1016/j.chroma.2007.04.068).
17. 17)
  - 21. Lee, M., Oh, K., Choi, H.K., et al: ‘Subnanomolar sensitivity of filter paper-based SERS sensor for pesticide detection by hydrophobicity change of paper surface’, ACS Sens., 2018, 3, (1), pp. 151–159 (doi: 10.1021/acssensors.7b00782).
18. 18)
  - 11. Qu, W.G., Lu, L.Q., Lin, L., et al: ‘A silver nanoparticle based surface enhanced resonance Raman scattering (SERRS) probe for the ultrasensitive and selective detection of formaldehyde’, Nanoscale, 2012, 4, (23), pp. 7358–7361 (doi: 10.1039/c2nr32079g).
19. 19)
  - 24. Neese, F.: ‘The ORCA program system’, Wiley Interdiscip. Rev.-Comput. Mol. Sci., 2012, 2, (1), pp. 73–78 (doi: 10.1002/wcms.81).
20. 20)
  - 8. Zhang, R., Zhang, Y., Dong, Z., et al: ‘Chemical mapping of a single molecule by plasmon-enhanced Raman scattering’, Nature, 2013, 498, (7452), pp. 82–86 (doi: 10.1038/nature12151).
21. 21)
  - 19. He, S., Xie, W., Fang, S., et al: ‘Silver films coated inverted cone-shaped nanopore array anodic aluminum oxide membranes for SERS analysis of trace molecular orientation’, Appl. Surf. Sci., 2019, 488, pp. 707–713 (doi: 10.1016/j.apsusc.2019.05.298).
22. 22)
  - 12. Yan, R., Wang, Z., Zhou, J., et al: ‘Gold nanoparticle enriched by Q sepharose spheres for chemical reaction tandem SERS detection of malondialdehyde’, Sens. Actuators B, Chem., 2019, 281, pp. 123–130 (doi: 10.1016/j.snb.2018.10.078).
23. 23)
  - 18. Roy, A., Chini, T.K., Satpati, B.: ‘A simple method of growing endotaxial silver nanostructures on silicon for applications in surface enhanced Raman scattering (SERS)’, Appl. Surf. Sci., 2020, 501, p. 144225 (doi: 10.1016/j.apsusc.2019.144225).
24. 24)
  - 25. Neese, F.: ‘Software update: the ORCA program system, version 4.0’, Wiley Interdiscip. Rev.-Comput. Mol. Sci., 2018, 8, (1), p. e1327, doi: 10.1002/wcms.1327.
25. 25)
  - 17. Kolobkova, E., Kuznetsova, M.S., Nikonorov, N.: ‘Ag/Na Ion exchange in fluorophosphate glasses and formation of Ag nanoparticles in the bulk and on the surface of the glass’, ACS Appl. Nano Mater., 2019, 2, (11), pp. 6928–6938 (doi: 10.1021/acsanm.9b01419).
26. 26)
  - 10. Lv, Z.Y., Mei, L.P., Chen, W.Y., et al: ‘Shaped-controlled electrosynthesis of gold nanodendrites for highly selective and sensitive SERS detection of formaldehyde’, Sens. Actuators B, Chem., 2014, 201, pp. 92–99 (doi: 10.1016/j.snb.2014.04.092).
27. 27)
  - 23. Lee, P., Meisel, D.: ‘Adsorption and surface-enhanced Raman of dyes on silver and gold sols’, J. Phys. Chem., 1982, 86, (17), pp. 3391–3395 (doi: 10.1021/j100214a025).
28. 28)
  - 3. Hu, F., Xu, L., Luan, F., et al: ‘Determination of neotame in non-alcoholic beverage by capillary zone electrophoresis’, J. Sci. Food Agric., 2013, 93, (13), pp. 3334–3338 (doi: 10.1002/jsfa.6181).
29. 29)
  - 7. Lim, H.S., Park, S.K., Kwak, I.S., et al: ‘HPLC-MS/MS analysis of 9 artificial sweeteners in imported foods’, Food Sci. Biotechnol., 2013, 22, (1), pp. 233–240 (doi: 10.1007/s10068-013-0072-2).

Rapid and sensitive detection of neotame in instant grain beverages by paper-based silver nanoparticles substrates

References

Related content