Skip to main content
SpringerLink
Log in

Determination of copper in powdered chocolate samples by slurry-sampling flame atomic-absorption spectrometry

  • Original Paper
  • Published:
Analytical and Bioanalytical Chemistry Aims and scope Submit manuscript

Abstract

Chocolate is a complex sample with a high content of organic compounds and its analysis generally involves digestion procedures that might include the risk of losses and/or contamination. The determination of copper in chocolate is important because copper compounds are extensively used as fungicides in the farming of cocoa. In this paper, a slurry-sampling flame atomic-absorption spectrometric method is proposed for determination of copper in powdered chocolate samples. Optimization was carried out using univariate methodology involving the variables nature and concentration of the acid solution for slurry preparation, sonication time, and sample mass. The recommended conditions include a sample mass of 0.2 g, 2.0 mol L−1 hydrochloric acid solution, and a sonication time of 15 min. The calibration curve was prepared using aqueous copper standards in 2.0 mol L−1 hydrochloric acid. This method allowed determination of copper in chocolate with a detection limit of 0.4 μg g−1 and precision, expressed as relative standard deviation (RSD), of 2.5% (n=10) for a copper content of approximately 30 μg g−1, using a chocolate mass of 0.2 g. The accuracy was confirmed by analyzing the certified reference materials NIST SRM 1568a rice flour and NIES CRM 10-b rice flour. The proposed method was used for determination of copper in three powdered chocolate samples, the copper content of which varied between 26.6 and 31.5 μg g−1. The results showed no significant differences with those obtained after complete digestion, using a t-test for comparison.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Lima JO, dos Santos JK, Pereira JF, de Resende MLV, de Araujo EF, de Queiroz MV (2003) Curr Genet 42:236–240

    CAS  PubMed  Google Scholar 

  2. Surujdeo-Maharaj S, Umaharan P, Butler DR (2004) Plant Dis 88:797–803

    Google Scholar 

  3. Appiah AA, Opoku IY, Akrofi AY (2004) Eur J Plant Pathol 110:983–990

    Article  Google Scholar 

  4. Lima JS (1994) Agric Ecosyst Environ 48:19–25

    Article  CAS  Google Scholar 

  5. Klumpp A, Bauer K, Franz-Gerstein C, de Menezes M (2002) Environ Int 28:165–171

    Article  CAS  PubMed  Google Scholar 

  6. Krauss U, Soberanis W (2002) Biol Control 24:82–89

    Article  Google Scholar 

  7. Hidalgo E, Bateman R, Krauss U, Ten Hoopen M, Martinez A (2003) Eur J Plant Pathol 109:953–961

    Article  Google Scholar 

  8. Kurfürst U (1997) Solid sample analysis—direct and slurry-sampling using ETAAS and ETV-ICP. Springer, Berlin Heidelberg New York

    Google Scholar 

  9. de Moraes Flores EM, Saidelles APF, de Moraes Flores EL, Mesko MF, Pedroso MP, Dressler VL, Bittencourt CF, da Costa AB (2004) Microchem J 77:113–118

    Article  Google Scholar 

  10. Silva MM, Vale MGR, Damin ICF, Welz B, Mandaji M, Fett JP (2003) Anal Bioanal Chem 377:165–172

    Article  CAS  PubMed  Google Scholar 

  11. Butcher DJ (2002) Appl Spectrosc Rev 37:305–319

    Article  CAS  Google Scholar 

  12. Vale MGR, Damin ICF, Klassen A, Silva MM, Welz B, Silva AF, Lepri FG, Borges DLG, Heitmann U (2004) Microchem J 77:131–140

    Article  CAS  Google Scholar 

  13. Aucelio RQ, Doyle A, Pizzorno BS, Tristao MLB, Campos RC (2004) Microchem J 78:21–26

    Article  CAS  Google Scholar 

  14. Amaro JAA, Ferreira SLC (2004) J Anal At Spectrom 19:246–249

    Article  CAS  Google Scholar 

  15. Ebdon L, Foulkes M, Sutton K (1997) J Anal At Spectrom 12:213–229

    Article  CAS  Google Scholar 

  16. Cal-Prieto MJ, Felipe-Sotelo M, Carlosena A, Andrade JM, Lopez-Mahia P, Muniategui S, Prada D (2002) Talanta 56:1–51

    Article  CAS  Google Scholar 

  17. Amin N, Kaneco S, Suzuki T, Ohta K (2003) Microchem J 74:181–186

    Article  CAS  Google Scholar 

  18. Ribeiro AS, Vieira MA, Curtius AJ (2004) Spectrochim Acta B 59:243–253

    Article  Google Scholar 

  19. Maia SM, Pozebon D, Curtius AJ (2003) J Anal At Spectrom 18:330–337

    Article  CAS  Google Scholar 

  20. Matusiewicz H (2003) Appl Spectrosc Rev 38:263–294

    Article  CAS  Google Scholar 

  21. Segade SR, Tyson JF (2003) J Anal At Spectrom 18:268–273

    Article  Google Scholar 

  22. Liva M, Munoz-Olivas R, Camara C (2000) Talanta 51:381–387

    Article  CAS  Google Scholar 

  23. Vieira MA, Ribeiro AS, Curtius AJ (2004) Anal Bioanal Chem 380:570–577

    Article  CAS  PubMed  Google Scholar 

  24. Bautista MA, Sirvent CP, Garcia IL, Cordoba MH (1994) Fresenius J Anal Chem 350:359–364

    Article  CAS  Google Scholar 

  25. LopezGarcia I, SanchezMerlos M, HernandezCordoba M (1996) At Spectrosc 17:107–111

    CAS  Google Scholar 

  26. DeAlmeida MD, Leandro KC, DaCosta CV, Santelli RE, DelaGuardia M (1997) J Anal At Spectrom 12:1235–1238

    Article  CAS  Google Scholar 

  27. Alves FL, Cadore S, Jardim WF, Arruda MAZ (2001) J Braz Chem Soc 12:799–803

    Article  CAS  Google Scholar 

  28. Pereira ER, Berndt H, Arruda MAZ (2002) J Anal At Spectrom 17:1308–1315

    Article  Google Scholar 

  29. Quaresma MCB, Cassella RJ, De LaGuardia M (2004) Talanta 62:807–811

    Article  CAS  Google Scholar 

  30. Ferreira SLC, Lemos VA, Moreira BC, Costa ACS, Santelli RE (2000) Anal Chim Acta 403:259–264

    Article  CAS  Google Scholar 

  31. Ferreira SLC, dos Santos WNL, Lemos VA (2001) Anal Chim Acta 445:145–151

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors are grateful to Fundação de Amparo a Pesquisa do Estado da Bahia (FAPESB), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for providing grants and fellowships and for financial support.

Author information

Authors and Affiliations

  1. Universidade Federal da Bahia, Instituto de Química, Núcleo de Excelência em Química Analítica da Bahia, Campus Universitário de Ondina, Salvador, 40170-290 Bahia, Brasil

    Walter N. L. dos Santos, Erik G. P. da Silva, Marcelo S. Fernandes, Rennan G. O. Araujo, Antônio C. S. Costa & Sèrgio L. C. Ferreira

  2. Universidade Federal da Bahia do Rio Grande do Sul, Instituto de Química, Porto Alegre, 91501-970 Rio Grande do Sul, Brasil

    M. G. R. Vale

Authors
  1. Walter N. L. dos Santos
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Erik G. P. da Silva
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Marcelo S. Fernandes
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Rennan G. O. Araujo
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Antônio C. S. Costa
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. M. G. R. Vale
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Sèrgio L. C. Ferreira
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Sèrgio L. C. Ferreira.

Rights and permissions

Reprints and permissions

About this article

Cite this article

dos Santos, W.N.L., da Silva, E.G.P., Fernandes, M.S. et al. Determination of copper in powdered chocolate samples by slurry-sampling flame atomic-absorption spectrometry. Anal Bioanal Chem 382, 1099–1102 (2005). https://doi.org/10.1007/s00216-005-3252-y

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00216-005-3252-y

Keywords

Search

Navigation