A job for quantum dots: use of a smartphone and 3D-printed accessory for all-in-one excitation and imaging of photoluminescence


Point-of-care (POC) diagnostic technologies are needed to improve global health and smartphones are a prospective platform for these technologies. While many fluorescence or photoluminescence-based smartphone assays have been reported in the literature, common shortcomings are the requirement of an excitation light source external to the smartphone and complicated integration of that excitation source with the smartphone. Here, we show that the photographic flash associated with the smartphone camera can be utilized to enable all-in-one excitation and imaging of photoluminescence (PL), thus eliminating the need for an excitation light source external to the smartphone. A simple and low-cost 3D-printed accessory was designed to create a dark environment and direct excitation light from the smartphone flash onto a sample. Multiple colors and compositions of semiconductor quantum dot (QD) were evaluated as photoluminescent materials for all-in-one smartphone excitation and imaging of PL, and these were compared with fluorescein and R-phycoerythrin (R-PE), which are widely utilized molecular and protein materials for fluorescence-based bioanalysis. The QDs were found to exhibit much better brightness and have the best potential for two-color detection. A model protein binding assay with a sub-microgram per milliliter detection limit and a Förster resonance energy transfer (FRET) assay for proteolytic activity were demonstrated, including imaging with serum as a sample matrix. In addition, FRET within tandem conjugates of a QD donor and fluorescent dye acceptor enabled smartphone detection of dye fluorescence that was otherwise unobservable without the QD to enhance its brightness. The ideal properties of photoluminescent materials for all-in-one smartphone excitation and imaging are discussed in the context of several different materials, where QDs appear to be the best overall material for this application.

Bioanalytical assays with a smartphone and 3D-printed accessory for imaging photoluminescence from quantum dots

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8


  1. 1.

    Dhalla I. Canada’s health care system and the sustainability paradox. Can Med Assoc J. 2007;177:51–3.

  2. 2.

    Pentecost MJ. Health care in America: sustainable path or collision course? J Am Coll Radiol. 2005;2:114–7.

  3. 3.

    Yager P, Domingo GJ, Gerdes J. Point-of-care diagnostics for global health. Annu Rev Biomed Eng. 2008;10:107–44.

  4. 4.

    Martinez AW, Phillips ST, Whitesides GM, Carrilho E. Diagnostics for the developingworld: microfluidic paper-based analytical devices. Anal Chem. 2010;82:3–10.

  5. 5.

    Petryayeva E, Algar WR. Toward point-of-care diagnostics with consumer electronicdevices: the expanding role of nanoparticles. RSC Adv. 2015;5:22256–82.

  6. 6.

    Vashist SK, Mudanyali O, Schneider EM, Zengerle R, Ozcan A. Cellphone-baseddevices for bioanalytical sciences. Anal Bioanal Chem. 2014;406:3263–77.

  7. 7.

    Erickson D, O'Dell D, Jiang L, Oncescu V, Gumus A, Lee S, et al. Smartphone technology can be transformative to deployment of lab-on-chip diagnostics. Lab Chip. 2014;14:3159–64.

  8. 8.

    Li B, Li L, Guan A, Dong Q, Ruan K, Hu R, et al. A smartphone controlled handheldmicrofluidic liquid handling system. Lab Chip. 2014;14:4085–92.

  9. 9.

    Laksanasopin T, Guo TW, Nayak S, Sridhara AA, Xie S, Olowookere OO, et al. A smartphone dongle for diagnosis of infectious diseases at the point of care. Sci Transl Med. 2015;7:273re271.

  10. 10.

    Mancuso M, Cesarman E, Erickson D. Detection of Kaposi’s sarcoma associatedherpesvirus nucleic acids using a smartphone accessory. Lab Chip. 2014;14:3809–16.

  11. 11.

    Nemiroski A, Christodouleas DC, Hennek JW, Kumar AA, Maxwell EJ, Fernández-Abedul MT, et al. Universal mobile electrochemical detector designed for use in resource-limited applications. Proc Natl Acad Sci USA. 2014;111:11984–9.

  12. 12.

    Long KD, Yu H, Cunningham BT. Smartphone instrument for portable enzyme-linkedimmunosorbent assays. Biomed Opt Exp. 2014;5:3792–806.

  13. 13.

    Berg B, Cortazar B, Tseng D, Ozkan H, Feng S, Wei Q, et al. Cellphone-based hand-held microplate reader for point-of-care testing of enzyme-linked immunosorbent assays. ACS Nano. 2015;9:7857–66.

  14. 14.

    Nie H, Wang W, Li W, Nie Z, Yao S. A colorimetric and smartphone readable methodfor uracil-DNA glycosylase detection based on the target-triggered formation of G-quadruplex. Analyst. 2015;140:2771–7.

  15. 15.

    Guo J, Wong JXH, Cui C, Li X, Yu H-Z. A smartphone-readable barcode assay for thedetection and quantitation of pesticide residues. Analyst. 2015;140:5518–25.

  16. 16.

    Veigas B, Jacob JM, Costa MN, Santos DS, Viveiros M, Inacio J, et al. Gold on paper-paper platform for Au-nanoprobe TB detection. Lab Chip. 2012;12:4802–8.

  17. 17.

    Wong JXH, Li X, Liu FSF, Yu H-Z. Direct Reading of bona fide barcode assays fordiagnostics with smartphone apps. Sci Rep. 2015;5:11727.

  18. 18.

    Lee S, Oncescu V, Mancuso M, Mehta S, Erickson D. A smartphone platform for thequantification of vitamin D levels. Lab Chip. 2014;14:1437–42.

  19. 19.

    Gallegos D, Long KD, Yu H, Clark PP, Lin Y, George S, et al. Label-free biodetection using a smartphone. Lab Chip. 2013;13:2124–32.

  20. 20.

    Im H, Castro CM, Shao H, Liong M, Song J, Pathania D, et al. Digital diffraction analysis enables low-cost molecular diagnostics on a smartphone. Proc Natl Acad Sci U S A. 2015;112:5613–8.

  21. 21.

    Rajendran VK, Bakthavathsalam P, Ali BMJ. Smartphone based bacterial detectionusing biofunctionalized fluorescent nanoparticles. Microchim Acta. 2014;181:1815–21.

  22. 22.

    Zhu HY, Sikora U, Ozcan A. Quantum dot enabled detection of Escherichia coli using acell-phone. Analyst. 2012;137:2541–4.

  23. 23.

    Fronczek CF, Park TS, Harshman DK, Nicolini AM, Yoon J-Y. Paper microfluidicextraction and direct smartphone-based identification of pathogenic nucleic acids from field andclinical samples. RSC Adv. 2014;4:11103–10.

  24. 24.

    Noor MO, Hrovat D, Moazami-Goudarzi M, Espie GS, Krull UJ. Ratiometric fluorescence transduction by hybridization after isothermal amplification for determination of zeptomole quantities of oligonucleotide biomarkers with a paper-based platform and camerabased detection. Anal Chim Acta. 2015;885:156–65.

  25. 25.

    Noor MO, Krull UJ. Camera-based ratiometric fluorescence transduction of nucleicacid hybridization with reagentless signal amplification on a paper-based platform using immobilized quantum dots as donors. Anal Chem. 2014;86:10331–9.

  26. 26.

    Jiang L, Mancuso M, Lu Z, Akar G, Cesarman E, Erickson D. Solar thermal polymerasechain reaction for smartphone-assisted molecular diagnostics. Sci Rep. 2014;4:4137.

  27. 27.

    Shu B, Zhang C, Xing D. A handheld flow genetic analysis system (FGAS): towardsrapid, sensitive, quantitative and multiplex molecular diagnosis at the point-of-care level. Lab Chip. 2015;15:2597–605.

  28. 28.

    Hempstead J, Jones DP, Ziouche A, Cramer GM, Rizvi I, Arnason S, et al. Low-cost photodynamic therapy devices for global health settings: characterization of battery powered LED performance and smartphone imaging in 3D tumor models. Sci Rep. 2015;5:10093.

  29. 29.

    Koydemir HC, Gorocs Z, Tseng D, Cortazar B, Feng S, Chan RYL, et al. Rapid imaging, detection and quantification of Giardia lamblia cysts using mobile-phone based fluorescent microscopy and machine learning. Lab Chip. 2015;15:1284–93.

  30. 30.

    Wei Q, Luo W, Chiang S, Kappel T, Mejia C, Tseng D, et al. Imaging and sizing of single DNA molecules on a mobile phone. ACS Nano. 2014;8:12725–33.

  31. 31.

    Petryayeva E, Algar WR. Multiplexed homogeneous assays of proteolytic activityusing a smartphone and quantum dots. Anal Chem. 2014;86:3195–202.

  32. 32.

    Petryayeva E, Algar WR. Proteolytic assays on quantum-dot-modified papersubstrates using simple optical readout platforms. Anal Chem. 2013;85:8817–25.

  33. 33.

    Petryayeva E, Algar WR. Single-step bioassays in serum and whole blood with asmartphone, quantum dots and paper-in-PDMS chips. Analyst. 2015;140:4037–45.

  34. 34.

    Balsam J, Bruck HA, Rasooly A. Capillary array waveguide amplified fluorescence detector for mHealth. Sens Actuators B. 2013;186:711–7.

  35. 35.

    Hossain MA, Canning J, Ast S, Cook K, Rutledge PJ, Jamalipour A. Combined “dual”absorption and fluorescence smartphone spectrometers. Opt Lett. 2015;40:1737–40.

  36. 36.

    Yu H, Tan Y, Cunningham BT. Smartphone fluorescence spectroscopy. Anal Chem. 2014;86:8805–13.

  37. 37.

    Michalet X, Pinaud FF, Bentolila LA, Tsay JM, Doose S, Li JJ, et al. Quantum dots for live cells, in vivo imaging, and diagnostics. Science. 2005;307:538–44.

  38. 38.

    Medintz IL, Uyeda HT, Goldman ER, Mattoussi H. Quantum dot bioconjugates forimaging, labelling and sensing. Nat Mater. 2005;4:435–46.

  39. 39.

    Chan WCW, Maxwell DJ, Gao XH, Bailey RE, Han MY, Nie SM. Luminescent quantum dots for multiplexed biological detection and imaging. Curr Opin Biotechnol. 2002;13:40–6.

  40. 40.

    Gill R, Zayats M, Willner I. Semiconductor quantum dots for bioanalysis. Angew Chem Int Ed. 2008;47:7602–25.

  41. 41.

    Wegner KD, Hildebrandt N. Quantum dots: bright and versatile in vitro and in vivofluorescence imaging biosensors. Chem Soc Rev. 2015;44:4792–834.

  42. 42.

    Petryayeva E, Algar WR, Medintz IL. Quantum dots in bioanalysis: a review of applications across various platforms for fluorescence spectroscopy and imaging. Appl Spectrosc. 2013;67:215–52.

  43. 43.

    Li JJ, Wang YA, Guo WZ, Keay JC, Mishima TD, Johnson MB, et al. Large-scale synthesis of nearly monodisperse CdSe/CdS core/shell nanocrystals using air-stable reagents via successive ion layer adsorption and reaction. J Am Chem Soc. 2003;125:12567–75.

  44. 44.

    Yu WW, Peng X. Formation of high-quality CdS and other II-VI semiconductor nanocrystals in noncoordinating solvents: tunable reactivity of monomers. Angew Chem Int Ed. 2002;41:2368–71.

  45. 45.

    Sapsford KE, Pons T, Medintz IL, Higashiya S, Brunel FM, Dawson PE, et al. Kinetics of metal-affinity driven self-assembly between proteins or peptides and CdSe-ZnS quantum dots. J Phys Chem C. 2007;111:11528–38.

  46. 46.

    Aldeek F, Safi M, Zhan NQ, Palui G, Mattoussi H. Understanding the self-assembly ofproteins onto gold nanoparticles and quantum dots driven by metal-histidine coordination. ACS Nano. 2013;7:10197–210.

  47. 47.

    Umberger JQ, LaMer VK. The kinetics of diffussion controlled molecular and ionicreactions in solution as determined by measurements of the quenching of fluorescence. J Am Chem Soc. 1945;67:1099–109.

  48. 48.

    Oi VT, Glazer AN, Stryer L. Fluorescent phycobiliprotein conjugates for analyses ofcells and molecules. J Cell Biol. 1982;93:981–6.

  49. 49.

    Pommier AJC, Shaw R, Spencer SKM, Morgan SR, Hoff PM, Robertson JD, et al. Serum protein profiling reveals baseline and pharmacodynamic biomarker signatures associated with clinical outcome in mCRC patients treated with chemotherapy ± cediranib. British J Cancer. 2014;111:1590–604.

  50. 50.

    Algar WR, Tavares AJ, Krull UJ. Beyond labels: A review of the application of quantum dots as integrated components of assays, bioprobes, and biosensors utilizing optical transduction. Anal Chim Acta. 2010;673:1–12.

  51. 51.

    Pansare V, Hejazi S, Faenza W, Prud'homme RK. Review of long-wavelength optical and NIR imaging materials: contrast agents, fluorophors and multifunctional nano carriers. Chem Mater. 2012;24:812–27.

  52. 52.

    Szollosi J, Damjanovich S, Matyus L. Cytometry. Application of fluorescence resonance energy transfer in the clinical laboratory: routine and research. 1998;34:159–79.

  53. 53.

    Brown M, Wittwer C. Flow cytometry: principles and clinical applications in hematology. Clin Chem. 2000;46:1221–9.

  54. 54.

    Sjoback R, Nygren J, Kubista M. Absorption and fluorescence properties of fluorescein. Spectrochim Acta A. 1995;51:L7–L21.

  55. 55.

    Batard P, Szollosi J, Luescher I, Cerottini JC, MacDonald R, Romero P. Use of Phycoerythrin and Allophycocyanin for fluorscence resonance energy transfer analyzed by flow cytometry: advantages and limitations. Cytometry. 2002;48:97–105.

  56. 56.

    ThermoFisher Scientific (2015) R-phycoerythrin (R-PE). http://www.thermofisher.com/ca/en/home/life-science/cell-analysis/fluorophores/r-phycoerythrin.html. Accessed 17 Oct 2015.

  57. 57.

    ThermoFisher Scientific (2015) Fluorescein (FITC). http://www.thermofisher.com/ca/en/home/life-science/cell-analysis/fluorophores/fluorescein.html. Accessed 17 Oct 2015.

  58. 58.

    Song L, Hennink EJ, Young IT, Tanke HJ. Photobleaching kinetics of fluorescein in quantitative fluorescence microscopy. Biophys J. 1995;68:2588–600.

  59. 59.

    Bünzli JCG. On the design of highly luminescent lanthanide complexes. Coord Chem Rev. 2015;293–294:19–47.

  60. 60.

    Park YI, Lee KT, Suh YD, Hyeon T. Upconverting nanoparticles: a versatile platform for wide-field two-photon microscopy and multi-modal in vivo imaging. Chem Soc Rev. 2015;44:1302–17.

  61. 61.

    Wang F, Liu X. Recent advances in the chemistry of lanthanide-doped upconversion nanocrystals. Chem Soc Rev. 2009;38:976–89.

  62. 62.

    Chen LY, Wang CW, Yuan Z, Chang HT. Fluorescent gold nanoclusters: recent advances in sensing and imaging. Anal Chem. 2015;87:216–29.

  63. 63.

    Yu P, Wen X, Toh YR, Ma X, Tang J. Fluorescent metallic nanoclusters: electron dynamics, structure, and applications. Part Part Syst Charact. 2015;32:142–63.

  64. 64.

    Luo PG, Yang F, Yang ST, Sonkar SK, Yang L, Broglie JJ, et al. Carbonbased quantum dots for fluorescence imaging of cells and tissues. RSC Adv. 2014;4:10791–807.

  65. 65.

    Yan J, Estévez MC, Smith JE, Wang K, He X, Wang L, et al. Dye-doped nanoparticles for bioanalysis. Nano Today. 2007;2:44–50.

  66. 66.

    Burns A, Ow H, Wiesner U. Fluorescent core-shell silica nanoparticles: towards “lab ona particle” architectures for nanobiotechnology. Chem Soc Rev. 2006;35:1028–42.

  67. 67.

    Massey M, Wu M, Conroy EM, Algar WR. Mind your P’s and Q’s: the coming of age ofsemiconducting polymer dots and semiconductor quantum dots in biological applications. Curr Opin Biotechnol. 2015;34:30–40.

  68. 68.

    Wu CF, Chiu DT. Highly fluorescent semiconductor polymer dots for biology andmedicine. Angew Chem Int Ed. 2013;52:3086–109.

Download references


EP is grateful to the Natural Sciences and Engineering Research Council of Canada (NSERC) for a postgraduate scholarship and to the University of British Columbia (UBC) for a 4YF fellowship. The authors thank the Canada Foundation for Innovation (CFI), British Columbia Knowledge Development Fund (BCKDF), and NSERC for support of this research. WRA is also grateful for a Canada Research Chair (Tier 2) and a Michael Smith Foundation for Health Research Scholar Award. The authors thank Pritesh Padhiar in the UBC Department of Chemistry Mechanical Engineering Shop for assistance with 3D printing, and Erin M. Conroy for providing the A610-labeled peptide.

Author information



Corresponding author

Correspondence to W. Russ Algar.

Ethics declarations

Conflict of interest

The authors declare no conflict of interest.

Additional information

Published in the topical collection featuring Young Investigators in Analytical and Bioanalytical Science with guest editors S. Daunert, A. Baeumner, S. Deo, J. Ruiz Encinar, and L. Zhang.

Electronic supplementary material

Below is the link to the electronic supplementary material.


(PDF 4452 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Petryayeva, E., Algar, W.R. A job for quantum dots: use of a smartphone and 3D-printed accessory for all-in-one excitation and imaging of photoluminescence. Anal Bioanal Chem 408, 2913–2925 (2016). https://doi.org/10.1007/s00216-015-9300-3

Download citation


  • Point-of-care diagnostics
  • Quantum dots
  • Fluorescence
  • FRET
  • Smartphone
  • 3D printing