More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets
Dynabeads are superparamagnetic particles used for the immunomagnetic purification of cells and biomolecules. Post‐capture, however, target identification relies on tedious culturing, fluorescence staining, and/or target amplification. Raman spectroscopy presents a rapid detection alternative, but c...
| Main Authors: | , , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2024
|
| Subjects: | |
| Online Access: | https://hdl.handle.net/1721.1/153554 |
| _version_ | 1811078698459201536 |
|---|---|
| author | Lee, Jongwan McDonald, Marissa Mhlanga, Nikiwe Kang, Jeon Woong Karnik, Rohit Tadesse, Loza F. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Lee, Jongwan McDonald, Marissa Mhlanga, Nikiwe Kang, Jeon Woong Karnik, Rohit Tadesse, Loza F. |
| author_sort | Lee, Jongwan |
| collection | MIT |
| description | Dynabeads are superparamagnetic particles used for the immunomagnetic purification of cells and biomolecules. Post‐capture, however, target identification relies on tedious culturing, fluorescence staining, and/or target amplification. Raman spectroscopy presents a rapid detection alternative, but current implementations target cells themselves with weak Raman signals. We present antibody‐coated Dynabeads as strong Raman reporter labels whose effect can be considered a Raman parallel of immunofluorescent probes. Recent developments in techniques for separating target‐bound Dynabeads from unbound Dynabeads make such an implementation feasible with high specificity. We deploy Dynabeads anti<jats:italic>‐Salmonella</jats:italic> to bind and identify <jats:styled-content style="fixed-case"><jats:italic>Salmonella enterica</jats:italic></jats:styled-content>, a major foodborne pathogen. Dynabeads present major peaks around 1000 and 1600 cm<jats:sup>−1</jats:sup> from aliphatic and aromatic C‐C stretching of the polystyrene coating and near 1350 cm<jats:sup>−1</jats:sup> from the ɣ‐Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> core, confirmed with electron dispersive X‐ray (EDX) imaging. Minor to no contributions are made from the surface antibodies themselves as confirmed by Raman analysis of surface‐activated, antibody‐free beads. Dynabeads' Raman signature can be measured in dry and liquid samples even at single shot ~30 × 30 μm area imaging using 0.5 s, 7‐mW laser acquisition with single and clustered beads providing a 44‐ and 68‐fold larger Raman intensity compared with the signature from cells. Higher polystyrene and iron oxide content in clusters yields larger signal intensity, and conjugation to bacteria strengthens clustering as a bacterium can bind to more than one bead as observed via transmission electron microscopy (TEM). Our findings shed light on the intrinsic Raman reporter nature of Dynabeads. When combined with emerging techniques for the separation of target‐bound Dynabeads from unbound Dynabeads such as using centrifugation through a density media bilayer, they have the potential to demonstrate their dual function for target isolation and detection without tedious staining steps or unique plasmonic substrate engineering, advancing their applications in heterogeneous samples like food, water, and blood. |
| first_indexed | 2024-09-23T11:04:03Z |
| format | Article |
| id | mit-1721.1/153554 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T11:04:03Z |
| publishDate | 2024 |
| publisher | Wiley |
| record_format | dspace |
| spelling | mit-1721.1/1535542024-09-20T19:10:33Z More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets Lee, Jongwan McDonald, Marissa Mhlanga, Nikiwe Kang, Jeon Woong Karnik, Rohit Tadesse, Loza F. Massachusetts Institute of Technology. Department of Mechanical Engineering Harvard University--MIT Division of Health Sciences and Technology Massachusetts Institute of Technology. Spectroscopy Laboratory Ragon Institute of MGH, MIT and Harvard Spectroscopy General Materials Science Dynabeads are superparamagnetic particles used for the immunomagnetic purification of cells and biomolecules. Post‐capture, however, target identification relies on tedious culturing, fluorescence staining, and/or target amplification. Raman spectroscopy presents a rapid detection alternative, but current implementations target cells themselves with weak Raman signals. We present antibody‐coated Dynabeads as strong Raman reporter labels whose effect can be considered a Raman parallel of immunofluorescent probes. Recent developments in techniques for separating target‐bound Dynabeads from unbound Dynabeads make such an implementation feasible with high specificity. We deploy Dynabeads anti<jats:italic>‐Salmonella</jats:italic> to bind and identify <jats:styled-content style="fixed-case"><jats:italic>Salmonella enterica</jats:italic></jats:styled-content>, a major foodborne pathogen. Dynabeads present major peaks around 1000 and 1600 cm<jats:sup>−1</jats:sup> from aliphatic and aromatic C‐C stretching of the polystyrene coating and near 1350 cm<jats:sup>−1</jats:sup> from the ɣ‐Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> core, confirmed with electron dispersive X‐ray (EDX) imaging. Minor to no contributions are made from the surface antibodies themselves as confirmed by Raman analysis of surface‐activated, antibody‐free beads. Dynabeads' Raman signature can be measured in dry and liquid samples even at single shot ~30 × 30 μm area imaging using 0.5 s, 7‐mW laser acquisition with single and clustered beads providing a 44‐ and 68‐fold larger Raman intensity compared with the signature from cells. Higher polystyrene and iron oxide content in clusters yields larger signal intensity, and conjugation to bacteria strengthens clustering as a bacterium can bind to more than one bead as observed via transmission electron microscopy (TEM). Our findings shed light on the intrinsic Raman reporter nature of Dynabeads. When combined with emerging techniques for the separation of target‐bound Dynabeads from unbound Dynabeads such as using centrifugation through a density media bilayer, they have the potential to demonstrate their dual function for target isolation and detection without tedious staining steps or unique plasmonic substrate engineering, advancing their applications in heterogeneous samples like food, water, and blood. 2024-02-22T20:55:13Z 2024-02-22T20:55:13Z 2023-08-29 2024-02-22T17:38:44Z Article http://purl.org/eprint/type/JournalArticle 0377-0486 1097-4555 https://hdl.handle.net/1721.1/153554 J. Lee, M. McDonald, N. Mhlanga, J. W. Kang, R. Karnik, L. F. Tadesse, J Raman Spectrosc 2023, 54(9), 905. en 10.1002/jrs.6584 Journal of Raman Spectroscopy Creative Commons Attribution https://creativecommons.org/licenses/by/4.0/ application/pdf Wiley Wiley |
| spellingShingle | Spectroscopy General Materials Science Lee, Jongwan McDonald, Marissa Mhlanga, Nikiwe Kang, Jeon Woong Karnik, Rohit Tadesse, Loza F. More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets |
| title | More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets |
| title_full | More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets |
| title_fullStr | More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets |
| title_full_unstemmed | More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets |
| title_short | More than magnetic isolation: Dynabeads as strong Raman reporters toward simultaneous capture and identification of targets |
| title_sort | more than magnetic isolation dynabeads as strong raman reporters toward simultaneous capture and identification of targets |
| topic | Spectroscopy General Materials Science |
| url | https://hdl.handle.net/1721.1/153554 |
| work_keys_str_mv | AT leejongwan morethanmagneticisolationdynabeadsasstrongramanreporterstowardsimultaneouscaptureandidentificationoftargets AT mcdonaldmarissa morethanmagneticisolationdynabeadsasstrongramanreporterstowardsimultaneouscaptureandidentificationoftargets AT mhlanganikiwe morethanmagneticisolationdynabeadsasstrongramanreporterstowardsimultaneouscaptureandidentificationoftargets AT kangjeonwoong morethanmagneticisolationdynabeadsasstrongramanreporterstowardsimultaneouscaptureandidentificationoftargets AT karnikrohit morethanmagneticisolationdynabeadsasstrongramanreporterstowardsimultaneouscaptureandidentificationoftargets AT tadesselozaf morethanmagneticisolationdynabeadsasstrongramanreporterstowardsimultaneouscaptureandidentificationoftargets |