1887

Abstract

Summary: A trivalent lanthanide ion, erbium (Er), has been used in combination with a magnetic separation technique to isolate seven bacterial species from suspensions in 0·9% saline. Erbium has an exceptionally high atomic magnetic moment of 9·3 Bohr magnetons, and following addition as ErCl (final concentration 5 mM) to bacterial suspensions, it imparts the magnetic moment to the bacterial cells by ionic binding to the cell surface. Strains of and were obtained from the Quality Control Depository of The Cleveland Clinic Foundation, Cleveland, Ohio, USA as suspensions in 0·9% NaCl, in concentrations ranging from 10 to 10 c.f.u. ml. Bacteria were separated from solution inside a capillary flow cell exposed to a highly non-homogeneous magnetic field (maximum field intensity was 0·4 T) and quantified by a light scattering method. The quantity of cellular deposition in the magnetic field was correlated with the initial concentration of cells in the suspension, expressed in c.f.u. ml, and sample volume (1·5 and 3·0 ml), sample pH (prior to ErCl addition), affinity to Gram stain (negative vs positive) and species. Magnetic deposition was observed for concentrations as low as 10 and 10 c.f.u. ml, and a significant correlation between average scattered light intensity and initial cell concentration (correlation coefficient ≥ 0·98) was established in the range 10 to 10 c.f.u. ml for all but one species (). Magnetic deposition increased with increasing pH from 7·0 to 10·0 which is consistent with the prevailing view on the mechanism of the lanthanide ion binding to bacterial cells (ionic, to the cell surface). No significant difference in magnetic deposition was observed between individual strains, or between Gram-positive and -negative bacteria. Magnetic isolation of cells may find application in rapid total cell count determination, such as rapid urine screening.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-138-1-63
1992-01-01
2021-05-12
Loading full text...

Full text loading...

/deliver/fulltext/micro/138/1/mic-138-1-63.html?itemId=/content/journal/micro/10.1099/00221287-138-1-63&mimeType=html&fmt=ahah

References

  1. AHLBERG D.H, WALLEY D. 1982; A new sample pretreatment for increasing the effectiveness of the Ferrograph in capturing elastomer wear debris. Basic Fluid Power Research Journal 16:245–250
    [Google Scholar]
  2. ANDERSON D.P. 1983; Developments in analytical ferrography. Wear 90:187–197
    [Google Scholar]
  3. BOZORTH R.M. 1968 Ferromagnetism Princeton, NJ: D. van Nostrand Co., Inc;
    [Google Scholar]
  4. EVAN C.H. 1983; Application of ferrography to the study of wear and arthritis in human joints. Wear 90:281–292
    [Google Scholar]
  5. EVANS C.H, TEW W.P. 1983; Isolation of biological materials by use of erbium(II1)-induced magnetic susceptibilities. Science 213:653–654
    [Google Scholar]
  6. EVANS C.H. 1990; Biochemistry of the Lanthanides. New York: Plenum Press;
    [Google Scholar]
  7. GRAHAM M.D, SELVIN P.R. 1982; Separation of lanthanide binding cells. Transactions of the Institute of Electrical and Electronic Engineers 18: Magnetics 1523–1525
    [Google Scholar]
  8. HOYLE B.D, BEVERID T.J. 1983; Binding of metallic ions to the outer membrane of Escherichia coli. Applied and Environmental Microbiolog 46:749–752
    [Google Scholar]
  9. KEMSHEAD J.T, ELSO G, PATEL K. 1990; Immunomagnetic manipulation of bone marrow and tumor cells: an update. Bone Marrow Purging and Processing In 90 pp 235–252 Edited by Gross S., Gee A.P, Worthington-White D.A. New York: Wiley-Liss;
    [Google Scholar]
  10. LANSMAN J.B. 1990; Blockade of current through single calcium channels by trivalent lanthanide cations. Journal of General Physiology 95:679–696
    [Google Scholar]
  11. MULLEN M.D, WOLF D.C, FERRIS F.G, BEVERIDGE T.J, FLEMMING C.A, BAILEY G.W. 1989; Bacterial sorption of heavy metals. Applied and Environmental Microbiology 55:3143–3149
    [Google Scholar]
  12. PEZZLO M. 1988; Detection of urinary tract infections by rapid methods. Clinical Microbiology Reviews 1:268–280
    [Google Scholar]
  13. RUSSELL A.P, WESTCOTT V.C, DEMARIA A, JOHNS M. 1983; The concentration and separation of bacteria and cells by ferrography. Wear 90:159–165
    [Google Scholar]
  14. RUSSELL A, EVANS C.H, WESTCOTT V.C. 1987; Measurement of the susceptibility of paramagnetically labelled cells with paramagnetic solutions. Analytical Biochemistry 164:181–189
    [Google Scholar]
  15. SHERBET G.V, LAKSHMI M.S. 1973; Characterization of Escherichia coli cell surface by isoelectric equilibrium focusing. Biochimica et Biophysica Acra 298:50–58
    [Google Scholar]
  16. ZBOROWSKI M, MALCHESKY P.S, SAVON S.R, GREEN R, HALL G.S, HALL G.S, NOSÉ Y. 1991; Modification of ferrography method for analysis of lymphocytes and bacteria. Wear 142:135–149
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-138-1-63
Loading
/content/journal/micro/10.1099/00221287-138-1-63
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error