Indocyanine green: Intracellular uptake and phototherapeutic effects in vitro

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Abstract

Indocyanine green (JCG; absorption peak in human plasma 805 nm) was investigated for ICG-mediated phototherapy in vitro. The cellular uptake of ICG (1 μM-50 μM) into HaCaT keratinocytes after an incubation period of 24 h increased up to an intracellular ICG concentration of 12.1 ± 1.3 nmol per 106 cells. To examine dose dependent phototoxic effects in vitro, keratinocytes were incubated with 0 μM-50 μ M ICG for 24 h and irradiated by a diode laser (805 nm) with different energy densities (0, 12, 24, 48 J cm−2). All applied ICG concentrations except for 5 μM yielded a cell killing effect in combination with irradiation depending significantly on ICG concentration and light dose. Cell viability for dark control and cells incubated with 50 μM ICG and irradiated with 48 J cm−2 was 0.82 ± 0.15 and 0.07 ± 0.02, respectively. Sodium azide (100 mM), a quencher of reactive oxygen species, inhibited significantly the cell killing using 50 μM ICG and 24 J cm−2. Taken together, photoactivation of ICG by irradiation with a diode laser was shown to induced effectively cell killing of HaCaT keratinocytes. Moreover, this effect was inhibited by sodium azide, thus irradiation of ICG might induce a photodynamic reaction.

References (27)

  • M.R. Tripp et al.

    Effect of protein and electrolyte on the spectral stabilization of concentrated solutions of indocyanine green

  • M.L.J. Landsman et al.

    Light-absorbing properties, stability, and spectral stabilization of indocyanine green

    J. Appl. Physiol.

    (1976)
  • G. Paumgartner et al.

    Kinetics of indocyanine green removal from the blood

    NY Acad. Sci.

    (1970)
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