کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2602981 1133803 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Intracellular oxidative stress and cadmium ions release induce cytotoxicity of unmodified cadmium sulfide quantum dots
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم محیط زیست بهداشت، سم شناسی و جهش زایی
پیش نمایش صفحه اول مقاله
Intracellular oxidative stress and cadmium ions release induce cytotoxicity of unmodified cadmium sulfide quantum dots
چکیده انگلیسی

ObjectiveTo fully understand the cytotoxicity of after-degradation QDs, we synthesized CdS QDs and investigated its toxicity mechanism.MethodsBiomimetic method was proposed to synthesize cadmium sulfide (CdS) QDs. Thereafter MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was conducted to evaluate their cytotoxicity. To investigate the toxicity mechanism, we subsequently conducted intracellular reactive oxygen species (ROS) measurement with DCFH-DA, glutathione (GSH) measurement with DTNB, and cellular cadmium assay using atomic absorption spectrometer. Microsized CdS were simultaneously tested as a comparison.ResultsMTT assay results indicated that CdS QDs are more toxic than microsized CdS especially at concentrations below 40 μg/ml. While microsized CdS did not trigger ROS elevation, CdS QDs increase ROS by 20–30% over control levels. However, they both deplete cellular GSH significantly at the medium concentration of 20 μg/ml. In the presence of NAC, cells are partially protected from CdS QDs, but not from microsized particles. Additionally, nearly 20% of cadmium was released from CdS nanoparticles within 24 h, which also accounts for QDs’ toxicity.ConclusionIntracellular ROS production, GSH depletion, and cadmium ions (Cd2+) release are possible mechanisms for CdS QDs’ cytotoxicity. We also suggested that with QD concentration increasing, the principal toxicity mechanism changes from intracellular oxidative stress to Cd2+ release.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Toxicology in Vitro - Volume 23, Issue 6, September 2009, Pages 1007–1013
نویسندگان
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