Department of Chemistry, Rhodes University, Grahamstown, South Africa.
J Fluoresc. 2012 Mar;22(2):771-8. doi: 10.1007/s10895-011-1012-2. Epub 2011 Nov 5.
The interaction of 2,2-diphenyl-1-picrylhydrazyl (DPPH(·) free radical with thiol-capped CdTe quantum dots (QDs) has been studied by UV-vis spectroscopy, steady state and time resolved fluorescence measurements. Addition of DPPH(·) radical to CdTe QDs resulted in fluorescence quenching. The interaction occurs through static quenching as this was confirmed by fluorescence lifetime measurements. Time course absorption studies indicates that DPPH(·) may be reduced by interaction with QDs to the substituted hydrazine form (2,2-diphenyl-1-picrylhydrazine) DPPH-H. The mechanism of fluorescence quenching of CdTe QDs by DPPH(·) is proposed.
通过紫外可见光谱、稳态和时间分辨荧光测量研究了 2,2-二苯基-1-苦肼基自由基(DPPH(·)自由基)与巯基封端的CdTe 量子点(QDs)的相互作用。向 CdTe QDs 中加入 DPPH(·)自由基会导致荧光猝灭。这种相互作用是通过静态猝灭发生的,这可以通过荧光寿命测量来证实。时程吸收研究表明,DPPH(·)可能通过与 QDs 的相互作用被还原为取代肼形式(2,2-二苯基-1-苦肼)DPPH-H。提出了 DPPH(·)猝灭 CdTe QDs 荧光的机制。