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The interaction of cytochrome c (Cyt c) with cardiolipin (CL) is believed to play an important role in the initial events of apoptosis. Herein, we investigate the structural changes of CL‐bound Fe2+Cyt c and the correlation with Cyt c release through surface‐enhanced Raman spectroscopy (SERS) on nickel substrates. The SERS results together with molecular dynamics simulation reveal that Fe2+Cyt c undergoes autoxidation and a relatively larger conformational alteration after binding with CL, inducing higher peroxidase activity of Cyt c and higher permeability of the CL membrane compared with those induced by the Fe3+Cyt c. The proapoptotic activity and SERS effect of the Ni nanostructures allow the in situ study of the redox‐state‐dependent Cyt c release from isolated mitochondria, which reveals for the first time that the ferrous state of Cyt c most likely plays a more important role in triggering apoptosis. [ABSTRACT FROM AUTHOR]

The interaction of cytochrome c (Cyt c) with cardiolipin (CL) is believed to play an important role in the initial events of apoptosis. Herein, we investigate the structural changes of CL‐bound Fe2+Cyt c and the correlation with Cyt c release through surface‐enhanced Raman spectroscopy (SERS) on nickel substrates. The SERS results together with molecular dynamics simulation reveal that Fe2+Cyt c undergoes autoxidation and a relatively larger conformational alteration after binding with CL, inducing higher peroxidase activity of Cyt c and higher permeability of the CL membrane compared with those induced by the Fe3+Cyt c. The proapoptotic activity and SERS effect of the Ni nanostructures allow the in situ study of the redox‐state‐dependent Cyt c release from isolated mitochondria, which reveals for the first time that the ferrous state of Cyt c most likely plays a more important role in triggering apoptosis. [ABSTRACT FROM AUTHOR]

Abstract: We report new developments on the chemical vapor deposition growth of 0.4nm single-walled carbon nanotubes (SWCNTs) inside the linear channels of the aluminophosphate zeolite, AlPO4-5 (AFI), single crystals (0.4nm-SWCNT@AFI). Ethylene (C2H4) and carbon monoxide (CO) were used as the feedstock. Polarized Raman spectroscopy was used to analyze the structure and quality of SWCNTs, both the radial breathing mode and G-band are much clearer and stronger than the samples grown by the old process which used template tripropylamine molecules for growing SWCNT@AFI. From the Raman spectra, it is clearly seen that the RBM is composed of two peaks at 535 and 551cm−1. By using the pseudopotential module in Material Studio to calculate the Raman lines, the 535cm−1 peak is attributed to the (5,0) SWCNTs and the 551cm−1 peak to the (3,3) SWCNTs. The abundance of (4,2) is relatively small. Thermal gravity analysis showed that while the samples grown by CO display less than 1wt% of carbon, for the samples heated in C2H4 atmosphere the weight percentage of SWCNTs is around 10%, which implies ∼30% of the AFI channels are occupied with SWCNTs, a significant increase compared with the previous samples. [Copyright &y& Elsevier]