Surface enhanced fluorescence (SEF) is observed with very high contrast (100–200) from single E. coli bacteria cells labeled with Carbon nanodots (CDs), on aluminum foil and aluminum film. Likely, it is the first application of organic CDs in SEF. SEF with 633 nm excitation delivered a much higher contrast than SEF with 532 nm excitation. Contrast is the ratio of the fluorescent intensities of labeled CDs to unlabeled (control) cells. High contrast with CDs is also observed on the gold film, silicon, and glass. Enhancement factor (EF) is the ratio of the signal on the metal substrate to the signal on the glass. Single E. coli cells, labeled with commercial graphene quantum dots (GCDs), demonstrated higher EFs (44 on gold, 35 on Al film), but at least one order of magnitude lower contrast (7–10 on aluminum and gold) than cells labeled with organic CDs. Therefore, organic CDs can be a good choice for cell imaging/labeling, capable of achieving a signal to noise (standard deviation of the control) as high as 700 on Al film. Overall, aluminum foil and film are highlighted as inexpensive but efficient substrates for Metal Enhanced Fluorescence, particularly MEF of bacterial cells stained with CDs.

从铝箔和铝膜上标记有碳纳米点（CD）的单个大肠杆菌细胞中观察到具有非常高的对比度（100–200）的表面增强荧光（SEF）。这很可能是有机CD在SEF中的首次应用。633 nm激发的SEF的对比度比532 nm激发的SEF高得多。对比是标记CD与未标记（对照）细胞的荧光强度之比。在金膜，硅和玻璃上也观察到与CD的高对比度。增强因子（EF）是金属基板上的信号与玻璃上的信号之比。单一大肠杆菌标有商业石墨烯量子点（GCD）的细胞显示出更高的EF（金44，铝膜35），但对比度比标有有机CD的细胞低至少一个数量级（铝和金7–10） 。因此，有机CD是细胞成像/标记的良好选择，能够在Al膜上实现高达700的信噪比（对照的标准偏差）。总体而言，铝箔和薄膜是金属增强荧光的廉价但有效的基材，特别是CD染色的细菌细胞的MEF。