Bulk glass fluorescence measurements with 532 nm excitation.Of selleckchem Cisplatin greatest interest to this work is the glass fluorescence background in the region of the Qdot 800 emission (as described below), which is between 700 and 900 nm, with a peak at 780 nm. These results suggest that the best two glasses are both commercial lead-silicate glasses from Schott; the F2 glass used in earlier Inhibitors,Modulators,Libraries  work, and the F2HT glass proposed for use here. A third candidate in Inhibitors,Modulators,Libraries LLF1, another Schott lead silicate which has also found extensive use in fabricating soft glass fibers and is considered in the modeling results shown in Section 7.The bulk measurements suggest that since all other relevant material parameters are virtually identical between the two different glasses, changing glass from F2 to F2HT should result in almost a 50% reduction in the observed glass fluorescence.
3.?Experimental DesignA commercially available CdSe quantum dot Qdot? 800 ITKTM from Invitrogen was selected for use in this research. Unlike conventional organic fluorophores, quantum dots are virtually Inhibitors,Modulators,Libraries immune to the effects of photobleaching, meaning that direct comparisons between samples can be readily made as the fluorescence signal does not decrease over time. Additionally, due to the optical characteristics of Qdots, it is possible to excite the molecules at a wavelength that is Inhibitors,Modulators,Libraries significantly shorter than their fluorescence emission wavelength (��~250 nm separation in this case: excitation at 532 nm, emission peak at 780 nm), which reduces the need to spectrally filter out residual pump light.
Finally, they have a relatively high absorption coefficient (~4 �� 106 M?1 cm?1 Drug_discovery at 532 nm) compared to other organic flurophores such as Rhodamine B which has an absorption coefficient of 8.2 �� 104 at 532 nm. The Qdots in this case were unconjugated, and suspended in decane (CH3-(CH2)8-CH3). Note that conjugated Qdots could readily be used, and indeed protein detection down to 1 nM has previously been demonstrated in fiber using a similar system to that described here .The fiber used for these experiments was an in-house fabricated suspended core MOF as shown in Figure 2, referred to hereafter as a wagon-wheel (WW) fiber. The fiber was fabricated via preform extrusion and subsequent fiber drawing performed using a cane-in-tube technique  to allow the production of a relatively small core within a robust fiber geometry (core diameter ~1.
7 ��m, outer diameter 130 ��m). To the best of our knowledge this is the first MOF reported to have been fabricated from Schott F2HT glass , with the primary difference between this glass and the more commonly used F2 [14,19,20] being improved UV transmission  and a reduced intrinsic glass fluorescence, which was discussed in detail in Section 2. F2HT glass was used as not the material for the central cane, with the outer tube being fabricated from standard F2 glass.