The use of chloroaluminium phthalocyanine tetrasulfonate (AlPcTS) for time-delayed fluorescence imaging

Abstract

Phthalocyanine derivatives are currently under investigation for use in photodynamic therapy, which is a promising cancer treatment. These materials, which display preferential uptake in cancerous cells, also exhibit high fluorescence yields and can be used for tumour detection. Problems with steady-state fluorescence techniques such as excitation scatter and background autofluorescence can be eliminated by using time-resolved imaging techniques without the need for filters. A tissue phantom was assembled to test a constructed time-gated imaging system by drilling 36 wells of varying diameter and depth (10 mm to 1 mm) into a block of polymethyl methacrylate (PMMA). The system was used to record images of chloroaluminium phthalocyanine tetrasulfonate (AlPcTS) at differing concentrations in neat aqueous solvent and cell suspensions within the wells. A mixture of Intralipid (to mimic tissue scatter) and Evan's blue (to mimic tissue absorption) of depths ranging from 1 mm to 10 mm was placed on top of the PMMA block. The ensuing images were analysed using signal-to-noise ratios and contrast-detail curves. The results indicate that the time-gated imaging system can prevent background excitation scatter from distorting the fluorescence signal from a longer-lived photosensitizer without the need for filters.

Reaction of Perrhenate with Phthalocyanine Derivatives in the Presence of Reducing Agents and Rhenium Oxide Nanoparticles in Biomedical Applications

“…A similar peak (at 2255 cm À 1 ) was observed in the hydrolysis product of TAPc (Scheme S4). 1 H NMR and 13 C NMR spectroscopy were used to further confirm the structures of the phthalonitriles (Figure S6 and S7). The NMR spectra of both the nitro-and aminoÀ phthalonitriles are in agreement with known spectral data.…”

“…Different metals have been successfully incorporated into the phthalocyanine cavity yielding metallophthalocyanines (MPcs). Owing to their versatility and interesting material properties, metallophthalocyanines have made their way to the medical industry [1] . Conventionally, MPcs are extensively employed as photosensitizers, [2] in dye‐sensitized solar cells, [3] and as photocatalysts, [4] among a myriad of other applications [5] .…”

“…Owing to their versatility and interesting material properties, metallophthalocyanines have made their way to the medical industry. [1] Conventionally, MPcs are extensively employed as photosensitizers, [2] in dye-sensitized solar cells, [3] and as photocatalysts, [4] among a myriad of other applications. [5] Despite the wide study of MPcs, literature on rhenium phthalocyanines is scarce and limited to oxo, halogeno, and nitrido complexes.…”

Nonlinear Optical Response of Chloroaluminiumphthalocyanine Encapsulated by Silica Core−Shell Particles

“…Phthalocyanines (Pc) are known to possess interesting nonlinear optical properties and have been proposed as materials for optical limiting. –, – The photophysical properties of Pc can be altered significantly by incorporating different central metal ions into the macrocycle (MPc). These materials exhibit a variety of nonlinear optical mechanisms, depending on the pulse width and wavelength of excitation.…”

Determination of the modulation transfer function for a time-gated fluorescence imaging system

“…The calculated resolution in this study is in agreement with a previous investigation, which demonstrates the constructed imaging system's ability to resolve 10 Ϫ4 M AlPcTS fluorescence of 1 mm in diameter at depths ranging from 1 to 3 mm. 30 Figure 11 shows a line resolution test target placed on top of the 10 Ϫ4 M AlPcTS at a 6.0-ns delay as an additional way to estimate the MTF. It can be seen that at 1 lp/mm the lines of the test target can be made out, which is in agreement with the quantitative results of the MTFs.…”