Two 'turn on' TCF-based fluorescence probes were developed for the detection of biological thiols (TCF-GSH and TCFCl-GSH). TCF-GSH was shown to have a high sensitivity towards glutathione (GSH) with ...a 0.28 μM limit of detection. Unfortunately, at higher GSH concentrations the fluorescence intensity of TCF-GSH decreased and toxicity was observed for TCF-GSH in live cells. However, TCFCl-GSH was shown to be able to detect GSH at biologically relevant concentrations with a 0.45 μM limit of detection. No toxicity was found for TCFCl-GSH and a clear 'turn on' with good photostability was observed for the exogenous addition of GSH, Cys and HCys. Furthermore, TCFCl-GSH was used to evaluate the effects of drug treatment on the levels of GSH in live cells.
An ESIPT-based 'AND' logic fluorescence probe (GSH-ABAH) was developed for the simultaneous detection of ONOO- and biological thiols. GSH-ABAH was shown to have good cell permeability and with the ...addition of just SIN-1 (ONOO- donor) or GSH, no fluorescence response was observed in live cells. However, in the presence of both analytes GSH-ABAH could be used to image exogenous ONOO- 'AND' GSH added to RAW264.7 cells.
We have developed a novel AND logic based fluorescence probe for the simultaneous detection of ONOO
and GSH (
). The
probe was synthesised over three steps starting from commercially available ...fluorescein. The probe was constructed by attaching the GSH reactive motif, 2,4-dinitrobenzenesulfonyl, to the previously reported boronate fluorescence based probe,
.
produced only a small fluorescence response towards the addition of GSH or ONOO
separately. However, when the probe was exposed to both analytes, there was a significant (40-fold) fluorescence enhancement.
demonstrated an excellent selectivity towards both GSH and ONOO
. In cellular imaging experiments the probe was shown to be cell permeable with no 'turn-on' response observed for the addition of either GSH or ONOO
separately. However, in the presence of both analytes, a clear fluorescence response was observed in live cells.
was further able to monitor the co-existence of metabolically produced ONOO
and GSH by exogenous stimulation.
A nitroreductase (NTR) responsive fluorescent probe with long wavelength fluorescence emission was used to determine the NTR activity of a selection of bacterial species under a range of different ...bacterial growth conditions ensuring applicability under multiple complex clinical environments, where sensitivity, reaction time, and the detection accuracy were suitable for planktonic cultures and biofilms.
A nitroreductase (NTR) responsive fluorescent probe with long wavelength fluorescence emission was used to determine the NTR activity of a selection of bacterial species under a range of different bacterial growth conditions.
Two boronate fluorescent probes have been developed for the detection of peroxynitrite (TCFB1 and TCFB2). TCFB1 was shown to have a low sensitvity towards peroxynitrite and have a poor solubility in ...aqueous solution whereas TCFB2 demonstrated high sensitivity towards peroxynitrite and mitochondria localisation with the ability to detect exogenous and endogenous peroxynitrite in live cells (Hep-G2, RAW 264.7, HeLa and A459).
Protein phosphorylation is a ubiquitous post-translational modification, which often acts as a switch to proteins’ activation and is frequently perturbed in diseases. Although many general ...phospho-protein detection tools are available, none of them offers information about the relative spatial arrangement of phosphorylated residues. Specifically, proximally phosphorylated residues are hallmarks of certain activated disease-relevant proteins. We herein report the first turn-on fluorescent sensor for the selective detection of proximally phosphorylated protein sites, suitable for application in both aqueous solutions and polyacrylamide gels.
We report on a superoxide anion (O
2
&z.rad;
−
) responsive fluorescent probe called
TCF-OTf
.
TCF-OTf
is able to monitor O
2
&z.rad;
−
production when the bacterial species
Pseudomonas aeruginosa
,
...Staphylococcus aureus
,
Escherichia coli
, and
Enterococcus faecalis
are exposed to chloramphenicol and heat shock at 50 and 58 °C.
We report on a superoxide anion (O
2
&z.rad;
−
) responsive fluorescent probe called
TCF-OTf
.
Traditionally, fluorescence probes have focused on the detection of a single biomarker for a specific process. In this work, we set out to develop a number of fluorescence probes that enable the ...detection of a chosen analyte in the presence of reactive oxygen/nitrogen species (ROS/RNS). These fluorescence probes when activated result in the formation of the highly fluorescent pink dye, resorufin. Therefore, we have labelled these fluorescent probes as 'Pinkments'. Our first 'Pinkment' was shown to detect biologically relevant concentrations of ONOO- and have an excellent selectivity against other ROS/RNS. Pinkment-OH was developed to provide a core unit which could be easily functionalised to produce a range of 'AND' based fluorescence probes for the detection of ROS/RNS and a second analyte. For proof of concept, we synthesised Pinkment-OTBS and Pinkment-OAc. These 'AND'-based probes were successfully shown to detect ROS/RNS and F- or esterase, respectively.
In this work, we have developed an ESIPT-based benzimidazole platform ( MO-E1 and MO-E2 ) for the two-photon cell imaging of ONOO − and a potential ONOO − -activated theranostic scaffold ( MO-E3 ). ...Each benzimidazole platform, MO-E1–3 , were shown to rapidly detect ONOO − at micromolar concentrations (LoD = 0.28 μM, 6.53 μM and 0.81 μM respectively). The potential theranostic MO-E3 was shown to release the parent fluorophore and drug indomethacin in the presence of ONOO − but unfortunately did not perform well in vitro due to low solubility. Despite this, the parent scaffold MO-E2 demonstrated its effectiveness as a two-photon imaging tool for the ratiometric detection of endogenous ONOO − in RAW264.7 macrophages and rat hippocampus tissue. These results demonstrate the utility of this ESIPT benzimidazole-based platform for theranostic development and bioimaging applications.
We present the concept of a versatile drug-loaded composite hydrogel that can be activated using an argon-based cold atmospheric plasma (CAP) jet to deliver both a drug and CAP-generated molecules, ...concomitantly, in a tissue target. To demonstrate this concept, we utilized the antibiotic gentamicin that is encapsulated in sodium polyacrylate (PAA) particles, which are dispersed within a poly(vinyl alcohol) (PVA) hydrogel matrix. The final product is a gentamicin-PAA-PVA composite hydrogel suitable for an on-demand triggered release using CAP. We show that by activating using CAP, we can effectively release gentamicin from the hydrogel and also eradicate the bacteria effectively, both in the planktonic state and within a biofilm. Besides gentamicin, we also successfully demonstrate the applicability of the CAP-activated composite hydrogel loaded with other antimicrobial agents such as cetrimide and silver. This concept of a composite hydrogel is potentially adaptable to a range of therapeutics (such as antimicrobials, anticancer agents, and nanoparticles) and activatable using any dielectric barrier discharge CAP device.
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