TopBanner

Cart empty

User Account

 

Non-Conjugatable Phosphorescence (µS) Probes

We offer a patent protected unique range of organic Phosphorescence probes with microsecond (µS)  decay times (Lifetimes). We offer probes which are both highly water and sparingly water soluble for your every need: including Phosphorescence based imaging; O2 sensing; Protein tumbling and segmental motion observation; as a transduction element for collisional sensing (such as Halide Sensing) and as a sensitizer of Singlet Oxygen generation (1O2).

All our probes are sold prepacked and dry and are simply reconstituted by adding 50 µL of solvent.

Phos 1™

Phos 1™ is a water soluble zwitterionic probe, which can readily be excited at 300-400 nm, with λABS Max ≈ 325 nm. The phosphorescence is detectable in viscous solvents such as glycerol as illustrated in Figure 1.

figure 1

Figure 1. Excitation - Emission Maps (EEM) recorded for Phos 1™ dissolved at approximately the same concentrations in (A) MeOH and in (B) glycerol. Both data sets recorded at room temperature with solvents equilibrated against air. In methanol the phosphorescence is quenched, due to fast oxygen diffusion, and fluorescence therefore dominates. In glycerol, where oxygen diffuion is slow, the phosphorescence dominates and is centered around 550 nm following excitation at 320 nm. Note that the intensity is encoded in the color bar and scaled to 1 at the phosphorescence peak centered around 550 nm in glycerol. The fluorescence signal is thus ~10 times weaker in methanol.

 

The phosphorescence T1 emission is centered in the green ≈ 540 nm, Figure 1B and Figure 2 A, with a phosphorescence lifetime of 106 ± 1µS in glycerol, Figure 2B.

Phosphorescent probe Phos 1

Figure 2. (A) Phsophorescenec spectra recorded for Phos 1™ dissolved in glycerol. The exciation wavelength was 350 nm. (B) Phsophorescence decay recorded for Phos 1™ dissolved in air equilibrated glycerol at room temperature. The exciation wavelength was 350 nm and the emission collected at 530 nm. The blue line indicates a monoexponetial decay function with an emission lifetime of 106 ± 1 µs.

 

Phos 2™

Similar to Phos 1™, Phos 2™ can be excited 300-400 nm, with λABS Max ≈ 325 nm in Glycerol. Phos 2™ is less water soluble than Phos 1™ and is cationic, making ideal to bind to negatively charged surfaces such proteins or nanoparticles. Phos 2™ has a lifetime of 93 ± 0.4 µS in glycerol.

figure 2

Figure 3. (A) Absorption spectra recorded for Phos 2™ dissolved in glycerol. (B) Phsophorescenec spectra recorded for Phos 2™ dissolved in glycerol. The exciation wavelength was 350 nm. (C) Phsophorescence decay recorded for Phos 2™ dissolved in glycerol. The exciation wavelength was 350 nm. The blue line indicates a monoexponetial decay function with an emission lifetime of 93 ± 0.4 µs.

 

Phos Yellow™

Phos Yellow™ is a highly phosphorescent organic probe which can be excited from 300-380 nm. In air equilibrated glycerol, the fluorescence emission occurs at ≈400 nm and the phosphorescence is centered ≈ 540 nm, with a fwhm of ≈100 nm. The phosphorescence lifetime in air equilibrated glycerol at 22 C (em = 525 nm) is ≈ 120 µS. Phos Yellow™ is readily soluble in methanol, ethanol and acetone.

Spectra recorded for Phos Yellow.

Figure 4. (A) Absorption spectra recorded for Phos Yellow™ dissolved in ethanol and in glycerol. (B) Excitation-Emission Matrix (EEM) recorded in fluorescence mode for Phos Yellow™ dissolved in air equilibrated glycerol at room temperature. The fluorescence and phosphorescent regions are indicated by S1 and T1, respectively. (C) Phosphorescence spectra recorded for Phos Yellow™ dissolved in air equilibrated glycerol at room temperature. The excitation wavelength was 325 nm. (D) Phosphorescence decay recorded for Phos Yellow™ dissolved in glycerol. The excitation wavelength was 325 nm and the emission recorded at 525 nm. The blue line indicates a monoexponetial decay function corresponding to an emission lifetime of (120 ± 0.5) µs.

 

Phos Yellow 2™

Phos Yellow 2™ is slightly water soluble with better solubility in methanol than Phos Yellow™. Phos Yellow 2™ can readily be excited from 300-380 nm. Phos Yellow 2™ shows a much stronger phosphorescence at ≈ 540 nm than Phos Yellow™ in air equilibrated glycerol, and similar to Phos Yellow™ has a FWHM of ≈ 100 nm. The Phosphorescence tails into the yellow spectral region, which accounts for its unique yellow phosphorescence. The lifetime in air equilibrated glycerol is ≈ 113 µS (Ex 325 nm, Em 525 nm).

Spectra recorded for Phos Yellow2.

Figure 5. (A) Absorption spectra recorded for Phos Yellow2™ dissolved in ethanol and in glycerol. (B) Excitation-Emission Matrix (EEM) recorded in fluorescence mode for Phos Yellow2™ dissolved in air equilibrated glycerol at room temperature. The fluorescence and phosphorescent regions are indicated by S1 and T1, respectively. (C) Phosphorescence spectra recorded for Phos Yellow2™ dissolved in air equilibrated glycerol at room temperature. The excitation wavelength was 325 nm. (D) Phosphorescence decay recorded for Phos Yellow™ dissolved in glycerol. The excitation wavelength was 325 nm and the emission recorded at 525 nm. The blue line indicates a monoexponetial decay function corresponding to an emission lifetime of (113 ± 0.5) µs.

 
 

Methuselah Green 1™

Methuselah Green 1™ is a water soluble strongly phosphorescent probe which can be excited over a narrower absorption band than either Phos 1™ or Phos 2™, namely 300-350 nm, with λABS Max ≈ 320 nm in Glycerol, Figure 6A. Methuselah Green 1™ is zwitterionic with a very strong green phosphorescence (T1 emission), centered ≈ 525 nm, Figure 6B.

Phosphorescent probe Methuselah Green 1™

Figure 6. (A) Absorbance spectra recorded for Methuselah Green 1™ dissolved in methanol and in glycerol. (B) Excitatiation - Emission Map (EEM) recorded for Methuselah Green 1™ dissolved in glycerol. The phosphorescence region is centred around λem = 525 nm. All samples where in standard 1 cm quartz cuvettes.

 

Methuselah Green 1™ has a lifetime of 275 ± 1 µs in glycerol and is ideal for off-gated detection and imaging, Figure 7.

Phosphorescent probe  Methuselah Green 1

Figure 7. (A) Phsophorescenec spectra recorded for Methuselah Green 1™ dissolved in glycerol. The exciation wavelength was 350 nm. (B) Phsophorescence decay recorded for Methuselah Green 1™ dissolved in glycerol at 20 °C (68 °F) and placed in a standard 1 cm quartz cuvette equilibrated against air. The sample was excited at 350 nm and the emission recorded at 530 nm. The blue line indicates a monoexponetial decay function corresponding to an emission lifetime of 275 ± 1 µs.

 
 

Methuselah Green 2™

Methuselah Green 2™ is a strongly Phosphorescent probe, slightly less water soluble than Methuselah Green 1™. The Fluorescence band of Methuselah Green 2™ can be excited 300-380 nm, with the Phosphorescence, T1, band excited 290-350 nm, Figure 8A, in Glycerol. The absorption spectra is shown in Figure 8B and a typical phosphorescence emission centred at ~ 530 nm, with a FWHM of ~90 nm, Figure 8C. Methuselah Green 2™ is a cationic probe with a Phosphorescence lifetime of ~320 µS, Figure 8D.

MethuselahGreen2 w600

Figure 8. (A) Color map representation of the Methuselah Green 2™ emission. Fluorescence and phsophorescence regions are indicated. (B) Absorption spectra recorded for Methuselah Green 2™ dissolved in glycerol. (C) Phsophorescenec spectra recorded for Methuselah Green 2™ dissolved in glycerol. The exciation wavelength was 350 nm. (D) Phsophorescence decay recorded for Methuselah Green 2™ dissolved in glycerol. The exciation wavelength was 350 nm. The blue line indicates a monoexponetial decay function with an emission lifetime of 320 ± 1µs.

 
 

 

 w200

Methuselah Green 2™ is a strongly Phosphorescent probe. The Fluorescence band of Methuselah Green 2™ can be excited in the region 300-380 nm, with the Phosphorescence, T1, band excited 290-350 nm.

w456

Visual comparison of Phos 1 dissolved at the same concentration in methanol (left cuvette) and in glycerol (right cuvette). The cuvettes are placed on a UV light box and illuminated from below.

Cuvettes with the phosphorescent probe Phos Yellow dissolved in glycerol and in ethanol. The emission from the glycerol sample appears yellow when illuminated with UV light, from the ethanol sampe there is no visible emission.

Phos Yellow™ dissolved at the same concentrations (~5 µM) in air equilibrated glycerol (left cuvette) and in ethanol (right cuvette). The cuvettes are illuminated from below with UV light.