Highly sensitive and ratiometric luminescence sensing of heparin through templated cyanostilbene assemblies

Abstract

The assembly of organic dyes on bio-molecular templates is an attractive strategy for the creation of bio-materials with intriguing optical properties. This principle is exploited here for the detection of...

Host‐Guest Assemblies of Cyanostilbenes and Cucurbit[8]uril: Luminescence Modulation, Photoreactivity Control and Energy Transfer Studies

“…Dynamic light scattering (DLS) measurements further corroborated the formation of aggregates for the derivatives with longer alkyl chains (N≥8) (Table S1 in Supporting Information) and they formed entangled nanofibers as seen from field emission scanning electron microscopic (FESEM) images (Figure S1 in Supporting Information) [31a] . The shorter chain derivatives displayed weak cyan emission (λ em =450 nm) in all these media (Figure 1b, 1d, and 1 f) which was attributed to their monomeric forms [30,31b] . On the other hand, for the longer chain derivatives (specifically for N=10 and 12), broad and highly red shifted (∼ 180 nm Stokes shift) excimeric emissions (λ em =540 nm) [30,31] were observed (Figure 1b, 1d, and 1 f) in all the three media.…”

Multicolor-Luminescence Including White Light by Photomodulation of Supramolecular Assemblies in Aqueous Media

“…The preparation of Z- CSN derivatives is described in our previous reports. ,, Characterization data of the derivatives and their photoproducts are described in the Supporting Information.…”

“…29 At water fractions of 90% or above, a new broad and red-shifted greenish-yellow emission band (λ em = 536 nm) was observed for Z-CS10 (40 μM) (Figure S2c), which characterized the excimeric emission of the CS chromophores as observed previously by us. 29,30,47 The average fluorescence lifetime (τ avg ) for Z-CS10 (40 μM) at the 536 nm band was 4.69 ns (Figure 1c and Table 1), whereas the monomeric Z-CS2 exhibited a much shorter lifetime of 0.36 ns at its emission maxima at 450 nm. Its aggregated aqueous solution was stable for at least 2 days under dark conditions suggesting reasonable stability (Figure S2d).…”

“…CS chromophores in their self-assembled state in aqueous media , and also a modulation of their luminescence either by employing macrocyclic hosts or through electrostatic binding with a biopolyanion. ,, We envisaged that light-induced transformation of the anisotropic nanofibers of the supramolecular assemblies of Z- CS10 and Z- CS12 would lead to a modulation of their emission properties in a spatio-temporal manner. Indeed, when the supramolecular assemblies of Z- CS10 and Z- CS12 in aqueous media were subjected to UV irradiation or sunlight, they underwent photoisomerization as well as photoelectrocyclization.…”

Luminescence Sensing of Biomacromolecules Heparin and Protamine in 100% Human Serum and Plasma by Supramolecular Polymeric Assemblies

“…This significantly compromises the electrostatic binding and makes it extremely difficult to achieve the level of binding affinity that would allow the detection of heparin in a clinically relevant concentration range . Therefore, in most of the cases, the detection of heparin has been achieved in only diluted (5–10%) serum or plasma media, − whereas only a few examples have documented heparin detection in 50% or higher contents of serum and plasma. − Protamine sulfate (PS), an arginine-rich protein, is a known antidote to heparin and is administered in the treatment of heparin overdosage . PS utilizes its multiple positive charges to bind to heparin and subsequently neutralize its effect, although differentiation between biologically active and inactive heparin is not possible due to nonspecific electrostatic interactions.…”