Cyanine based Nanoprobes for Cancer Theranostics

Abstract

Cyanine dyes are greatly accredited in the development of non‐invasive therapy that can “see” and “treat” tumor cells via imaging, photothermal and photodynamic treatment. However, these dyes suffer from poor pharmacokinetics inducing severe toxicity to normal cells, insufficient accumulation in tumor regions and rapid photobleaching when delivered in free forms. Nanoparticles engineered to encapsulate these compounds and delivering them into tumor regions have increased rapidly, however, so far, these nanoparticles (NPs) have not proved to be so effective to circumvent existing challenges. Newly designed multifunctional smart nanocarriers that can improve phototherapeutic properties of these dyes, co‐encapsulate multiple potent therapeutic compounds, and simultaneously overcome limitations related to tumor recurrence, metastases, limited intracellular uptake, and tumor hypoxia have potential to revolutionize modern paradigm of cancer therapy. Such cyanine based multifunctional nanocarriers integrating imaging and therapy in a single platform can effectively produce better clinical outcomes in cancer treatment. This review briefly summarizes recent advancements of cyanine nanoprobes that are currently used as imaging/phototherapeutic agents in unimodal/bimodal/trimodal cancer theranostics. Finally, we conclude this review by addressing challenges of pre‐existing therapeutic systems and designs adopted to overcome them with a brief insight assimilating future perspective of emerging cyanine‐based NPs in cancer theranostics.

Photothermal therapy and photoacoustic imaging via nanotheranostics in fighting cancer

“…Organic small molecule-based PTAs, such as cyanine dyes and porphyrin, have been frequently used in both imaging and therapy of cancer. 139,140 But they share the same disadvantages, including poor aqueous solubility, limited tumour accumulation, bioavailability, photobleaching, and low photothermal efficiency. Unlike delivery of small molecules in free forms, nanocarriers based delivery tools outperform therapeutic efficacy via improved solubilization and pharmacokinetics, enhanced tumour penetration and retention in vivo, resistance to photobleaching, and increasing the photothermal efficiency.…”

Tumor Theranostics of Transition Metal Ions Loaded Polyaminopyrrole Nanoparticles

“…Tumor theranostics is a vitally significant application for nano-medical science 1 - 7 . Plenty of nanoplatforms, constructing from noble metal nanoparticles (NPs) 8 - 11 , carbon-based materials 12 - 14 , organic compounds 15 , 16 , polymers 17 , 18 and some other inorganic NPs such as Fe 3 O 4 19 , 20 , SiO 2 21 - 24 , copper chalcogenides 25 - 27 , are tested as novel agents for tumor diagnosis and combination therapies. Apart from these existing building blocks, transitional metal ions also exhibit theranostic functions 28 - 31 .…”

Synthesis and Supramolecular Functional Assemblies of Ratiometric pH Probes

“…Additionally,c yanine dyes are biocompatible;s how low cytotoxicity in living cells;a nd have been widely appliedi nt he sensing of metal ions, pH, anions, reactive small molecules, biomacromolecules ande nvironment-related factorss uch as temperature, polarity and viscosity. [16][17][18] An umber of synthetic procedures towards the polymethine skeleton of cyanines have been described in the literature. [19] The general synthetic approachc onsists of the condensation of an indolinium with the corresponding unsaturated electrophiles ( Figure 3B).…”