Indocyanine Green Nanoparticles: Are They Compelling for Cancer Treatment?

Abstract

Indocyanine green (ICG) is a Food and Drug Administration-approved near-infrared fluorescent dye, employed as an imaging agent for different clinical applications due to its attractive physicochemical properties, high sensitivity, and safety. However, free ICG suffers from some drawbacks, such as relatively short circulation half-life, concentration-dependent aggregation, and rapid clearance from the body, which would confine its feasible application in oncology. Here, we aim to discuss encapsulation of ICG within a nanoparticle formulation as a strategy to overcome some of its current limitations and to enlarge its possible applications in cancer diagnosis and treatment. Our purpose is to provide a short but exhaustive overview of clinical outcomes that these nanocomposites would provide, discussing opportunities, limitations, and possible impacts with regard to the main clinical needs in oncology.

Deuterated Indocyanine Green (ICG) with Extended Aqueous Storage Shelf‐Life: Chemical and Clinical Implications

“…From a broader biomedical perspective, the results of this study suggest additional future research directions for pursuit. For example, the idea that self‐aggregation of amphiphilic cyanine dyes, like ICG , can promote photoinduced electron transfer chemistry has been recognized by dye chemists for some time, [63] but has not yet been fully exploited as a rational design paradigm for next‐generation photodynamic therapy [53,64] . Likewise, deuterated polymethine cyanine dyes with a low propensity for photooxidative dimerization are promising future candidates for optimized super‐resolution microscopy [65]…”

Tumor Accumulation and Off-Target Biodistribution of an Indocyanine-Green Fluorescent Nanotracer: An Ex Vivo Study on an Orthotopic Murine Model of Breast Cancer

“…ICG is a passive tumor-targeted probe and its performance in ensuring the unambiguous identification of cancer tissue is still modest and insufficient in providing a trustworthy exploitation of this technique [ 1 ]. Therefore, most research focuses on designing nanocarriers as delivery systems for ICG with the aim of tackling some of its current issues and to expand its possible applications in cancer diagnosis and treatment [ 22 , 23 ]. Hence, the overall goal would be to develop systems with high specificity for tumors able to provide enhanced contrast between cancer tissues or affected lymph nodes and healthy tissue, in order to tailor specific surgeries [ 22 , 24 , 25 ].…”

Exploiting cyanine dye J-aggregates/monomer equilibrium in hydrophobic protein pockets for efficient multi-step phototherapy: an innovative concept for smart nanotheranostics

“…20 These strategies have proven to be effective for addressing the dye pharmacokinetics, but the photothermal degradation of ICG still remains the main challenge that has hampered its widespread use in clinical applications. 21,22 In 1936, E. Jelley discovered the molecular aggregation phenomenon of pseudo-isocyanine chloride (PIC), 23 introducing the concept of J-aggregates which have a bathochromic shift as a hallmark. Since then, plenty of work has been done concerning the light absorption properties of cyanine dyes.…”