Challenges in the development of nanoparticle‐based imaging agents: Characterization and biology

Abstract

Despite imaging agents being some of the earliest nanomedicines in clinical use, the vast majority of current research and translational activities in the nanomedicine field involves therapeutics, while imaging agents are severely underrepresented. The reasons for this lack of representation are several fold, including difficulties in synthesis and scale‐up, biocompatibility issues, lack of suitable tissue/disease selective targeting ligands and receptors, and a high bar for regulatory approval. The recent focus on immunotherapies and personalized medicine, and development of nanoparticle constructs with better tissue distribution and selectivity, provide new opportunities for nanomedicine imaging agent development. This manuscript will provide an overview of trends in imaging nanomedicine characterization and biocompatibility, and new horizons for future development. This article is categorized under: Diagnostic Tools > in vivo Nanodiagnostics and Imaging Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine

Nanomaterials responding to microwaves: an emerging field for imaging and therapy

“…In the event that these modalities adopt companion nanomaterials for contrast enhancement, it is imperative to also consider the material chemical composition, projected human dose, interactions with biological tissue, clearance and most importantly the safety of these agents. 107 These factors must also be aligned carefully with the imaging system, to fully appreciate detection limits. 108 Lessons from the development of magnetic resonance imaging strongly indicate that equipment should evolve simultaneously with the chemical and biological development of the nanomaterial.…”

Nanomaterials for the Diagnosis and Treatment of Inflammatory Arthritis

“…Nanomaterial drug delivery is advantageous compared with conventional therapy because of its enhanced targeting specificity via controlled drug release, its increased ability to solubilize hydrophobic drugs, its synergistic combinatorial chemistry, and superior ability for drug delivery [39,40]. Advanced in vivo molecular imaging approaches like magnetic resonance imaging (MRI) can take images of the internal joint and cartilage [41,42]. Contrast agents used in MRI help in the differentiation between normal as well as abnormal tissues via magnetic signals [42].…”

Nanotechnology for Cancer Imaging: Advances, Challenges, and Clinical Opportunities

“…Iron oxide NPs were developed to image asialoglycoprotein receptors for detecting liver cancer by using MRI and were tested in a rat model (16,17). The first clinical trial on iron oxide NPs was for oral administration of this imaging agent for abdominal imaging in 1991 (18), which led to the first FDA approval of iron oxide NP application in 1993. Several forms of iron oxide NPs approved by the FDA or in Europe between 1993 and 2001 were later withdrawn because of toxicity issues (18).…”

“…The first clinical trial on iron oxide NPs was for oral administration of this imaging agent for abdominal imaging in 1991 (18), which led to the first FDA approval of iron oxide NP application in 1993. Several forms of iron oxide NPs approved by the FDA or in Europe between 1993 and 2001 were later withdrawn because of toxicity issues (18). Currently, the only FDA-approved iron oxide NP is ferumoxytol for treating iron deficiency anemia.…”

“…Currently, the only FDA-approved iron oxide NP is ferumoxytol for treating iron deficiency anemia. Ferumoxytol is frequently used as an off-label MRI contrast agent in various clinical trial stages (see table 2 of Crist et al [18] for additional information).…”