Theranostic Applications of Nanomaterials in Cancer: Drug Delivery, Image-Guided Therapy, and Multifunctional Platforms.

Successful cancer management depends on accurate diagnostics along with specific treatment protocols. Current diagnostic techniques need to be improved to provide earlier detection capabilities, and traditional chemotherapy approaches to cancer treatment are limited by lack of specificity and systemic toxicity. This review highlights advances in nanotechnology that have allowed the development of multifunctional platforms for cancer detection, therapy, and monitoring. Nanomaterials can be used as MRI, optical imaging, and photoacoustic imaging contrast agents. When used as drug carriers, nanoformulations can increase tumor exposure to therapeutic agents and result in improved treatment effects by prolonging circulation times, protecting entrapped drugs from degradation, and enhancing tumor uptake through the enhanced permeability and retention effect as well as receptor-mediated endocytosis. Multiple therapeutic agents such as chemotherapy, antiangiogenic, or gene therapy agents can be simultaneously delivered by nanocarriers to tumor sites to enhance the effectiveness of therapy. Additionally, imaging and therapy agents can be co-delivered to provide seamless integration of diagnostics, therapy, and follow-up, and different therapeutic modalities such as chemotherapy and hyperthermia can be co-administered to take advantage of synergistic effects. Liposomes, metallic nanoparticles, polymeric nanoparticles, dendrimers, carbon nanotubes, and quantum dots are examples of nanoformulations that can be used as multifunctional platforms for cancer theranostics. Nanomedicine approaches in cancer have great potential for clinically translatable advances that can positively impact the overall diagnostic and therapeutic process and result in enhanced quality of life for cancer patients. However, a concerted scientific effort is still necessary to fully explore long-term risks, effects, and precautions for safe human use

Development of a PLGA Nanoparticle Drug Delivery System Containing Imaging/Hyperthermia and Chemotherapy Agents

Nanoparticulate drug delivery systems have the potential to allow delivery of diagnostic and therapeutic agents to tumor sites in a targeted manner. The objective of this study was to develop biodegradable poly (DL-lactide-co-glycolic acid) (PLGA) nanoparticles loaded with an imaging/hyperthermia agent and a chemotherapy agent to allow for simultaneous diagnostics and treatment. Indocyanine Green (ICG) was selected as the imaging/hyperthermia agent, and doxorubicin (DOX) as the chemotherapy agent. The modified oil in water emulsion solvent evaporation method was used for PLGA nanoparticle preparation. To achieve an optimal degree of incorporation and particle size, we systematically assessed four independent processing variables including amount of PLGA, initial ICG amount, initial DOX amount, and PVA concentration. For every combination, we measured the nanoparticle size and the percent entrapment of ICG and DOX into the PLGA nanoparticles. The nanoparticles produced by optimal formulation had sizes of 171± 2 nm, (n=3) with a low polydispersity index (0.040 ± 0.014, n=3). We determined the entrapment efficiency (by fluorescence measurements using DMSO burst release) as 44.4 ± 1.6 % for ICG and 74.3 ± 1.9 % for DOX. Drug loading was 0.015 ± 0.001 % w/w for ICG and 0.022 ± 0.001% w/w for DOX (n=3). The release pattern was biphasic

Preparation and Characterization of a Polymeric (PLGA) Nanoparticulate Drug Delivery System With Simultaneous Incorporation of Chemotherapeutic and Thermo-Optical Agents.

The objective of this study was to develop biodegradable poly (DL-lactide-co-glycolic acid) (PLGA) nanoparticles simultaneously loaded with indocyanine green (ICG) and doxorubicin (DOX). The modified oil in water single emulsion solvent evaporation method was used. To enhance the incorporation of both agents and control particle size, four independent processing parameters including amount of polymer, initial ICG content, initial DOX content, and concentration of poly-vinyl alcohol (PVA) were investigated. The ICG and DOX entrapment in nanoparticles as well as the nanoparticle size were determined. The nanoparticles produced by standardized formulation were in the range of 171+/-2 nm (n=3) with low polydispersity index (0.040+/-0.014, n=3). The entrapment efficiency was determined by spectrofluorometer measurements. The efficiency was 44.4+/-1.6% for ICG and 74.3+/-1.9% for DOX. Drug loading was 0.015+/-0.001%, w/w, for ICG and 0.022+/-0.001%, w/w, for DOX (n=3). The release pattern was biphasic. ICG and DOX loaded-nanoparticle preparation was standardized based on the following parameters: PLGA concentration, PVA concentration and initial drug content