Antibody-Conjugated Polymersomes with Encapsulated Indocyanine Green J-Aggregates and High Near-Infrared Absorption for Molecular Photoacoustic Cancer Imaging

Design and Applications of Polymersomes for Oral Drug Administration

Polymersomes are nanostructures consisting of a hollow aqueous compartment enclosed by a coating of amphiphilic block copolymers. Owing to the entangled nature of their membrane, polymersomes exhibit higher mechanical stability than some other extensively studied nanostructures such as liposomes. This also enables the properties of the polymersome membrane to be more easily tuned to meet practical needs, making polymersomes promising carriers for drug delivery. Since the turn of the last century, the use of polymersomes has been exploited in diverse areas, ranging from protein therapy to medical imaging. Yet, discussions exploring the opportunities and challenges of the development of polymersomes for oral drug administration have been scant. This review addresses this gap by offering a snapshot of the current advances in the design, fabrication, and use of polymersomes as oral drug carriers. It is hoped that this review will not only highlight the practical potential of polymersomes for oral drug administration but will also shed light on the challenges determining the wider clinical potential of polymersomes in the forthcoming decades.

Targeted Delivery of Chlorin-e6-Loaded Carbon Nanotube-Based Nanobiocomposite to Cancer Stem Cells for Enhanced Photodynamic Therapy

Background: Globally, colorectal cancer (CRC) is the third-most diagnosed cancer among males and the second-most diagnosed cancer among females. In cancer, stem cells are a subset of neoplastic cells capable of tumorigenesis and exhibit properties like normal stem cells. Moreover, they are resistant to conventional cancer treatments and can repopulate the tumor following treatment. Cancer cells are stimulated to undergo apoptosis by photodynamic therapy (PDT), which involves a light source, a photosensitizer, and reactive oxygen species. Methods: In this study, colon cancer stem cells were isolated from colon cancer cells and characterized using flow cytometry and immunofluorescence techniques. To treat colon cancer stem cells (CCSCs), single-walled carbon nanotubes (SWCNTs) were coupled with hyaluronic acid (HA) and loaded with chlorin-e6 (Ce6). Nanobiocomposite toxicity was assessed using CCSCs with two fluences of 5 J/cm2 and 10 J/cm2. The cellular changes were observed at 24 and 48 h using microscopy, Results: LDH cytotoxicity assay, and cell death induction by annexin propidium iodide assay. An intracellular analysis of reactive oxygen species (ROS) detected oxidative stress within CCSCs. Conclusions: Overall, the results showed that the newly synthesized nanobiocomposite enhanced the ability of PDT to act as a photosensitizer carrier and induced cell death in CCSCs.

Surface Functionalization of Nanocarriers with Anti-EGFR Ligands for Cancer Active Targeting

Active cancer targeting consists of the selective recognition of overexpressed biomarkers on cancer cell surfaces or within the tumor microenvironment, enabled by ligands conjugated to drug carriers. Nanoparticle (NP)-based systems are highly relevant for such an approach due to their large surface area which is amenable to a variety of chemical modifications. Over the past decades, several studies have debated the efficiency of passive targeting, highlighting active targeting as a more specific and selective approach. The choice of conjugation chemistry for attaching ligands to nanocarriers is critical to ensure a stable and robust system. Among the panel of cancer biomarkers, the epidermal growth factor receptor (EGFR) stands as one of the most frequently overexpressed receptors in different cancer types. The design and development of nanocarriers with surface-bound anti-EGFR ligands are vital for targeted therapy, relying on their facilitated capture by EGFR-overexpressing tumor cells and enabling receptor-mediated endocytosis to improve drug accumulation within the tumor microenvironment. In this review, we examine several examples of the most recent and significant anti-EGFR nanocarriers and explore the various conjugation strategies for NP functionalization with anti-EGFR biomolecules and small molecular ligands. In addition, we also describe some of the most common characterization techniques to confirm and analyze the conjugation patterns.

Quantitative photoacoustic spectral transformations in theranostic solid lipid nanoparticles labelled with increasing concentrations of a photoacoustic NIR BODIPY

Solid lipid nanoparticles (SLNs) have shown great capabilities for drug delivery and are therefore attractive theranostic candidates when labelled with an imaging contrast agent. This work aims to create the first SLNs labelled for photoacoustic (PA) imaging by encapsulating a specially designed and near-infrared absorbing BODIPY dye (BY-aniline-Palm) into SLNs of dexamethasone palmitate. A one-pot formulation protocol enabled us to replace the prodrug with the BY-aniline-Palm label in various proportions up to 100%. Increasing the dye content resulted in complex but gradual transformations of the SLNs in terms of optical absorption and PA spectra, and the formation of aggregates at high concentration. A comprehensive and quantitative PA spectrometric study revealed a photoacoustic generation efficiency (PGE) that was spectrally varying and notably greater than 1. A joint spectral decomposition of the absorption and PA spectra into the sum of three Gaussian functions displayed a per-band evolution of the PGE when the concentration of BY-aniline-Palm varied and showed an interplay between the bands with a constant spectrum area. Finally, a novel quantitative PA spectroscopic approach, involving measurements at three different ambient temperatures, demonstrated that the remarkable PGE values arose from a significant thermo-elastic expansion of the SLNs during PA signal generation independently of the absorption band. This study highlights that labeled SLNs are promising agents for PA imaging and also unveils complex transformations that can occur in such nanosystems with a dye prone to aggregation.

Diagnosis and treatment status of inoperable locally advanced breast cancer and the application value of inorganic nanomaterials

Locally advanced breast cancer (LABC) is a heterogeneous group of breast cancer that accounts for 10-30% of breast cancer cases. Despite the ongoing development of current treatment methods, LABC remains a severe and complex public health concern around the world, thus prompting the urgent requirement for innovative diagnosis and treatment strategies. The primary treatment challenges are inoperable clinical status and ineffective local control methods. With the rapid advancement of nanotechnology, inorganic nanoparticles (INPs) exhibit a potential application prospect in diagnosing and treating breast cancer. Due to the unique inherent characteristics of INPs, different functions can be performed via appropriate modifications and constructions, thus making them suitable for different imaging technology strategies and treatment schemes. INPs can improve the efficacy of conventional local radiotherapy treatment. In the face of inoperable LABC, INPs have proposed new local therapeutic methods and fostered the evolution of novel strategies such as photothermal and photodynamic therapy, magnetothermal therapy, sonodynamic therapy, and multifunctional inorganic nanoplatform. This article reviews the advances of INPs in local accurate imaging and breast cancer treatment and offers insights to overcome the existing clinical difficulties in LABC management.

In vivo quantitative characterization of nano adjuvant transport in the tracheal layer by photoacoustic imaging

Adjuvants are indispensable ingredients in vaccine formulations. Evaluating the in vivo transport processes of adjuvants, particularly for inhalation formulations, presents substantial challenges. In this study, a nanosized adjuvant aluminum hydroxide (AlOOH) was synthesized and labeled with indocyanine green (ICG) and bovine serum albumin (BSA) to achieve strong optical absorption ability and high biocompatibility. The adjuvant nanomaterials (BSA@ICG@AlOOH, BIA) were delivered as an aerosol into the airways of mice, its distribution was monitored using photoacoustic imaging (PAI) in vivo. PAI results illustrated the gradual cross-layer transmission process of BIA in the tracheal layer, traversing approximately 250 µm from the inner layer of the trachea to the outer layer. The results were consistent with pathology. While the intensity of the BIA reduced by approximately 46.8% throughout the transport process. The ability of PAI for quantitatively characterized the dynamic transport process of adjuvant within the tracheal layer may be widely used in new vaccine development.