Cytocompatibility of stabilized black phosphorus nanosheets tailored by directly conjugated polymeric micelles for human breast cancer therapy

An optical sensing platform for the detection of anti-cancer drugs and their cytotoxicity screening using a highly selective phosphorene-based composite

Monitoring therapeutic drugs and their elimination is crucial because they may cause severe side effects on the human body. Methotrexate (MTX) is a widely used anti-cancer drug, which is highly expensive, and the detection of unwanted overdoses of MTX using traditional procedures is time-consuming and involves complex instrumentation. In this work, we have developed a nanocomposite material using phosphorene, cystine, and gold (Ph-Cys-Au) that shows excellent optical properties. This nanocomposite can be used as an optical sensing platform for the detection of MTX in the range 0-260 μM. The synthesized sensing platform is very sensitive, selective, and cost-effective for the detection of MTX. Ph-Cys-Au can effectively detect MTX in aqueous media with a limit of detection (LOD) of about 0.0266 nM (for a linear range of 0-140 μM) and 0.0077 nM (for a linear range of 160-260 μM). The nanocomposite is equally selective for real samples, such as human blood serum (HBS) and artificial urine (AU) with a LOD of 0.0914 nM and 0.0734 nM, respectively. We have also determined the limit of quantification (LOQ); the LOQ values for the aqueous media were 0.0807 nM (for a linear range of 0-140 μM) and 0.0234 nM (for a linear range of 160-260 μM), whereas, the values for HBS and AU were around 0.2771 nM and 0.2226 nM, respectively. Moreover, the nanocomposite also provides a feasible platform for cytotoxicity screening in cancerous cells (Caco-2 cell lines) and non-cancerous cells (L-929 cell lines).

Modulating pro-adhesive nature of metallic surfaces through a polypeptide coupling via diazonium chemistry

The design of biomaterials able to facilitate cell adhesion is critical in the field of tissue engineering. Precise control of surface chemistry at the material/tissue interface plays a major role in enhancing the interactions between a biomaterial and living cells. Bio-integration is particularly important in case of various electrotherapies, since a close contact between tissue and electrode's surface facilitates treatment. A promising approach towards surface biofunctionalization involves the electrografting of diazonium salts followed by the modification of organic layer with pro-adhesive polypeptides. This study focuses on the modification of platinum electrodes with a 4-nitrobenzenediazonium layer, which is then converted to the aminobenzene moiety. The electrodes are further biofunctionalized with polypeptides (polylysine and polylysine/laminin) to enhance cell adhesion. This study also explores the differences between physical and chemical coupling of selected polypeptides to modulate pro-adhesive nature of Pt electrodes with respect to human neuroblastoma SH-SY5Y cells and U87 astrocytes. Our results demonstrate the significant enhancement in cell adhesion for biofunctionalized electrodes, with more amplified adhesion noted for covalently coupled polypeptides. The implications of this research are crucial for the development of more effective and functional biomaterials, particularly biomedical electrodes, which have the potential to advance the field of bioelectronics and improve patients' outcomes.

Disposable electrochemical platform based on solid-binding peptides and carbon nanomaterials: an alternative device for leishmaniasis detection

Neglected tropical diseases are those caused by infectious agents or parasites and are considered endemic in low-income populations. These diseases also have unacceptable indicators and low investment in research, drug production, and control. Tropical diseases such as leishmaniasis are some of the main causes of morbidity and mortality around the globe. Electrochemical immunosensors are promising tools for diagnostics against these diseases. One such benefit is the possibility of assisting diagnosis in isolated regions, where laboratory infrastructure is lacking. In this work, different peptides were investigated to detect antibodies against Leishmania in human and canine serum samples. The peptides evaluated (395-KKG and 395-G) have the same recognition site but differ on their solid-binding domains, which ensure affinity to spontaneously bind to either graphene oxide (GO) or graphene quantum dots (GQD). Cyclic voltammetry and differential pulse voltammetry were employed to investigate the electrochemical behavior of each assembly step and the role of each solid-binding domain coupled to its anchoring material. The graphene affinity peptide (395-G) showed better reproducibility and selectivity when coupled to GQD. Under the optimized set of experimental conditions, negative and positive human serum samples responses were distinguished based on a cut-off value of 82.5% at a 95% confidence level. The immunosensor showed selective behavior to antibodies against Mycobacterium leprae and Mycobacterium tuberculosis, which are similar antibodies and potentially sources of false positive tests. Therefore, the use of the graphene affinity peptide as a recognition site achieved outstanding performance for the detection of Leishmania antibodies.

Towards the Future of Polymeric Hybrids of Two-Dimensional Black Phosphorus or Phosphorene: From Energy to Biological Applications

With the advent of a new 2D nanomaterial, namely, black phosphorus (BP) or phosphorene, the scientific community is now dedicated to focusing on and exploring this 2D material offering elusive properties such as a higher carrier mobility, biocompatibility, thickness-dependent band gap, and optoelectronic characteristics that can be harnessed for multiple applications, e.g., nanofillers, energy storage devices, field effect transistors, in water disinfection, and in biomedical sciences. The hexagonal ring of phosphorus atoms in phosphorene is twisted slightly, unlike how it is in graphene. Its unique characteristics, such as a high carrier mobility, anisotropic nature, and biocompatibility, have attracted much attention and generated further scientific curiosity. However, despite these interesting features, the phosphorene or BP poses challenges and causes frustrations when it comes to its stability under ambient conditions and processability, and thus in order to overcome these hurdles, it must be conjugated or linked with the suitable and functional organic counter macromolecule in such a way that its properties are not compromised while providing a protection from air/water that can otherwise degrade it to oxides and acid. The resulting composites/hybrid system of phosphorene and a macromolecule, e.g., a polymer, can outperform and be exploited for the aforementioned applications. These assemblies of a polymer and phosphorene have the potential for shifting the paradigm from exhaustively used graphene to new commercialized products offering multiple applications.

Boron- and phosphorus-containing molecular/nano platforms: exploiting pathological redox imbalance to fight cancer

Cancer is currently the second leading cause of death globally. Despite multidisciplinary efforts, therapies to fight various types of cancer still remain inefficient. Reducing high recurrence rates and mortality is thus a major challenge to tackle. In this context, redox imbalance is an undervalued characteristic of cancer. However, it may be targeted by boron- and phosphorus-containing materials to selectively or systemically fight cancer. In particular, boron and phosphorus derivatives are attractive building blocks for rational drug discovery due to their unique and wide regioselective chemistry, high degree of tuneability and chemical stability. Thus, they can be meticulously employed to access tunable molecular platforms to selectively exploit the redox imbalance of cancer cells towards necrosis/apoptosis. This field of research holds a remarkable potential; nevertheless, it is still in its infancy. In this mini-review, we underline recent advances in the development of boron- or phosphorus-derivatives as molecular/nano platforms for rational anticancer drug design. Our goal is to provide comprehensive information on different methodologies that bear an outstanding potential to further develop this very promising field of research.

2D Hetero-Nanoconstructs of Black Phosphorus for Breast Cancer Theragnosis: Technological Advancements

As per global cancer statistics of 2020, female breast cancer is the most commonly diagnosed cancer and also the foremost cause of cancer death in women. Traditional treatments include a number of negative effects, making it necessary to investigate novel smart drug delivery methods and identify new therapeutic approaches. Efforts for developing novel strategies for breast cancer therapy are being devised worldwide by various research groups. Currently, two-dimensional black phosphorus nanosheets (BPNSs) have attracted considerable attention and are best suited for theranostic nanomedicine. Particularly, their characteristics, including drug loading efficacy, biocompatibility, optical, thermal, electrical, and phototherapeutic characteristics, support their growing demand as a potential substitute for graphene-based nanomaterials in biomedical applications. In this review, we have explained different platforms of BP nanomaterials for breast cancer management, their structures, functionalization approaches, and general methods of synthesis. Various characteristics of BP nanomaterials that make them suitable for cancer therapy and diagnosis, such as large surface area, nontoxicity, solubility, biodegradability, and excellent near-infrared (NIR) absorption capability, are discussed in the later sections. Next, we summarize targeting approaches using various strategies for effective therapy with BP nanoplatforms. Then, we describe applications of BP nanomaterials for breast cancer treatment, which include drug delivery, codelivery of drugs, photodynamic therapy, photothermal therapy, combined therapy, gene therapy, immunotherapy, and multidrug resistance reversal strategy. Finally, the present challenges and future aspects of BP nanomaterials are discussed.

Biodegradable freestanding rare-earth nanosheets promote multimodal imaging and delivers CRISPR-Cas9 plasmid against tumor

Designing nanomaterials for bio-imaging and drug delivery for advanced cancer therapy with biodegradability and biocompatibility is a promising but challenging frontier. Herein, we assembled biodegradable and biocompatible ultrathin rare-earth erbium/dysprosium nanosheets that improve contrast in multimodal bio-imaging settings (MRI and X-ray CT) and deliver CRISPR-Cas9 plasmid to treat tumors.

Black phosphorus conjugation of chemotherapeutic ginsenoside Rg3: enhancing targeted multimodal nanotheranostics against lung cancer metastasis

It is a significant challenge in lung cancer chemophotothermal (CPT) therapy to develop multifunctional theranostic nanoagent (MTN) for precise targeting and successful tumor treatments, especially for lung metastasis. To overcome this problem, we effectively design and construct multifunctional black phosphorus (BP) nanoagents, BPs/G-Rg3@PLGA. BPs quantum dots (BPsQDs) are co-loaded onto poly(lactic-co-glycolic acid) (PLGA) with subsequent conjugations of a cancer therapeutic compound, ginsenoside Rg3 (G-Rg3), in this composite nanoagent. The in vivo delivery findings suggest that BPs/G-Rg3@PLGA has an excellent affinity for primary tumors and metastatic lung tumors. Furthermore, when paired with near-light irradiation, BPs/G-Rg3@PLGA shows superior controllable CPT therapy synergetic therapeutics, significantly increasing photothermal tumor ablation effectiveness. Mechanistically, heating causes rapid G-Rg3 release from the non-complex, and thermal therapy induces apoptosis, culminating in the reduction of lung cancer metastasis. Additionally, in vivo and in vitro findings support the biocompatibility of BPs/G-Rg3@PLGA. This thesis identifies a versatile BPs-based MTN for lung cancer metastasis control.

Polymeric micelles of a copolymer composed of all-trans retinoic acid, methoxy-poly(ethylene glycol), and b-poly(N-(2 hydroxypropyl) methacrylamide) as a doxorubicin-delivery platform and for combination chemotherapy in breast cancer

Delivery of combination chemotherapeutic agents to the tumor via nanovesicles has the potential for superior tumor suppression and reduced toxicity. Herein, we prepare a block copolymer (mPH-RA) composed of methoxy-poly(ethylene glycol) (mPEG), b-poly(N-(2 hydroxypropyl) methacrylamide) (pHPMA), and all-trans retinoic acid (ATRA) by conjugating ATRA to the pre-formed copolymer, mPEG-b-pHPMA(mP-b-pH). Doxorubicin-loaded micelles, Dox@mP-b-pH, and Dox@mPH-RA were characterized by determining particle size, zeta potential, % DL, EE, Dox release, hemolysis study, and by DSC. The Dox@mPH-RA micelles (mPH-RA: Dox ratios of 10:0.5-2) displayed nano-size (36-45 nm), EE. 26-74%, and DL. 2.9-5.6%. Dox@mPH-RA micelles displayed the highest penetrability and cytotoxicity than free Dox and Dox@mP-b-pH micelles in breast cancer cell lines. Dox@mPH-RA exhibited the highest induction of apoptosis (94.1 ± 3%) than Dox (52.1 ± 4.5%), and Dox@mP-b-pH (81.7 ± 3%), and arrested cells in the highest population in G2 and S phase. Dox@mPH-RA increased the t_1/2 and C_max of Dox and demonstrated improved therapeutic efficacy and highest Dox distribution to the tumor. The Dox@mPH-RA increased the levels of apoptosis markers, caspase 3, 7, Ki-67, and caused the highest DNA fragmentation. The presence of RA improved the micelles' physicochemical properties, Dox-loading ability, and the therapeutic potential in Dox@mPH-RA via the combination therapeutic strategy.