Mixed Lanthanide Oxide Nanoparticles Coated with Alginate-Polydopamine as Multifunctional Nanovehicles for Dual Modality: Targeted Imaging and Chemotherapy

Polyphenolic Nanoparticle-Modified Probiotics for Microenvironment Remodeling and Targeted Therapy of Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs) refer to multifaceted disorders in the intestinal microenvironment and microbiota homeostasis. In view of the broad bioactivity and high compatibility of polyphenols, there is considerable interest in developing a polyphenol-based collaborative platform to remodel the IBD microenvironment and regulate microbiota. Here, we demonstrated the coordination assembly of nanostructured polyphenols to modify probiotics and simultaneously deliver drugs for IBD treatment. Inspired by the distinctive structure of tannic acid (TA), we fabricated nanostructured pBDT-TA by using a self-polymerizable aromatic dithiol (BDT) and TA, which exhibited excellent antioxidant and anti-inflammatory capability in vitro. We thus coated pBDT-TA and sodium alginate (SA) to the surface of Escherichia coli Nissle 1917 layer by layer to construct the collaborative platform EcN@SA-pBDT-TA. The modified probiotics showed improved resistance to oxidative and inflammatory stress, which resulted in superior colon accumulation and retention in IBD model mice. Further, EcN@SA-pBDT-TA could alleviate dextran sulfate sodium (DSS)-induced colitis by controlling the inflammatory response, repairing intestinal barriers, and modulating gut microbiota. Importantly, EcN@SA-pBDT-TA-mediated IBD drug delivery could achieve an improved therapeutic effect in DSS model mice. Given the availability and functionality of polyphenol and prebiotics, we expected that nanostructured polyphenol-modified probiotics provided a solution to develop a collaborative platform for IBD treatment.

Multifunctional thermosensitive hydrogel based on alginate and P(NIPAM-co-HEMIN) composites for accelerated diabetic wound healing

Non-healing wounds in patients with diabetes are a concerning issue associated with amputation and a high mortality rate. These wounds are exacerbated by oxidative stress and microbial infections resulting from hyperglycemia. Therefore, advanced materials for repairing wound beds must be identified urgently. This paper introduces a topically applicable composite hydrogel with thermosensitive properties and presents the antibacterial and antioxidant activities in mice with diabetes-induced wounds. This composite is developed by combining poly N-isopropyl acrylamide (NIPAM)-copolymerized HEMIN (NIPAM-co-HEMIN) and amine-modified alginate (ALG-EDA) biomaterials, with Ag nanoparticles (AgNPs) incorporated into the system as an antibacterial agent. Results of antibacterial tests show that the p(NIPAM-co-HEMIN)/ALG-EDA/AgNP composite system is effective against E. coli and S. aureus. Additionally, the AgNP composite exhibits low cellular toxicity in NIH3T3 and CT-2A cell lines. The wounds in diabetic mice treated with the composite system healed in <12 days, and the composite system accelerated the healing process by increasing collagen synthesis. In conclusion, the biocomposite reported herein is highly promising for repairing diabetic skin wounds and treating infections caused by bacterial microbes.

Silver sulfide coated alginate radioenhancer for enhanced X-ray radiation therapy of breast cancer

A wide range of high-Z nanomaterials are fabricated to decrease radiation dose by sensitizing cells to irradiation through various mechanisms such as ROS generation enhancement. Alginate-coated silver sulfide nanoparticles (Ag₂S@Alg) were synthesized and characterized by SEM, TEM, DLS, XRD, EPS, FT-IR, and UV-vis analysis techniques. Cytotoxicity of nanoparticles was tested against HFF-2, MCF-7, and 4 T1 cell lines for biocompatibility and radio enhancement ability evaluation, respectively. Moreover, the hemolysis assay demonstrated that the nanoparticles were biocompatible and nontoxic. In vitro intracellular ROS generation and calcein AM/PI co-staining unveiled cancerous cell death induction by nanoradiosensitizer, Ag₂S@Alg. Further, histopathology results emphasized the tumor ablation capability of Ag₂S@Alg. Silver anticancer properties were also recognized and combined with its radiosensitizing effect under X-ray irradiation.

Folic-acid adorned alginate-polydopamine modified paclitaxel/Zn-CuO nanocomplex for pH triggered drug release and synergistic antitumor efficacy

Targeted chemotherapy is a prominent cancer treatment research trend that intends to boost the efficacy of drug delivery to cancer cells. The present work aimed to design, a folate-decorated biologically inspired alginate-polydopamine capped zinc doped copper oxide nanoparticles (Zn-CuO) loaded with paclitaxel (Zn-CuO@PTX/AlgPDA-FA) as a simple, efficient, and versatile nanoplatform. Interestingly, Zn species doped in CuO frameworks significantly improved paclitaxel (PTX) molecule loading efficiency without requiring any additional functionalization and fostered the increased antitumor efficacy by precisely delivering them in tumor's acidic microenvironment by obliterating the formed coordination connections between the host as well as guest species. According to DLS, average size of nanocomplex was 196 ± 5.01 nm with ȥ-potential -31.4 ± 1.54 mV. PTX encapsulation and loading efficiencies were 75.2 ± 1.54 % and 18.54 ± 2.31 %, respectively. Furthermore, nanocomplex demonstrates high stability and biocompatibility in vitro. Under an acidic environment (pH 5.0), there was greater PTX release compared to normal physiological conditions. Moreover, Zn-CuO@PTX/AlgPDA-FA NPs showed remarkable internalization efficiency in MCF-7 cells and demonstrated strong cytotoxicity with IC₅₀ (150 ± 2.58 μg/mL) along with improved ROS generation and changed mitochondrial membrane potential level. Therefore, our approach could suggest excellent potential for tumor targeting in cancer therapy with reduced off-target toxicity, and desirable therapeutic effects.

Review on Metal-Based Theranostic Nanoparticles for Cancer Therapy and Imaging

Theranostic agents are promising due to their ability to diagnose, treat and monitor different types of cancer using a variety of imaging modalities. The advantage specifically of nanoparticles is that they can accumulate easily at the tumor site due to the large gaps in blood vessels near tumors. Such high concentration of theranostic agents at the target site can lead to enhancement in both imaging and therapy. This article provides an overview of nanoparticles that have been used for cancer theranostics, and the different imaging, treatment options and signaling pathways that are important when using nanoparticles for cancer theranostics. In particular, nanoparticles made of metal elements are emphasized due to their wide applications in cancer theranostics. One important aspect discussed is the ability to combine different types of metals in one nanoplatform for use as multimodal imaging and therapeutic agents for cancer.

Multi-Stimuli-Responsive Janus Hollow Polydopamine Nanotubes

A tubular-shaped Janus nanoparticle based on polydopamine that responds to near-infrared, magnetic, and pH stimuli is reported. The robust tubular polydopamine structure was obtained by optimizing the halloysite template-to-dopamine ratio during synthesis. The inner and outer surfaces of the tube were exposed at different steps of the template-sonication--etching process, enabling the differential surface modification of these surfaces. Poly(ethylene glycol) (PEG) and poly(N-isopropylacrylamide) (PNIPAM) were grafted to the outer and inner surface of the nanotube, respectively. The PEG-coated surface limited aggregation of the nanoparticles at elevated temperatures. The PNIPAM-coated interior enhanced doxorubicin loading and endowed the nanoparticle with temperature-responsive behavior. The deposition of precipitated Fe₃O₄ nanoparticles further modified the nanoparticles. The resulting magnetic Janus nanoparticles responded to pH, temperature, and magnetic fields. Temperature changes could be induced by near-infrared laser, and all three stimuli were found to influence release rates of adsorbed doxorubicin from the nanoparticles. The interaction of the stimuli on release kinetics was elucidated using a linear mixed model; reduced pH and NIR irradiation enhanced release while applying a static magnetic field retarded release. Furthermore, the mechanism was shifted toward Fickian behavior by applying a static magnetic field and low pH conditions. However, NIR irradiation only shifted the behavior toward Fickian behavior at low pH.

Polydopamine-modified ZIF-8 nanoparticles as a drug carrier for combined chemo-photothermal osteosarcoma therapy

Single chemotherapy often causes severe adverse effects and chemoresistance which limits therapeutic efficacy. Recently, combination of chemotherapy with photothermal therapy (PTT) have received broad attention for synergistic treatment of osteosarcoma, ultimately resulting in the enhancement of therapeutic efficacy of anticancer drugs. In this study, we have developed a novel drug delivery system based on polydopamine (pDA)-modified ZIF-8 nanoparticles loaded with methotrexate (MTX) (pDA/MTX@ZIF-8 NPs). Herein, pDA modification avoided the explosive release of the drug, and improved the biocompatibility and near-infrared (NIR) light absorbance performance of nanoparticles. The as-prepared pDA/MTX@ZIF-8 NPs could be used as drug targeting delivery system and simultaneously displayed excellent photothermal effects under NIR irradiation. Biology assays in vitro indicated that the pDA/MTX@ZIF-8 NPs were able to efficiently induce MG63 cell apoptosis through reducing mitochondrial membrane potentials (MMPs), and the introduction of photothermal agents enhanced the antitumor effect and decreased the dose of chemotherapeutic drugs. Moreover, the optimized pDA/MTX@ZIF-8 NPs (40 μg/mL) exhibited better photothermal conversion performance and facilitated tumor cells death. These results triumphantly exhibit that the pDA/MTX@ZIF-8 NPs have a synergistic effect of chemo-photothermal therapy (combination index CI = 0.346) and excellent biocompatibility, which has unexceptionable prospects for the therapy of osteosarcoma.

pH/redox-responsive core cross-linked based prodrug micelle for enhancing micellar stability and controlling delivery of chemo drugs: An effective combination drug delivery platform for cancer therapy

Core-crosslinking of micelles (CCMs) appears to be a favorable strategy to enhance micellar stability and sustained release of the loaded drug. In this study, the DOX-conjugated pH-sensitive polymeric prodrug Methoxy Poly (ethylene oxide)-b-Poly (Aspartate-Hydrazide) (mPEG-P [Asp-(Hyd-DOX)] was created using ring-opening polymerization. To further enhance the micellar system, 3,3'-diselanediyldipropanoic acid (DSeDPA) was applied to link the hydrophobic segment via click reaction to form pH/redox-responsive CCMs. Dual anti-cancer drugs, DOX as a pro-drug and SN-38 as a targeting drug, were used to enhance inhibition. DLS confirmed that the non-cross-linked micelle (NCMs) showed a higher (96.43 nm) particle size compared to the CCMs (72.63 nm). Due to micellar shrinkage after crosslinking, CCMs displayed SN-38 drug loading (7.32 %) and encapsulation efficiency (86.23 %). The mPEG-P(Asp-Hyd) copolymer's in vitro cytotoxicity on HeLa and HaCaT cell lines found that 84.52 % of the cells are alive, and zebrafish (Danio rerio) embryos and larvae are highly biocompatible. The DOX/SN-38@CCMs had a sustained discharge profile in vitro, unlike the DOX/SN-38@NCMs. In DOX/SN-38@CCMs, HeLa cells were inhibited 50.90 % more than HaCaT (14.25 %) at the maximum drug dose (10 μg/mL). The CCMs successfully targeted and supplied DOX/SN-38 in HeLa cells rather than HaCaT cells, based on cellular uptake of 2D cell culture. CCMs, unlike NCMs, inhibit the growth of spheroids for extended periods of time due to the prolonged release of the loaded drug. Overall, CCMs are good-looking for use as regulated delivery of DOX/SN-38 in cancer cells because of all of these appealing characteristics.

Synthesis, Characterization, Anti-Cancer Analysis of Sr0.5Ba0.5DyxSmxFe8-2xO19 (0.00 ≤ x ≤ 1.0) Microsphere Nanocomposites

There is enormous interest in combining two or more nanoparticles for various biomedical applications, especially in anti-cancer agent delivery. In this study, the microsphere nanoparticles were prepared (MSNPs) and their impact on cancer cells was examined. The MSNPs were prepared by using the hydrothermal method where strontium (Sr), barium (Ba), dysprosium (Dy), samarium (Sm), and iron oxide (Fe_8−2xO₁₉) were combined, and dysprosium (Dy) and samarium (Sm) was substituted with strontium (Sr) and barium (Ba), preparing Sr_0.5Ba_0.5Dy_xSm_xFe_8−2xO₁₉ (0.00 ≤ x ≤ 1.0) MSNPs. The microspheres were characterized by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) techniques. The diffraction pattern of nanohexaferrites (NHFs) reflected the signature peaks of the hexagonal structure. The XRD revealed a pure hexagonal structure without any undesired phase, which indicated the homogeneity of the products. The crystal size of the nanoparticles were in the range of 22 to 36 nm by Scherrer’s equation. The SEM of MSNPs showed a semi-spherical shape with a high degree of aggregation. TEM and HR-TEM images of MSNPs verified the spherical shape morphology and structure that approved an M-type hexaferrite formation. The anti-cancer activity was examined on HCT-116 (human colorectal carcinoma) and HeLa (cervical cancer cells) using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and post-48 h treatment of MSNPs caused a dose-dependent inhibition of HCT-116 and HeLa cell proliferation and growth. Conversely, no significant cytotoxic effect was observed on HEK-293 cells. The treatments of MSNPs also induced cancer cells DNA disintegration, as revealed by 4′,6-diamidino-2-phenylindole (DAPI) staining. Finally, these findings suggest that synthesized MSNPs possess potential inhibitory actions on cancerous cells without harming normal cells.

Europium(iii)-containing nanohydrogels for cellular imaging and drug delivery applications

By employing the excellent luminescence of Eu(iii) complexes and the versatility of nanohydrogels, Eu(iii)-containing nanohydrogels were prepared as a potential theranostic nanoplatform for cancer therapy.

Bioinspired Composite, pH-Responsive Sodium Deoxycholate Hydrogel and Generation 4.5 Poly(amidoamine) Dendrimer Improves Cancer Treatment Efficacy via Doxorubicin and Resveratrol Co-Delivery

Maximizing the antitumor efficacy of doxorubicin (DOX) with a new drug delivery strategy is always desired in the field of biomedical science. Because the clinical applications of DOX in the treatment of cancer is limited by the side effects related to the dose. Herein, we report the co-loading of DOX and resveratrol (RESV) using an injectable in situ formed sodium deoxycholate hydrogel (Na-DOC-hyd) at the pH of the tumor extracellular microenvironment. The sequential, controlled, and sustained release of RESV and DOX for synergistic antitumor effects was confirmed by entrapping G4.5-DOX in the RESV-loaded Na-DOC hydrogel (Na-DOC-hyd-RESV). The synergistic antitumor activity of Na-DOC-hyd-RESV+G4.5-DOX was assessed on HeLa cell xenograft tumor in BALB/c nude mice. In the MTT biocompatibility assay, both the G4.5 PAMAM dendrimer and Na-DOC-hyd exhibited negligible cytotoxicity up to the highest dose of 2.0 mg mL-1 in HeLa, MDA-MB-231, and HaCaT cells. The release profiles of DOX and RESV from the Na-DOC-hyd-RESV+G4.5-DOX confirmed the relatively rapid release of RESV (70.43 ± 1.39%), followed by that of DOX (54.58 ± 0.62%) at pH 6.5 in the 7 days of drug release studies. A single intratumoral injection of Na-DOC-hyd-RESV+G4.5-DOX maximally suppressed tumor growth during the 28 days of the treatment period. Na-DOC-hyd-RESV+G4.5-DOX did not cause any histological damage in the major visceral organs. Therefore, this Na-DOC-hydrogel for dual drugs (DOX and RESV) delivery at the pH of the tumor extracellular microenvironment is a promising, safe, and effective combination for antitumor chemotherapy.

Opportunities for Persistent Luminescent Nanoparticles in Luminescence Imaging of Biological Systems and Photodynamic Therapy

The use of luminescence in biological systems allows us to diagnose diseases and understand cellular processes. Persistent luminescent materials have emerged as an attractive system for application in luminescence imaging of biological systems; the afterglow emission grants background-free luminescence imaging, there is no need for continuous excitation to avoid tissue and cell damage due to the continuous light exposure, and they also circumvent the depth penetration issue caused by excitation in the UV-Vis. This review aims to provide a background in luminescence imaging of biological systems, persistent luminescence, and synthetic methods for obtaining persistent luminescent materials, and discuss selected examples of recent literature on the applications of persistent luminescent materials in luminescence imaging of biological systems and photodynamic therapy. Finally, the challenges and future directions, pointing to the development of compounds capable of executing multiple functions and light in regions where tissues and cells have low absorption, will be discussed.

Amino acid-modified PAMAM dendritic nanocarriers as effective chemotherapeutic drug vehicles in cancer treatment: a study using zebrafish as a cancer model

The use of nanomaterials for drug delivery offers many advantages including the targeted delivery of drugs and their controlled release. Nonetheless, entry into the target cells remains a challenge for many nanomaterials used for drug delivery. Moreover, cellular uptake limits the therapeutic efficiency of many anticancer drugs. An important goal is to increase the specific accumulation of these nanoparticles (NPs) at the desired cancerous tissues. Notably, cancer cells show a high demand for some amino acids and we have used this knowledge to develop novel carrier systems. In this study, drug carriers were produced by the conjugation of multiple amino acids such as l-histidine (H) and l-cysteine (C) or single amino acids such as only H with the G4.5 dendrimers (G) to produce GHC aggregates and GH NP carriers, respectively. Doxorubicin was loaded into the G4.5, GH, and GHC dendrimers (G/DOX, GH/DOX and GHC/DOX, respectively) and the release mechanism was demonstrated at pH 7.4 and pH 5.0. GH/DOX and GHC/DOX showed better stability under physiological conditions than the dendrimer alone (G/DOX). GH/DOX and GHC/DOX exhibited higher inhibition of HeLa cell proliferation in in vitro and in vivo studies in zebrafish, confirming the early release of DOX by disrupting the endosomal membrane and triggering the destabilization of carriers at a lower pH of 5.0.

Biotin-Decorated PAMAM G4.5 Dendrimer Nanoparticles to Enhance the Delivery, Anti-Proliferative, and Apoptotic Effects of Chemotherapeutic Drug in Cancer Cells

Biotin receptors are overexpressed by various types of solid cancer cells and play a significant role in tumor metabolism, growth, and metastasis. Thus, targeting the biotin receptors on tumor cells may enhance the efficiency and reduce the side-effects of chemotherapy. The aim of this study was to develop a biotin-coupled poly(amido)amine (PAMAM) (PG4.5) dendrimer nanoparticle to enhance the tumor-specific delivery and intracellular uptake of anticancer drugs via receptor-mediated endocytosis. We modified PG4.5 with diethylenetriamine (DETA) followed by biotin via an amide bond and characterized the resulting PG4.5-DETA-biotin nanoparticles by 1H NMR, FTIR, and Raman spectroscopy. Loading and releasing of gemcitabine (GEM) from PG4.5-DETA-biotin were evaluated by UV-Visible spectrophotometry. Cell viability and cellular uptake were examined by MTT assay and flow cytometry to assess the biocompatibility, cellular internalization efficiency and antiproliferative activity of PG4.5-DETA-biotin/GEM. Gemcitabine-loaded PG4.5-DETA-biotin nanoparticles were spherical with a particle size of 81.6 ± 6.08 nm and zeta potential of 0.47 ± 1.25 mV. Maximum drug-loading content and encapsulation efficiency were 10.84 ± 0.16% and 47.01 ± 0.71%, respectively. Nearly 60.54 ± 1.99% and 73.96 ± 1.14% of gemcitabine was released from PG4.5-DETA-biotin/GEM nanoparticles after 48 h at the acidic pH values of 6.5 and 5, respectively. Flow cytometry and fluorescence microscopy of cellular uptake results revealed PG4.5-DETA-biotin/GEM nanoparticles selectively targeted cancer cells in vitro. Cytotoxicity assays demonstrated gemcitabine-loaded PG4.5-DETA-biotin significantly reduced cell viability and induced apoptosis in HeLa cells. Thus, biotin-coupled PG4.5-DETA nanocarrier could provide an effective, targeted drug delivery system and selectively convey gemcitabine into tumor cells.

Recent Advances in Luminescence Imaging of Biological Systems Using Lanthanide(III) Luminescent Complexes

The use of luminescence in biological systems allows one to diagnose diseases and understand cellular processes. Molecular systems, particularly lanthanide(III) complexes, have emerged as an attractive system for application in cellular luminescence imaging due to their long emission lifetimes, high brightness, possibility of controlling the spectroscopic properties at the molecular level, and tailoring of the ligand structure that adds sensing and therapeutic capabilities. This review aims to provide a background in luminescence imaging and lanthanide spectroscopy and discuss selected examples from the recent literature on lanthanide(III) luminescent complexes in cellular luminescence imaging, published in the period 2016-2020. Finally, the challenges and future directions that are pointing for the development of compounds that are capable of executing multiple functions and the use of light in regions where tissues and cells have low absorption will be discussed.