Functionalization of Biomimetic Polydopamine Shells Constructed onto Bismuth-Core Particles for pH-Mediated Drug Targeting to Heal Bacterial Infections

Nonhealing chronic bacterial infections are very challenging to both patients and the healthcare-providing system. Multimodal therapy enhances the antibiotic efficacy to treat infections via combating multidrug resistance through cumulative therapeutic effects. Functionalized polydopamine (PDA)-coated Bi particles having a core-shell structure may treat such chronic infections. We fabricated a new advanced material based on Tris-functionalized PDA and Bi using a facile three-step protocol for healing drug-resistant bacterial infections. The fabrication of Bi particles, PDA coating on Bi particles, and their Tris functionalization were confirmed by X-ray diffraction, and spectroscopic and thermogravimetric analyses. Tris-functionalized PDA-coated Bi particles, abbreviated as Bi/PDA-Tris, exhibited a higher average diameter, improved hydrophilicity, aqueous dispersity, and colloidal stability. Bi/PDA-Tris showed a delicate surface morphology, narrow size distribution, spherical shape, and core-shell structure. In vitro bovine serum albumin and hemolysis assays showed minimal protein adsorption and the desirable hemocompatibility of Bi/PDA-Tris. Antibacterial gentamicin (GM)-immobilized Bi/PDA-Tris showed pH-mediated sustained drug release kinetics under acidic conditions. The in vitro study of GM-loaded Bi/PDA-Tris particles exhibited significant bacterial growth inhibition and bactericidal activity. Tris functionalization effectively enhances the antibacterial efficacy of the PDA shell under acidic conditions to target and heal bacterial infections. This approach has introduced economic, nontoxic, easy-to-use, relatively more biocompatible Bi particles as a substituent for precise metals like Pt, Au, and Ag for the development of core-shell composite materials.

In situ formation of alginic acid-gold nanohybrids for application in cancer photothermal therapy

Gold-based nanoparticles present excellent optical properties that propelled their widespread application in biomedicine, from bioimaging to photothermal applications. Nevertheless, commonly employed manufacturing methods for gold-based nanoparticles require long periods and laborious protocols that reduce cost-effectiveness and scalability. Herein, a novel methodology was used for producing gold-alginic acid nanohybrids (Au-Alg-NH) with photothermal capabilities. This was accomplished by promoting the in situ reduction and nucleation of gold ions throughout a matrix of alginic acid by using ascorbic acid. The results obtained reveal that the Au-Alg-NHs present a uniform size distribution and a spike-like shape. Moreover, the nanomaterials were capable to mediate a temperature increase of ≈11°C in response to the irradiation with a near-infrared region (NIR) laser (808 nm, 1.7 W cm-2 ). The in vitro assays showed that Au-Alg-NHs were able to perform a NIR light-triggered ablation of cancer cells (MCF-7), being observed a reduction in the cell viability to ≈27%. Therefore, the results demonstrate that this novel methodology holds the potential for producing Au-Alg-NH with photothermal capacity and higher translatability to the clinical practice, namely for cancer therapy.

Gold@mesoporous polydopamine nanoparticles modified self-healing hydrogel for sport-injuring therapy

Sports-related damage is a prevalent issue, which a combination therapy including photothermal irradiation, self-healing dressing and antibacterial treatment is an effective way to rehabilitate it. In the study, a multifunctional hydrogel was developed to meet the requirement. Firstly, mesoporous polydopamine (MPDA) was prepared, where gold nanoparticles (Au NPs) were formed in its mesoporous structure, to construct Au@MPDA NPs with nanosize about 200 nm. Synergetic and efficient photothermal effect was achieved by the combination of the two photothermal agents. The Au@MPDA NPs were then added to modify polyvinyl alcohol-carboxymethyl chitosan-borax (PCB) hydrogel. Via rheological property characterization, cell experiments and antibacterial evaluation, high photothermal efficiency and effective antibacterial activity of Au@MPDA@PCB hydrogel was obtained with the aid of Au@MPDA NPs, together with self-healing property. When treated in motion-related tissue, the modified hydrogel showed excellent adaptive property and photothermal effect in situ. This study is beneficial for developing a novel rehabilitation treatment strategy for sports-related injuries.

Polydopamine-containing nano-systems for cancer multi-mode diagnoses and therapies: A review

Polydopamine (PDA) has fascinating properties such as inherent biocompatibility, simple preparation, strong near-infrared absorption, high photothermal conversion efficiency, and strong metal ion chelation, which have catalyzed extensive research in PDA-containing multifunctional nano-systems particularly for biomedical applications. Thus, it is imperative to overview synthetic strategies of various PDA-containing nanoparticles (NPs) for state-of-the-art cancer multi-mode diagnoses and therapies applications, and offer a timely and comprehensive summary. In this review, we will focus on the synthetic approaches of PDA NPs, and summarize the construction strategies of PDA-containing NPs with different structure forms. Additionally, the application of PDA-containing NPs in bioimaging such as photoacoustic imaging, fluorescence imaging, magnetic resonance imaging and other imaging modalities will be reviewed. We will especially offer an overview of their therapeutic applications in tumor chemotherapy, photothermal therapy, photodynamic therapy, photocatalytic therapy, sonodynamic therapy, radionuclide therapy, gene therapy, immunotherapy and combination therapy. At the end, the current trends, limitations and future prospects of PDA-containing nano-systems will be discussed. This review aims to provide guidelines for new scientists in the field of how to design PDA-containing NPs and what has been achieved in this area, while offering comprehensive insights into the potential of PDA-containing nano-systems used in cancer diagnosis and treatment.

Cobalt Ferrite-Gossypol Coordination Nanoagents with High Photothermal Conversion Efficiency Sensitizing Chemotherapy against Bcl-2 to Induce Tumor Apoptosis

Gossypol is a chemotherapeutic drug that can inhibit the anti-apoptotic protein Bcl-2, but the existing gossypol-related nanocarriers cannot well solve the problem of chemotherapy resistance. Based on the observation that gossypol becomes black upon Fe3+ coordination, it is hypothesized that encasing gossypol in glyceryl monooleate (GMO) and making it coordinate cobalt ferrite will not only improve its photothermal conversion efficiency (PCE) but also help it enter tumor cells. As the drug loading content and drug encapsulation efficiency of gossypol are 10.67% (w/w) and 96.20%, the PCE of cobalt ferrite rises from 14.71% to 36.00%. The synergistic therapeutic effect finally induces tumor apoptosis with a tumor inhibition rate of 96.56%, which is 2.99 and 1.47 times higher than chemotherapy or photothermal therapy (PTT) alone. PTT generated by the GMO nanocarriers under the irradiation of 808 nm laser can weaken tumor hypoxia, thereby assisting gossypol to inhibit Bcl-2. In addition, the efficacy of nanocarriers is also evaluated through T2 -weighted magnetic resonance imaging. Observations of gossypol-induced apoptosis in tissue slices provide definitive proof of chemotherapy sensitization, indicating that such coordination nanocarriers can be used as an effective preclinical agent to enhance chemotherapy.

Development of an Au nanoclusters based activatable nanoprobe for NIR-II fluorescence imaging of gastric acid

Gastric acid is an important functional substance secreted by the stomach of the living organisms, reflecting the gastric physiological condition. The sensing of gastric acid in vivo is of great significance for evaluation of gastric function, diagnosis and treatment of gastric diseases and maintenance of organism health but remains challenging due to the harsh acid and digestive environment of stomach. This study developed an activatable nanoprobe based on Au nanoclusters (Au NCs) for sensitive and real-time noninvasive near-infrared II (NIR-II) fluorescence imaging detection of gastric acid in vivo for the first time. The Au NCs were encapsulated by polydopamine to have enhanced NIR-II luminescence and high stability and combined with methylene blue to possess the pH responsiveness for gastric acid imaging. The developed nanoprobe could not only monitor gastric acid secretion in vivo but also imaging the changes of gastric acid caused by feeding, acid-inhibition drugs and gastric ulcer disease. This study provides a promising avenue for the improvement of the application performance of Au NCs and imaging analysis of gastric acid and related gastric diseases.

Multifunctional Plasmon-Tunable Au Nanostars and Their Applications in Highly Efficient Photothermal Inactivation and Ultra-Sensitive SERS Detection

The development and application in different fields of multifunctional plasmonic nanoparticles (NPs) have always been research hotspots. Herein, multi-tip Au nanostars (NSs) with an anisotropic structure were fabricated for the photothermal therapy (PTT) of bacteria and surface-enhanced Raman scattering (SERS) detection of pollutants. The size and localized surface plasmon resonance (LSPR) characteristics of Au NSs were adjusted by varying Au seed additions. In addition, photothermal conversion performance of Au NSs with various Au seed additions was evaluated. Photothermal conversion efficiency of Au NSs with optimal Au seed additions (50 μL) was as high as 28.75% under 808 nm laser irradiation, and the heat generated was sufficient to kill Staphylococcus aureus (S. aureus). Importantly, Au NSs also exhibited excellent SERS activity for the 4-mercaptobenzoic acid (4-MBA) probe molecule, and the local electromagnetic field distribution of Au NSs was explored through finite-difference time-domain (FDTD) simulation. As verified by experiments, Au NSs' SERS substrate could achieve a highly sensitive detection of a low concentration of potentially toxic pollutants such as methylene blue (MB) and bilirubin (BR). This work demonstrates a promising multifunctional nanoplatform with great potential for efficient photothermal inactivation and ultra-sensitive SERS detection.

A guanosine-based hydrogel integrating photothermal effect of PDAAuNPs through dynamic borate bond for photothermal therapy of cancer

Photothermal therapy (PTT) has drawn extensive attention owing to its noninvasive and great tissue penetration depth. However, the physical encapsulation of photothermal agents may lead to their rapid release. Dual-functional hydrogel systems that integrate functions and carriers can potentially solve this problem. In this work, we successfully developed a dual-functional guanosine(G)-based hydrogel integrating the photothermal effect and localized delivery by introducing dynamic borate ester utilizing the photothermal property of PDA-AuNPs and the self-assembly ability of G. Both in vitro and in vivo results confirmed that the GBPA hydrogel not only exhibited excellent photothermal toxicity, stability, injectability, and biocompatibility, but also possessed high photothermal antitumor activity. These results suggested that the GBPA hydrogel could be used as a dual-functional hydrogel integrating photothermal effect and localized delivery in one system, which would possibly provide a new opportunity for the design of new dual-functional hydrogels for highly efficient cancer therapy.

Gold nanostar‐based complexes applied for cancer theranostics

Cancer remains a major health problem that plagues human beings, calling widespread attention to develop novel theranostics to achieve sensitive diagnosis and efficient therapy. Multifunctional nanomedicine that can integrate diagnosis with treatment formulations has been emerging as a powerful strategy to overcome the current drawbacks in conventional clinical cancer treatments. Due to the good biocompatibility, easy surface modification, surface‐enhanced Raman spectroscopy (SERS)/computed tomography (CT)/photoacoustic (PA) imaging properties, and exceptional photothermal performance of gold nanostars (AuNSs), various AuNS‐based complexes or nanohybrids including metal compound/AuNSs, SiO2/AuNSs, polymer/AuNSs, and dendrimer/AuNSs, and so forth have been developed, holding great blueprint in cancer theranostics. Herein, we concisely review the recent progresses in the intriguing design of AuNS‐based nanoplatforms, and their applications in bioimaging, therapy and imaging‐guided cancer treatment, and clarify the possible future perspectives for the design of AuNS‐facilitated cancer theranostics.

Advances and Potentials of Polydopamine Nanosystem in Photothermal-Based Antibacterial Infection Therapies

Bacterial infection remains one of the most dangerous threats to human health due to the increasing cases of bacterial resistance, which is caused by the extensive use of current antibiotics. Photothermal therapy (PTT) is similar to photodynamic therapy (PDT), but PTT can generate heat energy under the excitation of light of specific wavelength, resulting in overheating and damage to target cells or sites. Polydopamine (PDA) has been proved to show plenty of advantages, such as simple preparation, good photothermal conversion effects, high biocompatibility, and easy functionalization and adhesion. Taking these advantages, dopamine is widely used to synthesize the PDA nanosystem with excellent photothermal effects, good biocompatibility, and high drug loading ability, which therefore play more and more important roles for anticancer and antibacterial treatment. PDA nanosystem-mediated PTT has been reported to induce significant tumor inhibition, as well as bacterial killings due to PTT-induced hyperthermia. Moreover, combined with other cancer or bacterial inhibition strategies, PDA nanosystem-mediated PTT can achieve more effective tumor and bacterial inhibitions. In this review, we summarized the progress of preparation methods for the PDA nanosystem, followed by advances of their biological functions and mechanisms for PTT uses, especially in the field of antibacterial treatments. We also provided advances on how to combine PDA nanosystem-mediated PTT with other antibacterial methods for synergistic bacterial killings. Moreover, we further provide some prospects of PDA nanosystem-mediated PTT against intracellular bacteria, which might be helpful to facilitate their future research progress for antibacterial therapy.

Injectable nanocomposite hydrogels as an emerging platform for biomedical applications: A review

Hydrogels have attracted much attention for biomedical and pharmaceutical applications due to the similarity of their biomimetic structure to the extracellular matrix of natural living tissues, tunable soft porous microarchitecture, superb biomechanical properties, proper biocompatibility, etc. Injectable hydrogels are an exciting type of hydrogels that can be easily injected into the target sites using needles or catheters in a minimally invasive manner. The more comfortable use, less pain, faster recovery period, lower costs, and fewer side effects make injectable hydrogels more attractive to both patients and clinicians in comparison to non-injectable hydrogels. However, it is difficult to achieve an ideal injectable hydrogel using just a single material (i.e., polymer). This challenge can be overcome by incorporating nanofillers into the polymeric matrix to engineer injectable nanocomposite hydrogels with combined or synergistic properties gained from the constituents. This work aims to critically review injectable nanocomposite hydrogels, their preparation methods, properties, functionalities, and versatile biomedical and pharmaceutical applications such as tissue engineering, drug delivery, and cancer labeling and therapy. The most common natural and synthetic polymers as matrices together with the most popular nanomaterials as reinforcements, including nanoceramics, carbon-based nanostructures, metallic nanomaterials, and various nanosized polymeric materials, are highlighted in this review.

Dendrimer-modified gold nanorods as a platform for combinational gene therapy and photothermal therapy of tumors

Background

The exploitation of novel nanomaterials combining diagnostic and therapeutic functionalities within one single nanoplatform is challenging for tumor theranostics.

Methods

We synthesized dendrimer-modified gold nanorods for combinational gene therapy and photothermal therapy (PTT) of colon cancer. Poly(amidoamine) dendrimers (PAMAM, G3) grafted gold nanorods were modified with GX1 peptide (a cyclic 7-mer peptide, CGNSNPKSC). The obtained Au NR@PAMAM-GX1 are proposed as a gene delivery vector to gene (FAM172A, regulates the proliferation and apoptosis of colon cancer cells) for the combination of photothermal therapy (PTT) and gene therapy of Colon cancer cells (HCT-8 cells). In addition, the CT imaging function of Au NR can provide imaging evidence for the diagnosis of colon cancer.

Results

The results display that Au NR@PAMAM-GX1 can specifically deliver FAM172A to cancer cells with excellent transfection efficiency. The HCT-8 cells treated with the Au NR@PAMAM-GX1/FAM172A under laser irradiation have a viability of 20.45%, which is much lower than the survival rate of other single-mode PTT treatment or single-mode gene therapy. Furthermore, animal experiment results confirm that Au NR@PAMAM-GX1/FAM172A complexes can achieve tumor thermal imaging, targeted CT imaging, PTT and gene therapy after tail vein injection.

Conclusion

Our findings demonstrate that the synthesized Au NR@PAMAM-GX1 offer a facile platform to exert antitumor and improve the diagnostic level of tumor.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02105-3.

A pH-targeted and NIR-responsive NaCl-nanocarrier for photothermal therapy and ion-interference therapy

Transport ions into cells through nanocarrier to achieve ion-interference therapy provides new inspiration for cancer treatment. In this work, a pH-targeted and NIR-responsive NaCl-nanocarrier is prepared using surfactant Vitamin E-O(EG₂-Glu) and modified with polydopamine (PDA) and pH-sensitive zwitterionic chitosan (ZWC). The NaCl-nanocarrier is decorated with NH₄HCO₃ and IR-780 to introduce near-infrared (NIR)-responsive performance and imaging. Once the NaCl-nanocarrier is exposed to NIR laser, the temperature rises rapidly because of the excellent photothermal conversion ability of PDA, then NH₄HCO₃ is decomposed into NH₃ and CO₂, which burst the nanocarrier, resulting in Cl^- and Na⁺ "bomb-like" release. This pH-targeted nanocarrier accumulates more at tumor site and when irradiating the site with NIR light, the temperature rises and excessive Cl^- and Na⁺ are released to destroy the ion homeostasis and inhibit tumor growth effectively. Through this strategy, the unique combination of ion interference therapy and photothermal therapy is achieved.

One-pot synthesis of 68Ga-doped ultrasmall gold nanoclusters for PET/CT imaging of tumors

Gold nanoclusters (AuNCs) have attracted much attention for tumor theranostics in recent years because of their ability of renal clearance and to escape the reticuloendothelial system (RES) sequestration. In this study, we presented a novel method to synthesize ⁶⁸Ga-doped (labeled) AuNCs by simultaneous reduction of ⁶⁸GaCl₃ and HAuCl₄ by glutathione. As synthesized ⁶⁸Ga-doped, glutathione-coated AuNCs (⁶⁸Ga-GSH@AuNCs) were ultrasmall in size (<2 nm), highly stable under physiological conditions and renally clearable, and had high efficiency for tumor targeting. To demonstrate the universality of this ⁶⁸Ga labeling method and further enhance tumor targeting efficiency, arginine-glycine-aspartate (RGD)-containing peptide was introduced as co-reductant to synthesize RGD peptide and glutathione co-coated, ⁶⁸Ga-labeled AuNCs (⁶⁸Ga-RGD-GSH@AuNCs). Introduction of RGD peptide did not interfere the synthesis process but significantly enhanced the tumor targeting efficiency of the AuNCs. Our study demonstrated that it was feasible to label AuNCs with gallium-68 by direct reduction of the radioisotope and HAuCl₄ with reductant peptides, holding a great potential for clinical translation for PET/CT detection of tumors.

Integrin αvβ3-targeted polydopamine-coated gold nanostars for photothermal ablation therapy of hepatocellular carcinoma

Photothermal therapy (PTT) has emerged as a promising cancer therapeutic method. In this study, Arg-Gly-Asp (RGD) peptide-conjugated polydopamine-coated gold nanostars (Au@PDA-RGD NPs) were prepared for targeting PTT of hepatocellular carcinoma (HCC). A polydopamine (PDA) shell was coated on the surface of gold nanostars by the oxidative self-polymerization of dopamine (termed as Au@PDA NPs). Au@PDA NPs were further functionalized with polyethylene glycol and RGD peptide to improve biocompatibility as well as selectivity toward the HCC cells. Au@PDA-RGD NPs showed an intense absorption at 822 nm, which makes them suitable for near-infrared-excited PTT. Our results indicated that the Au@PDA-RGD NPs were effective for the PTT therapy of the α_Vβ₃ integrin receptor-overexpressed HepG2 cells in vitro. Further antitumor mechanism studies showed that the Au@PDA-RGD NPs-based PTT induced human liver cancer cells death via the mitochondrial–lysosomal and autophagy pathways. In vivo experiments showed that Au@PDA-RGD NPs had excellent tumor treatment efficiency and negligible side effects. Thus, our study showed that Au@PDA-RGD NPs could offer an excellent nanoplatform for PTT of HCC.

In situ synthesis of fluorescent polydopamine on biogenic MnO2 nanoparticles as stimuli responsive multifunctional theranostics

Multifunctional nanocomposites have drawn great attention in clinical applications because of their ability to integrate diagnostic and therapeutic functions. Manganese dioxide (MnO₂), owing to its biocompatibility and magnetic resonance imaging (MRI) properties, has been widely applied in biomedical research. Our previous work on biogenic MnO₂ nanoparticles (Bio-MnO₂ NPs) revealed that intrinsic photothermal properties and stimuli-responsive MRI imaging are particularly promising for the development of theranostic systems. However, further improvement in the photothermal therapy (PTT) performance of Bio-MnO₂ NPs is still required. Herein, we have improved the PTT efficiency of Bio-MnO₂ NPs by in situ synthesis of fluorescent polydopamine (PDA) while generating additional stimuli responsive fluorescence properties in this system, thus further broadening the scope of their theranostic functions. These synthesis conditions are mild and green. The fluorescence of PDA was quenched by capping Bio-MnO₂ NPs and could be recovered upon degradation of Bio-MnO₂ NPs inside tumour cells. Additionally, Mn²⁺ released from the nanoparticles can support T₁-weighted MR imaging. Compared to the Bio-MnO₂ NPs alone, the integration of Bio-MnO₂ NPs and PDA significantly enhances the photothermal performance in vitro and in vivo. With their high biocompatibility, these multifunctional composite nanodevices hold great potential for fluorescence imaging and MRI-guided photothermal therapy.

Folic Acid-Conjugated Gold Nanostars for Computed Tomography Imaging and Photothermal/Radiation Combined Therapy

Fabrication of multifunctional nanoprobes, which integrate tumor targeting, imaging, and effective treatment, has been widely explored in nanomedicine. In the present study, we fabricated tumor-targeting polymer folic acid-terminated polyethylene glycol thiol-modified gold nanostars (GNS-FA), which could realize X-ray computed tomography (CT) imaging and PTT/RT synergistic therapy. The synthesized GNS-FA exhibited good biocompatibility. GNS-FA could be used as a CT imaging contrast agent due to the strong X-ray attenuation of Au. GNS-FA exhibited good near-infrared (NIR) light absorption and excellent photothermal conversion performance, making them promising photothermal transduction agents (PTAs). Furthermore, GNS-FA could be used as an RT sensitizer to enhance the radio-mediated cell death due to the high atomic number (high Z) of gold. Hence, GNS-FA were used as the CT imaging agent, PTA, and radiosensitizer in this work. The in vitro antitumor experiments showed that the PTT/RT combined treatment had enhanced anticancer efficacy compared with the monotherapy (PTT or RT). Our results indicated that the bioconjugated GNS could offer an excellent nanoplatform for CT imaging-guided PTT/RT combined cancer therapy in the future.

Phenolic-enabled nanotechnology: versatile particle engineering for biomedicine

Phenolics are ubiquitous in nature and have gained immense research attention because of their unique physiochemical properties and widespread industrial use. In recent decades, their accessibility, versatile reactivity, and relative biocompatibility have catalysed research in phenolic-enabled nanotechnology (PEN) particularly for biomedical applications which have been a major benefactor of this emergence, as largely demonstrated by polydopamine and polyphenols. Therefore, it is imperative to overveiw the fundamental mechanisms and synthetic strategies of PEN for state-of-the-art biomedical applications and provide a timely and comprehensive summary. In this review, we will focus on the principles and strategies involved in PEN and summarize the use of the PEN synthetic toolkit for particle engineering and the bottom-up synthesis of nanohybrid materials. Specifically, we will discuss the attractive forces between phenolics and complementary structural motifs in confined particle systems to synthesize high-quality products with controllable size, shape, composition, as well as surface chemistry and function. Additionally, phenolic's numerous applications in biosensing, bioimaging, and disease treatment will be highlighted. This review aims to provide guidelines for new scientists in the field and serve as an up-to-date compilation of what has been achieved in this area, while offering expert perspectives on PEN's use in translational research.

Tumor microenvironment-activated NIR-II reagents for tumor imaging and therapy

Second near-infrared window (NIR-II, 1000-1700 nm) absorption and fluorescent agents have attracted great attention because they can overcome the penetration limitation of the first near-infrared window (NIR-I, 750-1000 nm). However, these always "on" agents face the severe problem of being susceptible to retention and phagocytosis by the reticuloendothelial system after intravenous administration, which results in signal interference during diagnosis and side effects during treatment. Accordingly, tumor microenvironment-responsive smart agents (smart NIR-II agents), whose imaging and therapeutic functions can only be triggered in tumors, can overcome this limitation. Thus, NIR-II smart agents, which exhibit a combined response to the tumor microenvironment and NIR-II, make full use of the advantages of both triggers and improve the precision diagnosis and effective treatment of cancer. This review summarizes the recent advances in tumor microenvironment-activated NIR-II agents for tumor diagnosis and treatment, including smart NIR-II fluorescence imaging, photoacoustic imaging, photothermal therapy and photodynamic therapy. Finally, the challenges and perspectives of NIR-II smart agents for tumor diagnosis and treatment are proposed.

Ce6-Conjugated and polydopamine-coated gold nanostars with enhanced photoacoustic imaging and photothermal/photodynamic therapy to inhibit lung metastasis of breast cancer

Metastasis is the main cause of treatment failure in breast cancer, and integrated phototheranostics is a promising strategy to achieve both precision theranostics and metastasis inhibition. In this work, a multifunctional phototheranostic nanoprobe composed of chlorin e6 (Ce6)-conjugated and polydopamine (PDA)-coated gold nanostars (AuNSs) was synthesized for simultaneous photoacoustic (PA) imaging, photothermal therapy (PTT) and photodynamic therapy (PDT). Under the irradiation of near infrared laser, AuNSs@PDA showed enhanced photothermal conversion and amplified PA imaging performance, compared with single AuNSs. By the covalent conjugation of Ce6, the AuNSs@PDA-Ce6 nanoprobe showed robust stability and excellent singlet oxygen (1O2) generation ability. Under the combination of PTT/PDT, the AuNSs@PDA-Ce6 nanoprobes significantly reduced the growth of 4T1 tumors and suppressed their lung metastasis. All the results demonstrated the considerable potential of AuNSs@PDA-Ce6 phototheranostic nanoprobes for precision theranostics and metastasis inhibition of breast cancer.

Strategies to improve the photothermal capacity of gold-based nanomedicines

The plasmonic photothermal properties of gold nanoparticles have been widely explored in the biomedical field to mediate a photothermal effect in response to the irradiation with an external light source. Particularly, in cancer therapy, the physicochemical properties of gold-based nanomaterials allow them to efficiently accumulate in the tumor tissue and then mediate the light-triggered thermal destruction of cancer cells with high spatial-temporal control. Nevertheless, the gold nanomaterials can be produced with different shapes, sizes, and organizations such as nanospheres, nanorods, nanocages, nanoshells, and nanoclusters. These gold nanostructures will present different plasmonic photothermal properties that can impact cancer thermal ablation. This review analyses the application of gold-based nanomaterials in cancer photothermal therapy, emphasizing the main parameters that affect its light-to-heat conversion efficiency and consequently the photothermal potential. The different shapes/organizations (clusters, shells, rods, stars, cages) of gold nanomaterials and the parameters that can be fine-tuned to improve the photothermal capacity are presented. Moreover, the gold nanostructures combination with other materials (e.g. silica, graphene, and iron oxide) or small molecules (e.g. indocyanine green and IR780) to improve the nanomaterials photothermal capacity is also overviewed.

Large-area periodic arrays of gold nanostars derived from HEPES-, DMF-, and ascorbic-acid-driven syntheses

With arms radiating from a central core, gold nanostars represent a unique and fascinating class of nanomaterials from which extraordinary plasmonic properties are derived. Despite their relevance to sensing applications, methods for fabricating homogeneous populations of nanostars on large-area planar surfaces in truly periodic arrays is lacking. Herein, the fabrication of nanostar arrays is demonstrated through the formation of hexagonal patterns of near-hemispherical gold seeds and their subsequent exposure to a liquid-state chemical environment that is conducive to colloidal nanostar formation. Three different colloidal nanostar protocols were targeted where HEPES, DMF, and ascorbic acid represent a key reagent in their respective redox chemistries. Only the DMF-driven synthesis proved readily adaptable to the substrate-based platform but nanostar-like structures emerged from the other protocols when synthetic controls such as reaction kinetics, the addition of Ag⁺ ions, and pH adjustments were applied. Because the nanostars were derived from near-hemispherical seeds, they acquired a unique geometry that resembles a conventional nanostar that has been truncated near its midsection. Simulations of plasmonic properties of this geometry reveal that such structures can exhibit maximum near-field intensities that are as much as seven-times greater than the standard nanostar geometry, a finding that is corroborated by surface-enhanced Raman scattering (SERS) measurements showing large enhancement factors. The study adds nanostars to the library of nanostructure geometries that are amenable to large-area periodic arrays and provides a potential pathway for the nanofabrication of SERS substrates with even greater enhancements.

Metal-Containing Polydopamine Nanomaterials: Catalysis, Energy, and Theranostics

Polydopamine (PDA) is a major type of artificial melanin material with many interesting properties such as antioxidant activity, free-radical scavenging, high photothermal conversion efficiency, and strong metal-ion chelation. The high affinity of PDA to a wide range of metals/metal ions has offered a new class of functional metal-containing polydopamine (MPDA) nanomaterials with promising functions and extensive applications. Understanding and controlling the metal coordination environment is vital to achieve desirable functions for which such materials can be exploited. MPDA nanomaterials with metal/metal ions as the active functions are reviewed, including their synthesis and metal coordination environment and their applications in catalysis, batteries, solar cells, capacitors, medical imaging, cancer therapy, antifouling, and antibacterial coating. The current trends, limitations, and future directions of this area are also explored.

Polydopamine-doped virus-like mesoporous silica coated reduced graphene oxide nanosheets for chemo-photothermal synergetic therapy

Multifunctional nanocarriers have been widely accepted and utilized for biomedical applications, because of their structural regularity, convenient post-modification and controllable structure and morphology. Herein, we reported polydopamine-doped virus-like mesoporous silica coated reduced graphene oxide nanosheets (rGO@PVMSNs) nanocomposites by a facile oil–water biphase stratification method. The synthesized rGO@PVMSNs nanocomposites performed excellent biocompatibility and photothermal performance. They could be employed as photoacoustic imaging contrast in vivo. Furthermore, the rGO@PVMSNs nanocarriers were used for loading the antitumor drug doxorubicin (DOX), the rGO@PVMSNs@DOX nanocomposites were also demonstrated to be with high inhibition of HepG2 cancer cells, especially with the help of near-infrared irradiation, which were more efficient than single chemotherapy or photothermal therapy. The rGO@PVMSNs@DOX nanocomposites of this work could be used as photoacoustic imaging and chemo-photothermal synergetic therapy agents, which show a new perspective for clinical tumor diagnosis and therapy.

From Bioinspired Glue to Medicine: Polydopamine as a Biomedical Material

Biological structures have emerged through millennia of evolution, and nature has fine-tuned the material properties in order to optimise the structure-function relationship. Following this paradigm, polydopamine (PDA), which was found to be crucial for the adhesion of mussels to wet surfaces, was hence initially introduced as a coating substance to increase the chemical reactivity and surface adhesion properties. Structurally, polydopamine is very similar to melanin, which is a pigment of human skin responsible for the protection of underlying skin layers by efficiently absorbing light with potentially harmful wavelengths. Recent findings have shown the subsequent release of the energy (in the form of heat) upon light excitation, presenting it as an ideal candidate for photothermal applications. Thus, polydopamine can both be used to (i) coat nanoparticle surfaces and to (ii) form capsules and ultra-small (nano)particles/nanocomposites while retaining bulk characteristics (i.e., biocompatibility, stability under UV irradiation, heat conversion, and activity during photoacoustic imaging). Due to the aforementioned properties, polydopamine-based materials have since been tested in adhesive and in energy-related as well as in a range of medical applications such as for tumour ablation, imaging, and drug delivery. In this review, we focus upon how different forms of the material can be synthesised and the use of polydopamine in biological and biomedical applications.

Gold nanostars-diagnosis, bioimaging and biomedical applications

Gold Nanostars (GNS) have attracted tremendous attention toward themselves owing to their multi-branched structure and unique properties. These state of the art metallic nanoparticles possess intrinsic features like remarkable optical properties and exceptional physiochemical activities. These star-shaped gold nanoparticles can predominantly be utilized in biosensing, photothermal therapy, imaging, surface-enhanced Raman spectroscopy and target drug delivery applications due to their low toxicity and extraordinary optical features. In the current review, recent approaches in the matter of GNS in case of diagnosis, bioimaging and biomedical applications were summarized and reported. In this regard, first an overview about the structure and general properties of GNS were reported and thence detailed information regarding the diagnostic, bioimaging, photothermal therapy, and drug delivery applications of such novel nanomaterials were presented in detail. Summarized information clearly highlighting the superior capability of GNS as potential multi-functional materials for biomedical applications.

Overview of the application of inorganic nanomaterials in cancer photothermal therapy

Cancer photothermal therapy (PTT) has captured the attention of researchers worldwide due to its localized and trigger-activated therapeutic effect.

In vivo migration of Fe3O4@polydopamine nanoparticle-labeled mesenchymal stem cells to burn injury sites and their therapeutic effects in a rat model

Mesenchymal stem cell (MSC)-based therapy has emerged as a promising therapeutic strategy for tissue regeneration and repair. However, efficient targeted delivery to specific tissues remains an open challenge. Here, we non-invasively monitored the migration of MSCs labeled with Fe3O4@polydopamine nanoparticles (Fe3O4@PDA NPs) toward laser burn injury sites in a living rat model and evaluated the effects of the labeled MSCs at the injury site. The Fe3O4@PDA NPs could be effectively incorporated into the MSCs without any negative effects on stem cell properties. Furthermore, they enhanced the migration ability of the MSCs by up-regulating the expression level of C-X-C chemokine receptor type 4 (CXCR4). They also increased the secretion of some cytokines and the expression of healing-related genes in comparison with unlabeled MSCs. Labeled MSCs were intravenously administered into injured rats, and live imaging was performed to monitor MSC migration. Fluorescent signals of the labeled MSCs appeared at burn injury lesions 1 day after injection and then gradually increased up to 7 days. After 7 days, the group injected with the labeled MSCs showed less inflammation compared with those injected with the unlabeled MSCs. Additionally, the labeled MSC group showed increased cytokines and reduced pro-inflammatory factors compared with the unlabeled MSC group. The Fe3O4@PDA NPs enhanced stromal cell-derived factor-1/CXCR4-mediated MSC migration in vivo. Thus, we demonstrated the safety, feasibility, and potential efficacy of using the Fe3O4@PDA NPs for optimizing MSC-based therapeutic strategies for burn wound healing.

Harnessing Solar-Driven Photothermal Effect toward the Water-Energy Nexus

Producing affordable freshwater has been considered as a great societal challenge, and most conventional desalination technologies are usually accompanied with large energy consumption and thus struggle with the trade-off between water and energy, i.e., the water-energy nexus. In recent decades, the fast development of state-of-the-art photothermal materials has injected new vitality into the field of freshwater production, which can effectively harness abundant and clean solar energy via the photothermal effect to fulfill the blue dream of low-energy water purification/harvesting, so as to reconcile the water-energy nexus. Driven by the opportunities offered by photothermal materials, tremendous effort has been made to exploit diverse photothermal-assisted water purification/harvesting technologies. At this stage, it is imperative and important to review the recent progress and shed light on the future trend in this multidisciplinary field. Here, a brief introduction of the fundamental mechanism and design principle of photothermal materials is presented, and the emerging photothermal applications such as photothermal-assisted water evaporation, photothermal-assisted membrane distillation, photothermal-assisted crude oil cleanup, photothermal-enhanced photocatalysis, and photothermal-assisted water harvesting from air are summarized. Finally, the unsolved challenges and future perspectives in this field are emphasized. It is envisioned that this work will help arouse future research efforts to boost the development of solar-driven low-energy water purification/harvesting.

Versatile Polydopamine Platforms: Synthesis and Promising Applications for Surface Modification and Advanced Nanomedicine

As a mussel-inspired material, polydopamine (PDA), possesses many properties, such as a simple preparation process, good biocompatibility, strong adhesive property, easy functionalization, outstanding photothermal conversion efficiency, and strong quenching effect. PDA has attracted increasingly considerable attention because it provides a simple and versatile approach to functionalize material surfaces for obtaining a variety of multifunctional nanomaterials. In this review, recent significant research developments of PDA including its synthesis and polymerization mechanism, physicochemical properties, different nano/microstructures, and diverse applications are summarized and discussed. For the sections of its applications in surface modification and biomedicine, we mainly highlight the achievements in the past few years (2016-2019). The remaining challenges and future perspectives of PDA-based nanoplatforms are discussed rationally at the end. This timely and overall review should be desirable for a wide range of scientists and facilitate further development of surface coating methods and the production of PDA-based materials.

Nanobiomaterials: from 0D to 3D for tumor therapy and tissue regeneration

Nanobiomaterials have attracted tremendous attention in the biomedical field. Especially in the past few years, a large number of low dimensional nanobiomaterials, including 0D nanostructures, 1D nanotubes and 2D nanosheets, were employed for tumor therapy due to their optically triggered tumor therapy effects and drug loading capacities. However, these low dimensional nanobiomaterials cannot support cell adhesion and possess poor tissue regeneration ability, thus they are not suitable for application in regenerative medicine. Three dimensional (3D) nanofiber scaffolds have attracted extensive attention in tissue regeneration, including bone, skin, nerve and cardiac tissues, due to their similar extracellular matrix structures. Additionally, many 3D scaffolds displayed bone and cartilage regeneration abilities. Therefore, to obtain materials with both tumor therapy and tissue regeneration abilities, it is meaningful and necessary to develop 3D nanobiomaterials with multifunctions. In this review, we systematically review the research progress of nanobiomaterials with varied dimensional structures including 0D, 1D, 2D and 3D, as well as evolutional functions from single tumor therapy to simultaneous tumor therapy and tissue regeneration. This review may pave the way for developing an interdisciplinary research of nanobiomaterials in combination of tumor therapy and regenerative medicine.

Functionalized theranostic nanocarriers with bio-inspired polydopamine for tumor imaging and chemo-photothermal therapy

Nanocarriers sensitive to near infrared light (NIR) are useful templates for chemo-photothermal therapy (PTT) and imaging of tumors due to the ability to change the absorbed NIR energy to heat. The conventional photo-absorbing reagents lack the efficient loading and release of drug before reaching the target site leading to insufficient therapeutic outcomes. To overcome these limitations, the surface of nanocarriers can be modified with different polymers with wide functionalities to provide systems with diagnostic, therapeutic, and theranostic capabilities. Among various polymers, polydopamine (PDA) has been more interested due to complex structure with various chemical moieties, and the capacity to be used through different coating mechanism. In this review, we describe the complex structure, chemical properties, and coating mechanisms of PDA. Moreover, the advantage and surface modification of some relevant nanosystems based on carbon materials, gold, iron oxide, manganese, and upconverting nanomaterials by using PDA will be discussed, in detail.

Construction of a Polypyrrole-Based Multifunctional Nanocomposite for Dual-Modal Imaging and Enhanced Synergistic Phototherapy against Cancer Cells

Design and construction of multifunctional theranostic nanoplatforms are still desired for cancer-effective treatment. Herein, a kind of polypyrrole (PPy)-based multifunctional nanocomposite was designed and successfully constructed for dual-model imaging and enhanced synergistic phototherapy against cancer cells. Through graphene oxide (GO) sheet coating, PPy nanoparticles (NPs) were effectively combined with polyethylene glycol chains, Au NPs, and IR820 molecules. The obtained PGPAI NPs showed promising ability for photoacoustic/computed tomography imaging. Under near-infrared light irradiation, the PPy core and IR820 molecule effectively generated heat and reactive oxygen species (ROS), respectively. Furthermore, the loaded Au NPs owning catalase-like activity produced oxygen by decomposing H₂O₂ (up-regulated in tumor region), enhancing the oxygen-dependent photodynamic therapy efficacy. The formed PGPAI NPs were also proved to own desirable photothermal conversion efficiency, photothermal stability, colloidal stability, cytocompatibility, and cellular internalization behaviors. Furthermore, cell assay demonstrated that PGPAI NPs displayed enhanced synergistic phototherapy efficacy against cancer cells. These developed multifunctional nanoplatforms are promising for effective cancer theranostic applications.

Polydopamine-coated magnetic mesoporous silica nanoparticles for multimodal cancer theranostics

Polydopamine-coated mesoporous silica nanoparticles loaded with ultrasmall Fe₃O₄ nanoparticles can be prepared for multimodal imaging and combination therapy of tumors.

Precise control of apoptosis via gold nanostars for dose dependent photothermal therapy of melanoma

Precise induction and monitoring of cell apoptosis are significant for cancer treatment.

Dendrimer-Stabilized Gold Nanoflowers Embedded with Ultrasmall Iron Oxide Nanoparticles for Multimode Imaging-Guided Combination Therapy of Tumors

Development of multifunctional theranostic nanoplatforms with improved diagnostic sensitivity and therapeutic efficiency of tumors still remains a great challenge. A unique multifunctional theranostic nanoplatform based on generation 5 (G5) poly(amidoamine) dendrimer-stabilized gold nanoflowers (NFs) embedded with ultrasmall iron oxide (USIO) nanoparticles (NPs) for multimode T 1-weighted magnetic resonance (MR)/computed tomography (CT)/photoacoustic (PA) imaging-guided combination photothermal therapy (PTT) and radiotherapy (RT) of tumors is reported here. G5 dendrimer-stabilized Au NPs and citric acid-stabilized USIO NPs are separately prepared, the two particles under a certain Fe/Au molar ratio are mixed to form complexes, the complexes are exposed to Au growth solution to form NFs via a seed-mediated manner, and the remaining dendrimer terminal amines are acetylated. The formed dendrimer-stabilized Fe3O4/Au NFs (for short, Fe3O4/Au DSNFs) have a mean diameter of 99.8 nm, display good colloidal stability and cytocompatibility, and exhibit a near-infrared absorption feature. The unique structure and composition of the Fe3O4/Au DSNFs endows them with a high r 1 relaxivity (3.22 mM-1 s-1) and photothermal conversion efficiency (82.7%), affording their uses as a theranostic nanoplatform for multimode MR/CT/PA imaging and combination PTT/RT of tumors with improved therapeutic efficacy, which is important for translational nanomedicine applications.

Synthesis and SERS activity of super-multibranched AuAg nanostructure via silver coating-induced aggregation of nanostars

The super-multibranched AuAg bimetallic nanostructures are synthesized due to the aggregation of Au nanostars in the process of silver coating. The super-multibranched bimetallic nanostructures with different silver coating thickness are obtained by changing the concentration of silver nitrate and ascorbic acid. It has been found that the formation of these nanostructures is due to the stacking of several nanostars during the process of silver coating. By comparing the silver coating process of gold nanostars with different branch lengths, we found that the nanostars with longish branches are easy to aggregate and form the super-multibranched nanostructures in the process of silver coating. In the AuAg bimetallic nanostructures, the silver layer is mainly covered on the surface of the cores and the thickness increases with the increasing of the AgNO₃, which leads to the change of the surface-enhanced Raman scattering (SERS) activity. It has been found that the SERS activity is stronger when the silver layer is thin and the Au branches are still exposed to the outside of the Ag shell. The sample with the strongest SERS activity has been used to detect thiram with different concentrations. The Raman intensity increases linearly with the logarithmic concentration of thiram ranging from 10^-3 to 10^-7 M with a detection limit of 6.3 × 10^-7 M. These experimental results show that the super-multibranched bimetallic nanostructures have a broad application prospect in molecular detection and biologic sensing based on SERS.

Application of polydopamine in tumor targeted drug delivery system and its drug release behavior

Inspired by the bionics of marine mussels, polydopamine (PDA), a new polymer with unique physicochemical properties was discovered. Due to its simple preparation, good biocompatibility, unique drug-loading methods, PDA has attracted tremendous attentions in field of drug delivery and imaging, and the combination of chemotherapy and other therapies or diagnostic methods, such as photothermotherapy (PTT), photoacoustic imaging (PAI), magnetic resonance imaging (MRI), etc. As an excellent drug carrier in tumor targeted drug delivery system, the drug release behavior of drug-loaded PDA-based nanoparticles is also an important factor to be considered in the establishment of drug delivery systems. Therefore, the purpose of this review is to provide a comprehensive overview of the various applications of PDA in tumor targeted drug delivery systems and to gain insight into the release behavior of the drug-loaded PDA-based nanocarriers. A sufficient understanding and discussion of these aspects is expected to provide a better way to design more rational and effective PDA-based tumor nano-targeted delivery systems. Apart from this, the prospects for the future application of PDA in this field and some unique insights are listed at the end of the article.

Multistimuli-responsive drug vehicles based on gold nanoflowers for chemophotothermal synergistic cancer therapy

AIM

To design and synthesize a novel multistimuli-responsive drug vehicle based on gold nanoflowers (AuNFs) for chemophotothermal synergistic cancer therapy.

MATERIALS & METHODS

Multistimuli-responsive drug-delivery system based on doxorubicin (DOX)/polydopamine (PDA)-functionalized AuNFs (Lan-AuNFs@PDA/DOX) was prepared. The structural characteristics, photothermal properties and stimuli-responsive drug release properties of Lan-AuNFs@PDA/DOX were evaluated. Antitumor studies in vivo and in vitro were performed.

RESULTS

Lan-AuNFs@PDA/DOX exhibited uniform morphology, excellent biocompatibility and photothermal conversion efficiency, which could also respond to stimulus including near infrared light and pH to trigger on demand drug release. The excellent synergistic therapeutic efficacy was confirmed both in vitro and in vivo.

CONCLUSION

Lan-AuNFs@PDA/DOX would be a promising drug carrier, endowing a great potential for multistimuli-responsive chemophotothermal synergistic cancer therapy.

Decorating gold nanostars with multiwalled carbon nanotubes for photothermal therapy

Gold nanoparticles and carbon nanotubes have attracted substantial attention in recent years for their potential applications in photothermal therapy (PTT) as an emerging breakthrough in cancer treatment. Herein, a hybrid nanomaterial of gold nanostars/multiwalled carbon nanotubes (MWCNTs) was synthesized by two-step reduction via the control of several synthetic conditions such as the reducing agent, pH value, concentration and ratio of reagents. The material shows good biocompatibility and high photothermal conversion efficiency, demonstrating its applicability in PTT. The lack of surfactant in the synthesis process made the hybrid nanomaterial cell-friendly, with no effects on viability in vitro. The MWCNT/gold nanostars hybrid nanomaterial presented 12.4% higher photothermal efficiency than gold nanostars alone and showed a 2.4-fold increase over gold nanospheres based on a heating test under 808 nm laser irradiation. Moreover, the MWCNTs/gold nanostars at low concentration (0.32 nM) exhibited remarkably improved photothermal cancer cell-killing efficacy, which may be attributed to the surface plasmon resonance absorption of the gold nanostars and the combined effects of enhanced coupling between the MWCNTs and gold nanostars. Collectively, these results demonstrate that the MWCNTs/gold nanostars developed herein show prominent photothermal value, and thus may serve as a novel photothermal agent for cancer therapy.

Radiotherapy-Sensitized Tumor Photothermal Ablation Using γ-Polyglutamic Acid Nanogels Loaded with Polypyrrole

Development of versatile nanoscale platforms for cancer diagnosis and therapy is of great importance for applications in translational medicine. In this work, we present the use of γ-polyglutamic acid (γ-PGA) nanogels (NGs) to load polypyrrole (PPy) for thermal/photoacoustic (PA) imaging and radiotherapy (RT)-sensitized tumor photothermal therapy (PTT). First, a double emulsion approach was used to prepare the cystamine dihydrochloride (Cys)-cross-linked γ-PGA NGs. Next, the cross-linked NGs served as a reactor to be filled with pyrrole monomers that were subjected to in situ oxidation polymerization in the existence of Fe(III) ions. The formed uniform PPy-loaded NGs having an average diameter of 38.9 ± 8.6 nm exhibited good water-dispersibility and colloid stability. The prominent near-infrared (NIR) absorbance feature due to the loaded PPy endowed the NGs with contrast enhancement in PA imaging. The hybrid NGs possessed excellent photothermal conversion efficiency (64.7%) and stability against laser irradiation, and could be adopted for PA imaging and PTT of cancerous cells and tumor xenografts. Importantly, we also explored the cooperative PTT and X-ray radiation-mediated RT for enhanced tumor therapy. We show that PTT of tumors can be more significantly sensitized by RT using the sequence of laser irradiation followed by X-ray radiation as compared to using the reverse sequence. Our study suggests a promising theranostic platform of hybrid NGs that may be potentially utilized for PA imaging and combination therapy of different types of tumors.

Polydopamine-Based Multifunctional (Nano)materials for Cancer Therapy

Since Lee published a pioneering paper about polydopamine (PDA), application of that polymer in a number of areas has grown enormously in the last 10 years and is still growing. PDA's spectacular success can be attributed to its unique features, i.e., simple preparation protocol, strong adhesive properties, easy and straightforward functionalization, and biocompatibility. Therefore, this polymer has attracted the attention of a vast group of scientists, including those working in the field of nanomedicine. In consequence, polydopamine has been merged with various nanostructures that differ in size and nature, which has resulted in novel types of multifunctional nanomaterials that have recently been extensively exploited in nanomedicine and particularly in cancer therapy. The aim of this article is to offer insight into the latest achievements (up until the end of 2016) in the field of synthesis and application of nanomaterials based on polydopamine and their application in cancer therapy. The conclusions regarding the application of polydopamine-based nanoplatforms in this area and future prospects are given at the end.

Recent developments in dopamine-based materials for cancer diagnosis and therapy

Dopamine-based materials are emerging as novel biomaterials and have attracted considerable interests in the fields of biosensing, bioimaging and cancer therapy due to their unique physicochemical properties, such as versatile adhesion property, high chemical reactivity, excellent biocompatibility and biodegradability, strong photothermal conversion capacity, etc. In this review, we present an overview of recent research progress on dopamine-based materials for diagnosis and therapy of cancer. The review starts with a summary of the physicochemical properties of dopamine-based materials in general. Then detailed description is followed on their applications in the fields of diagnosis and treatment of cancers. The review concludes with an outline of some remaining challenges for dopamine-based materials to be used for clinical applications.