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In recent years, multifunctional hydrogels have received a great deal of attention because they are biocompatible and can mimic the extracellular matrix. Herein, we prepared hydrogels of biocompatible cross-linked networks with photothermal properties. In this study, a chitosan/polyaniline/laponite (COL) hydrogel with photothermal conversion capability was designed. Polyaniline was firstly grafted onto chitosan and its solution was mixed with oxidized dextran, which was then cross-linked into a hydrogel via a Schiff base reaction. Furthermore, an aluminosilicate clay material, laponite (LAP), was incorporated into the hydrogel. The swelling ratio of the COL hydrogel in various solutions was greater than 580%, and it showed good degradation ability (the mass–loss ratio was over 45% after 28 days). This composite hydrogel was demonstrated to have good photothermal conversion properties and biocompatibility at both the cell (cell viability was over 97%) and animal levels. The COL hydrogel showed a photothermal conversion efficiency of 23.7% under the irradiation of a near-infrared laser. Coupled with the osteogenic differentiation-inducing potential of LAP, the COL hydrogel has the potential to kill tumors via hyperthermia or serve as scaffolds for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

Among various kinds of photothermal conversion materials, polypyrrole (PPy) has attracted ever‐increasing attention because of its good biocompatibility and excellent near‐infrared light response property. In this research, the core‐shell nanoparticles with magnetic Fe3O4 as the core and mesoporous silica (MSN) as the shell were prepared, the resulted Fe3O4@MSN nanoparticles were then surface coated with a layer of PPy and further modified with polyvinylpyrrolidone (PVP) to gain colloidal stability. The Fe2+ in Fe3O4 can catalyze the decomposition of H2O2 in tumor cells to produce cytotoxic hydroxyl radicals, thus realizing the tumor chemodynamic therapy. Meanwhile, the MSN layer gives the nanoparticles a higher drug loading capacity of chemotherapeutics (doxorubicin, DOX). Therefore, the prepared Fe3O4@MSN@PPy‐PVP nanoparticles not only have good biocompatibility, magnetism and colloidal stability but also can realize the combined tumor photothermal, chemo, and chemodynamic therapy. This study demonstrates the rational design of multifunctional nanoplatforms for biomedical applications. [ABSTRACT FROM AUTHOR]

Multifunctional nanomaterials for cancer therapy has attracted researchers' attention for decades. In this study, a unique oxidative method using KMnO4 or K2MnO4 as oxidizing agents to oxidize dopamine (DA) to polydopamine (PDA) was reported. The oxidizing agent was reduced to MnOx to form MnOx/PDA composite NPs. Afterwards, the MnOx/PDA composite NPs were surface‐modified with bovine serum albumin (BSA) to form a multifunctional theranostic agent, named MnOx/PDA@BSA NPs, with improved colloidal stability and biocompatibility. Such a material would become a photothermal nanoagent, since the PDA renders the composite NPs an admirable photothermal transforming ability with the photothermal conversion efficiency of 27.06%. Meanwhile, as a commonly used T1 contrast agent, manganese (Mn2+) endowed the MnOx/PDA@BSA NPs with MRI ability, rendering the as‐synthesized MnOx/PDA composite NPs a capability of imaging guided multi‐modal tumor therapy. Moreover, the formed MnOx/PDA@BSA NPs were used for drug loading, which was found to own the tunable drug loading and controlled drug releasing capacity. The as‐prepared composite NPs were successfully used for the combined tumor chemotherapy and photothermal therapy in vitro and in vivo. This research provides insights into the development of conjugated polymer‐based nanomaterial for various biomedical applications, especially in imaging guided cancer therapy. [ABSTRACT FROM AUTHOR]

The integration of efficient imaging for diagnosis and synergistic tumor therapy into a single-component nanoplatform is much promising for high efficacy tumor treatment but still in a great challenge. Herein, a smart and versatile nanotheranostic platform based on hollow mesoporous Prussian blue nanoparticles (HMPBs) with perfluoropentane (PFP) and doxorubicin (DOX) inside, has been designed, for the first time, to achieve the distinct in vivo synergistic chemo-thermal tumor therapy and synchronous diagnosis and monitoring by ultrasound (US)/photoacoustic (PA) dual mode imaging. The prepared HMPBs show excellent photothermal conversion properties with large molar extinction coefficient (≈1.2 × 1011 m−1 cm−1) and extremely high photothermal conversion efficiency (41.4%). Such a novel theranostic nanoplatform is expected to overcome the inevitable tumor recurrence and metastasis resulting from the inhomogeneous ablation of single thermal therapy, which will find a promising prospect in the application of noninvasive cancer therapy. [ABSTRACT FROM AUTHOR]

High recurrence rates after surgery and unacceptable side effects of chemotherapy and radiotherapy are challenges in the treatment of osteosarcoma (OS). Therefore, the development of nanoplatforms with combined tumor inhibition efficiency and fewer side effects is a promising strategy for the treatment of OS. In this paper, a biocompatible therapeutic nanoplatform (Fe-Zr@PDA@GOx) was constructed with a simple and efficient strategy for the treatment of OS. First, as an excellent Fenton reaction reagent, iron ions in the nanoplatform can generate highly toxic hydroxyl radicals (•OH) with hydrogen peroxide (H 2 O 2) in the tumor microenvironment and induce tumor cell death. Then, the modification of polydopamine endows the nanoplatform with photothermal responsiveness, with a photothermal conversion efficiency of 28.0%. Importantly, the conversed heat by polydopamine both promotes the release of glucose oxidase (GOx) and increases the rate of the Fenton reaction. Furthermore, GOx-mediated starvation treatment (SDT) can also provide suitable reaction conditions and sufficient H 2 O 2 to realize the amplification of chemodynamic therapy (CDT). Finally, the doping of Zr ions can interact with Fe to form dual active centers in the Fenton reaction and further accelerate the generation of •OH. Both in vitro and in vivo experiments reveal the synergistic photothermal/CDT/SDT anti-tumor effect. Therefore, this work provides an effective strategy for the treatment of OS. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a methacrylic gelatin/oxidized dextran/montmorillonite‑strontium/polypyrrole (GOMP) hydrogel was prepared. The GOMP hydrogel had dual network structure which was formed through photoinitiator-initiated double bond polymerization and Schiff base reaction. The network structure led to a sustained release of the antitumor drug, doxorubicin (DOX). Polypyrrole introduced the conductivity and high photothermal conversion capacity to the GOMP hydrogel, which showed a photothermal conversion efficiency of 31.61 % under 808 nm laser radiation. The GOMP hydrogel had good swelling properties in solvents. Further study showed that the GOMP hydrogel had good biocompatibility and excellent biodegradability in vitro and in vivo. The experiments of in vitro tumor therapy and in vivo anti-tumor recurrence indicated that the DOX-loaded GOMP hydrogel had synergistic effects on tumor cell apoptosis based on chemotherapy and photothermal therapy. In addition, montmorillonite‑strontium (MMT-Sr) doped in the hydrogel not only improved the mechanical properties of the hydrogel but also promoted potential bone regeneration. The multifunctional DOX-loaded GOMP hydrogel with bone regeneration, photothermal therapy, and chemotherapy functions has great potential application for treating osteosarcoma. [ABSTRACT FROM AUTHOR]

Chitosan has been widely used in biomedical fields due to its good antibacterial properties, excellent biocompatibility, and biodegradability. In this study, a pH-responsive and self-healing hydrogel was synthesized from 3-carboxyphenylboronic acid grafted with chitosan (CS-BA) and polyvinyl alcohol (PVA). The dynamic boronic ester bonds and intermolecular hydrogen bonds are responsible for the hydrogel formation. By changing the mass ratio of CS-BA and PVA, the tensile stress and compressive stress of hydrogel can controlled in the range of 0.61 kPa - 0.74 kPa and 295.28 kPa - 1108.1 kPa, respectively. After doping with tannic acid (TA)/iron nanocomplex (TAFe), the hydrogel successful killed tumor cells through the near infrared laser-induced photothermal conversion and the TAFe-triggered reactive oxygen species generation. Moreover, the photothermal conversion of the hydrogel and the antibacterial effect of CS and TA give the hydrogel a good antibacterial effect. The CS-BA/PVA/TAFe hydrogel exhibit good in vivo and in vitro anti-tumor recurrence and antibacterial ability, and therefore has the potential to be used as a powerful tool for the prevention of local tumor recurrence and bacterial infection after surgery. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, superparamagnetic ferric oxide (Fe 3 O 4) nanospheres were prepared by hydrothermal synthesis and Fe 3 O 4 @MSN@PPy-HA composite microspheres were prepared by coating the Fe 3 O 4 with mesoporous silica nanospheres (MSN) layer, photothermal conversion materials polypyrrole (PPy) and tumor-targeting ligand hyaluronic acid (HA). The chemotherapy drug doxorubicin (DOX) was added to the above materials to prepare the tumor-targeting Fe 3 O 4 @MSN@PPy-HA@DOX microspheres. The composite nanospheres have excellent drug loading ability, controlled drug release ability, photothermal conversion performance, and good biological safety, which can be used in the treatment of tumors. Under the irradiation of the NIR laser, the photothermal conversion efficiency of Fe 3 O 4 @MSN@PPy-HA nanospheres can reach 24.61 %, realizing the thermal ablation of tumor sites. The bivalent iron ion (Fe2+) contained in the nanospheres can have a Fenton reaction with the hydrogen peroxide (H 2 O 2) in tumor cells to form cytotoxic hydroxyl radical (·OH), thus achieving the tumor chemodynamic therapy (CDT). This study confirmed that the microspheres have a good tumor inhibition effect and provided a new idea for the design of multifunctional composite nanomaterials. [Display omitted] [ABSTRACT FROM AUTHOR]

• One-pot synthesis of surface polyvinyl pyrrolidone modified polypyrrole. • The relationship between polypyrrole structure and physicochemical property. • Polypyrrole exhibits combined tumor photothermal-chemotherapy ability. With an excellent near-infrared (NIR) light-responsive property, polypyrrole (PPy) nanoparticle has emerged as a promising NIR photothermal transducing agent for tumor photothermal therapy (PTT). Herein, we reported the PVP mediated one-pot synthesis of colloidal stable and biocompatible PPy nanoparticles (PPy-PVP NPs) for combined tumor photothermal-chemotherapy. The influence of molecular weight and PVP concentration on the spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency of the resultant PPy-PVP NPs was systematically studied. By choosing PVP with a molecular weight of 360 kDa (concentration of 5 mg/mL) as the template and surface modifier during the synthesis, PPy-PVP NPs with optimal spectroscopic characteristic, photothermal feature, drug loading performance, and antitumor efficiency were synthesized. Findings in this study are anticipated to provide an in-depth understanding of the important character of surface engineering in the rational design and biomedical applications of PPy NPs. [ABSTRACT FROM AUTHOR]

The conventional method of using montmorillonite hemostatic materials affects the hemostatic effect due to easy dislodgement on the wound surface. In this paper, a multifunctional bio-hemostatic hydrogel (CODM) was prepared based on hydrogen bonding and Schiff base bonding using modified alginate, polyvinylpyrrolidone (PVP), and carboxymethyl chitosan. The amino group-modified montmorillonite was uniformly dispersed in the hydrogel by its amido bond formation with the carboxyl groups of carboxymethyl chitosan and oxidized alginate. The catechol group, –CHO, and PVP can form hydrogen bonds with the tissue surface to afford the firm tissue adhesion to afford the wound hemostatic. The addition of montmorillonite-NH 2 further improves the hemostatic ability, making it better than commercial hemostatic materials. Moreover, the photothermal conversion ability (derived from the polydopamine) was synergized with the phenolic hydroxyl group, quinone group, and the protonated amino group to effectively kill the bacteria in vitro and in vivo. Based on its in vitro and in vivo biosafety and satisfactory degradation ratio anti-inflammatory, antibacterial, and hemostatic properties, the CODM hydrogel holds promising potential for emergency hemostasis and intelligent wound management. [ABSTRACT FROM AUTHOR]

In this study, a composite hydrogel (QMPD hydrogel) composed of methacrylate anhydride (MA) grafted quaternary ammonium chitosan (QCS-MA), polyvinylpyrrolidone (PVP), and dopamine (DA) was designed for the sequential wound inflammation elimination, infection inhibition, and wound healing. The QMPD hydrogel formation was initiated by the ultraviolet light-triggered polymerization of QCS-MA. Furthermore, hydrogen bonds, electrostatic interactions, and "π-π" stacking between QCS-MA, PVP, and DA were involved in the hydrogel formation. In this hydrogel, the quaternary ammonium groups of quaternary ammonium chitosan and the photothermal conversion of polydopamine are capable of killing bacteria on wounds, which showed the bacteriostatic ratios of 85.6 % and 92.5 % toward Escherichia coli and Staphylococcus aureus , respectively. Moreover, the oxidation of DA sufficiently scavenged free radicals and introduced the QMPD hydrogel with good anti-oxidant and anti-inflammatory abilities. Together with the extracellular matrix-mimic tropical structure, the QMPD hydrogel significantly promoted the wound management of mice. Therefore, the QMPD hydrogel is expected to provide a new method for the design of wound healing dressings. [ABSTRACT FROM AUTHOR]

The degradation of extracellular matrix (ECM) to increase drug permeability is an attractive approach to enhancing pancreatic cancer therapy efficiency. Herein, polypyrrole nanoparticles (PPy NPs) were prepared by a template-guided chemical oxidation method. These PPy NPs with abundant surface pores were used to load the anticancer drug doxorubicin (DOX). In order to intelligently control the DOX release, PPy/DOX NPs were further entrapped with a thermoresponsive ligand, lauric acid (LA), to form PPy-LA/DOX NPs. Bromelain (BL) was then grafted onto the surface of PPy-LA NPs or PPy-LA/DOX NPs through an amidation reaction with the carboxyl group of LA. It was found that the DOX release of PPy-LA/DOX NPs was pH and temperature responsive, reaching a maximum amount of 85.9% within 48 h at pH = 5.4 and 50 °C. Moreover, it was demonstrated that the resultant PLB (PPy-LA-BL) NPs could efficiently hydrolyze the collagen in ECM and enhance the permeability of DOX to the pancreatic tumor. Remarkably, PLB NPs not only featured admirable photothermal conversion but also exhibited obvious photoacoustic imaging capability, which enabled imaging-guided enhanced tumor ablation. This study is anticipated to provide a feasible strategy to improve the permeability of nanoparticles to tumors. [Display omitted] • Polypyrrole/lauric acid/bromelain/doxorubicin (PLBD NPs) were prepared. • LA acts as a temperature responsive doorkeeper to control the DOX release. • BL hydrolyzes collagen of ECM to enhance the penetration of PLBD and DOX in tumors. • PLBD NPs showed the capability of photoacoustic imaging in tumor. [ABSTRACT FROM AUTHOR]

[Display omitted] • MnO 2 /IrO 2 was one-step synthesized and possesses the excellent viability. • The MnO 2 affords the MR imaging and triggers the decomposition of H 2 O 2. • The in-situ formed O 2 promotes the production of cancer cell-toxic 1O 2. • The in-situ formed 1O 2 enhances the tumor photodynamic therapy efficiency. In this research, MnO 2 /IrO 2 nanoplatform was one-step synthesized from the heat-induced oxidation-reduction between potassium permanganate and iridium chloride and modified with polyvinylpyrrolidone (PVP) on the surface to obtain MnO 2 /IrO 2 -PVP nanoparticles (MIP NPs) with excellent colloidal stability of biocompatibility. Then, the photosensitizer Chlorin e6 (Ce6) was loaded onto the surface of MIP NPs. The IrO 2 can efficiently transform the 808 nm near-infrared laser into heat with a photothermal conversion of 27.57 % for tumor photothermal therapy. Interestingly, the MnO 2 can not only react with the redundant H+ and realize the magnetic resonance imaging of the tumor but also catalytic the decomposition of H 2 O 2 in the tumor to generate O 2 and relieve the hypoxia status of the tumor. The in-situ formed O 2 can promote the production of cancer cell-toxic singlet oxygens (1O 2) under the irradiation of 660 nm laser and boost the tumor photodynamic therapy efficiency. Moreover, it was found that PVP can fall off from the MIP NPs to increase their accumulation in the tumor. Such a MIP/Ce6-based nanoplatform which plays the synergism with tumor microenvironment shows promising potential for the combined photo-therapy of the tumor. [ABSTRACT FROM AUTHOR]

• The synthesis of PPy nanoparticles (PPy-PVP NPs) using a vapor deposition method. • This method allows the formation of uniform PPy-PVP NPs at room temperature. • PVP 40kDa can ensure a better performance of the synthesized PPy-PVP NPs. In recent years, nanomaterials have aroused people's interest in the field of biomedicine. Polypyrrole (PPy) has become a research hotspot because of its simple synthesis, excellent photothermal conversion performance, and high biocompatibility. Here, we report the synthesis of PPy nanoparticles (PPy-PVP NPs) using a vapor deposition method, for tumor photothermal therapy. In this method, the slowly produced volatile pyrrole vapor was absorbed by the PVP (polyvinylpyrrolidone)/FeCl 3 aqueous solution. This slow vapor production and absorption allows the formation of uniform PPy-PVP NPs at room temperature. Then, the effects of the molecular weight of PVP on the photothermal property and anti-tumor efficiency of PPy-PVP NPs were compared. It was found that the selection of PVP 40kDa as the template and surface linker can ensure a better application performance of the synthesized nanomaterials. This work provides a theoretical basis for the rational design of nano-therapy carriers and biomedical applications. [ABSTRACT FROM AUTHOR]

• A simple method to synthesize MoS 2 and GOx-containing sodium alginate hydrogel. • The hydrogel consumes the glucose to lead to tumor starvation therapy. • The MAF hydrogel has a good photothermal conversion. • The generated Fe2+ induces a Fenton reaction for chemodynamic therapy of tumors. Starvation therapy (ST) and chemodynamic therapy (CDT) are emerging tumor therapy methods in recent years. In this study, a simple approach was reported to prepare MoS 2 and glucose oxidase (GOx)-containing sodium alginate (ALG)-Fe3+ (MAF) hydrogel. In the hydrogel, there exists an enzymatic reaction to consume glucose to form hydrogen peroxide (H 2 O 2), and a redox reaction between Fe3+ and MoS 2 to form Fe2+ and MoO 4 2−. The formed Fe2+ could be oxidized to Fe3+, which reacts with MAF hydrogel again to continuously produce Fe2+. The consumption of glucose resulted in an obvious tumor ST. Moreover, the produced Fe2+ induced a Fenton reaction to enable the persistent conversion of H 2 O 2 to cytotoxic hydroxyl radicals (·OH) for the CDT of tumors. Together with the high photothermal transforming capability of MoS 2 , the hydrogel was used for the combined tumor photothermal therapy (PTT), ST, and CDT. This work provides a window for the safe use of enzymes for achieving high tumor therapeutic efficacy. [ABSTRACT FROM AUTHOR]

• An injectable therapeutic-laden Konjac glucomannan hydrogel was designed. • The hydrogel was consisted of 5-fluorouracil, calcium folinate and dopamine. • Calcium folinate can enhance the tumor chemotherapy efficiency of 5-fluorouracil. • The combined tumor photothermal and chemotherapy was achieved. Featured with three-dimensional network structure, polymer hydrogels have found tremendous applications in biomedical fields. In this study, therapeutic-laden Konjac glucomannan (KGM) hydrogel was prepared by injecting polydopamine (PDA)/5-fluorouracil (5-FU)/calcium folinate (CF)/KGM alkaline solution to the target area, for the synergistic tumor photothermal and chemotherapy. In alkaline solution, dopamine can be synchronously polymerized to form PDA, while KGM can be hydrolyzed and transformed into a thermally irreversible KGM hydrogel. Besides, the alkaline condition can increase the solubility of 5-FU. The hydrogel matrix can control the release of 5-FU and CF. PDA renders the composite hydrogel excellent tumor photothermal therapy ability. Moreover, CF can be used as a synergist to enhance the tumor chemotherapy efficiency of 5-FU. With convenient handling, excellent photothermal conversion ability and high biocompatibility, the multifunctional hydrogel system is anticipated to find a promising translational potential in clinical therapeutic applications. [ABSTRACT FROM AUTHOR]