Colitis is a common intestinal disease characterized by a chronic course, impaired quality of life and poor prognosis. Due to the anatomical specificity of the colon, the development of targeted and efficient drug delivery systems has become a research focus. With the rapid development of nanotechnology, nano drug delivery systems have been widely used in colitis treatment owing to their ease of preparation, controllable quality and excellent targeting capability. In this review, the general situation of colitis was summarized. Based on the classification of drug delivery carriers of different materials, the application progress of organic polymers, inorganic materials, biological and metallic nano drug delivery systems in colitis therapy was introduced. The potential of these four types of nano drug delivery systems was summarized and analyzed.

Carrier-free self-assembled nanodrugs show broad application prospects in cancer treatment. Compared with carrier-based nanodrugs, carrier-free self-assembled nanodrugs have the advantages of strong targeting ability and high safety, which can significantly improve the therapeutic efficacy against cancer. Their preparation process is simple, involving a variety of non-covalent interactions, and they exhibit better biocompatibility and immune effects in vaccine development. Carrier-free self-assembled nanodrugs can be divided into nanodrugs based on prodrugs, free drugs, and amphiphilic drug conjugates. In this review, the preparation methods of these three types of carrier-free self-assembled nanodrugs and their research progress in cancer treatment in recent years were summarized, and their clinical applications and future prospects were discussed.

Pullulan, a natural polysaccharide, has good biocompatibility and biodegradability. Pullulan and its derivatives show broad application prospects in tumor-targeted delivery and therapy. In this review, various nano delivery systems based on pullulan and its derivatives were reviewed. Among them, pullulan-related nanogels, nanoparticles, and nanomicelles can enhance the targeting and penetration of chemotherapeutic drugs while reducing toxicity to normal tissues, pullulan-related gene nano delivery systems can show good performance and improve gene transfection efficiency, and pullulan-related bioresponsive nano delivery systems can further enhance therapeutic efficacy while avoiding multidrug resistance.

Biomineralization is a unique process for generating biominerals and has become a popular area of research in biomedical materials due to its excellent biocompatibility and biodegradability, as well as the simple and economical synthesis process. In this review, the fundamental concepts of biomineralization and the principles of organic matrix-induced nucleation were introduced. According to the biomimetic mineralization technology mediated by matrices such as proteins and their derivatives, nucleic acids, nanozymes, polysaccharides, organisms, polymers and metal-organic frameworks, the application progress of biomineralization technology to drug delivery by protecting active molecules, constructing drug carriers and responding to acidic environments was reviewed. The difficult problems to be solved were also summarized.

Layered double hydroxides (LDHs) nanomaterial is a two-dimensional nanomaterial with a multi-layer structure. Due to their unique structural composition, LDHs can act as a "molecular switch" to achieve controllable release of payload under specific physiological pH conditions while remaining stable during blood circulation. In addition, LDHs are composed of several specific cations and have specific regulatory effects on various cellular functions. In addition to the excellent drug loading performance, LDHs can respond to the tumor microenvironment and realize a smart release of drugs, reduce the side effects of drugs, and enhance the tumor killing effect, having a wide range of applications in the field of tumor therapy. In this paper, the research progress of LDHs for chemotherapy drug delivery, immunotherapy, photodynamic therapy, and immunocombination therapy for tumors was reviewed.

Immunotherapy, which utilizes the body’s own immune system to fight cancer, has become one of the mainstream clinical strategies for cancer treatment, and the number of immunotherapeutic drugs approved for clinical treatment has increased year by year. However, the tumor microenvironment with immunosuppressive ability significantly reduces the effect of immunotherapy, making immunotherapy suffer from low response rate, poor penetration, and other problems, and the clinical efficacy is not ideal. In this review paper, the methods and mechanisms of action of remodeling the immunosuppressive tumor microenvironment (ITME) by reducing immunosuppressive cells and soluble molecules were summarized, and the important role of combined chemotherapy, radiotherapy, and other therapeutic modalities was explored in remodeling the ITME and enhancing the efficacy of immunotherapy.

Microneedles (MNs) serve as a revolutionary paradigm in transdermal drug delivery, heralding a viable resolution to the formidable barriers presented by the cutaneous interface. This review examines MNs as an advanced approach to enhancing dermatological pathology management. It explores the complex dermis structure and highlights the limitations of traditional transdermal methods, emphasizing MNs' advantage in bypassing the stratum corneum to deliver drugs directly to the subdermal matrix. The discourse outlines the diverse typologies of MNs, including solid, coated, hollow, hydrogel, and dissolvable versions. Each type is characterized by its unique applications and benefits. The treatise details the deployment of MNs in the alleviation of cutaneous cancers, the administration of inflammatory dermatoses such as psoriasis and atopic dermatitis, and their utility in wound management. Additionally, the paper contemplates the prospects of MNs within the realm of aesthetic dermatology and the burgeoning market traction of cosmetic MN formulations. The review summarizes the scientific and commercial challenges to the clinical adoption of MN therapeutics, including dosage calibration, pharmacodynamics, biocompatibility, patient compliance, sterilization, mass production, and regulatory oversight. It emphasizes the need for ongoing research, innovation, and regulatory harmonization to overcome these obstacles and fully realize MNs' potential in treating skin diseases and improving patient welfare.

The abuse of antibiotics and other antimicrobial drugs has led to a significant increase in the prevalence of bacterial drug resistance. The advent of nanotechnology offers a promising way to address this challenge. Metal nanomaterials have emerged as a prominent class of antimicrobial agents, offering a number of advantages, including ease of preparation, high stability, potent efficacy against drug-resistant bacteria, and low toxicity. In this review, the antibacterial mechanisms of metal nanomaterials and the current research progress of gold, silver, copper, iron, platinum, palladium, and gallium nanomaterials and their application in the field of antibacterial were summarized with the aim of providing reference for the antibacterial use of metal nanomaterials.

Diseases caused by microbial infections, including bacteria, fungi, and viruses, are increasing every year. Currently, antibiotics are the primary treatment method for bacterial infections. However, over use of antibiotics can easily lead to bacterial resistance. Due to the broad-spectrum antibacterial properties of copper nanomaterials, they exhibit excellent antibacterial activity against both gram-negative bacteria and gram-positive bacteria. In this review, the preparation methods of copper nanomaterials were summarized, the antibacterial and antiviral effects of copper nanomaterials, and their applications in the fields of antibacterial and antiviral were discussed. Finally, the problems of copper nanomaterials in terms of toxicity and stability were summarized, and their future applications in the fields of antibacterial and antiviral were prospected.

Tumor immunotherapy has become the main treatment method for cancer after surgery, radiotherapy and chemotherapy. With the in-depth study of tumor immunology, cell biology and molecular technology, the tumor microenvironment was found to be immunosuppressive, and tumor development and metastasis are closely related to it. Tumor immunotherapy uses the body’s own immune system to kill tumor cells. At present, there are mainly mainstream tumor immunotherapy methods, namely monoclonal antibody therapy, immune checkpoint inhibitor therapy, immunocell therapy, and tumor vaccines. In this paper, the advantages and limitations of these four immunotherapies were mainly discussed, and the current status of their marketing and clinical research was also reviewed.