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Chinese materia medica has a wide range of clinical applications， but it has many active ingredients with different physicochemical properties， and the target organs， action pathways and mechanisms for different ingredients to exert their efficacy are not the same. Therefore， it is difficult to design and develop a co-delivery system loading multiple components of Chinese materia medica to maximize the synergistic therapeutic efficiency. Based on the characteristics of effectiveness and functionality of active ingredients， the strategies for multi-component co-delivery of Chinese materia medica can be categorized into two types：firstly， based on the effectiveness of active ingredients， new carriers such as liposomes， nanoparticles can be constructed to load multi-components of Chinese materia medica. secondly， based on the functionality of some active ingredients of Chinese materia medica， they are employed in the construction of co-delivery system， which can give play to the dual characteristics of their own efficacy and preparation functions. In this paper， we summarized the relevant research progress of the above two types of multi-component co-delivery strategies， and mainly discussed the pharmaceutical functions of the active ingredients in co-delivery systems， in order to find a more suitable multi-component co-delivery strategy， promoting the design and development of new delivery systems of Chinese materia medica.
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Uveitis, a complex ocular disorder with numerous etiologies, can result from infection, autoimmune, and various physicochemical and mechanical injury factors. The treatment of this disease is difficult, and failure to receive timely and effective treatment can often lead to blindness. With the deepening of people's understanding of uveitis and its related mechanisms, various new sustained-release drug delivery systems for uveitis have been studied. However, due to the existence of various anatomical and physiological barriers in the eye, there are multiple obstacles to the sustained release treatment of uveitis. In this paper, the main research results in this field in recent years are reviewed, and the innovations and limitations of various new sustained-release drug delivery systems are discussed in order to provide new ideas for the sustained-release drug delivery treatment of uveitis in the future. These new sustained-release drug delivery systems will help to completely change the traditional treatment mode of uveitis with side effects and poor compliance in the future, bringing longer targeted sustained release and less toxic reactions.
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Oral administration is the most convenient way of drug delivery， but due to the existence of intestinal barrier， the oral bioavailability of drugs is generally low， especially for drugs with low water solubility， poor permeability and macromolecules. For decades， researchers have demonstrated that nano-delivery system is one of the most effective strategies to solve this problem， but nano-delivery systems have shown limited improvement in the oral bioavailability of drugs. Therefore， researchers have proposed to use transporter-mediated nano-delivery systems to promote the oral absorption of drugs. The intestinal tract were highly expressed as a transporter for ingesting various nutrients（such as glucose， oligopeptides and bile acids）， which was an excellent target of oral drug delivery system. Its substrate were modified on the nano-delivery system， and the loaded drugs could cross the intestinal barrier and enter the systemic circulation more efficiently through the targeting effect of transporters. At present， more and more evidences supported the potential of transporters in the field of oral drug delivery system. Therefore， this paper reviewed the research on intestinal transporters-mediated nano-delivery system to promote oral absorption of drugs， including the distribution of intestinal transporters， three strategies of transporter substrate modification， the transport properties of different types of transporters and their effects of mediating the nano-delivery system for promoting the oral absorption of drugs or treating diseases， with the aim of providing an important theoretical reference for the development of intestinal targeted nano-delivery systems.
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Needle-free injection technology (NFIT) refers to the drug delivery systems in which drugs are propelled as high-speed jet streams using any of the pressure source to penetrate the skin to the required depth. NFIT is a promising drug delivery system as it enables the injection of liquids, powders, and depot/projectiles, and has the advantages of preventing needle stick accidents, improving drug bioavailability, eliminating needle-phobia, increasing vaccine immunity, simplifying operations and is convenient for patients to use. NFIT and its research background, the structure and classification of needle-free jet injectors (NFJI), drugs that can be delivered using NFJI and the factors affecting the injection effect are comprehensively reviewed in this paper. The limitations and potential development directions are summarized to provide a theoretical basis for the application and development of NFIT.
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Aim To prepare tripterygium glycoside nanoparticles and probe into their therapeutic effect on collagen-induced arthritis ( CIA) rats. Methods Tripterygium glycosides polyglycoside nanoparticles were prepared by thin film dispersion method and their quality was assessed. The CIA model was established and drug intervention performed. The body weight, toe swelling degree and arthritis index were measured. The pathological changes of the organs, knee and ankle synovium were observed. The serum levels of kidney function and inflammatory cytokine expression were detected in rats. Results The prepared tripterygium wil-fordii polyglycoside nanoparticles were round particles with uniform distribution and stable properties under electron microscope. Compared with the model group, the swelling of the left and right toes of medication group significantly decreased (P < 0. 01), and the ar-thritis index markedly decreased ( P < 0. 01). Among them, the efficacy of the TG-NPs group was better than that of the TG group. Compared with the normal group, the indexes of heart, spleen, kidney and testis all significantly decreased (P <0. 05, P<0.01). TG-NPs group had a significantly reduced pathological ankle-joint injury in knee cartilage and increased apoptotic synovial cells. Compared with the model group, the serum levels of ALT and BUN and CRE in TG-NPs group were significantly lower (P < 0. 05 ), and IL-1β, TNF-α and IL-6 levels decreased significantly (P <0. 05). Conclusions TG-NPs have good therapeutic effect on CIA through induction of synovial cell apoptosis and decrease of the expression of inflammatory cytokines. By intravenous injection of blood circula-tion, slow and controlled release of drugs can be achieved, the first pass effect caused by oral drug can be avoided, the viscera toxicity can be reduced, which provides an experimental basis for the development of new nanoagents for the treatment of rheumatoid arthritis.
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@#Tumor is the main cause of global related death.Although the existing treatment methods have made significant progress,the lack of specificity and low bioavailability are still the challenge in the treatment.Exosomes are lipid bilayer extracellular vesicles that were released in the range of 30—150 nm when a multi vesicular body(MVB) fuses with plasma membrane,which are important mediators of intercellular communication,and can transport cellular components such as proteins,lipids and nucleic acids to neighboring or distant cells,thus changing the role of recipient cells.Exosomes have been used as natural nano-carriers for drug delivery.After being loaded with antitumor drugs,they can be delivered to the focus for targeted treatment of various tumors,and the therapeutic effect is good.In this paper,the advantages of exosomes-based antitumor drug delivery system,drug loading methods and the research progress of exosomes from different cells in cancer treatment are reviewed so as to provide important basis for the targeted treatment of cancer.
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Osimertinib is an irreversible third representative epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) for the treatment of non-small cell lung cancer (NSCLC) with T790M resistance and classical EGFR mutations. However, the therapeutic effectiveness of osimertinib is limited by acquired drug-resistance, poor water solubility and low tumor accumulation rates. Nanodrug delivery systems can increase the solubility and stability of drugs, prolong the blood circulation time of drugs, improve the uptake rate of cells, promote drug accumulation in tumor tissues, and improve drug resistance. Thus, they are effective in overcoming the limitations of traditional targeted drugs. In this study, we reviewed the mechanism of action of the third-generation EGFR-TKI osimertinib, focused on research advances in osimertinib nanodrug delivery systems against NSCLC, and explored the challenges and future development direction in this field.
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Diseases of ocular fundus are the leading causes of severe vision impairment or even blindness in patients worldwide, and the medical treatments are seriously limited by the difficulty of therapeutic drugs entering the fundus due to the various physiological barriers. Nano-drug delivery systems, with their nanoscale size and large surface area, can be loaded with therapeutic drugs of different physicochemical properties and modified with various surface active substances, which can not only improve the solubility and penetration of the drugs, but also protect biologic drugs from degradation and improve the biological safety and bioavailability, as well as deliver therapeutic drugs to specific ocular targets. All of these make the therapeutic potential enormous. Currently, more and more studies have been carried out to take advantage of nanomaterials for the treatment of different fundus diseases, including neurodegenerative diseases, fundus neovascularization, endophthalmitis and fundus tumors. This review analyzes the challenges and barriers faced by different routes of drug administration in the treatment of fundus diseases, the physicochemical properties of common nano-drug delivery systems that have been studied in related fields, and further summarizes the progress, advantages, limitations, and future directions of the application of various nano-drug delivery systems for the treatment of ocular fundus diseases in recent years.
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Calcium-based biomaterials have been intensively studied in the field of drug delivery owing to their excellent biocompatibility and biodegradability. Calcium-based materials can also deliver contrast agents, which can enhance real-time imaging and exert a Ca2+-interfering therapeutic effect. Based on these characteristics, amorphous calcium carbonate (ACC), as a brunch of calcium-based biomaterials, has the potential to become a widely used biomaterial. Highly functional ACC can be either discovered in natural organisms or obtained by chemical synthesis However, the standalone presence of ACC is unstable in vivo. Additives are required to be used as stabilizers or core-shell structures formed by permeable layers or lipids with modified molecules constructed to maintain the stability of ACC until the ACC carrier reaches its destination. ACC has high chemical instability and can produce biocompatible products when exposed to an acidic condition in vivo, such as Ca2+ with an immune-regulating ability and CO2 with an imaging-enhancing ability. Owing to these characteristics, ACC has been studied for self-sacrificing templates of carrier construction, targeted delivery of oncology drugs, immunomodulation, tumor imaging, tissue engineering, and calcium supplementation. Emphasis in this paper has been placed on the origin, structural features, and multiple applications of ACC. Meanwhile, ACC faces many challenges in clinical translation, and long-term basic research is required to overcome these challenges. We hope that this study will contribute to future innovative research on ACC.
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Small interfering RNA (siRNA) has a promising future in the treatment of ocular diseases due to its high efficiency, specificity, and low toxicity in inhibiting the expression of target genes and proteins. However, due to the unique anatomical structure of the eye and various barriers, delivering nucleic acids to the retina remains a significant challenge. In this study, we rationally design PACD, an A-B-C type non-viral vector copolymer composed of a hydrophilic PEG block (A), a siRNA binding block (B) and a pH-responsive block (C). PACDs can self-assemble into nanosized polymeric micelles that compact siRNAs into polyplexes through simple mixing. By evaluating its pH-responsive activity, gene silencing efficiency in retinal cells, intraocular distribution, and anti-angiogenesis therapy in a mouse model of hypoxia-induced angiogenesis, we demonstrate the efficiency and safety of PACD in delivering siRNA in the retina. We are surprised to discover that, the PACD/siRNA polyplexes exhibit remarkable intracellular endosomal escape efficiency, excellent gene silencing, and inhibit retinal angiogenesis. Our study provides design guidance for developing efficient nonviral ocular nucleic acid delivery systems.
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Este estudo avaliou a eficácia in vitro e in vivo de mantas de nanofibras (NF) de policaprolactona (PCL) incorporadas com nistatina (NIS) no tratamento da estomatite protética (EP) em modelos animais. NF foram sintetizadas com diferentes concentrações de NIS, totalizando quatro soluções: PCL puro, PCL/NIS 0,045 g, PCL/NIS 0,090 g e PCL/NIS 0,225 g. A liberação da NIS foi analisada por espectroscopia Ultravioleta-Visível. A capacidade das mantas de inibirem o biofilme de Candida albicans, principal fator etiológico da EP, dividindo-se cinco grupos (N=5) compostos por um grupo com controle de células de C. albicans e com PCL puro, além das três concentrações de NIS. A seguir, foi analisada a viabilidade celular em queratinócitos humanos (HaCat) por meio do teste colorimétrico de resazurina. Cinco grupos foram divididos (N=10): controle celular, PCL puro e as três concentrações de NIS. Em modelos animais de ratos Wistar albinos (N=18), dispositivos palatinos (DP) de resina acrílica foram confeccionados simulando próteses totais e utilizados para a indução da EP. Para isso, DP contaminados com C. albicans foram cimentados na região molar da cavidade bucal dos animais e permaneceram em boca por 48 h. Após esse período, os DP foram removidos e os animais foram divididos em três grupos: (C) controle; (B1) com tratamento por mantas de PCL/NIS 0,045 g e (B2) PCL/NIS 0,225 g, com N=6. Então novos DP, livres de contaminação, foram cimentados na cavidade oral dos animais e permaneceu por mais 48 h. Após esse período, os animais foram eutanasiados, a contagem de UFC/ mL foi realizada e os palatos foram coletados para a análise histológica. A curva padrão de NIS obtida apresentou R2 de 0,99. As três concentrações de NF apresentaram liberação de NIS, com pico no tempo de 6 h e valores de 66,26 µg/ mL para PCL/NIS 0,045 g, de 333,87 µg/ mL para PCL/NIS 0,090 g e 436,51 µg/ mL para PCL/NIS 0,225 g, constantes até o fim do experimento. Os grupos com NIS reduziram em 2,5 log10 de crescimento do biofilme fúngico em relação aos grupos sem tratamento, Controle e PCL, sem diferença estatística significativa. Não foi observada citotoxicidade nas células HaCat, com viabilidade celular de 93,7% para PCL/NIS 0,045 g, 72,6% para PCL/NIS 0,090 g e 72,4% para PCL/NIS 0,225 g. A indução da EP nos três grupos foi possível e, porém, sem redução significativa na contagem de UFC/ mL de C. albicans nos grupos B1 e B2. Na análise histológica do grupo C pôde-se observar infiltração de hifas de Candida na camada queratinizada, presença de células inflamatórias formando micro abscessos e um discreto infiltrado inflamatório no tecido conjuntivo subjacente ao epitélio infectado. Nos grupos B1 e B2 não foram encontradas alterações epiteliais, concluindo-se que as NF demonstraram atividade antifúngica in vitro e foram efetivas na prevenção da penetração de hifas no tecido palatino de animais com DP (AU)
This study evaluated the in vitro and in vivo efficacy of nanofiber (NF) mats of polycaprolactone (PCL) incorporated with nystatin (NIS) in the treatment of denture stomatitis (DS) in animal models. NFs were synthesized with different concentrations of NIS, totaling four solutions: pure PCL, PCL/NIS 0.045 g, PCL/NIS 0.090 g, and PCL/NIS 0.225 g. The release of NIS was analyzed by Ultraviolet-Visible spectroscopy. The ability of the mats to inhibit Candida albicans biofilm, the main etiological factor of DS, was assessed by dividing five groups (N=5) composed of a group with C. albicans cell control and with pure PCL, in addition to the three concentrations of NIS. Next, cell viability in human keratinocytes (HaCat) was analyzed using the resazurin colorimetric test. Five groups were divided (N=10): cell control, pure PCL, and the three concentrations of NIS. In albino Wistar rat animal models (N=18), palatal devices (PD) made of acrylic resin were fabricated to simulate total prostheses and used to induce DS. For this, PD contaminated with C. albicans were cemented in the molar region of the animals' oral cavity and remained in the mouth for 48 hours. After this period, the PDs were removed, and the animals were divided into three groups: (C) control; (B1) treated with PCL/NIS 0.045 g mats, and (B2) PCL/NIS 0.225 g, with N=6. Then new, uncontaminated PDs were cemented in the animals' oral cavity and remained for another 48 hours. After this period, the animals were euthanized, UFC/ mL counts were performed, and the palates were collected for histological analysis. The standard NIS curve obtained showed an R2 of 0.99. The three concentrations of NF showed NIS release, with a peak at 6 h and values of 66.26 µg/ mL for PCL/NIS 0.045 g, 333.87 µg/ mL for PCL/NIS 0.090 g, and 436.51 µg/ mL for PCL/NIS 0.225 g, remaining constant until the end of the experiment. The groups with NIS reduced fungal biofilm growth by 2.5 log10 compared to the untreated groups, Control and PCL, with no significant statistical difference. No cytotoxicity was observed in HaCat cells, with cell viability of 93.7% for PCL/NIS 0.045 g, 72.6% for PCL/NIS 0.090 g, and 72.4% for PCL/NIS 0.225 g. Induction of DS in the three groups was possible; however, there was no significant reduction in UFC/ mL counts of C. albicans in groups B1 and B2. Histological analysis of group C revealed infiltration of Candida hyphae in the keratinized layer, presence of inflammatory cells forming micro abscesses, and a discreet inflammatory infiltrate in the connective tissue underlying the infected epithelium. No epithelial alterations were found in groups B1 and B2, concluding that NFs demonstrated in vitro antifungal activity and were effective in preventing hyphal penetration into palatal tissue in animals with PD.(AU)
Subject(s)
Stomatitis, Denture , Candida albicans , NystatinABSTRACT
ABSTRACT Hydrogels are gaining widespread popularity in the biomedical field due to their extraordinary properties, such as biocompatibility, biodegradability, zero toxicity, easy processing, and similarity to physiological tissue. They have applications in controlled drug release, wound dressing, tissue engineering, and regenerative medicine. Among these applications, hydrogels as a controlled drug delivery system stands out, which releases active substances in precise amounts and at specific times. To explore the latest advances in the design of hydrogels, a literature review of articles published in indexed scientific journals, in Scopus and Science Direct, was carried out. This review aimed to discover and describe the most innovative hydrogel research with applications in the biomedical field; hydrogels synthesized with polymers of different origins were selected, such as; i. Natural (dextran, agarose, chitosan, etc.); ii. Synthetic (polyacrylamide, polyethylene glycol, polyvinyl alcohol, etc.); iii. Composites (interpenetrants, hybrid crosslinkers, nanocomposites, etc.). Comparative analysis revealed that hydrogels with composite materials show the most promise. These composite hydrogels combine the advantages of different polymers or incorporate additional components, offering enhanced properties and functionalities. In summary, hydrogels are versatile biomaterials with immense potential in biomedicine. Their unique properties make them suitable for diverse applications. However, innovative designs and formulations must continue to be explored to further advance the capabilities of hydrogels and expand their biomedical applications.
RESUMEN Los hidrogeles están ganando una extensa popularidad en el campo biomédico gracias a que presentan propiedades extraordinarias como biocompatibilidad, biodegradabilidad, nula toxicidad, fácil procesamiento, y similitud con el tejido fisiológico. tienen aplicaciones en la liberación controlada de fármacos, el vendaje de heridas, la ingeniería de tejidos y la medicina regenerativa. Entre estas aplicaciones, destaca el uso de hidrogeles como sistema de administración controlada de fármacos, que liberan sustancias activas en cantidades precisas y en momentos concretos. Para explorar los últimos avances en el diseño de hidrogeles, se realizó una revisión bibliográfica de artículos publicados en revistas científicas indexadas, en Scopus y Science Direct. El objetivo de esta revisión fue descubrir y describir las investigaciones de hidrogeles más innovadoras con aplicaciones en el campo biomédico, se seleccionaron hidrogeles sintetizados con polímeros de diferente índole como; i. Naturales (dextrano, agarosa, quitosano, etc.); ii. Sintéticos (poliacrilamida, polietilenglicol, alcohol polivinílico, etc); iii. Compuestos (interpenetrantes, reticulantes híbridos, nanocompuestos, etc.). El análisis comparativo reveló que los hidrogeles que utilizan materiales compuestos son los más prometedores. Estos hidrogeles compuestos combinan las ventajas de distintos polímeros o incorporan componentes adicionales, ofreciendo propiedades y funcionalidades mejoradas. En resumen, los hidrogeles son biomateriales versátiles con un inmenso potencial en biomedicina. Sus propiedades únicas los hacen adecuados para diversas aplicaciones, sin embargo, se debe seguir explorando diseños y formulaciones innovadores para seguir avanzando en las capacidades de los hidrogeles y ampliar sus aplicaciones biomédicas.
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With the advancement in the study of keratoconjunctivitis sicca and the scope of its treatment, punctal plugs are being widely used for the therapeutic management of dry eye disease. With the emergence of 3D printing in medicine, 3D printing of punctal plugs that have an inbuilt drug delivery system and also that can be personalized from patient to patient according to their punctum size can be a great therapeutic option. Another benefit of the device is that its printing takes a short period of time and is cost-effective. This study aimed at making an open source design and 3D printing an efficient model of a punctal plug with an inbuilt drug delivery system that can be eventually used for the treatment of various ocular diseases that require frequent drug instillation or blockage of the nasolacrimal pathway. The 3D design for the punctal plug was made using the open source application, FreeCAD, and slicing was done using the application ChituBox. After that, the plugs were printed using the LCD printer Crealty LD-002R. The material used was resin that was compatible with the Crealty LD-002R. Punctal plugs with satisfactory results were printed using the LCD printer. The punctal plugs showed suitable structure and were also easily reproduced in the 3D printer without any complications or setbacks.
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Neovascularization is the hallmark of many fundus diseases, including diabetic retinopathy, retinal vein occlusion and neovascular age-related macular degeneration.More and more evidence suggests that vascular endothelial growth factor (VEGF) plays a critical role in neovascularization.Anti-VEGF drugs are the first-line treatment for neovascular fundus diseases and have achieved significant results.However, there are drawbacks such as short drug half-lives and the need for long-term administration to maintain effective concentrations, which increases the economic burden and medical risk for patients and reduces compliance.Therefore, finding a new method for intraocular drug delivery is of great clinical importance.Based on the principle that diabetes patients use insulin pumps to gradually release drugs, the ocular anti-VEGF drug delivery system can continuously release anti-VEGF drugs over a period of time, significantly reducing the injection frequency and improving patient compliance.At present, the research on ocular anti-VEGF drug delivery systems is still immature, and various systems are in different stages of clinical trials.According to different design principles, they can be divided into three categories with their characteristics, micropump (extraocular storage delivery systems), biodegradable implants, and non-biodegradable implants.This article summarized and analyzed the controlled ocular anti-VEGF drug release delivery systems currently in clinical trials.
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Platelets play an important role in physiological and pathological activities such as thrombosis, inflammation and tumorigenesis. At present, the application of platelets in drug delivery systems is increasingly studied. Compared with traditional drug delivery systems, new drug delivery systems based on platelets and their derivatives can effectively improve the circulation time and selective accumulation, and reduce the occurrence of related immune reactions or off-target toxic and side effects. In this paper, the types and applications of platelet and its derivatives drug delivery systems were summarized in order to provide reference for platelet-related drug delivery research.
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@#Biomimetic nano formulations of biofilms have low immunogenicity, high targeting, and good biocompatibility, and can avoid being cleared by the endothelial reticular system, thus with in longer blood circulation time in the body.This article mainly reviews the main types as well as advantages and disadvantages of biomimetic nano formulations of biofilms, including tumor cell membranes, red blood cell membranes, platelet membranes, white blood cell membranes, stem cell membranes, extracellular vesicles (exosomes, microvesicles, and apoptotic bodies), endoplasmic reticulum membranes, and composite biofilms, with also a prospect of the challenges facing biomimetic nano formulations of biofilms and their future development based on their current research status, aiming to provide some insight for further research on biomimetic nano formulations of biofilms.
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Brain delivery of drugs remains challenging due to the presence of the blood-brain barrier (BBB). With advances in nanotechnology and biotechnology, new possibilities for brain-targeted drug delivery have emerged. Biomimetic nano drug delivery systems with high brain-targeting and BBB-penetrating capabilities, along with good biocompatibility and safety, can enable 'invisible' drug delivery. In this review, five different types of biomimetic strategies are presented and their research progress in central nervous system disorders is reviewed. Finally, the challenges and future prospects for biomimetic nano drug delivery systems in intracerebral drug delivery are summarized.
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Photodynamic therapy (PDT) is a new modality for cancer therapy, which has been used in the clinical treatment for various tumors, such as skin cancer, bladder cancer and prostate cancer. Most photosensitizers have the disadvantages of hydrophobic, low bioavailability and the limited tumor targeting ability. The nanoscale delivery systems can improve the solubility of photosensitizers and enhance their accumulation at the tumor sites. The multifunctional nano-delivery systems are prepared in combination with other anti-tumor drugs to enhance the anti-tumor effect. In addition to addressing the issues of poor solubility and the insufficient tumor targeting ability, the nanoscale delivery systems need to improve the pharmacokinetic properties of photosensitizers, facilitating their rapid accumulation at the tumor sites and quick elimination in vivo, and reducing the skin phototoxicity. This review summarizes the recent clinical application of PDT of cancer, the development of photosensitizers, the delivery systems for photosensitizers and the combinatorial application with other therapeutic methods. The goal is to present an understanding of knowledge on the design of new types of photosensitizers and its clinical application in PDT of cancer.
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Intracerebral delivery of drugs for the treatment of central nervous system disorders is usually limited by the blood-brain barrier (BBB). Transdermal drug delivery systems (TDDS) have the advantage of improving patient compliance and avoiding first-pass effects compared to intravenous, oral and intranasal drug delivery, and are an emerging non-invasive drug delivery route that facilitates long-term drug delivery to patients. The discovery of direct subcutaneous targeting of lymphatic pathways to brain tissue has made TDDS a new brain-targeted drug delivery strategy. At the same time, the development of nano-delivery technology has further facilitated the application of TDDS for targeted drug delivery to the brain. This review summarizes the mechanism of transdermal drug delivery into the brain and the application of TDDS in the treatment of brain diseases, providing new ideas and methods for the treatment of central nervous system diseases.
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Cancer is still one of the major diseases threatening human life and health. At present, how to achieve precise diagnosis and treatment of tumors is the biggest challenge in cancer treatment. Prodrugs use the tumor specificity of targeting molecules to deliver anticancer drugs to tumor sites, which can effectively improve drug bioavailability, therapeutic efficacy and safety, and are currently a hot spot in the research and development of anticancer drugs. The targeting molecules of prodrugs mainly include nucleic acid aptamers, polymers, antibodies, polypeptides, etc. Among them, polypeptides have the advantages of good biocompatibility, controllable degradation performance, high in vivo responsiveness, and simple and easy preparation methods, and are widely used. It is used to construct peptide-drug conjugates (PDC) prodrugs to achieve targeted therapy of tumors. In recent years, with the development of phage peptide library technology and peptide standard solid-phase synthesis technology, more and more targeted peptides have been discovered and effectively synthesized and modified, providing strong support for the development of PDC. This review briefly introduces the types and functions of functional peptides and linkers in PDC, and discusses the application of PDC in chemotherapy, immunotherapy and photodynamic therapy in tumor targeted diagnosis and treatment, and finally summarizes the difficulties faced by PDC drug development.