Microneedle-Mediated Delivery of Lipid-Coated Cisplatin Nanoparticles for Efficient and Safe Cancer Therapy

Diagnostic, Therapeutic, and Theranostic Multifunctional Microneedles

Microneedles (MNs) have maintained their popularity in therapeutic and diagnostic medical applications throughout the past decade. MNs are originally designed to gently puncture the stratum corneum layer of the skin and have lately evolved into intelligent devices with functions including bodily fluid extraction, biosensing, and drug administration. MNs offer limited invasiveness, ease of application, and minimal discomfort. Initially manufactured solely from metals, MNs are now available in polymer-based varieties. MNs can be used to create systems that deliver drugs and chemicals uniformly, collect bodily fluids, and are stimulus-sensitive. Although these advancements are favorable in terms of biocompatibility and production costs, they are insufficient for the therapeutic use of MNs. This is the first comprehensive review that discusses individual MN functions toward the evolution and development of smart and multifunctional MNs for a variety of novel and impactful future applications. The study examines fabrication techniques, application purposes, and experimental details of MN constructs that perform multiple functions concurrently, including sensing, drug-molecule release, sampling, and remote communication capabilities. It is highly likely that in the near future, MN-based smart devices will be a useful and important component of standard medical practice for different applications.

Development and characterization of magnetic hydrogels loaded with greenly synthesized iron-oxide nanoparticles conjugated with cisplatin

A novel approach was devised to address the challenges in delivering cisplatin (CIS) for lung cancer treatment. This involved the development of a non-invasive hydrogel delivery system, aiming to minimize side effects associated with its administration. Using carbopol 971 (CP) and chitosan (CH) at varying ratios, the hydrogels were prepared and loaded with eco-friendly iron oxide nanoparticles (IONPs) conjugated to CIS. The physical properties, yield, drug loading, and cytotoxicity against lung cancer cell lines (A549) were assessed, along with hydrogel rheological properties and in vitro drug diffusion. Hydrogel A1 that composed of 1:1 of CP:CH hydrogel loaded with 100 mg IONPs and 250 µg CIS demonstrated distinctive properties that indicate its suitability for potential delivery. The loaded greenly synthesized IONPs@CIS exhibited a particle size of 23.0 nm, polydispersity index of 0.47, yield of 71.6%, with 88.28% drug loading. They displayed significant cytotoxicity (61.7%) against lung cancer cell lines (A549), surpassing free CIS cytotoxicity (28.1%). Moreover, they demonstrated shear-thinning behaviour, viscoelastic properties, and Fickian drug release profile over 24 h (flux 2.34 µg/cm2/h, and permeability 0.31 cm/h).

A landscape of recent advances in lipid nanoparticles and their translational potential for the treatment of solid tumors

Lipid nanoparticles (LNPs) are biocompatible drug delivery systems that have found numerous applications in medicine. Their versatile nature enables the encapsulation and targeting of various types of medically relevant molecular cargo, including oligonucleotides, proteins, and small molecules for the treatment of diseases, such as cancer. Cancers that form solid tumors are particularly relevant for LNP-based therapeutics due to the enhanced permeation and retention effect that allows nanoparticles to accumulate within the tumor tissue. Additionally, LNPs can be formulated for both locoregional and systemic delivery depending on the tumor type and stage. To date, LNPs have been used extensively in the clinic to reduce systemic toxicity and improve outcomes in cancer patients by encapsulating chemotherapeutic drugs. Next-generation lipid nanoparticles are currently being developed to expand their use in gene therapy and immunotherapy, as well as to enable the co-encapsulation of multiple drugs in a single system. Other developments include the design of targeted LNPs to specific cells and tissues, and triggerable release systems to control cargo delivery at the tumor site. This review paper highlights recent developments in LNP drug delivery formulations and focuses on the treatment of solid tumors, while also discussing some of their current translational limitations and potential opportunities in the field.

Nano-PROTACs: state of the art and perspectives

PROteolysis TArgeting Chimeras (PROTACs), as a recently identified technique in the field of new drug development, provide new concepts for disease treatment and are expected to revolutionize drug discovery. With high specificity and flexibility, PROTACs serve as an innovative research tool to target and degrade disease-relevant proteins that are not currently pharmaceutically vulnerable to eliminating their functions by hijacking the ubiquitin-proteasome system. To date, PROTACs still face the challenges of low solubility, poor permeability, off-target effects, and metabolic instability. The combination of nanotechnology and PROTACs has been explored to enhance the in vivo performance of PROTACs regarding overcoming these challenging hurdles. In this review, we summarize the latest advancements in the building-block design of PROTAC prodrug nanoparticles and provide an overview of existing/potential delivery systems and loading approaches for PROTAC drugs. Furthermore, we discuss the current status and prospects of the split-and-mix approach for PROTAC drug optimization. Additionally, the advantages and translational potentials of carrier-free nano-PROTACs and their combinational therapeutic effects are highlighted. This review aims to foster a deeper understanding of this rapidly evolving field and facilitate the progress of nano-PROTACs that will continue to push the boundaries of achieving selectivity and controlled release of PROTAC drugs.

Tiny titans- unravelling the potential of polysaccharides and proteins based dissolving microneedles in drug delivery and theranostics: A comprehensive review

In recent years, microneedles (MNs) have emerged as a promising alternative to traditional drug delivery systems in transdermal drug delivery. The use of MNs has demonstrated significant potential in improving patient acceptance and convenience while avoiding the invasiveness of traditional injections. Dissolving, solid, hollow, coated, and hydrogel microneedles are among the various types studied for drug delivery. Dissolving microneedles (DMNs), in particular, have gained attention for their safety, painlessness, patient convenience, and high delivery efficiency. This comprehensive review primarily focuses on different types of microneedles, fabrication methods, and materials used in fabrication of DMNs such as hyaluronic acid, chitosan, alginate, gelatin, collagen, silk fibroin, albumin, cellulose and starch, to list a few. The review also provides an exhaustive discussion on the applications of DMNs, including the delivery of vaccines, cosmetic agents, contraceptives, hormone and genes, and other therapeutic applications like for treating cancer, skin diseases, and diabetes, among others, are covered in this review. Additionally, this review highlights some of the DMN systems that are presently undergoing clinical trials. Finally, the review discusses current advances and trends in DMNs, as well as future prospective directions for this ground-breaking technology in drug delivery.

Advances of Smart Stimulus-Responsive Microneedles in Cancer Treatment

Microneedles (MNs) have emerged as a highly promising technology for delivering drugs via the skin. They provide several benefits, including high drug bioavailability, non-invasiveness, painlessness, and high safety. Traditional strategies for intravenous delivery of anti-tumor drugs have risks of systemic toxicity and easy development of drug resistance, while MN technology facilitates precise delivery and on-demand release of drugs in local tissues. In addition, by further combining with stimulus-responsive materials, the construction of smart stimulus-responsive MNs can be achieved, which can respond to specific physical/chemical stimuli from the internal or external environment, thereby further improving the accuracy of tumor treatment and reducing toxicity to surrounding tissues/cells. This review systematically summarizes the classification, materials, and reaction mechanisms of stimulus-responsive MNs, outlines the benefits and challenges of various types of MNs, and details their application and latest progress in cancer treatment. Finally, the development prospects of smart MNs in tumor treatment are also discussed, bringing inspiration for future precision treatment of tumors.

Nanotechnology-Based Strategies in Parasitic Disease Management: From Prevention to Diagnosis and Treatment

Parasitic infections are a major global health issue causing significant mortality and morbidity. Despite substantial advances in the diagnostics and treatment of these diseases, the currently available options fall far short of expectations. From diagnosis and treatment to prevention and control, nanotechnology-based techniques show promise as an alternative approach. Nanoparticles can be designed with specific properties to target parasites and deliver antiparasitic medications and vaccines. Nanoparticles such as liposomes, nanosuspensions, polymer-based nanoparticles, and solid lipid nanoparticles have been shown to overcome limitations such as limited bioavailability, poor cellular permeability, nonspecific distribution, and rapid drug elimination from the body. These nanoparticles also serve as nanobiosensors for the early detection and treatment of these diseases. This review aims to summarize the potential applications of nanoparticles in the prevention, diagnosis, and treatment of parasitic diseases such as leishmaniasis, malaria, and trypanosomiasis. It also discusses the advantages and disadvantages of these applications and their market values and highlights the need for further research in this field.

A tumor microenvironment-responsive microneedle patch for chemodynamic therapy of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors of the head and neck, and this disease has become a threat to public health due to its poor prognosis and high fatality rate. Chemodynamic therapy (CDT) is an emerging oncology treatment based on the Fenton reaction. However, the lack of endogenous hydrogen peroxide (H2O2) in tumor cells and the high concentration of glutathione (GSH) that depletes toxic hydroxyl radicals (·OH) significantly impair the efficacy of CDT. Here, we developed a polyvinyl alcohol (PVA)-based soluble microneedle patch (denoted as Fe3O4 + VC-MN) loaded with Fe3O4 nanoparticles (NPs) and vitamin C (VC) for the effective treatment of OSCC. When Fe3O4 + VC-MNs are inserted into the OSCC tissue, the Fe3O4 NPs and VC loaded in the tip of the needle are released in a targeted manner. After VC is converted into oxidized vitamin C (DHA), it can consume GSH in tumor cells and generate sufficient intracellular H2O2in situ. Moreover, by virtue of their peroxidase-like activity, Fe3O4 NPs can induce the generation of lethal ·OH through the Fenton reaction with the aforementioned H2O2, leading to tumor cell ferroptosis and apoptosis, thus achieving CDT. Collectively, this functional microneedle patch provides a more efficient and minimally invasive targeted drug delivery solution for the treatment of OSCC.

Smart Responsive Microneedles for Controlled Drug Delivery

As an emerging technology, microneedles offer advantages such as painless administration, good biocompatibility, and ease of self-administration, so as to effectively treat various diseases, such as diabetes, wound repair, tumor treatment and so on. How to regulate the release behavior of loaded drugs in polymer microneedles is the core element of transdermal drug delivery. As an emerging on-demand drug-delivery technology, intelligent responsive microneedles can achieve local accurate release of drugs according to external stimuli or internal physiological environment changes. This review focuses on the research efforts in smart responsive polymer microneedles at home and abroad in recent years. It summarizes the response mechanisms based on various stimuli and their respective application scenarios. Utilizing innovative, responsive microneedle systems offers a convenient and precise targeted drug delivery method, holding significant research implications in transdermal drug administration. Safety and efficacy will remain the key areas of continuous efforts for research scholars in the future.

The Progress in the Application of Dissolving Microneedles in Biomedicine

In recent years, microneedle technology has been widely used for the transdermal delivery of substances, showing improvements in drug delivery effects with the advantages of minimally invasive, painless, and convenient operation. With the development of nano- and electrochemical technology, different types of microneedles are increasingly being used in other biomedical fields. Recent research progress shows that dissolving microneedles have achieved remarkable results in the fields of dermatological treatment, disease diagnosis and monitoring, and vaccine delivery, and they have a wide range of application prospects in various biomedical fields, showing their great potential as a form of clinical treatment. This review mainly focuses on dissolving microneedles, summarizing the latest research progress in various biomedical fields, providing inspiration for the subsequent intelligent and commercial development of dissolving microneedles, and providing better solutions for clinical treatment.

Long-acting microneedle formulations

The minimally-invasive and painless nature of microneedle (MN) application has enabled the technology to obviate many issues with injectable drug delivery. MNs not only administer therapeutics directly into the dermal and ocular space, but they can also control the release profile of the active compound over a desired period. To enable prolonged delivery of payloads, various MN types have been proposed and evaluated, including dissolving MNs, polymeric MNs loaded or coated with nanoparticles, fast-separable MNs hollow MNs, and hydrogel MNs. These intricate yet intelligent delivery platforms provide an attractive approach to decrease side effects and administration frequency, thus offer the potential to increase patient compliance. In this review, MN formulations that are loaded with various therapeutics for long-acting delivery to address the clinical needs of a myriad of diseases are discussed. We also highlight the design aspects, such as polymer selection and MN geometry, in addition to computational and mathematical modeling of MNs that are necessary to help streamline and develop MNs with high translational value and clinical impact. Finally, up-scale manufacturing and regulatory hurdles along with potential avenues that require further research to bring MN technology to the market are carefully considered. It is hoped that this review will provide insight to formulators and clinicians that the judicious selection of materials in tandem with refined design may offer an elegant approach to achieve sustained delivery of payloads through the simple and painless application of a MN patch.

Advance and Challenges in the Treatment of Skin Diseases with the Transdermal Drug Delivery System

Skin diseases are among the most prevalent non-fatal conditions worldwide. The transdermal drug delivery system (TDDS) has emerged as a promising approach for treating skin diseases, owing to its numerous advantages such as high bioavailability, low systemic toxicity, and improved patient compliance. However, the effectiveness of the TDDS is hindered by several factors, including the barrier properties of the stratum corneum, the nature of the drug and carrier, and delivery conditions. In this paper, we provide an overview of the development of the TDDS from first-generation to fourth-generation systems, highlighting the characteristics of each carrier in terms of mechanism composition, penetration method, mechanism of action, and recent preclinical studies. We further investigated the significant challenges encountered in the development of the TDDS and the crucial significance of clinical trials.

Advances in Natural Polymer-Based Transdermal Drug Delivery Systems for Tumor Therapy

As an alternative to traditional oral and intravenous injections with limited efficacy, transdermal drug delivery (TDD) has shown great promise in tumor treatment. Over the past decade, natural polymers have been designed into various nanocarriers due to their excellent biocompatibility, biodegradability, and easy availability, providing more options for TDD. In addition, surface functionalization modification of the rich functional groups of natural polymers, which in turn are developed into targeted and stimulus-responsive functional materials, allows precise delivery of drugs to tumor sites and release of drugs in response to specific stimuli. It not only improves the treatment efficiency of tumor but also reduces the toxic and side effects to normal tissues. Therefore, the development of natural polymer-based TDD (NPTDD) systems has great potential in tumor therapy. In this review, the mechanism of NPTDD systems such as penetration enhancers, nanoparticles, microneedles, hydrogels and nanofibers prepared from hyaluronic acid, chitosan, sodium alginate, cellulose, heparin and protein, and their applications in tumor therapy are overviewed. This review also outlines the future prospects and current challenges of NPTDD systems for local treatment tumors.

Recent Studies and Progress in the Intratumoral Administration of Nano-Sized Drug Delivery Systems

Over the last 30 years, diverse types of nano-sized drug delivery systems (nanoDDSs) have been intensively explored for cancer therapy, exploiting their passive tumor targetability with an enhanced permeability and retention effect. However, their systemic administration has aroused some unavoidable complications, including insufficient tumor-targeting efficiency, side effects due to their undesirable biodistribution, and carrier-associated toxicity. In this review, the recent studies and advancements in intratumoral nanoDDS administration are generally summarized. After identifying the factors to be considered to enhance the therapeutic efficacy of intratumoral nanoDDS administration, the experimental results on the application of intratumoral nanoDDS administration to various types of cancer therapies are discussed. Subsequently, the reports on clinical studies of intratumoral nanoDDS administration are addressed in short. Intratumoral nanoDDS administration is proven with its versatility to enhance the tumor-specific accumulation and retention of therapeutic agents for various therapeutic modalities. Specifically, it can improve the efficacy of therapeutic agents with poor bioavailability by increasing their intratumoral concentration, while minimizing the side effect of highly toxic agents by restricting their delivery to normal tissues. Intratumoral administration of nanoDDS is considered to expand its application area due to its potent ability to improve therapeutic effects and relieve the systemic toxicities of nanoDDSs.

Localized Drug Delivery Systems: An Update on Treatment Options for Head and Neck Squamous Cell Carcinomas

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers in the world, with surgery, radiotherapy, chemotherapy, and immunotherapy being the primary treatment modalities. The treatment for HNSCC has evolved over time, due to which the prognosis has improved drastically. Despite the varied treatment options, major challenges persist. HNSCC chemotherapeutic and immunotherapeutic drugs are usually administered systemically, which could affect the patient's quality of life due to the associated side effects. Moreover, the systemic administration of salivary stimulating agents for the treatment of radiation-induced xerostomia is associated with toxicities. Localized drug delivery systems (LDDS) are gaining importance, as they have the potential to provide non-invasive, patient-friendly alternatives to cancer therapy with reduced dose-limiting toxicities. LDDSs involve directly delivering a drug to the tissue or organ affected by the disease. Some of the common localized routes of administration include the transdermal and transmucosal drug delivery system (DDSs). This review will attempt to explore the different treatment options using LDDSs for the treatment of HNSCC and radiotherapy-induced damage and their potential to provide a better experience for patients, as well as the obstacles that need to be addressed to render them successful.

Microneedle-mediated treatment for superficial tumors by combining multiple strategies

Superficial tumors are still challenging to overcome due to the high risk and toxicity of surgery and conventional chemotherapy. Microneedles (MNs) are widely used in the treatment of superficial skin tumors (SST) due to the high penetration rate of the stratum corneum (SC), excellent biocompatibility, simple preparation process, high patient compliance, and minimal invasion. Most importantly, MNs can provide not only efficient and rarely painful delivery carriers, but also combine multi-model strategies with photothermal therapy (PTT), immunotherapy, and gene therapy for synergistic efficacy. To promote an in-depth understanding of their superiorities, this paper systematically summarized the latest application progress of MNs in the treatment of SST by delivering various types of photosensitizers, immune signal molecules, genes, and chemotherapy drugs. Just as important, the advantages, limitations, and drug release mechanisms of MNs based on different materials are introduced in the paper. In addition, the application of MN technology to clinical practice is the ultimate goal of all the work. The obstacles and possible difficulties in expanding the production of MNs and achieving clinical transformation are briefly discussed in this paper. To be anticipated, our work will provide new insights into the precise and rarely painful treatment of SST in the future.

Fabrication of biodegradable hollow microsphere composites made of polybutylene adipate co-terephthalate/polyvinylpyrrolidone for drug delivery and sustained release

Sustained drug release has attracted increasing interest in targeted drug therapy. However, existing methods of drug therapy suffer drug action time, large fluctuations in the effective concentration of the drug, and the risk of side effects. Here, a biodegradable composite of polybutylene adipate co-terephthalate/polyvinylpyrrolidone (PBAT/PVP) consisting of electrospun hollow microspheres as sustained-released drug carriers is presented. The as-prepared PBAT/PVP composites show faster degradation rate and drug (Erlotinib) release than that of PBAT. Furthermore, PBAT/PVP composites loaded with Erlotinib provide sustained release effect, thus achieving a better efficacy than that after the direct injection of erlotinib due to the fact that the composites allow a high drug concentration in the tumor for a longer period. Hence, this work provides a potential effective solution for clinical drug therapy and tissue engineering using drug microspheres with a sustained release.

Flexible Monitoring, Diagnosis, and Therapy by Microneedles with Versatile Materials and Devices toward Multifunction Scope

Microneedles (MNs) have drawn rising attention owing to their merits of convenience, noninvasiveness, flexible applicability, painless microchannels with boosted metabolism, and precisely tailored multifunction control. MNs can be modified to serve as novel transdermal drug delivery, which conventionally confront with the penetration barrier caused by skin stratum corneum. The micrometer-sized needles create channels through stratum corneum, enabling efficient drug delivery to the dermis for gratifying efficacy. Then, incorporating photosensitizer or photothermal agents into MNs can conduct photodynamic or photothermal therapy, respectively. Besides, health monitoring and medical detection by MN sensors can extract information from skin interstitial fluid and other biochemical/electronic signals. Here, this review discloses a novel monitoring, diagnostic, and therapeutic pattern by MNs, with elaborate discussion about the classified formation of MNs together with various applications and inherent mechanism. Hereby, multifunction development and outlook from biomedical/nanotechnology/photoelectric/devices/informatics to multidisciplinary applications are provided. Programmable intelligent MNs enable logic encoding of diverse monitoring and treatment pathways to extract signals, optimize the therapy efficacy, real-time monitoring, remote control, and drug screening, and take instant treatment.

Microneedle-assisted transdermal delivery of nanoparticles: Recent insights and prospects

Transdermal delivery of drugs offers an interesting alternative for the administration of molecules that present certain troubles when delivered by the oral route. It can produce systemic effects or perform a local action when the formulation exerts an optimal controlled drug release or a targeted delivery to the specific cell type or site. It also avoids several inconveniences of the oral administration such as the hepatic first pass effect, gastric pH-induced hydrolysis, drug malabsorption because of certain diseases or surgeries, and unpleasant organoleptic properties. Nanomedicine and microneedle array patches (MAPs) are two of the trendiest delivery systems applied to transdermal research nowadays. However, the skin is a protective barrier and nanoparticles (NPs) cannot pass through the intact stratum corneum. The association of NPs and MAPs (NPs@MAPs) work synergistically, since MAPs assist NPs to bypass the outer skin layers, and NPs contribute to the system providing controlled drug release and targeted delivery. Vaccination and tailored therapies have been proposed as fields where both NPs and MAPs have great potential due to inherent characteristics. MAPs conception and easy use could allow self-administration and therefore facilitate mass vaccination campaigns in undeveloped areas with weak healthcare services. Additionally, nanomedicine is being explored as a platform to personalize therapies in such an important field as oncology. In this work we show recent insights that prove the benefits of NPs@MAPs association and analyze the prospects and the discrete interest of the industry in NPs@MAPs, evaluating different limiting steps that restricts NPs@MAPs translation to the clinical practice. This article is categorized under: Nanotechnology Approaches to Biology > NA Therapeutic Approaches and Drug Discovery > NA.

Research progress of advanced microneedle drug delivery system and its application in biomedicine

Transdermal drug delivery is an effective way of drug delivery in addition to oral and intravenous administration. Among them, microneedle administration is a new type of subcutaneous drug delivery, which forms micron-level pores on the surface of the skin, making the drug enter the dermis through the cuticular layer of the skin in the least invasive way. This mode of drug delivery not only increases the permeation efficiency of transdermal drug delivery but also improves the bioavailability of drug delivery. At present, there are many kinds of research on microneedles, such as solid microneedles, hollow microneedles, soluble polymer microneedles, etc. However, some new microneedle drug delivery systems have been gradually developed and applied with the development of microneedle drug delivery technology, for meeting the more complex pathological environment. In this review, we focus on the principle, structure, and function of some new types of microneedles, such as stimulus-response microneedles, iontophoresis microneedles, and bionic microneedles. We summarize the effects of materials, geometry, and size on the properties of microneedles as well as their applications and potential developments in the field of biomedicine. We hope that this review can provide new ideas and help with the development of new microneedle drug delivery systems.

Tofacitinib combined with melanocyte protector α-MSH to treat vitiligo through dextran based hydrogel microneedles

Vitiligo can cause serious damage to the appearance of patients and affect physical and mental health, but there is currently no simple and effective treatment. According to the theory of autoimmune disorder, the separable hydrogel microneedles delivering alpha-melanocyte-stimulating hormone (α-MSH) and tofacitinib were designed to treat vitiligo. This hydrogel microneedles were formed by dextran methacrylate (DexMA) and cyclodextrin-adamantane based host-guest supramolecules (HGSM) through CC double bond polymerization and host-guest assembly. The microneedle tips formed by the double cross-linked hydrogel can pierce the stratum corneum and deliver melanocyte protector α-MSH and JAK inhibitor tofacitinib directly to the epidermis and dermis. Under the treatment of α-MSH/tofacitinib microneedles, massive deposition of melanin in epidermis and hair follicles significantly accelerated skin and hair pigmentation.

Supramolecular Dissolving Microneedle Patch Loading Hydrophobic Glucocorticoid for Effective Psoriasis Treatment

Glucocorticoid-based creams are commonly used for treatments of psoriatic skin lesions while showing poor permeation because the thickened stratum corneum severely limits drug absorption. Although dissolving microneedle (DMN) patches have been employed in treating skin disease by virtue of their direct target to the lesion site, conventional DMN patches are generally fabricated from the water-soluble matrix, making them difficult to efficiently encapsulate hydrophobic glucocorticoids. Here, we develop a mechanically robust supramolecular DMN composed of hydroxypropyl β-cyclodextrin (HPCD) to effectively and uniformly load triamcinolone acetonide (TA). The TA-loaded HPCD DMN (TAMN) exhibits excellent mechanical performance that can easily pierce the thickened psoriasis lesions and deliver TA efficiently. Owing to the increased water solubility and bioavailability of TA after inclusion into HPCD, TAMN shows a superior in vitro inhibitory effect on immortalized human keratinocyte (HaCaT) cells. Importantly, the administration of TAMN twice a week effectively alleviates psoriatic signs and reduces the expression of Ki67, IL-23, and IL-17 in the ear lesions of imiquimod-induced psoriasis-like mice. This supramolecular DMN provides a promising strategy for the efficient treatment of psoriasis and other skin diseases, greatly broadens the applications of supramolecular materials in transdermal drug delivery, and widens the range of drugs in DMNs.

Microneedles: structure, classification, and application in oral cancer theranostics

Oral cancer is a malignant tumor that threatens the health of individuals on a global scale. Currently available clinical treatment methods, including surgery, radiotherapy, and chemotherapy, significantly impact the quality of life of patients with systemic side effects. In the treatment of oral cancer, local and efficient delivery of antineoplastic drugs or other substances (like photosensitizers) to improve the therapy effect is a potential way to optimize oral cancer treatments. As an emerging drug delivery system in recent years, microneedles (MNs) can be used for local drug delivery, offering the advantages of high efficiency, convenience, and noninvasiveness. This review briefly introduces the structures and characteristics of various types of MNs and summarizes MN preparation methods. An overview of the current research application of MNs in different cancer treatments is provided. Overall, MNs, as a means of transporting substances, demonstrate great potential in oral cancer treatments, and their promising future applications and perspectives of MNs are outlined in this review.

Recent advances in long-acting drug delivery systems for anticancer drug

The use of systemic anticancer chemotherapy is intrinsically limited by its toxicity. Whether dealing with small molecules or biopharmaceuticals, after systemic administration, small doses fail to reach effective intratumoral concentrations, while high doses with significant tumor inhibition effects may also drive the death of healthy cells, endangering the patients. Therefore, strategies based on drug delivery systems (DDSs) for avoiding the systemic toxicity have been designed. Due to their ability to protect drugs from early elimination and control drug release, DDSs can foster tumor exposure to anticancer therapeutics by extending their circulation time or steadily releasing drugs into the tumor sites. However, approval of tailored DDSs systems for clinical use is minimal as the safety and the in vivo activity still need to be ameliorated by manipulating their physicochemical characteristics. During the last few years, several strategies have been described to improve their safety, stability, and fine-tune pharmaceuticals release kinetics. Herein, we reviewed the main DDSs, namely polymeric conjugates, nano or microparticles, hydrogels, and microneedles, explored for long-acting anticancer treatments, highlighting recently proposed modifications and their potential advantages for different anticancer therapies. Additionally, important limitations of long-acting anticancer therapies and future technology directions were also covered.

Human Albumin-Based Hydrogels for Their Potential Xeno-Free Microneedle Applications

Nowadays, hydrogels-based microneedles (MNs) have attracted a great interest owing to their outstanding qualities for biomedical applications. For the fabrication of hydrogels-based microneedles as tissue engineering scaffolds and drug delivery carriers, various biomaterials have been tested. They are required to feature tunable physiochemical properties, biodegradability, biocompatibility, nonimmunogenicity, high drug loading capacity, and sustained drug release. Among biomaterials, human proteins are the most ideal biomaterials for fabrication of hydrogels-based MNs; however, they are mechanically weak and poorly processible. To the best of the knowledge, there are no reports of xeno-free human protein-based MNs so far. Here, human albumin-based hydrogels and microneedles for tissue engineering and drug delivery by using relatively new processible human serum albumin methacryloyl (HSAMA) are engineered. The resultant HSAMA hydrogels display tunable mechanical properties, biodegradability, and good biocompatibility. Moreover, the xeno-free HSAMA microneedles display a sustained drug release profile and significant mechanical strength to penetrate the model skin. In vitro, they also show good biocompatibility and anticancer efficacy. Sustainable processible human albumin-based biomaterials may be employed as a xeno-free platform in vivo for tissue engineering and drug delivery in clinical trials in the future.

Egg Microneedle for Transdermal Delivery of Active Liraglutide

Liraglutide, a human glucagon-like peptide-1 (GLP-1) analog, is promising for safely treating type 2 diabetes mellitus (T2DM), compared to insulin, by significantly reducing the risk of glucose-dependent hypoglycemia. Concerns related to injection prevent T2DM patients from taking liraglutide regularly, even though once-a-day subcutaneous (SC) injections. Dissolving microneedles (DMNs) are promising substitutes for SC injection and for improving patient convenience. However, there are two fundamental limitations: the low drug delivery due to incomplete insertion and loss of drug activity during DMN fabrication. Here, it is shown that an egg microneedle (EMN) designed with three functional layered structures can maintain the maximum activity of the loaded compound during DMN fabrication and deliver it completely into the skin, with the base layer allowing the complete delivery of liraglutide, and the shell layer maintaining the drug activity by mimicking the role of albumin in eggs. In a diabetic mouse model, liraglutide administration via EMN exhibited similar effect when compared to that of injection. Therefore, EMN-mediated liraglutide administration is a good potential option for replacing liraglutide injections in T2DM treatment.

Bone-Targeted Dual Functional Lipid-coated Drug Delivery System for Osteosarcoma Therapy

PURPOSE OR OBJECTIVE

Osteosarcoma is well-known for its high incidence in children and adolescents and long-term bone pain, which seriously reduces the life quality of patients. Cisplatin (CDDP), as the first-line anti-osteosarcoma drug, has been used in many anticancer treatments. At the same time, the serious side effects of platinum (Pt) drugs have also attracted widespread attention. To accurately deliver Pt drugs to the lesion site and realize controlled release of Pt drugs, certain modified delivery systems have been extensively studied.

METHODS

Among them, liposomes have been approved for clinical cancer treatment due to their highly biocompatibility and superior modifiability. Here, we developed a bone-targeted dual functional lipid-coated drug delivery system, lipid-coated CDDP alendronate nanoparticles (LCA NPs) to target the bone and precisely deliver the drugs to the tumor site. Cell toxicity, apoptosis and cellular uptake were detected to evaluate the anticancer effect for LCA NPs. Furthermore, transwell assay and wound healing assay were conducted to estimate the osteosarcoma cell migration and invasion. Hemolysis assay was utilized to assess the biocapitibility of the kind of NPs.

RESULTS

With the aim of bone-targeted unit alendronate (ALD), LCA NPs serve as a rich bone homing Pt delivery system to exert efficient anticancer effects and synergistically reduce bone resorption and bone loss potentially.

CONCLUSIONS

By providing a highly biocompatible platform for osteosarcoma therapy, LCA NPs may help to significantly enhance the anticancer effect of Pt and greatly reduce the systemic toxicity and side effects of Pt towards osteosarcoma.

Revolutionizing Therapeutic Delivery with Microneedle Technology for Tumor Treatment

The tumor is an uncontrolled growth of tissue that can be localized (benign) or possesses the capability of metastasis (malignant). The conventional methods of tumor diagnosis, such as acupuncture, endoscopy, and histopathology, and treatment methods, such as injections, chemotherapy, surgery, and radiotherapy, are invasive, expensive, and pose severe safety and management issues for the patients. Microneedle technology is a recently developed approach for active transdermal drug delivery. It is minimally invasive, self-administrable, bypasses the first-pass effect, and effectively delivers chemotherapeutics and drugs at low doses, thus, overcoming the drawbacks of conventional delivery systems. This review provides an idea of the types, materials utilized in the fabrication, and techniques used for the preparation of microneedles (MNs), as well as their application in tumor diagnosis and treatment. Additionally, emphasis is given to the case studies related to MNs-assisted tumor therapy, such as photothermal therapy, gene therapy, photodynamic therapy, chemotherapy, immunotherapy, and various combination therapies. MNs also serve as a tool for diagnosis by the bio-sampling of blood and interstitial skin fluid, as well as biosensing various cancer biomarkers. The combined therapy and diagnostics provide theranostic MNs for enhanced and personalized tumor therapy. The limitations and prospects of MNs development are also discussed.

A spark to the powder keg: Microneedle-based antitumor nanomedicine targeting reactive oxygen species accumulation for chemodynamic/photothermal/chemotherapy

HYPOTHESIS

Chemodynamic therapy (CDT) can efficiently kill cancer cells by producing hydroxyl radical (•OH), a kind of high-toxic reactive oxygen species (ROS), via Fenton or Fenton-like reactions. This study involved a versatile nanomedicine, MSN@DOX/GA-Fe/PDA (M@DGP), delivered via microneedles, which was expected to combine chemodynamic/photothermal/chemotherapy and efficiently increase ROS accumulation to achieve significant therapeutic efficacy against melanoma.

EXPERIMENTS

The composition of the synthesized nanoparticles was confirmed by a series of characterizations including transmission electron microscopy, Fourier transform infrared spectroscopy, and zeta potential. The photothermal properties of the nanomedicine was evaluated via infrared imaging, and •OH-producing ability was evaluated by UV-Vis and electron spin resonance. The mechanisms of ROS accumulation were studied in B16 cells by detecting intracellular •OH, glutathione, and ROS levels. The drug-loaded microneedles (M@DGP-MNs) were prepared, and their morphology and mechanical strength were characterized. The in vivo antimelanoma effect and biosafety evaluation of the nanomedicine were investigated in tumor-bearing C57 mice.

FINDINGS

M@DGP was successfully prepared and could achieve ROS accumulation through a photothermal-enhanced Fenton reaction, polydopamine-induced glutathione consumption, and doxorubicin-mediated mitochondrial dysfunction which induced oxidative stress and apoptosis of tumor cells. M@DGP-MNs showed superior antitumor efficacy and good biosafety, providing a promising strategy for melanoma treatment.

Flexible polymeric patch based nanotherapeutics against non-cancer therapy

Flexible polymeric patches find widespread applications in biomedicine because of their biological and tunable features including excellent patient compliance, superior biocompatibility and biodegradation, as well as high loading capability and permeability of drug. Such polymeric patches are classified into microneedles (MNs), hydrogel, microcapsule, microsphere and fiber depending on the formed morphology. The combination of nanomaterials with polymeric patches allows for improved advantages of increased curative efficacy and lowered systemic toxicity, promoting on-demand and regulated drug administration, thus providing the great potential to their clinic translation. In this review, the category of flexible polymeric patches that are utilized to integrate with nanomaterials is briefly presented and their advantages in bioapplications are further discussed. The applications of nanomaterials embedded polymeric patches in non-cancerous diseases were also systematically reviewed, including diabetes therapy, wound healing, dermatological disease therapy, bone regeneration, cardiac repair, hair repair, obesity therapy and some immune disease therapy. Alternatively, the limitations, latest challenges and future perspectives of such biomedical therapeutic devices are addressed.

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The most explored polymeric patches, such as microneedle, hydrogel, microsphere, microcapsule, and fiber are summarized.

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Polymeric patches integrated with a diversity of nanomaterials are systematically overviewed in non-cancer therapy.

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The future prospective for the development of polymeric patch based nanotherapeutics is discussed.

Ameliorative impacts of polymeric and metallic nanoparticles on cisplatin-induced nephrotoxicity: a 2011-2022 review

Cisplatin (CDDP) is a well-known platinum-based drug used in the treatment of various malignancies. However, the widespread side effects that this drug leaves on normal tissues make its use limited. Since cisplatin is mainly eliminated from the kidneys, CDDP-induced nephrotoxicity is the most significant dose-limiting complication attributed to cisplatin, which often leads to dose withdrawal. Considering the high efficiency of cisplatin in chemotherapy, finding renoprotective drug delivery systems for this drug is a necessity. In this regard, we can take advantages of different nanoparticle-based approaches to deliver cisplatin into tumors either using passive targeting or using specific receptors. In an effort to find more effective cisplatin-based nano-drugs with less nephrotoxic effect, the current 2011-2022 review study was conducted to investigate some of the nanotechnology-based methods that have successfully been able to mitigate CDDP-induced nephrotoxicity. Accordingly, although cisplatin can cause renal failures through inducing mitochondria dysfunction, oxidative stress, lipid peroxidation and endoplasmic reticulum stress, some CDDP-based nano-carriers have been able to reverse a wide range of these advert effects. Based on the obtained results, it was found that the use of different metallic and polymeric nanoparticles can help renal cells to strengthen their antioxidant systems and stay alive through reducing CDDP-induced ROS generation, inhibiting apoptosis-related pathways and maintaining the integrity of the mitochondrial membrane. For example, nanocurcumin could inhibit oxidative stress and acting as a ROS scavenger. CONPs could reduce lipid peroxidation and pro-inflammatory cytokines. CDDP-loaded silver nanoparticles (AgNPs) could inhibit mitochondria-mediated apoptosis. In addition, tea polyphenol-functionalized SeNPs (Se@TE) NPs could mitigate the increased level of dephosphorylated AKT, phosphorylated p38 MAPK and phosphorylated c-Jun N-terminal kinase (JNK) induced by cisplatin. Moreover, exosomes mitigated cisplatin-induced renal damage through inhibiting Bcl2 and increasing Bim, Bid, Bax, cleaved caspase-9, and cleaved caspase-3. Hence, nanoparticle-based techniques are promising drug delivery systems for cisplatin so that some of them, such as lipoplatins and nanocurcumins, have even reached phases 1-3 trials.

Polymeric microneedles for enhanced drug delivery in cancer therapy

Microneedles (MNs) have attracted the interest of researchers. Polymeric MNs offer tremendous promise as drug delivery vehicles for bio-applications because of their high loading capacity, strong patient adherence, excellent biodegradability and biocompatibility, low toxicity, and extremely cheap cost. Incorporating enhanced-property nanomaterials into polymeric MNs matrix increases their features such as better mechanical strength, sustained drug delivery, lower toxicity, and higher therapeutic effects, therefore considerably increasing their biomedical application. This paper discusses polymeric MN fabrication techniques and the present status of polymeric MNs as a delivery method for enhanced drug delivery in cancer therapeutic applications. Furthermore, the opportunities and challenges of polymeric MNs for improved drug delivery in cancer therapy are highlighted.

Microneedle-mediated drug delivery for cutaneous diseases

Microneedles have garnered significant interest as transdermal drug delivery route owing to the advantages of nonselective loading capacity, minimal invasiveness, simple operation, and good biocompatibility. A number of therapeutics can be loaded into microneedles, including hydrophilic and hydrophobic small molecular drugs, and macromolecular drugs (proteins, mRNA, peptides, vaccines) for treatment of miscellaneous diseases. Microneedles feature with special benefits for cutaneous diseases owing to the direct transdermal delivery of therapeutics to the skin. This review mainly introduces microneedles fabricated with different technologies and transdermal delivery of various therapeutics for cutaneous diseases, such as psoriasis, atopic dermatitis, skin and soft tissue infection, superficial tumors, axillary hyperhidrosis, and plantar warts.

Integrating the microneedles with carboplatin to facilitate the therapeutic effect of radiotherapy for skin cancers

In most skin cancer patients, excisional surgery is required to remove tumorous tissue. However, the risk of locoregional recurrence after surgery alone is relatively high, particularly for a locally advanced stage of melanoma. Therefore, additional adjuvant treatments, such as radiotherapy, can be used after surgery to inhibit recurrent melanoma after surgical removal. To enhance local radiotherapy, we present the combined X-ray radiation and radiosensitizers (carboplatin) through microneedles (MNs) to treat melanoma. The MNs could be beneficial to precisely delivering carboplatin into the sub-epidermal layer of the melanoma region and alleviate patients' fear and discomfort during the drug administration compared to the traditional local injection. The carboplatin was loaded into the tips of dissolving gelatin MNs (carboplatin-MNs) through the molding method. The results show gelatin MNs have sufficient mechanical strength and can successfully administer carboplatin into the skin. Both in vitro and in vivo studies suggest that carboplatin can enhance radiotherapy in melanoma treatment. With a combination of radiotherapy and carboplatin, the inhibition effect of carboplatin delivered into the B16F10 murine melanoma model through MNs administration (1.2 mg/kg) is equivalent to that through an intravenous route (5 mg/kg). The results demonstrate a promise of combined carboplatin and X-ray radiation treatment in treating melanoma by MNs administration.

Self-targeting platinum(IV) amphiphilic prodrug nano-assembly as radiosensitizer for synergistic and safe chemoradiotherapy of hepatocellular carcinoma

Chemoradiotherapy is a widely used treatment for patients with malignancies such as hepatocellular carcinoma (HCC). However, it remains challenging to realize safe and synergistic chemotherapy and radiation sensitization. Herein, we design a self-targeting nano-assembly (STNA) based on platinum(IV)-lactose amphiphilic prodrug for synergistic and safe chemoradiotherapy of HCC. The Pt STNA would improve the tumor accumulation due to the targeting ability of lactose to HCC cells. After receptor-mediated endocytosis, Pt STNA would release cisplatin(II) in cancer cells to form DNA-binding, thus inducing DNA damage and cell apoptosis. Meanwhile, the DNA-binding also causes cell cycle arrest in the radiation-sensitive G2/M phase by the up-regulation of phosphorylated checkpoint kinase 1 (p-Chk1) expression. Furthermore, under X-ray irradiation, Pt STNA as radiosensitizer possesses a strong X-ray attenuation ability to deposit more energy, thus elevating the level of reactive oxygen species (ROS) to amplify the cell-killing effect of radiotherapy in the G2/M phase with increased DNA damage. As a result, Pt STNA exhibits significant synergistic therapeutic effects in chemoradiotherapy with no adverse effects in vitro and in vivo. Overall, we present a novel self-targeting nano-assembly strategy based on widely used Pt drugs for synergistic chemotherapy and radiation sensitization of HCC treatment.

A nanoengineered topical transmucosal cisplatin delivery system induces anti-tumor response in animal models and patients with oral cancer

Despite therapeutic advancements, oral cavity squamous cell carcinoma (OCSCC) remains a difficult disease to treat. Systemic platinum-based chemotherapy often leads to dose-limiting toxicity (DLT), affecting quality of life. PRV111 is a nanotechnology-based system for local delivery of cisplatin loaded chitosan particles, that penetrate tumor tissue and lymphatic channels while avoiding systemic circulation and toxicity. Here we evaluate PRV111 using animal models of oral cancer, followed by a clinical trial in patients with OCSCC. In vivo, PRV111 results in elevated cisplatin retention in tumors and negligible systemic levels, compared to the intravenous, intraperitoneal or intratumoral delivery. Furthermore, PRV111 produces robust anti-tumor responses in subcutaneous and orthotopic cancer models and results in complete regression of carcinogen-induced premalignant lesions. In a phase 1/2, open-label, single-arm trial (NCT03502148), primary endpoints of efficacy (≥30% tumor volume reduction) and safety (incidence of DLTs) of neoadjuvant PRV111 were reached, with 69% tumor reduction in ~7 days and over 87% response rate. Secondary endpoints (cisplatin biodistribution, loco-regional control, and technical success) were achieved. No DLTs or drug-related serious adverse events were reported. No locoregional recurrences were evident in 6 months. Integration of PRV111 with current standard of care may improve health outcomes and survival of patients with OCSCC.

Recent advances in nanotechnology based combination drug therapy for skin cancer

Skin-cancer (SC) is more common than all other cancers affecting large percentage of the population in the world and is increasing in terms of morbidity and mortality. In the United States, 3million people are affected by SC annually whereas millions of people are affected globally. Melanoma is fifth most common cancer in the United States. SC is commonly occurred in white people as per WHO. SC is divided into two groups, i.e. melanoma and non-melanoma. In the previous two decades, management of cancer remains to be a tough and a challenging task for many scholars. Presently, the treatment protocols are mostly based on surgery and chemo-radiation therapy, which sooner or later harm the unaffected cells too. To reduce these limitations, nano scaled materials and its extensive range may be recognized as the probable carriers for the selective drug delivery in response to cancerous cells. Recently, the nanocarriers based drugs and their combinations were found to be a new and interesting approach of study for the management of skin carcinoma to enhance the effectiveness, to lessen the dose-dependent side effects and to avoid the drug resistance. This review may emphasize on the wide-range of information on nanotechnology-based drugs and their combination with physical techniques.

Semi-Implantable Bioelectronics

Developing techniques to effectively and real-time monitor and regulate the interior environment of biological objects is significantly important for many biomedical engineering and scientific applications, including drug delivery, electrophysiological recording and regulation of intracellular activities. Semi-implantable bioelectronics is currently a hot spot in biomedical engineering research area, because it not only meets the increasing technical demands for precise detection or regulation of biological activities, but also provides a desirable platform for externally incorporating complex functionalities and electronic integration. Although there is less definition and summary to distinguish it from the well-reviewed non-invasive bioelectronics and fully implantable bioelectronics, semi-implantable bioelectronics have emerged as highly unique technology to boost the development of biochips and smart wearable device. Here, we reviewed the recent progress in this field and raised the concept of "Semi-implantable bioelectronics", summarizing the principle and strategies of semi-implantable device for cell applications and in vivo applications, discussing the typical methodologies to access to intracellular environment or in vivo environment, biosafety aspects and typical applications. This review is meaningful for understanding in-depth the design principles, materials fabrication techniques, device integration processes, cell/tissue penetration methodologies, biosafety aspects, and applications strategies that are essential to the development of future minimally invasive bioelectronics.

Microneedles in Action: Microneedling and Microneedles-Assisted Transdermal Delivery

Human skin is a multilayered physiochemical barrier protecting the human body. The stratum corneum (SC) is the outermost keratinized layer of skin through which only molecules with less or equal to 500 Da (Dalton) in size can freely move through the skin. Unfortunately, the conventional use of a hypothermic needle for large therapeutic agents is susceptible to needle phobia and the risk of acquiring infectious diseases. As a new approach, a microneedle (MN) can deliver therapeutically significant molecules without apparent limitations associated with its molecular size. Microneedles can create microchannels through the skin’s SC without stimulating the proprioceptive pain nerves. With recent technological advancements in both fabrication and drug loading, MN has become a versatile platform that improves the efficacy of transdermally applied therapeutic agents (TAs) and associated treatments for various indications. This review summarizes advanced fabrication techniques for MN and addresses numerous TA coating and TA elution strategies from MN, offering a comprehensive perspective on the current microneedle technology. Lastly, we discuss how microneedling and microneedle technologies can improve the clinical efficacy of a variety of skin diseases.

“Pincer movement”: Reversing cisplatin resistance based on simultaneous glutathione depletion and glutathione S-transferases inhibition by redox-responsive degradable organosilica hybrid nanoparticles

The therapeutic efficacy of cisplatin has been restricted by drug resistance of cancers. Intracellular glutathione (GSH) detoxification of cisplatin under the catalysis of glutathione S-transferases (GST) plays important roles in the development of cisplatin resistance. Herein, a strategy of “pincer movement” based on simultaneous GSH depletion and GST inhibition is proposed to enhance cisplatin-based chemotherapy. Specifically, a redox-responsive nanomedicine based on disulfide-bridged degradable organosilica hybrid nanoparticles is developed and loaded with cisplatin and ethacrynic acid (EA), a GST inhibitor. Responding to high level of intracellular GSH, the hybrid nanoparticles can be gradually degraded due to the break of disulfide bonds, which further promotes drug release. Meanwhile, the disulfide-mediated GSH depletion and EA-induced GST inhibition cooperatively prevent cellular detoxification of cisplatin and reverse drug resistance. Moreover, the nanomedicine is integrated into microneedles for intralesional drug delivery against cisplatin-resistant melanoma. The in vivo results show that the nanomedicine-loaded microneedles can achieve significant GSH depletion, GST inhibition, and consequent tumor growth suppression. Overall, this research provides a promising strategy for the construction of new-type nanomedicines to overcome cisplatin resistance, which extends the biomedical application of organosilica hybrid nanomaterials and enables more efficient chemotherapy against drug-resistant cancers.

Recent advances in polymer microneedles for drug transdermal delivery: Design strategies and applications

In recent years, the transdermal drug delivery based on microneedles (MNs) technology has received extensive attention, which offers a safer and painless alternative to hypodermic needle injection. They can pierce the stratum corneum and deliver drugs to the epidermis and dermis-structures of skin, showing prominent properties such as minimally invasive, bypassing first-pass metabolism, and self-administered. A range of materials have been used to fabricate MNs, such as silicon, metal, glass, and polymers. Among them, polymer MNs have gained increasing attention from pharmaceutical and cosmetic companies as one of the promising drug delivery methods. Microneedle products have recently become available on the market, and some of them are under evaluation for efficacy and safety. This paper focuses on current state of polymer MNs in the drug transdermal delivery. The materials and methods for the fabrication of polymer MNs and their drug administration are described. The recent progresses of polymer MNs for treatment of cancer, vaccine delivery, blood glucose regulation, androgenetic alopecia, obesity, tissue healing, myocardial infarction and gout are reviewed. The challenges of MNs technology are summarized and the future development trend of MNs is also prospected. This article is protected by copyright. All rights reserved.

Microneedle-Mediated Transdermal Delivery of Drug-Carrying Nanoparticles

Drug-carrying nanoparticles have obtained great attention for disease treatments due to the fact that they can improve drug solubility, provide drug protection and prolong release duration, thus enhancing drug bioavailability and increasing therapeutic efficacy. Although nanoparticles containing drugs can be administered via different routes such as oral, intravenous and ocular, transdermal delivery of nanoparticles mediated by microneedles has attracted considerable interest due to the capability of circumventing enzymatic degradation caused by gastrointestinal track, and increasing patient compliance by reducing pain associated with hypodermic injection. In this review, we first introduce four types of nanoparticles that were used for drug delivery, and then summarize strategies that have been employed to facilitate delivery of drug-loaded nanoparticles via microneedles. Finally, we give a conclusion and provide our perspectives on the potential clinical translation of microneedle-facilitated nanoparticles delivery.

Microneedle-Based Natural Polysaccharide for Drug Delivery Systems (DDS): Progress and Challenges

In this focused progress review, the most widely accepted methods of transdermal drug delivery are hypodermic needles, transdermal patches and topical creams. However, microneedles (MNs) (or microneedle arrays) are low-invasive 3D biomedical constructs that bypass the skin barrier and produce systemic and localized pharmacological effects. In the past, biomaterials such as carbohydrates, due to their physicochemical properties, have been extensively used to manufacture microneedles (MNs). Due to their wide range of functional groups, carbohydrates enable the design and development of tunable properties and functionalities. In recent years, numerous microneedle products have emerged on the market, although much research needs to be undertaken to overcome the various challenges before the successful introduction of microneedles into the market. As a result, carbohydrate-based microarrays have a high potential to achieve a future step in sensing, drug delivery, and biologics restitution. In this review, a comprehensive overview of carbohydrates such as hyaluronic acid, chitin, chitosan, chondroitin sulfate, cellulose and starch is discussed systematically. It also discusses the various drug delivery strategies and mechanical properties of biomaterial-based MNs, the progress made so far in the clinical translation of carbohydrate-based MNs, and the promotional opportunities for their commercialization. In conclusion, the article summarizes the future perspectives of carbohydrate-based MNs, which are considered as the new class of topical drug delivery systems.

Skin cancer biology and barriers to treatment: Recent applications of polymeric micro/nanostructures

Background

Skin cancer has been the leading type of cancer worldwide. Melanoma and non-melanoma skin cancers are now the most common types of skin cancer that have been reached to epidemic proportion. Based on the rapid prevalence of skin cancers, and lack of efficient drug delivery systems, it is essential to surge the possible ways to prevent or cure the disease.

Aim of review

Although surgical modalities and therapies have been made great progress in recent years, however, there is still an urgent need to alleviate its increased burden. Hence, understanding the precise pathophysiological signaling mechanisms and all other factors of such skin insults will be beneficial for the development of more efficient therapies.

Key scientific concepts of review

In this review, we explained new understandings about onset and development of skin cancer and described its management via polymeric micro/nano carriers-based therapies, highlighting the current key bottlenecks and future prospective in this field. In therapeutic drug/gene delivery approaches, polymeric carriers-based system is the most promising strategy. This review discusses that how polymers have successfully been exploited for development of micro/nanosized systems for efficient delivery of anticancer genes and drugs overcoming all the barriers and limitations associated with available conventional therapies. In addition to drug/gene delivery, intelligent polymeric nanocarriers platforms have also been established for combination anticancer therapies including photodynamic and photothermal, and for theranostic applications. This portfolio of latest approaches could promote the blooming growth of research and their clinical availability.

Wearable Electrochemical Sensors in Parkinson's Disease

Parkinson’s disease (PD) is a neurodegenerative disorder associated with widespread aggregation of α-synuclein and dopaminergic neuronal loss in the substantia nigra pars compacta. As a result, striatal dopaminergic denervation leads to functional changes in the cortico-basal-ganglia-thalamo-cortical loop, which in turn cause most of the parkinsonian signs and symptoms. Despite tremendous advances in the field in the last two decades, the overall management (i.e., diagnosis and follow-up) of patients with PD remains largely based on clinical procedures. Accordingly, a relevant advance in the field would require the development of innovative biomarkers for PD. Recently, the development of miniaturized electrochemical sensors has opened new opportunities in the clinical management of PD thanks to wearable devices able to detect specific biological molecules from various body fluids. We here first summarize the main wearable electrochemical technologies currently available and their possible use as medical devices. Then, we critically discuss the possible strengths and weaknesses of wearable electrochemical devices in the management of chronic diseases including PD. Finally, we speculate about possible future applications of wearable electrochemical sensors in PD, such as the attractive opportunity for personalized closed-loop therapeutic approaches.

Bioimaging of Dissolvable Microneedle Arrays: Challenges and Opportunities

The emergence of microneedle arrays (MNAs) as a novel, simple, and minimally invasive administration approach largely addresses the challenges of traditional drug delivery. In particular, the dissolvable MNAs act as a promising, multifarious, and well-controlled platform for micro-nanotransport in medical research and cosmetic formulation applications. The effective delivery mostly depends on the behavior of the MNAs penetrated into the body, and accurate assessment is urgently needed. Advanced imaging technologies offer high sensitivity and resolution visualization of cross-scale, multidimensional, and multiparameter information, which can be used as an important aid for the evaluation and development of new MNAs. The combination of MNA technology and imaging can generate considerable new knowledge in a cost-effective manner with regards to the pharmacokinetics and bioavailability of active substances for the treatment of various diseases. In addition, noninvasive imaging techniques allow rapid, receptive assessment of transdermal penetration and drug deposition in various tissues, which could greatly facilitate the translation of experimental MNAs into clinical application. Relying on the recent promising development of bioimaging, this review is aimed at summarizing the current status, challenges, and future perspective on in vivo assessment of MNA drug delivery by various imaging technologies.