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Journal of Materials Chemistry. B Aug 2022Microneedles (MNs) have been developed for various applications such as drug delivery, cosmetics, diagnosis, and biosensing. To meet the requirements of MNs used in... (Review)
Review
Microneedles (MNs) have been developed for various applications such as drug delivery, cosmetics, diagnosis, and biosensing. To meet the requirements of MNs used in these areas, numerous materials have been used for the fabrication of MNs. However, MNs will be exposed to skin tissues after piercing the stratum corneum barrier. Thus, it is necessary to ensure that the matrix materials of MNs have the characteristics of low toxicity, good biocompatibility, biodegradability, and sufficient mechanical properties for clinical application. In this review, the matrix materials currently used for preparing MNs are summarized and reviewed in terms of these factors. In addition, MN products used on the market and their applications are summarized in the end. This work may provide some basic information to researchers in the selection of MN matrix materials and in developing new materials.
Topics: Administration, Cutaneous; Biocompatible Materials; Microinjections; Needles; Skin
PubMed: 35916308
DOI: 10.1039/d2tb00905f -
Biomaterials Jan 2021Transdermal drug delivery exhibited encouraging prospects, especially through superficial drug administration routes. However, only a few limited lipophilic drug... (Review)
Review
Transdermal drug delivery exhibited encouraging prospects, especially through superficial drug administration routes. However, only a few limited lipophilic drug molecules could cross the skin barrier, those are with low molecular weight and rational Log P value. Microneedles (MNs) can overcome these limitations to deliver numerous drugs into the dermal layer by piercing the outermost skin layer of the body. In the case of superficial cancer treatments, topical drug administration faces severely low transfer efficiency, and systemic treatments are always associated with side effects and premature drug degradation. MN-based systems have achieved excellent technical capabilities and been tested for pre-clinical chemotherapy, photothermal therapy, photodynamic therapy, and immunotherapy. In this review, we will focus on the features, progress, and opportunities of MNs in the anticancer drug delivery system. Then, we will discuss the strategies and advantages in these works and summarize challenges, perspectives, and translational potential for future applications.
Topics: Administration, Cutaneous; Antineoplastic Agents; Drug Delivery Systems; Microinjections; Needles; Pharmaceutical Preparations
PubMed: 32979655
DOI: 10.1016/j.biomaterials.2020.120410 -
Therapeutic Delivery 2015Microneedles are tiny micron-sized structures, made of a variety of materials, used to minimally disrupt the outermost layer of the skin for enhancing the delivery of... (Review)
Review
Microneedles are tiny micron-sized structures, made of a variety of materials, used to minimally disrupt the outermost layer of the skin for enhancing the delivery of therapeutic molecules across the skin. They are sufficiently long enough just to breach the stratum corneum barrier but too short to reach the nerve endings that perceive pain. Treating the skin using microneedles results in the creation of aqueous microchannels that promote delivery of molecules practically of any size. Small molecules, proteins, vaccines and diagnostic agents can be delivered using microneedles. This technology that has started with microstructures made of metal and silicon has now undergone significant advances in the last decade and currently there are microneedle products in the market.
Topics: Animals; Drug Delivery Systems; Humans; Microinjections; Nanotechnology; Needles; Skin
PubMed: 26419290
DOI: 10.4155/tde.15.67 -
Pharmaceutical Research Oct 2022Gene therapy is one of the most widely studied treatments and has the potential to treat a variety of intractable diseases. The skin's limited permeability, as the... (Review)
Review
Gene therapy is one of the most widely studied treatments and has the potential to treat a variety of intractable diseases. The skin's limited permeability, as the body's initial protective barrier, drastically inhibits the delivery effect of gene medicine. Given the potential adverse effects and physicochemical features of the medications, improving generic drug penetration into the skin barrier and achieving an effective level of target tissues remains a challenge. Microneedles have made tremendous improvements in aided gene transfer and medication delivery as a unique method. Microneedles offer the advantage of being minimally invasive and painless, as well as the ability to distribute gene medicines straight through the stratum corneum. Microneedles have been used to penetrate skin tissue with various nucleic acids and medicines in recent years, allowing for a wide range of applications in the treatment of skin ailments. This review focuses on skin-related disorders and immunity, and it primarily discusses the progress of microneedle transdermal gene therapy in recent years. It also complements the current major vectors and related microneedle gene therapy applications.
Topics: Administration, Cutaneous; Drug Delivery Systems; Drugs, Generic; Genetic Therapy; Microinjections; Needles; Nucleic Acids; Pharmaceutical Preparations; Skin
PubMed: 36008737
DOI: 10.1007/s11095-022-03376-x -
STAR Protocols Dec 2020Since its first application for site-directed mutagenesis, the CRISPR-Cas9 system has revolutionized genome engineering. Here, we present a validated workflow for the...
Since its first application for site-directed mutagenesis, the CRISPR-Cas9 system has revolutionized genome engineering. Here, we present a validated workflow for the generation of targeted genomic deletions in zebrafish, including the design, cloning, and synthesis of single-guide RNAs and Cas9 mRNA, followed by microinjection in zebrafish embryos and subsequent genotype screening for the establishment of a mutant line. The versatility and efficiency of this pipeline makes the generation of zebrafish models a widely used approach in functional genetics. For complete details on the use and execution of this protocol, please refer to Amorim et al. (2020).
Topics: Animals; CRISPR-Cas Systems; Gene Editing; Genetic Engineering; Genome; Genomics; Microinjections; Mutagenesis, Site-Directed; RNA, Guide, CRISPR-Cas Systems; Sequence Deletion; Zebrafish
PubMed: 33377102
DOI: 10.1016/j.xpro.2020.100208 -
Journal of Visualized Experiments : JoVE Aug 2019Altering gene function in a developing organism is central to different kinds of experiments. While tremendously powerful genetic tools have been developed in...
Altering gene function in a developing organism is central to different kinds of experiments. While tremendously powerful genetic tools have been developed in traditional model systems, it is difficult to manipulate genes or messenger RNA (mRNA) in most other organisms. At the same time, evolutionary and comparative approaches rely on an exploration of gene function in many different species, necessitating the development and adaptation of techniques for manipulating expression outside currently genetically tractable species. This protocol describes a method for injecting reagents into cricket eggs to assay the effects of a given manipulation on embryonic or larval development. Instructions for how to collect and inject eggs with beveled needles are described. This relatively straightforward technique is flexible and potentially adaptable to other insects. One can gather and inject dozens of eggs in a single experiment, and survival rates for buffer-only injections improve with practice and can be as high as 80%. This technique will support several types of experimental approaches including injection of pharmacological agents, in vitro capped mRNA to express genes of interest, double-stranded RNA (dsRNA) to achieve RNA interference, use of clustered regularly interspaced short palindromic repeats (CRISPR) in concert with CRISPR-associated protein 9 (Cas9) reagents for genomic modification, and transposable elements to generate transient or stable transgenic lines.
Topics: Animals; CRISPR-Cas Systems; Gryllidae; Microinjections; Needles; Ovum
PubMed: 31498320
DOI: 10.3791/59726 -
Drug Delivery and Translational Research Aug 2021Transdermal drug delivery systems (TDDS) have many advantages and represent an excellent alternative to oral delivery and hypodermic injections. TDDS are more convenient... (Review)
Review
Transdermal drug delivery systems (TDDS) have many advantages and represent an excellent alternative to oral delivery and hypodermic injections. TDDS are more convenient and less invasive tools for disease and viral infection treatment, prevention, detection, and surveillance. The emerging development of microneedles for TDDS has facilitated improved skin barrier penetration for the delivery of macromolecules or hydrophilic drugs. Microneedle TDDS patches can be fabricated to deliver virus vaccines and potentially provide a viable alternative vaccine modality that offers improved immunogenicity, thermostability, simplicity, safety, and compliance as well as sharp-waste reduction, increased cost-effectiveness, and the capacity for self-administration, which could improve vaccine distribution. These advantages make TDDS-based vaccine delivery an especially well-suited option for treatment of widespread viral infectious diseases including pandemics. Because microneedle-based bioassays employ transdermal extraction of interstitial fluid or blood, they can be used as a minimally invasive approach for surveying disease markers and providing point-of-care (POC) diagnostics. For cutaneous viral infections, TDDS can provide localized treatment with high specificity and less systemic toxicity. In summary, TDDS, especially those that employ microneedles, possess special attributes that can be leveraged to reduce morbidity and mortality from viral infectious diseases. In this regard, they may have considerable positive impact as a modality for improving global health. In this article, we introduce the possible role and summarize the current literature regarding TDDS applications for fighting common cutaneous or systemic viral infectious diseases, including herpes simplex, varicella or herpes zoster, warts, influenza, measles, and COVID-19.
Topics: Administration, Cutaneous; Animals; Antiviral Agents; COVID-19; Communicable Diseases; Drug Delivery Systems; Humans; Microinjections; COVID-19 Drug Treatment
PubMed: 34024014
DOI: 10.1007/s13346-021-01004-6 -
Advanced Drug Delivery Reviews Jul 2018The manipulation of single cells and whole tissues has been possible since the early 70's, when semi-automatic injectors were developed. Since then, microinjection has... (Review)
Review
The manipulation of single cells and whole tissues has been possible since the early 70's, when semi-automatic injectors were developed. Since then, microinjection has been used to introduce an ever-expanding range of colloids of up to 1000 nm in size into living cells. Besides injecting nucleic acids to study transfection mechanisms, numerous cellular pathways have been unraveled through the introduction of recombinant proteins and blocking antibodies. The injection of nanoparticles has also become popular in recent years to investigate toxicity mechanisms and intracellular transport, and to conceive semi-synthetic cells containing artificial organelles. This article reviews colloidal systems such as proteins, nucleic acids and nanoparticles that have been injected into cells for different research aims, and discusses the scientific advances achieved through them. The colloids' intracellular processing and ultimate fate are also examined from a drug delivery perspective with an emphasis on the differences observed for endocytosed versus microinjected material.
Topics: Colloids; Drug Delivery Systems; Humans; Microinjections; Nanoparticles; Nucleic Acids; Proteins
PubMed: 29935217
DOI: 10.1016/j.addr.2018.06.013 -
Drug Delivery and Translational Research Aug 2015The advent of microneedle (MN) technology has provided a revolutionary platform for the delivery of therapeutic agents, particularly in the field of gene therapy. For... (Review)
Review
The advent of microneedle (MN) technology has provided a revolutionary platform for the delivery of therapeutic agents, particularly in the field of gene therapy. For over 20 years, the area of gene therapy has undergone intense innovation and progression which has seen advancement of the technology from an experimental concept to a widely acknowledged strategy for the treatment and prevention of numerous disease states. However, the true potential of gene therapy has yet to be achieved due to limitations in formulation and delivery technologies beyond parenteral injection of the DNA. Microneedle-mediated delivery provides a unique platform for the delivery of DNA therapeutics clinically. It provides a means to overcome the skin barriers to gene delivery and deposit the DNA directly into the dermal layers, a key site for delivery of therapeutics to treat a wide range of skin and cutaneous diseases. Additionally, the skin is a tissue rich in immune sentinels, an ideal target for the delivery of a DNA vaccine directly to the desired target cell populations. This review details the advancement of MN-mediated DNA delivery from proof-of-concept to the delivery of DNA encoding clinically relevant proteins and antigens and examines the key considerations for the improvement of the technology and progress into a clinically applicable delivery system.
Topics: DNA; Equipment Design; Gene Transfer Techniques; Genetic Therapy; Humans; Microinjections; Needles; Skin
PubMed: 26122168
DOI: 10.1007/s13346-015-0243-1 -
Tissue Engineering. Part B, Reviews Jun 2023Wrinkled and loose skin resulting from collagen degradation along with fibers decreasing reflects the youth diminishing. Microneedles (MNs) have opened up new avenues... (Review)
Review
Wrinkled and loose skin resulting from collagen degradation along with fibers decreasing reflects the youth diminishing. Microneedles (MNs) have opened up new avenues for the development of painless and noninvasive transdermal drug delivery systems for facial rejuvenation. Encapsulated drugs or molecules are transmitted to targeted tissues via percutaneous microchannels, which eliminate potential gastric stimulation or first-pass metabolic effects, as well as boost patient compliance. Although MNs are considered effective and feasible therapeutic alternatives to metals, silicon, and polymers, traditional procedures with reduction processes continue to encounter methodological limitations. In recent years, promising additive manufacturing processes such as three-dimensional printing and two-photon polymerization manufacturing have been developed with the aim of overcoming the limitations by traditional processes to facilitate an efficient and economic production mode. This review summarizes the design, material selection, and manufacturing method for recently advanced MN systems. Furthermore, we also highlight specific polymeric or natural microneedle products, like hyaluronan, plant derivates, and vitamins, for esthetic applications in this review. Impact Statement In this review, the materials and manufactural routes of microneedles (MNs) are detailed. Moreover, similar to the diagnostic or therapeutic MNs, the feature of dispensation with training and ready-to-use is perfect for beautification and anti-aging, which necessitate repeated and long-term usage. Furthermore, the specific polymeric or natural products for esthetic applications of MNs are highlighted in this review.
Topics: Humans; Adolescent; Skin; Drug Delivery Systems; Delayed-Action Preparations; Rejuvenation; Microinjections; Polymers
PubMed: 36200631
DOI: 10.1089/ten.TEB.2022.0131