Heterogeneous polymer composite nanoparticles loaded in situ gel for controlled release intra-vaginal therapy of genital herpes

Effect of aluminium oxide nanoparticles on long-acting oleogels laden with Sc-PLA-chitosan nanoparticles for anti-HIV therapy

The development of a long-acting injectable drug delivery systems (DDS) of active pharmaceutical ingredients (API) holds great promise in addressing the challenges of treatment adherence, predominantly in HIV/AIDS. Polymers are inevitable carriers for the preparation of DDS, which are typically composed of polylactide (PLA), carbohydrates such as chitosan or cellulose derivatives. In this study, the tenofovir alafenamide (TAF) laden PLA-stereocomplex-chitosan nanoparticles (Sc-PLA-chitosan NPs) were developed through the spray-dried technique. These NPs had a mean particle size of 91 ± 8 nm and were incorporated into oleogels consisting of sesame oil and ethyl-cellulose. To enhance the syringeability of highly viscous oleogels, the commercially available aluminium oxide NPs were added with a size of 78 nm. The proposed DDS exhibits prolonged sustained release for up to 12 days in phosphate buffer pH 7.4. Noteworthy, the oleogels with Sc-PLA-chitosan NPs displayed extended tissue permeation properties indicating their potential long-acting in-vivo drug release. Collectively, this study recommends that the development of Sc-PLA-chitosan NPs-loaded oleogels represents a certainly adaptable long-acting injectables system for the delivery of APIs in the context of HIV/AIDS. This system is expected to contribute to improved and effective treatment adherence among patients infected with HIV and provide requisite therapeutic outcomes.

Polymer-Based Nanoparticles as Drug Delivery Systems for Purines of Established Importance in Medicine

Many purine derivatives are active pharmaceutical ingredients of significant importance in the therapy of autoimmune diseases, cancers, and viral infections. In many cases, their medical use is limited due to unfavorable physicochemical and pharmacokinetic properties. These problems can be overcome by the preparation of the prodrugs of purines or by combining these compounds with nanoparticles. Herein, we aim to review the scientific progress and perspectives for polymer-based nanoparticles as drug delivery systems for purines. Polymeric nanoparticles turned out to have the potential to augment antiviral and antiproliferative effects of purine derivatives by specific binding to receptors (ASGR1-liver, macrophage mannose receptor), increase in drug retention (in eye, intestines, and vagina), and permeation (intranasal to brain delivery, PEPT1 transport of acyclovir). The most significant achievements of polymer-based nanoparticles as drug delivery systems for purines were found for tenofovir disoproxil in protection against HIV, for acyclovir against HSV, for 6-mercaptopurine in prolongation of mice ALL model life, as well as for 6-thioguanine for increased efficacy of adoptively transferred T cells. Moreover, nanocarriers were able to diminish the toxic effects of acyclovir, didanosine, cladribine, tenofovir, 6-mercaptopurine, and 6-thioguanine.

Imiquimod-Loaded Chitosan-Decorated Di-Block and Tri-Block Polymeric Nanoparticles Loaded In Situ Gel for the Management of Cervical Cancer

BACKGROUND

Cervical intraepithelial neoplasia, the predisposing factor for cervical cancer (CC), is caused by human papillomavirus (HPV) infection and can be treated with imiquimod (IMQ). However, poor water solubility and side effects such as local inflammation can render IMQ ineffective. The aim of this study is to design a prolonged release nano system in combination with mucoadhesive-thermosensitive properties for an effective vaginal drug delivery.

METHODS

Polylactic-co-glycolic acid (PLGA), polycaprolactone (PCL), poly lactide-co-caprolactone (PLA-PCL), and poly L-lactide-co-caprolactone-co-glycolide (PLGA-PCL) were used to create IMQ nanoparticles. Chitosan (CS) was then added to the surfaces of the IMQ NPs for its mucoadhesive properties. The NPs were then incorporated into poloxamer hydrogels. The NPs' size and morphology, encapsulation efficiency (EE), in vitro drug release, gel characterization, ex vivo drug permeation, and in vitro safety and efficacy were characterized.

RESULTS

Two batches of NPs were prepared, IMQ NPs and CS-coated NPs (CS-IMQ NPs). In general, both types of NPs were uniformly spherical in shape with average particle sizes of 237.3 ± 4.7 and 278.2 ± 5.4 nm and EE% of 61.48 ± 5.19% and 37.73 ± 2.88 for IMQ NPs and CS-IMQ NPs, respectively. Both systems showed prolonged drug release of about 80 and 70% for IMQ NPs and CS-IMQ NPs, respectively, within 48 h. The gelation temperatures for the IMQ NPs and CS-IMQ NPs were 30 and 32 °C, respectively; thus, suitable for vaginal application. Although ex vivo permeability showed that CS-IMQ NPs showed superior penetration compared to IMQ NPs, both systems enhanced drug penetration (283 and 462 µg/cm2 for IMQ NPs and CS-IMQ NPs, respectively) relative to the control (60 µg/cm2). Both systems reduced the viability of cervical cancer cells, with a minimal effect of the normal vaginal epithelium. However, IMQ NPs exhibited a more pronounced cytotoxic effect. Both systems were able to reduce the production of inflammatory cytokines by at least 25% in comparison to free IMQ.

CONCLUSION

IMQ and CS-IMQ NP in situ gels enhanced stability and drug release, and improved IMQ penetration through the vaginal tissues. Additionally, the new systems were able to increase the cytotoxic effect of IMQ against CC cells with a reduction in inflammatory responses. Thus, we believe that these systems could be a good alternative to commercial IMQ systems for the management of CC.

Polymer based dual drug delivery system for targeted treatment of fluoroquinolone resistant Staphylococcus aureus mediated infections

The present study attempts to treat S. aureus-induced soft skin infections using a combinatorial therapy with an antibiotic, Ciprofloxacin (CIP), and an efflux pump inhibitor 5-Nitro-2-(3-phenylpropoxy) pyridine (5-NPPP) through a smart hydrogel delivery system. The study aims to reduce the increasing rates of infections and antimicrobial resistance; therefore, an efflux pump inhibitor molecule is synthesized and delivered along with an antibiotic to re-sensitize the pathogen towards antibiotics and treat the infections. CIP-loaded polyvinyl alcohol (PVA) hydrogels at varying concentrations were fabricated and optimized by a chemical cross-linking process, which exhibited sustained drug release for 5 days. The compound 5-NPPP loaded hydrogels provided linear drug release for 2 days, necessitating the need for the development of polymeric nanoparticles to alter the release drug pattern. 5-NPPP loaded Eudragit RSPO nanoparticles were prepared by modified nanoprecipitation-solvent evaporation method, which showed optimum average particle size of 230-280 nm with > 90% drug entrapment efficiency. The 5-NPPP polymeric nanoparticles loaded PVA hydrogels were fabricated to provide a predetermined sustained release of the compound to provide a synergistic effect. The selected 7% PVA hydrogels loaded with the dual drugs were evaluated using Balb/c mice models induced with S. aureus soft skin infections. The results of in vivo studies were evidence that the dual drugs loaded hydrogels were non-toxic and reduced the bacterial load causing re-sensitization towards antibiotics, which could initiate re-epithelization. The research concluded that the PVA hydrogels loaded with CIP and 5-NPPP nanoparticles could be an ideal and promising drug delivery system for treating S. aureus-induced skin infections.

Exploration of hemocompatibility and intratumoral accumulation of paclitaxel after loco-regional administration of thermoresponsive hydrogel composed of poloxamer and xanthan gum: An application to dose-dense chemotherapy

Although paclitaxel is a front-line chemotherapeutic agent for the treatment of metastatic breast cancer, its intravenous therapy produces deleterious adverse effects. In an attempt to address the issue, the present study aimed to develop a paclitaxel loaded thermosensitive/thermoresponsive hydrogel (PTXNp-TGel) for loco-regional administration to breast tumors to provide dose-dense chemotherapy. Poloxamer and xanthan gum were used to prepare TGel by the cold method. In vitro and in vivo performance of PTXNp-TGel was compared with TGel, pure drug loaded TGel (PTX-TGel) and marketed formulation, Taxol®. The formulated PTXNp-TGel showed acceptable gelation temperature and time (37 °C and 57 s), lower viscosity at room temperature and higher viscosity at body temperature to support sol-gel transition with increasing temperature, and sustained drug release up to 21 days. Additionally, PTXNp-TGel showed negligible hemolytic toxicity as compared to PTX-TGel and Taxol®. Intratumoral administration of PTXNp-TGel produced significantly higher antitumor activity as indicated by lowest relative tumor volume (1.50) and relative antitumor proliferation rate (27.71 %) in comparison with PTX-TGel, Taxol®, and PTXNp (p < 0.05). Finally, insignificant body weight loss during the experimental period, lack of hematotoxicity, nephrotoxicity, and hepatotoxicity imply improved therapeutic performance of the locally administrated dose-dense therapy of PTXNp-TGel as compared to Taxol®.

Progresses in Nano-Enabled Platforms for the Treatment of Vaginal Disorders

BACKGROUND

The most common vaginal disorders are within the uterus. According to the latest statistics, vaginal disorders occur in 50% to 60% of females. Although curative treatments rely on surgical therapy, still first-line treatment is a non invasive drug. Conventional therapies are available in the oral and parenteral route, leading to nonspecific targeting, which can cause dose-related side effects. Vaginal disorders are localized uterine disorders in which intrauterine delivery via the vaginal site is deemed the preferable route to mitigate clinical drug delivery limitations.

OBJECTIVE

This study emphasizes the progress of site-specific and controlled delivery of therapeutics in the treatment of vaginal disorders and systemic adverse effects as well as the therapeutic efficacy.

METHODS

Related research reports and patents associated with topics are collected, utilized, and summarized the key findings.

RESULTS

The comprehensive literature study and patents like (US 9393216 B2), (JP6672370B2), and (WO2018041268A1) indicated that nanocarriers are effective above traditional treatments and have some significant efficacy with novelty.

CONCLUSION

Nowadays, site-specific and controlled delivery of therapeutics for the treatment of vaginal disorders is essential to prevent systemic adverse effects and therapeutic efficacy would be more effective. Nanocarriers have therefore been used to bypass the problems associated with traditional delivery systems for the vaginal disorder.

Application of Sol–Gels for Treatment of Gynaecological Conditions—Physiological Perspectives and Emerging Concepts in Intravaginal Drug Delivery

Approaches for effective and sustained drug delivery to the female reproductive tract (FRT) for treating a range of gynaecological conditions remain limited. The development of versatile delivery platforms, such as soluble gels (sol–gels) coupled with applicators/devices, holds considerable therapeutic potential for gynaecological conditions. Sol–gel systems, which undergo solution-to-gel transition, triggered by physiological conditions such as changes in temperature, pH, or ion composition, offer advantages of both solution- and gel-based drug formulations. Furthermore, they have potential to be used as a suitable drug delivery vehicle for other novel drug formulations, including micro- and nano-particulate systems, enabling the delivery of drug molecules of diverse physicochemical character. We provide an anatomical and physiological perspective of the significant challenges and opportunities in attaining optimal drug delivery to the upper and lower FRT. Discussion then focuses on attributes of sol–gels that can vastly improve the treatment of gynaecological conditions. The review concludes by showcasing recent advances in vaginal formulation design, and proposes novel formulation strategies enabling the infusion of a wide range of therapeutics into sol–gels, paving the way for patient-friendly treatment regimens for acute and chronic FRT-related conditions such as bacterial/viral infection control (e.g., STDs), contraception, hormone replacement therapy (HRT), infertility, and cancer.

Nanomedicines for the topical treatment of vulvovaginal infections: Addressing the challenges of antimicrobial resistance

Recent years have, surprisingly, witnessed an increase in incidence of sexually transmitted infections (STIs). At the same time, antimicrobial therapy came under the threat of ever rising antimicrobial resistance (AMR), resulting in STIs with extremely limited therapy options. In this review, we addressed the challenges of treating vaginal infections in an era of AMR. We focused on published work regarding nanomedicine destined for localized treatment of vaginal infections. Localized therapy offers numerous advantages such as assuring high drug concentration at the infection site, limiting systemic drug exposure that can lead to faster development of AMR reduction in the systemic side effects and potentially safe therapy in pregnancy. We provided a state-of-the-art overview of nanoformulations proposed to topically treat STIs, emphasizing the challenges and advantages of each type of nanocarriers, as well as issues of potential toxicity.

Promising Polymeric Drug Carriers for Local Delivery: The Case of in situ Gels

BACKGROUND

At present, the controlled local drug delivery is a very promising approach compared to systemic administration, since it mostly targets the affected tissue. In fact, various drug carriers for local delivery have been prepared with improved therapeutic efficacy.

OBJECTIVE

in situ polymer gels are drug delivery systems that not only present liquid characteristics before their administration in body, but once they are administered, form gels due to gelation. Their gelation mechanism is due to factors such as pH alteration, temperature change, ion activation or ultraviolet irradiation. in situ gels offer various advantages compared to conventional formulations due to their ability to release drugs in a sustainable and controllable manner. Most importantly, in situ gels can be used in local drug delivery applications for various diseases.

METHODS

This review includes the basic knowledge and theory of in situ gels as well as their various applications according to their administration route.

RESULTS

Various natural, semisynthetic, and synthetic polymers can produce in situ polymeric gels. For example, natural polysaccharides such as alginic acid, chitosan, gellan gum, carrageenan etc. have been utilized as in situ gels for topical delivery. Besides the polysaccharides, poloxamers, poly(Nisopropylacrylamide), poly(ethyleneoxide)/ (lactic-co-glycolic acid), and thermosensitive liposome systems can be applied as in situ gels. In most cases, in situ polymeric gels could be applied via various administration routes such as oral, vaginal, ocular, intranasal and injectable.

CONCLUSION

To conclude, it can be revealed that in situ gels could be a promising alternative carrier for both chronic and immediate diseases.

Development and characterization of chitosan nanoparticles loaded nanofiber hybrid system for vaginal controlled release of benzydamine

Vaginal infections caused by various pathogens such as fungi, viruses and protozoa are frequently seen. Systemic and local treatments can be applied to eliminate these infections. Novel vaginal drug delivery systems can be used to provide local treatment. Vaginal drug delivery systems prevent systemic side effects and can provide long-term drug release in the vaginal area. Nanofibers and nanoparticles have a wide range of applications and can also be preferred as vaginal drug delivery systems. Benzydamine is a non-steroidal anti-inflammatory and antiseptic drug which is used for treatment of vaginal infections. The aim of this study was to compare the nanofiber and gel formulations containing lyophilized benzydamine nanoparticles with nanofiber and gel formulations containing free benzydamine, and to provide prolonged release for protection from the vaginal infections. Ionic gelation method was used for the preparation of benzydamine loaded nanoparticles. To produce benzydamine nanoparticles loaded nanofiber formulations, polyvinylpyrrolidone (PVP) solutions were prepared at 10% concentrations and mixed with nanoparticles. Hydroxypropyl methylcellulose (HPMC) was used as a gelling agent at the concentration of 1% for the vaginal gel formulation. Nanoparticles were characterized in terms of zeta potential, polydispersity index and particle size. Viscosity, surface tension and conductivity values of the polymer solutions were measured for the electrospinning. Mechanical properties, contact angle and drug loading capacity of the fibers were determined. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), fourier-transform infrared (FT-IR) spectroscopy, mucoadhesion, ex vivo permeability studies and in vitro release studies were performed for the selected formulations. Ex vivo permeability studies were performed using Franz diffusion cell method. SEM and TEM images showed that fiber diameters increased with loading of nanoparticles. DSC studies showed no interaction between excipients used in the formulation. Tensile strength and elongation at break values of the fibers increased with the loading of nanoparticles, and the contact angle values of the fibers were found to be 0°. Addition of benzydamine nanoparticles to gel and nanofiber formulations increased mucoadhesion compared to free benzydamine loading formulations. Benzydamine nanoparticle loaded gel and nanofiber formulations penetrated slower than that of free benzydamine gel and fiber formulations. The results demonstrated that benzydamine and benzydamine nanoparticle loaded fibers and gels could be a potential drug delivery system for the treatment of vaginal infections. Chitosan nanoparticle loaded nanofiber formulations are offered as an alternative controlled release vaginal formulations for vaginal infections.

Highlights in poloxamer-based drug delivery systems as strategy at local application for vaginal infections

Infectious diseases related to the vagina include diseases caused by the imbalance of the vaginal flora and by sexually transmitted infections. Some of these present themselves as a public health problem due to the lack of efficient treatment that leads to their complete cure, and others due to the growing resistance to drugs used in therapy. In this sense, new treatment strategies are desirable, with vaginal administration rout being a great choice since can bypass first-pass metabolism and decrease drug interactions and adverse effects. However, it is worth highlighting limitations related to patient's discomfort at application time. Thereby, the use of poloxamer-based drug delivery systems is desirable due its stimuli-sensitive characteristic. Therefore, the present review reports a brief overview of poloxamer properties, biological behavior and advances in poloxamer applications in controlled drug release systems for infectious diseases related to the vagina treatment and prevention.

Poloxamer Modified Chitosan Nanoparticles for Vaginal Delivery of Acyclovir

OBJECTIVE

The aim of the present study was to design a surface modified chitosan nanoparticle system for vaginal delivery of acyclovir for effective drug uptake into vaginal mucosa.

METHODS

Acyclovir-loaded chitosan nanoparticles, with and without modification by poloxamer 407, were prepared by ionic gelation method. The effects of two independent variables, chitosan to sodium tripolyphosphate mass ratio (X1) and acyclovir concentration (X2), on drug entrapment in nanoparticles were studied using 32 full factorial design. The surface response and counterplots were drawn to facilitate an understanding of the contribution of the variables and their interaction. The nanoparticles were evaluated for drug entrapment, size with zeta potential, morphological analysis by TEM, solid-state characterization by FTIR, DSC, XRD, in vitro dissolution, in vitro cell uptake using HeLa cell line and in vivo vaginal irritation test in Wistar rats.

RESULTS

Chitosan nanoparticle formulation with chitosan to sodium tripolyphosphate mass ratio of 2:1 and acyclovir concentration of 2 mg/mL resulted in the highest entrapment efficiency. The resulting nanoparticles revealed spherical morphology with a particle size of 191.2 nm. The surface modification of nanoparticles with poloxamer resulted in higher drug entrapment (74.3±1.5%), higher particle size (391.1 nm) as a result of dense surface coating, lower zeta potential and sustained drug release compared to unmodified nanoparticles. The change in the crystallinity of the drug during nanoparticle formulation was observed in DSC and XRD study. Cellular uptake of poloxamer-modified chitosan nanoparticles was found to be higher than chitosan nanoparticles in HeLa cells. Safety of nanoparticle formulations by vaginal route was evident when tested in female rats.

CONCLUSION

Conclusively, poloxamer-modified CH NP could serve as a promising and safe delivery system with enhanced cellular drug uptake.

Recent Advances in Nanosystems and Strategies for Vaginal Delivery of Antimicrobials

Vaginal infections such as bacterial vaginosis (BV), chlamydia, gonorrhea, genital herpes, candidiasis, and trichomoniasis affect millions of women each year. They are caused by an overgrowth of microorganisms, generally sexually transmitted, which in turn can be favored by alterations in the vaginal flora. Conventional treatments of these infections consist in systemic or local antimicrobial therapies. However, in the attempt to reduce adverse effects and to contrast microbial resistance and infection recurrences, many efforts have been devoted to the development of vaginal systems for the local delivery of antimicrobials. Several topical dosage forms such as aerosols, lotions, suppositories, tablets, gels, and creams have been proposed, although they are sometimes ineffective due to their poor penetration and rapid removal from the vaginal canal. For these reasons, the development of innovative drug delivery systems, able to remain in situ and release active agents for a prolonged period, is becoming more and more important. Among all, nanosystems such as liposomes, nanoparticles (NPs), and micelles with tunable surface properties, but also thermogelling nanocomposites, could be exploited to improve local drug delivery, biodistribution, retention, and uptake in vulvovaginal tissues. The aim of this review is to provide a survey of the variety of nanoplatforms developed for the vaginal delivery of antimicrobial agents. A concise summary of the most common vaginal infections and of the conventional therapies is also provided.

Inorganic and Polymeric Nanoparticles for Human Viral and Bacterial Infections Prevention and Treatment

Infectious diseases hold third place in the top 10 causes of death worldwide and were responsible for more than 6.7 million deaths in 2016. Nanomedicine is a multidisciplinary field which is based on the application of nanotechnology for medical purposes and can be defined as the use of nanomaterials for diagnosis, monitoring, control, prevention, and treatment of diseases, including infectious diseases. One of the most used nanomaterials in nanomedicine are nanoparticles, particles with a nano-scale size that show highly tunable physical and optical properties, and the capacity to a wide library of compounds. This manuscript is intended to be a comprehensive review of the available recent literature on nanoparticles used for the prevention and treatment of human infectious diseases caused by different viruses, and bacteria from a clinical point of view by basing on original articles which talk about what has been made to date and excluding commercial products, but also by highlighting what has not been still made and some clinical concepts that must be considered for futures nanoparticles-based technologies applications.

Nanotechnology in reproductive medicine: Opportunities for clinical translation

In recent years, nanotechnology has revolutionized global healthcare and has been predicted to exert a remarkable effect on clinical medicine. In this context, the clinical use of nanomaterials for cancer diagnosis, fertility preservation, and the management of infertility and other pathologies linked to pubertal development, menopause, sexually transmitted infections, and HIV (human immunodeficiency virus) has substantial promise to fill the existing lacunae in reproductive healthcare. Of late, a number of clinical trials involving the use of nanoparticles for the early detection of reproductive tract infections and cancers, targeted drug delivery, and cellular therapeutics have been conducted. However, most of these trials of nanoengineering are still at a nascent stage, and better synergy between pharmaceutics, chemistry, and cutting-edge molecular sciences is needed for effective translation of these interventions from bench to bedside. To bridge the gap between translational outcome and product development, strategic partnerships with the insight and ability to anticipate challenges, as well as an in-depth understanding of the molecular pathways involved, are highly essential. Such amalgamations would overcome the regulatory gauntlet and technical hurdles, thereby facilitating the effective clinical translation of these nano-based tools and technologies. The present review comprehensively focuses on emerging applications of nanotechnology, which holds enormous promise for improved therapeutics and early diagnosis of various human reproductive tract diseases and conditions.

Sustained-release Griffithsin nanoparticle-fiber composites against HIV-1 and HSV-2 infections

Human immunodeficiency virus (HIV-1) and herpes simplex virus 2 (HSV-2) affect hundreds of millions of people worldwide. The antiviral lectin, Griffithsin (GRFT), has been shown to be both safe and efficacious against HSV-2 and HIV-1 infections in vivo. The goal of this work was to develop a multilayered nanoparticle (NP)-electrospun fiber (EF) composite to provide sustained-release of GRFT, and to examine its safety and efficacy in a murine model of lethal HSV-2 infection. Composites were fabricated from polycaprolactone (PCL) fibers surrounding polyethylene oxide (PEO) fibers that incorporated methoxy poly(ethylene glycol)-b-poly(lactide-co-glycolide) (mPEG-PLGA) GRFT NPs. GRFT loading and release were determined via ELISA, showing that NP-EF composites achieved high GRFT loading, and provided sustained-release of GRFT for up to 90 d. The in vitro efficacy of GRFT NP-EFs was assessed using HIV-1 pseudovirus assays, demonstrating complete in vitro protection against HIV-1 infection. Additionally, sustained-release NP-EFs, administered 24 h prior to infection, prevented against a lethal dose of HSV-2 infection in a murine model. In parallel, histology and cytokine expression from murine reproductive tracts and vaginal lavages collected 24 and 72 h post-administration were similar to untreated mice, suggesting that NP-EF composites may be a promising and safe sustained-delivery platform to prevent HSV-2 infection. Future work will evaluate the ability to provide prolonged protection against multiple virus challenges, and different administration times with respect to infection.

Nanocarriers For Vaginal Drug Delivery

BACKGROUND

Vaginal drug delivery approach represents one of the imperative strategies for local and systemic delivery of drugs. The peculiar dense vascular networks, mucus permeability, and range of physiological characteristics of the vaginal cavity have been exploited for therapeutic benefit. Furthermore, the vaginal drug delivery has been curtailed due to the influence of different physiological factors like acidic pH, constant cervical secretion, microflora, cyclic changes during periods along with turnover of mucus of varying thickness.

OBJECTIVE

This review highlights advancement of nanomedicine and its prospective progress towards the clinic.

METHODS

Relevant literature reports and patents related to topics are retrieved and used.

RESULT

The extensive literature search and patent revealed that nanocarriers are efficacious over conventional treatment approaches.

CONCLUSION

Recently, nanotechnology based drug delivery approach has promised better therapeutic outcomes by providing enhanced permeation and sustained drug release activity. Different nanoplatforms based on drugs, peptides, proteins, antigens, hormones, nucleic material, and microbicides are gaining momentum for vaginal therapeutics.

Approaches in Polymeric Nanoparticles for Vaginal Drug Delivery: A Review of the State of the Art

The vagina is a region of administration with a high contact surface to obtain local or systemic effects. This anatomical area represents special interest for government health systems for different sexually transmitted infections. However, the chemical changes of the vagina, as well as its abundant mucus in continuous exchange, act as a barrier and a challenge for the development of new drugs. For these purposes, the development of new pharmaceutical forms based on nanoparticles has been shown to offer various advantages, such as bioadhesion, easy penetration of the mucosa, and controlled release, in addition to decreasing the adverse effects of conventional pharmaceutical forms. In order to obtain nanoparticles for vaginal administration, the use of polymers of natural and synthetic origin including biodegradable and non-biodegradable systems have gained great interest both in nanospheres and in nanocapsules. The main aim of this review is to provide an overview of the development of nanotechnology for vaginal drug release, analyzing the different compositions of polymeric nanoparticles, and emphasizing new trends in each of the sections presented. At the end of this review, a section analyzes the properties of the vehicles employed for the administration of nanoparticles and discusses how to take advantage of the properties that they offer. This review aims to be a reference guide for new formulators interested in the vaginal route.

The role of nanotechnology in the treatment of viral infections

Infectious diseases are the leading cause of mortality worldwide, with viruses in particular making global impact on healthcare and socioeconomic development. In addition, the rapid development of drug resistance to currently available therapies and adverse side effects due to prolonged use is a serious public health concern. The development of novel treatment strategies is therefore required. The interaction of nanostructures with microorganisms is fast-revolutionizing the biomedical field by offering advantages in both diagnostic and therapeutic applications. Nanoparticles offer unique physical properties that have associated benefits for drug delivery. These are predominantly due to the particle size (which affects bioavailability and circulation time), large surface area to volume ratio (enhanced solubility compared to larger particles), tunable surface charge of the particle with the possibility of encapsulation, and large drug payloads that can be accommodated. These properties, which are unlike bulk materials of the same compositions, make nanoparticulate drug delivery systems ideal candidates to explore in order to achieve and/or improve therapeutic effects. This review presents a broad overview of the application of nanosized materials for the treatment of common viral infections.