Solid Lipid Nanoparticles as Efficient Drug and Gene Delivery Systems: Recent Breakthroughs

Small Scale, Big Impact: Nanotechnology-Enhanced Drug Delivery for Brain Diseases

Central nervous system (CNS) diseases, ranging from brain cancers to neurodegenerative disorders like dementia and acute conditions such as strokes, have been heavily burdening healthcare and have a direct impact on patient quality of life. A significant hurdle in developing effective treatments is the presence of the blood-brain barrier (BBB), a highly selective barrier that prevents most drugs from reaching the brain. The tight junctions and adherens junctions between the endothelial cells and various receptors expressed on the cells make the BBB form a nonfenestrated and highly selective structure that is crucial for brain homeostasis but complicates drug delivery. Nanotechnology offers a novel pathway to circumvent this barrier, with nanoparticles engineered to ferry drugs across the BBB, protect drugs from degradation, and deliver medications to the designated area. After years of development, nanoparticle optimization, including sizes, shapes, surface modifications, and targeting ligands, can enable nanomaterials tailored to specific brain drug delivery settings. Moreover, smart nano drug delivery systems can respond to endogenous and exogenous stimuli that control subsequent drug release. Here, we address the importance of the BBB in brain disease treatment, summarize different delivery routes for brain drug delivery, discuss the cutting-edge nanotechnology-based strategies for brain drug delivery, and further offer valuable insights into how these innovations in nanoparticle technology could revolutionize the treatment of CNS diseases, presenting a promising avenue for noninvasive, targeted therapeutic interventions.

Anti-Toxoplasma gondii activity of rose hip oil-solid lipid nanoparticles

Toxoplasma gondii is a highly prevalent pathogen, reported from almost all geographical regions of the world. Current anti-T. gondii drugs are not effective enough in immunocompromised patients, encephalitis, chorioretinitis, and congenital toxoplasmosis. Therefore, the prescription of these drugs has been limited. Rose hip oil (RhO) is a natural plant compound, which shows antibacterial, anticancer, and anti-inflammatory activities. In the current study, the anti-T. gondii and cell toxicity effects of solid lipid nanoparticles (SLNs) loaded by RhO (RhO-SLNs) were evaluated. Emulsification sonicated-homogenization method was used to prepare SLNs. RhO-SLNs were characterized, and their anti-T. gondii and cell toxicity effects were evaluated using in vitro analyses. The particle size and the zeta potential of the nanoparticles were 152.09 nm and -15.3 mV nm, respectively. The entrapment efficiency percentage was 79.1%. In the present study, the inhibitory concentration (IC)50 against T. gondii was >1 μg/mL (p-value <.0001). The cell toxicity assay showed cytotoxicity concentration (CC)50 >10 mg/mL (p-value = .017). In addition, at least 75% of T. gondii-infected Vero cells remained alive at concentrations >10 mg/mL. The concentration of 1 mg/mL showed highest anti-Toxoplasma activity and lowest cell toxicity against the Vero cell. Our findings suggest that carrying natural plant compounds with SLNs could be considered an effective option for treatment strategies against T. gondii infections.

Emphasis on Nanostructured Lipid Carriers in the Ocular Delivery of Antibiotics

BACKGROUND

Drug distribution to the eye is still tricky because of the eye's intricate structure. Systemic delivery, as opposed to more traditional methods like eye drops and ointments, is more effective but higher doses can be harmful.

OBJECTIVE

The use of solid lipid nanoparticles (SLNPs) as a method of drug delivery has been the subject of research since the 1990s. Since SLNPs are derived from naturally occurring lipids, they pose no health risks to the user. To raise the eye's absorption of hydrophilic and lipophilic drugs, SLNs can promote corneal absorption and improve the ocular bioavailability of SLNPs.

METHODS

To address problems related to ocular drug delivery, many forms of nano formulation were developed. Some of the methods developed are, emulsification and ultra-sonication, high-speed stirring and ultra-sonication, thin layer hydration, adapted melt-emulsification, and ultrasonication techniques, hot o/w micro-emulsion techniques, etc. Results: Nanostructured lipid carriers are described in this review in terms of their ocular penetration mechanism, structural characteristic, manufacturing process, characterization, and advantages over other nanocarriers.

CONCLUSION

Recent developments in ocular formulations with nanostructured bases, such as surfacemodified attempts have been made to increase ocular bioavailability in both the anterior and posterior chambers by incorporating cationic chemicals into a wide variety of polymeric systems.

Nano-mediated strategy for targeting and treatment of non-small cell lung cancer (NSCLC)

Lung cancer is the most common type of cancer, with over 2.1 million cases diagnosed annually worldwide. It has a high incidence and mortality rate, leading to extensive research into various treatment options, including the use of nanomaterial-based carriers for drug delivery. With regard to cancer treatment, the distinct biological and physico-chemical features of nano-structures have acquired considerable impetus as drug delivery system (DDS) for delivering medication combinations or combining diagnostics and targeted therapy. This review focuses on the use of nanomedicine-based drug delivery systems in the treatment of lung cancer, including the use of lipid, polymer, and carbon-based nanomaterials for traditional therapies such as chemotherapy, radiotherapy, and phototherapy. The review also discusses the potential of stimuli-responsive nanomaterials for drug delivery in lung cancer, and the limitations and opportunities for improving the design of nano-based materials for the treatment of non-small cell lung cancer (NSCLC).

Formulation of lemongrass oil (Cymbopogon citratus)-loaded solid lipid nanoparticles: an in vitro assessment study

Cymbopogon citratus (DC) stapf. (Gramineae) is a herb known worldwide as lemongrass. The oil obtained, i.e., lemongrass oil has emerged as one among the most relevant natural oils in the pharmaceutical industry owing to its extensive pharmacological and therapeutic benefits including antioxidant, antimicrobial, antiviral and anticancer properties. However, its usage in novel formulations is constrained because of its instability and volatility. To address these concerns, the present study aims to formulate lemongrass-loaded SLN (LGSLN) using hot water titration technique. In the Smix, Tween 80 was selected as a surfactant component, while ethanol was taken as a co-surfactant. Different ratios of Smix (1:1, 1:2, 1:3, 2:1 and 3:1) were utilized to formulate LG-loaded SLN. The results indicated the fact that the LGSLN formulation (abbreviated as LGSLN1), containing lipid phase 10% w/w (i.e., LG 3.33% and SA 6.67%), Tween 80 (20% w/w), ethanol (20% w/w) and distilled water (50% w/w), revealed suitable nanometric size (142.3 ± 5.96 nm) with a high zeta potential value (- 29.12 ± 1.7 mV) and a high entrapment efficiency (77.02 ± 8.12%). A rapid drug release (71.65 ± 5.33%) was observed for LGSLN1 in a time span of 24 h. Additionally, the highest values for steady-state flux (Jss; 0.6133 ± 0.0361 mg/cm2/h), permeability coefficient (Kp; 0.4573 ± 0.0141 (cm/h) × 102) and enhancement ratio (Er; 13.50) was also conferred by LGSLN1. Based on in vitro study results, the developed SLN appeared as a potential carrier for enhanced topical administration of lemongrass oil. The observed results also indicated the fact that the phyto-cosmeceutical prospective of the nanolipidic carrier for topical administration of lemongrass oil utilizing pharmaceutically acceptable components can be explored further for widespread clinical applicability.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03726-5.

Overview of Solid Lipid Nanoparticles in Breast Cancer Therapy

Lipid nanoparticles (LNPs), composed of ionized lipids, helper lipids, and cholesterol, provide general therapeutic effects by facilitating intracellular transport and avoiding endosomal compartments. LNP-based drug delivery has great potential for the development of novel gene therapies and effective vaccines. Solid lipid nanoparticles (SLNs) are derived from physiologically acceptable lipid components and remain robust at body temperature, thereby providing high structural stability and biocompatibility. By enhancing drug delivery through blood vessels, SLNs have been used to improve the efficacy of cancer treatments. Breast cancer, the most common malignancy in women, has a declining mortality rate but remains incurable. Recently, as an anticancer drug delivery system, SLNs have been widely used in breast cancer, improving the therapeutic efficacy of drugs. In this review, we discuss the latest advances of SLNs for breast cancer treatment and their potential in clinical use.

In Vitro Prototyping of a Nano-Organogel for Thermo-Sonic Intra-Cervical Delivery of 5-Fluorouracil-Loaded Solid Lipid Nanoparticles for Cervical Cancer

Solid lipid nanoparticles (SLNs) are used extensively to achieve site-specific drug delivery with improved bioavailability and reduced toxicity. This work focused on a new approach to provide site-specific stimuli-responsive delivery of SLNs loaded within thermo-sonic nano-organogel (TNO) variants to deliver the model chemotherapeutic agent 5-FU in treating cervical cancer. Pharmaceutically stable nanospherical SLNs comprising poly-L-lactic acid (PLA), palmitic acid (PA), and polyvinyl alcohol (PVA) were prepared and incorporated into TNO variants augmented by external thermal and ultrasound stimuli for release of 5-FU in the cervix. Results revealed that rate-modulated 5-FU release was achieved from SLNs (particle size =450.9 nm; PDI =0.541; zeta potential =-23.2 mV; %DL =33%) within an organogel upon exposure to either a single (thermo-) and/or both (thermo-sonic) stimuli. 5FU was released from all TNO variants with an initial burst on day 1 followed by sustained release over 14 days. TNO 1 provided desirable release over 15 days (44.29% vs. 67.13% under single (T) or combined (TU) stimuli, respectively). Release rates were primarily influenced by the SLN:TO ratio in tandem with biodegradation and hydrodynamic influx. Biodegradation by day 7 revealed that variant TNO 1 (1:5) released 5FU (46.8%) analogous to its initial mass than the other TNO variants (i.e., ratios of 2:5 and 3:5). FT-IR spectra revealed assimilation of the system components and corroborative with the DSC and XRD analysis (i.e., in ratios of PA:PLA 1:1 and 2:1). In conclusion, the TNO variants produced may be used as a potential stimuli-responsive platform for the site-specific delivery of chemotherapeutic agents such as 5-FU to treat cervical cancer.

Cisplatin in Ovarian Cancer Treatment-Known Limitations in Therapy Force New Solutions

Cisplatin is one of the most commonly used anticancer drugs worldwide. It is mainly used in the treatment of ovarian cancer, but also used in testicular, bladder and lung cancers. The significant advantage of this drug is the multidirectional mechanism of its anticancer action, with the most important direction being damaging the DNA of cancer cells. Unfortunately, cisplatin displays a number of serious disadvantages, including toxicity to the most important organs, such as kidneys, heart, liver and inner ear. Moreover, a significant problem among patients with ovarian cancer, treated with cisplatin, is the development of numerous resistance mechanisms during therapy, including changes in the processes of cellular drug import and export, changes in the DNA damage repair mechanisms, as well as numerous changes in the processes of apoptosis and autophagy. Due to all of the mentioned problems, strategies to increase the effectiveness of cisplatin in the treatment of ovarian cancer are intensively sought. The most important strategy includes the development of less toxic cisplatin analogs. Another important direction is combination therapy, involving the simultaneous use of cisplatin with different anticancer drugs, substances derived from plants, temperature or radiotherapy. Many years of observations accompanying the presence of cisplatin in the therapy made it possible to provide a series of verifiable, statistically significant data, but also to show how, over time, with the new information and scientific discoveries, it is possible to describe and understand the therapeutic problems observed in practice, such as the acquisition of drug resistance by tumor cells or induction of changes in the tumor microenvironment. According to the authors, confronting what we knew so far with what new trends offer has a profound meaning. This paper presents information on the history of cisplatin and describes the molecular mechanisms of its action and the development of resistance by cancer cells. In addition, our goal was to highlight a number of therapeutic strategies to increase the effectiveness of cisplatin in the treatment of ovarian cancer, as well as to identify methods to eliminate problems associated with the use of cisplatin.

Solid Lipid Nanoparticles: Review of the Current Research on Encapsulation and Delivery Systems for Active and Antioxidant Compounds

Various active compounds are easily damaged, so they need protection and must be easily absorbed and targeted. This problem can be overcome by encapsulating in the form of solid lipid nanoparticles (SLNs). Initially, SLNs were widely used to encapsulate hydrophobic (non-polar) active compounds because of their matched affinity and interactions. Currently, SLNs are being widely used for the encapsulation of hydrophilic (polar) and semipolar active compounds, but there are challenges, including increasing their entrapment efficiency. This review provides information on current research on SLNs for encapsulation and delivery systems for active and antioxidant compounds, which includes various synthesis methods and applications of SLNs in various fields of utilization. SLNs can be developed starting from the selection of solid lipid matrices, emulsifiers/surfactants, types of active compounds or antioxidants, synthesis methods, and their applications or utilization. The type of lipid used determines crystal formation, control of active compound release, and encapsulation efficiency. Various methods can be used in the SLN fabrication of active compounds and hydrophilic/hydrophobic antioxidants, which have advantages and disadvantages. Fabrication design, which includes the selection of lipid matrices, surfactants, and fabrication methods, determines the characteristics of SLNs. High-shear homogenization combined with ultrasonication is the recommended method and has been widely used because of the ease of preparation and good results. Appropriate fabrication design can produce SLNs with stable active compounds and antioxidants that become suitable encapsulation systems for various applications or uses.

Delivery Systems for Mitochondrial Gene Therapy: A Review

Mitochondria are membrane-bound cellular organelles of high relevance responsible for the chemical energy production used in most of the biochemical reactions of cells. Mitochondria have their own genome, the mitochondrial DNA (mtDNA). Inherited solely from the mother, this genome is quite susceptible to mutations, mainly due to the absence of an effective repair system. Mutations in mtDNA are associated with endocrine, metabolic, neurodegenerative diseases, and even cancer. Currently, therapeutic approaches are based on the administration of a set of drugs to alleviate the symptoms of patients suffering from mitochondrial pathologies. Mitochondrial gene therapy emerges as a promising strategy as it deeply focuses on the cause of mitochondrial disorder. The development of suitable mtDNA-based delivery systems to target and transfect mammalian mitochondria represents an exciting field of research, leading to progress in the challenging task of restoring mitochondria's normal function. This review gathers relevant knowledge on the composition, targeting performance, or release profile of such nanosystems, offering researchers valuable conceptual approaches to follow in their quest for the most suitable vectors to turn mitochondrial gene therapy clinically feasible. Future studies should consider the optimization of mitochondrial genes' encapsulation, targeting ability, and transfection to mitochondria. Expectedly, this effort will bring bright results, contributing to important hallmarks in mitochondrial gene therapy.

Recent advances in multifunctional dendrimer-based nanoprobes for breast cancer theranostics

Breast cancer (BC) undoubtedly is one of the most common type of cancers amongst women, which causes about 5 million deaths annually. The treatments and diagnostic therapy choices currently available for Breast Cancer is very much limited . Advancements in novel nanocarrier could be a promising strategy for diagnosis and treatments of this deadly disease. Dendrimer nanoformulation could be functionalized and explored for efficient targeting of overexpressed receptors on Breast Cancer cells to achieve targeted drug delivery, for diagnostics and to overcome the resistance of the cells towards particular chemotherapeutic. Additionally, the dendrimer have shown promising potential in the improvement of therapeutic value for Breast Cancer therapy by achieving synergistic co-delivery of chemotherapeutics and genetic materials for multidirectional treatment. In this review, we have highlighted the application of dendrimer as novel multifunctional nanoplatforms for the treatment and diagnosis of Breast Cancer.

Mechanisms and challenges of nanocarriers as non-viral vectors of therapeutic genes for enhanced pulmonary delivery

With the rapid development of biopharmaceuticals and the outbreak of COVID-19, the world has ushered in a frenzy to develop gene therapy. Therefore, therapeutic genes have received enormous attention. However, due to the extreme instability and low intracellular gene expression of naked genes, specific vectors are required. Viral vectors are widely used attributed to their high transfection efficiency. However, due to the safety concerns of viral vectors, nanotechnology-based non-viral vectors have attracted extensive investigation. Still, issues of low transfection efficiency and poor tissue targeting of non-viral vectors need to be addressed. Especially, pulmonary gene delivery has obvious advantages for the treatment of inherited lung diseases, lung cancer, and viral pneumonia, which can not only enhance lung targeting and but also reduce enzymatic degradation. For systemic diseases therapy, pulmonary gene delivery can enhance vaccine efficacy via inducing not only cellular, humoral immunity but also mucosal immunity. This review provides a comprehensive overview of nanocarriers as non-viral vectors of therapeutic genes for enhanced pulmonary delivery. First of all, the characteristics and therapeutic mechanism of DNA, mRNA, and siRNA are provided. Thereafter, the advantages and challenges of pulmonary gene delivery in exerting local and systemic effects are discussed. Then, the inhalation dosage forms for nanoparticle-based drug delivery systems are introduced. Moreover, a series of materials used as nanocarriers for pulmonary gene delivery are presented, and the endosomal escape mechanisms of nanocarriers based on different materials are explored. The application of various non-viral vectors for pulmonary gene delivery are summarized in detail, with the perspectives of nano-vectors for pulmonary gene delivery.

Approaches for designing and delivering solid lipid nanoparticles of distinct antitubercular drugs

Tuberculosis (TB) is still the biggest infectious disease among adults globally, which effects the social and biological lives of patients as well as the economic liability of healthcare systems. Current treatment regime has challenges with drug resistant (MDR/XDR) strains and the failure of standard therapeutic interventions against these TB strains. In the recent years, several nanocarrier-based drug delivery systems developed (including lipid-based) with anti-tuberculosis drugs via targeted delivery to improve the therapeutic outcomes. In this review, we attempt to summarize on the composition of the reported solid lipid-based particles (SLNPs), their various production methodologies, and properties of the delivery system, and their influence on cellular and pharmacokinetic aspects are also discussed. Besides, we have highlighted anti-TB drugs delivering via lipid-based systems have shown promising outcomes, however clinical translation of such systems is still under investigation. Based on recent advancements and reports, it is recommended that future efforts be made to accelerate the translational development of lipid-based nanocarriers to improve TB treatment.

Verapamil hydrochloride loaded solid lipid nanoparticles: Preparation, optimization, characterisation, and assessment of cardioprotective effect in experimental model of myocardial infarcted rats

Verapamil, a calcium channel blocker has poor bioavailability (20-30%) owing to extensive hepatic first-pass metabolism. Hence, the major objective of this research was to improve the oral bioavailability of Verapamil by Solid Lipid Nanoparticles (V-SLNs) using high shear homogenization and ultrasonication technology. A 3² factorial design was employed to statistically optimize the formulation to get minimum particle size with maximum entrapment efficiency. The average particle size was 218 nm and the entrapment efficiency was 80.32%. The V-SLN formulation exhibited biphasic behavior with a rapid release at first, then a steady release (75-80%) up to 24 h following the Korsmeyer Peppas release model. In the Isoproterenol induced myocardial necrosis model, oral administration of V-SLNs positively modulated almost all the studied hemodynamic parameters such as left ventricular end-diastolic pressure, cardiac injury markers, and tissue architecture. The cardioprotective effect was also confirmed with histopathological studies. When compared with free drugs, in-vivo pharmacokinetic studies demonstrated a rise in t_1/2, AUC_0-∞, and Cmax, indicating that bioavailability has improved. These encouraging results demonstrate the promising potential of developed V-SLNs for oral delivery and thereby improve the therapeutic outcome.

Nanotechnology Advances in the Detection and Treatment of Cancer: An Overview

Over the last few years, progress has been made across the nanomedicine landscape, in particular, the invention of contemporary nanostructures for cancer diagnosis and overcoming complexities in the clinical treatment of cancerous tissues. Thanks to their small diameter and large surface-to-volume proportions, nanomaterials have special physicochemical properties that empower them to bind, absorb and transport high-efficiency substances, such as small molecular drugs, DNA, proteins, RNAs, and probes. They also have excellent durability, high carrier potential, the ability to integrate both hydrophobic and hydrophilic compounds, and compatibility with various transport routes, making them especially appealing over a wide range of oncology fields. This is also due to their configurable scale, structure, and surface properties. This review paper discusses how nanostructures can function as therapeutic vectors to enhance the therapeutic value of molecules; how nanomaterials can be used as medicinal products in gene therapy, photodynamics, and thermal treatment; and finally, the application of nanomaterials in the form of molecular imaging agents to diagnose and map tumor growth.

Nanomedicine for the Delivery of RNA in Cancer

The complexity, and the diversity of the different types of cancers allied to the tendency to form metastasis make treatment efficiency so tricky and often impossible due to the advanced stage of the disease in the diagnosis. In recent years, due to tremendous scientific breakthroughs, we have witnessed exponential growth in the elucidation of mechanisms that underlie carcinogenesis and metastasis. The development of more selective therapies made it possible to improve cancer treatment. Although interdisciplinary research leads to encouraging results, scientists still have a long exploration journey. RNA technology represents a promise as a therapeutic intervention for targeted gene silencing in cancer, and there are already some RNA-based formulations in clinical trials. However, the use of RNA as a therapeutic tool presents severe limitations, mainly related to its low stability and poor cellular uptake. Thus, the use of nanomedicine employing nanoparticles to encapsulate RNA may represent a suitable platform to address the major challenges hampering its therapeutic application. In this review, we have revisited the potential of RNA and RNA-associated therapies to fight cancer, also providing, as support, a general overview of nanoplatforms for RNA delivery.

Nanostructured lipid carriers: a promising drug carrier for targeting brain tumours

Background

In recent years, the field of nanotechnology and nanomedicine has transformed the pharmaceutical industry with the development of novel drug delivery systems that overcome the shortcomings of traditional drug delivery systems. Nanostructured lipid carriers (NLCs), also known as the second-generation lipid nanocarriers, are one such efficient and targeted drug delivery system that has gained immense attention all across due to their myriad advantages and applications. Scientific advancements have revolutionized our health system, but still, brain diseases like brain tumour have remained formidable owing to poor prognosis and the challenging drug delivery to the brain tissue. In this review, we highlighted the application and potential of NLCs in brain-specific delivery of chemotherapeutic agents.

Main body

NLCs are lipid-based formulations with a solid matrix at room temperature and offer advantages like enhanced stability, low toxicity, increased shelf life, improved drug loading capacity, and biocompatibility over other conventional lipid-based nanocarriers such as nanoemulsions and solid lipid nanoparticles. This review meticulously articulates the structure, classification, components, and various methods of preparation exemplified with various research studies along with their advantages and disadvantages. The concept of drug loading and release has been discussed followed by a brief about stability and strategies to improve stability of NLCs. The review also summarizes various in vitro and in vivo research studies on NLCs encapsulated with cytotoxic drugs and their potential application in brain-specific drug delivery.

Conclusion

NLCs are employed as an important carrier for the delivery of food, cosmetics, and medicines and recently have been used in brain targeting, cancer, and gene therapy. However, in this review, the applications and importance of NLCs in targeting brain tumour have been discussed in detail stating examples of various research studies conducted in recent years. In addition, to shed light on the promising role of NLCs, the current clinical status of NLCs has also been summarized.

Graphical Abstract

Comprehensive comparison of theranostic nanoparticles in breast cancer

Breast cancer is the most frequently happening cancer and the most typical cancer death among females. Despite the crucial progress in breast cancer therapy by using Chemotherapeutic agents, most anti-tumor drugs are insufficient to destroy exactly the breast cancer cells. The noble method of drug delivery using nanoparticles presents a great promise in treating breast cancer most sufficiently and with the least harm to the patient. Nanoparticles, with their spectacular characteristics, help overcome problems of this kind. Unique features of nanoparticles such as biocompatibility, bioavailability, biodegradability, sustained release, and, most importantly, site-specific targeting enables the Chemotherapeutic agents loaded in nanocarriers to differentiate between healthy tissue and cancer cells, leading to low toxicity and fewer side effects. This review focuses on evaluating and comprehending nanoparticles utilized in breast cancer treatment, including the most recent data related to the drugs they can carry. Also, this review covers all information related to each nanocarrier, such as their significant characteristics, subtypes, advantages, disadvantages, and chemical modification methods with recently published studies. This article discusses over 21 nanoparticles used in breast cancer treatment with possible chemical ligands such as monoclonal antibodies and chemotherapeutic agents binding to these carriers. These different nanoparticles and the unique features of each nanocarrier give the researchers all the data and insight to develop and use the brand-new drug delivery system.

A Review on Polymer and Lipid-Based Nanocarriers and Its Application to Nano-Pharmaceutical and Food-Based Systems

Recently, owing to well-controlled release, enhanced distribution and increased permeability, nanocarriers used for alternative drug and food-delivery strategies have received increasingly attentions. Nanocarriers have attracted a large amount of interest as potential carriers of various bioactive molecules for multiple applications. Drug and food-based delivery via polymeric-based nanocarriers and lipid-based nanocarriers has been widely investigated. Nanocarriers, especially liposomes, are more and more widely used in the area of novel nano-pharmaceutical or food-based design. Herein, we aimed to discuss the recent advancement of different surface-engineered nanocarriers type, along with cutting-edge applications for food and nanomedicine and highlight the alternative of phytochemical as nanocarrier. Additionally, safety concern of nanocarriers was also highlighted.

Decapeptide Modified Doxorubicin Loaded Solid Lipid Nanoparticles as Targeted Drug Delivery System against Prostate Cancer

Growing instances of prostate cancer with poor prognosis have become a challenging task in cancer therapy. Luteinizing-hormone-releasing-hormone (LHRH) receptors are overexpressed in prostate cancer cells. Polyethylene glycol (PEG) conjugated lipids exhibit superiority in terms of retention/circulation in biological systems. PEGylated dipalmitoylphosphatedylethanolamine (DPPE-PEG), covalently linked with 6-hydrazinopyridine-3-carboxylic-acid, was conjugated with new LHRH-receptor positive peptide analog (DPPE-PEG-HYNIC-d-Glu-His-Trp-Ser-Tyr-d-Asn-Leu-d-Gln-Pro-Gly-NH₂). Surface modified doxorubicin (DOX) loaded solid lipid nanoparticle (SLN) was prepared using soylecithin, stearic acid and Poloxamer-188 by solvent emulsification/evaporation method for targeted delivery of DOX into prostate cancer cells. SLN, DOX loaded SLN (DSLN) and surface modified DSLN (M-DSLN) were characterized by means of their size, zeta potential, morphology, storage time, drug payload, and subsequent release kinetics studies. Homogeneity of surface morphology, upon modification of SLN, was revealed from the dynamic light scattering, atomic force microscopy, and scanning electron microscopic studies. Homogeneous adsolubilization of DOX throughout the hydrophobic moiety of SLN was established by the differential scanning calorimetric studies. Release of DOX were sustained in DSLN and M-DSLN. Cellular uptake and in vitro activities of formulations against LHRH positive PC3/SKBR3 cancer cell lines revealed higher cellular internalization, cytotoxicity that followed the sequence DOX < DSLN < M-DSLN. Dye staining and flow cytometry studies revealed higher apoptosis in cancer cells. Such receptor specific drug delivery systems are considered to have substantial potential in prostate cancer therapy.

Skin cancer therapeutics: nano-drug delivery vectors—present and beyond

Background

Skin cancers are among the widely prevalent forms of cancer worldwide. The increasing industrialization and accompanied environmental changes have further worsened the skin cancer statistics. The stern topical barrier although difficult to breach is a little compromised in pathologies like skin cancer. The therapeutic management of skin cancers has moved beyond chemotherapy and surgery.

Main body of the abstract

The quest for a magic bullet still prevails, but topical drug delivery has emerged as a perfect modality for localized self-application with minimal systemic ingress for the management of skin cancers. Advances in topical drug delivery as evidenced by the exploration of nanocarriers and newer technologies like microneedle-assisted/mediated therapeutics have revolutionized the paradigms of topical treatment. The engineered nanovectors have not only been given the liberty to experiment with a wide-array of drug carriers with very distinguishing characteristics but also endowed them with target specificity. The biologicals like nucleic acid-based approaches or skin penetrating peptide vectors are another promising area of skin cancer therapeutics which has demonstrated potential in research studies. In this review, a panoramic view is presented on the etiology, therapeutic options, and emerging drug delivery modalities for skin cancer.

Short conclusion

Nanocarriers have presented innumerable opportunities for interventions in skin cancer therapeutics. Challenge persists for the bench to bedside translation of these highly potential upcoming therapeutic strategies.

Graphic abstract

Structured edible lipid-based particle systems for oral drug-delivery

Oral administration is the most popular and patient-compliant route for drug delivery, though it raises great challenges due to the involvement of the gastro-intestine (GI) system and the drug bioavailability. Drug bioavailability is directly related to its ability to dissolve, transport and/or absorb through the physiological environment. A great number of drugs are characterized with low water solubility due to their hydrophobic nature, thus limiting their oral bioavailability and clinical use. Therefore, new strategies aiming to provide a protective shell through the GI system and improve drug solubility and permeability in the intestine were developed to overcome this limitation. Lipid-based systems have been proposed as good candidates for such a task owing to their hydrophobic nature which allows high drug loading, drug micellization ability during intestinal digestion due to the lipid content, and the vehicle physical protective environment. The use of edible lipids with high biocompatibility paves the bench-to-bedside translation. Four main types of structured lipid-based drug delivery systems differing in the physical state of the lipid phase have been described in the literature, namely emulsions, solid lipid nanoparticles, nanostructured lipid carriers, and oleogel-based particles. The current review provides a comprehensive overview of the different structured edible lipid-based oral delivery systems investigated up to date and emphasizes the contribution of each system component to the delivery performance, and the oral delivery path of lipids.

Preclinical Assessment of Ursolic Acid Loaded into Nanostructured Lipid Carriers in Experimental Visceral Leishmaniasis

Ursolic acid, a triterpene produced by plants, displayed leishmanicidal activity in vitro and in vivo; however, the low solubility of this triterpene limits its efficacy. To increase the activity of ursolic acid (UA), this triterpene was entrapped in nanostructured lipid carriers (UA-NLC), physical-chemical parameters were estimated, the toxicity was assayed in healthy golden hamsters, and the efficacy of UA-NLC was studied in experimental visceral leishmanisis. UA-NLC exhibited a spherical shape with a smooth surface with a size of 266 nm. UA-NLC displayed low polydispersity (PDI = 0.18) and good colloidal stability (-29.26 mV). Hamsters treated with UA-NLC did not present morphological changes in visceral organs, and the levels of AST, ALT, urea and creatinine were normal. Animals infected with Leishmania (Leishmania) infantum and treated with UA-NLC showed lower parasitism than the infected controls, animals treated with UA or Amphotericin B (AmB). The therapeutic activity of UA-NLC was associated with the increase in a protective immune response, and it was associated with a high degree of spleen and liver preservation, and the normalization of hepatic and renal functions. These data indicate that the use of lipid nanoparticles as UA carriers can be an interesting strategy for the treatment of leishmaniasis.

Nanocarriers-Mediated Drug Delivery Systems for Anticancer Agents: An Overview and Perspectives

Nanotechnology has been actively integrated as drug carriers over the last few years to treat various cancers. The main hurdle in the clinical management of cancer is the development of multidrug resistance against chemotherapeutic agents. To overcome the limitations of chemotherapy, the researchers have been developing technological advances for significant progress in the oncotherapy by enabling the delivery of chemotherapeutic agents at increased drug content levels to the targeted spots. Several nano-drug delivery systems designed for tumor-targeting are evaluated in preclinical and clinical trials and showed promising outcomes in cancerous tumors' clinical management. This review describes nanocarrier's importance in managing different types of cancers and emphasizing nanocarriers for drug delivery and cancer nanotherapeutics. It also highlights the recent advances in nanocarriers-based delivery systems, including polymeric nanocarriers, micelles, nanotubes, dendrimers, magnetic nanoparticles, solid lipid nanoparticles, and quantum dots (QDs). The nanocarrier-based composites are discussed in terms of their structure, characteristics, and therapeutic applications in oncology. To conclude, the challenges and future exploration opportunities of nanocarriers in chemotherapeutics are also presented.

Flavonoid-Based Nanomedicines in Alzheimer's Disease Therapeutics: Promises Made, a Long Way To Go

Alzheimer's disease (AD) is characterized by the continuous decline of the cognitive abilities manifested due to the accumulation of large aggregates of amyloid-beta 42 (Aβ42), the formation of neurofibrillary tangles of hyper-phosphorylated forms of microtubule-associated tau protein, which may lead to many alterations at the cellular and systemic level. The current therapeutic strategies primarily focus on alleviating pathological symptoms rather than providing a possible cure. AD is one of the highly studied but least understood neurological problems and remains an unresolved condition of human brain degeneration. Over the years, multiple naturally derived small molecules, including plant products, microbial isolates, and some metabolic byproducts, have been projected as supplements reducing the risk or possible treatment of the disease. However, unfortunately, none has met the expected success. One major challenge for most medications is their ability to cross the blood-brain barrier (BBB). In past decades, nanotechnology-based interventions have offered an alternative platform to address the problem of the successful delivery of the drugs to the specific targets. Interestingly, the exciting interface of natural products and nanomedicine is delivering promising results in AD treatment. The potential applications of flavonoids, the plant-derived compounds best known for their antioxidant activities, and their amalgamation with nanomedicinal approaches may lead to highly effective therapeutic strategies for treating well-known neurodegenerative diseases. In the present review, we explore the possibilities and recent developments on an exciting combination of flavonoids and nanoparticles in AD.

Gemcitabine Peptide-Based Conjugates and Their Application in Targeted Tumor Therapy

A major obstacle in tumor treatment is associated with the poor penetration of a therapeutic agent into the tumor tissue and with their adverse influence on healthy cells, which limits the dose of drug that can be safely administered to cancer patients. Gemcitabine is an anticancer drug used to treat a wide range of solid tumors and is a first-line treatment for pancreatic cancer. The effect of gemcitabine is significantly weakened by its rapid plasma degradation. In addition, the systemic toxicity and drug resistance significantly reduce its chemotherapeutic efficacy. Up to now, many approaches have been made to improve the therapeutic index of gemcitabine. One of the recently developed approaches to improve conventional chemotherapy is based on the direct targeting of chemotherapeutics to cancer cells using the drug-peptide conjugates. In this work, we summarize recently published gemcitabine peptide-based conjugates and their efficacy in anticancer therapy.

A Review on Ocular Novel Drug Delivery Systems of Antifungal Drugs: Functional Evaluation and Comparison of Conventional and Novel Dosage Forms

Ocular fungal infections affect more than one million people annually worldwide. They can lead to impaired vision or even complete blindness, so they should be treated immediately to prevent such consequences. Although topical administration has always been the most common route of ocular drug delivery owing to high patient acceptance, reduced side effects, and the possibility of self-administration, its limited ocular bioavailability poses a major challenge. As a result, attention has recently been drawn to the design and development of novel drug delivery systems (NDDS) that can overcome the challenges of conventional dosage forms. This research is the first to review and classify the studies which have designed and developed topical ocular NDDS with the aim to compare the performance and antifungal activity of these novel systems with conventional forms. According to the results, all studies seemed to confirm the superiority of NDDS over conventional forms in cases of released and permeated drug and antifungal activity. The NDDS were used specifically to improve ocular delivery by slowing down the release rate, increasing drug permeation, and subsequently increasing the antifungal effects of the active pharmaceutical ingredients. Hence, further studies on NDDS may aid the optimization of ocular drug delivery of antifungal drugs.

FbD directed fabrication and investigation of luliconazole based SLN gel for the amelioration of candidal vulvovaginitis: a 2 T (thermosensitive & transvaginal) approach

Candidal vulvovaginitis (CVV), is the second most leading vaginal infection (global prevalence > 75%), caused due to excessive growth of Candida spp., predominantly Candida albicans (>95% cases). The current treatment regimens for CVV are marred with the challenges of fungal resistance & infection recurrence, subsequently leading to the compromised therapeutic efficacy of anti-fungal drugs, prolonged treatment and low patient compliance. The core of the present research was the fabrication & investigation of 2 T-SLN (solid lipid nanoparticles) gel carrying luliconazole for the amelioration of CVV. '2T' symbolizes transvaginal & thermosensitive attributes of the present formulation. SLNs were prepared by a modified melt emulsification-ultra sonication method using a combination of solid lipids (Gelucire 50/13 & Precirol ATO 5), surfactant (Tween 80) and co-surfactant (Kolliphor). Formulation by design (FbD) approach was adopted to obtain appropriately screened and tailored SLNs. The optimized SLNs yielded a particle size, polydispersity index & entrapment efficiency of 62.18 nm, 0.263 & 81.5% respectively. To formulate the 2 T-gel, the final SLNs were loaded into Carbopol 971P-NF and Triethanolamine based gel. The 2 T-SLN gel was found to be easily spreadable and homogenous with mean extrudability (15 ± 0.4 g/cm²), viscosity (696.42 ± 2.34 Pa·s) and %drug content (93.24 ± 0.73%) values.. The pH of the prepared 2 T-SLN gel (4.5 ± 0.5) was in concordance with the vaginal pH (normal conditions). For in-vitro characterization of an optimized 2 T-SLN gel the release kinetics & anticandidal activity were assessed which offers a %cumulative drug release of 62 ± 0.5% in 72 h and 37.3 ± 1.5 mm zone of inhibition in 48 h. The visual appearance & dimensions were determined using fluorescent microscopy (spherical shape) & transmission electron microscopy (90-120 nm) respectively. The optimized 2 T-SLN gel showcases a skin-friendly profile with no significant signs of erythema and oedema and was found to be stable at room temperature for 2 months without any visual non-uniformity/cracking/breaking. In conclusion, the current research serves a new therapeutic perspective in assessing the activity of luliconazole for vaginal drug delivery using a 2 T-SLN gel system.

Therapeutic Nanoparticles and Their Targeted Delivery Applications

Nanotechnology offers many advantages in various fields of science. In this regard, nanoparticles are the essential building blocks of nanotechnology. Recent advances in nanotechnology have proven that nanoparticles acquire a great potential in medical applications. Formation of stable interactions with ligands, variability in size and shape, high carrier capacity, and convenience of binding of both hydrophilic and hydrophobic substances make nanoparticles favorable platforms for the target-specific and controlled delivery of micro- and macromolecules in disease therapy. Nanoparticles combined with the therapeutic agents overcome problems associated with conventional therapy; however, some issues like side effects and toxicity are still debated and should be well concerned before their utilization in biological systems. It is therefore important to understand the specific properties of therapeutic nanoparticles and their delivery strategies. Here, we provide an overview on the unique features of nanoparticles in the biological systems. We emphasize on the type of clinically used nanoparticles and their specificity for therapeutic applications, as well as on their current delivery strategies for specific diseases such as cancer, infectious, autoimmune, cardiovascular, neurodegenerative, ocular, and pulmonary diseases. Understanding of the characteristics of nanoparticles and their interactions with the biological environment will enable us to establish novel strategies for the treatment, prevention, and diagnosis in many diseases, particularly untreatable ones.

Investigation on Secondary Structure Alterations of Protein Drugs as an Indicator of Their Biological Activity Upon Thermal Exposure

Protein drugs are important therapeutic agents however; they may degrade during formulation processing. The objective of this study was to investigate the correlation between secondary structure alterations and the retentions of biological activity of protein upon the application of thermal stress. Catalase, horseradish peroxidase and α- chymotrypsin were employed as model proteins. Each protein was heated in a solid and solution state at a temperature of 70 °C for 1 h. Attenuated total reflectance Fourier transform infrared spectroscopy, size-exclusion chromatography and biological activity assay were performed. Results showed that heat-exposure of protein solids at 70 °C caused minimum changes in secondary structure and biological activity was almost retained. However, thermal exposure of protein aqueous solution induced significant changes in the secondary structure indicated by area overlap values and caused considerable reduction in the biological activity. The changes in secondary structures were found to be in full alignment with the loss of biological activity for both protein solids as well as aqueous solutions. Catalase lost entire biological activity upon heating in the solution state. In conclusion, the findings of the present study indicate a direct correlation between protein secondary structure alterations and the retention of biological activity which can be taken into account during the development and delivery of protein drugs formulations.

Nano-antimicrobials: A New Paradigm for Combating Mycobacterial Resistance

BACKGROUND

Mycobacterium group contains several pathogenic bacteria including M. tuberculosis where the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) is alarming for human and animal health around the world. The condition has further aggravated due to the speed of discovery of the newer drugs has been outpaced by the rate of resistance developed in microorganisms, thus requiring alternative combat strategies. For this purpose, nano-antimicrobials have emerged as a potential option.

OBJECTIVE

The current review is focused on providing a detailed account of nanocarriers like liposome, micelles, dendrimers, solid lipid NPs, niosomes, polymeric nanoparticles, nano-suspensions, nano-emulsion, mesoporous silica and alginate-based drug delivery systems along with the recent updates on developments regarding nanoparticle-based therapeutics, vaccines and diagnostic methods developed or under pipeline with their potential benefits and limitations to combat mycobacterial diseases for their successful eradication from the world in future.

RESULTS

Distinct morphology and the underlying mechanism of pathogenesis and resistance development in this group of organisms urge improved and novel methods for the early and efficient diagnosis, treatment and vaccination to eradicate the disease. Recent developments in nanotechnology have the potential to meet both the aspects: nano-materials are proven components of several efficient targeted drug delivery systems and the typical physicochemical properties of several nano-formulations have shown to possess distinct bacteriocidal properties. Along with the therapeutic aspects, nano-vaccines and theranostic applications of nano-formulations have grown in popularity in recent times as an effective alternative means to combat different microbial superbugs.

CONCLUSION

Nanomedicine holds a bright prospect to perform a key role in global tuberculosis elimination program.

Development and Characterization of Nanoliposomal Hydroxyurea Against BT-474 Breast Cancer Cells

Purpose: Hydroxyurea (HU) is a well-known chemotherapy drug with several side effects which limit its clinical application. This study was conducted to improve its therapeutic efficiency against breast cancer using liposomes as FDA-approved drug carriers.

Methods: PEGylated nanoliposomes-containing HU (NL-HU) were made via a thin-film hydration method, and assessed in terms of zeta potential, size, morphology, release, stability, cellular uptake, and cytotoxicity. The particle size and zeta potential of NL-HU were specified by zeta-sizer. The drug release from liposomes was assessed by dialysis diffusion method. Cellular uptake was evaluated by flow cytometry. The cytotoxicity was designated by methyl thiazolyl diphenyl-tetrazolium bromide (MTT) test.

Results: The size and zeta value of NL-HU were gotten as 85 nm and -27 mV, respectively. NL-HU were spherical.NL-HU vesicles were detected to be stable for two months. The slow drug release and Weibull kinetic model were obtained. Liposomes considerably enhanced the uptake of HU into BT-474 human breast cancer cells. The cytotoxicity of NL-HU on BT-474 cells was found to be significantly more than that of free HU.

Conclusion: The results confirmed these PEGylated nanoliposomes containing drug are potentially suitable against in vitro model of breast cancer.

Targeted delivery and apoptosis induction of trans-resveratrol-ferulic acid loaded chitosan coated folic acid conjugate solid lipid nanoparticles in colon cancer cells

The present study is aimed to study and to evaluate the colon cancer targeting efficacy of chitosan-coated-trans-resveratrol (RSV) and ferulic acid (FER) loaded SLNs (solid lipid nanoparticles) that conjugated with folic acid (FA) (C-RSV-FER-FA-SLNs) in suitable models (in vitro). The FA conjugation is performed using co-encapsulation method of stearic acid. Similarly, the prepared SLNs are exhibited better stability even under acidic conditions to exhibit their potentials to use as drug delivery system. Further, the optimized formulations (SLNs) are tested for physiochemical characterizations, which include FTIR, XRD, ¹HNMR, particle size, zeta potential, and drug release. In vitro anti-cancer studies using HT-29 cells including, fluorescence staining, flow cytometry, and western blot analysis revealed that the C-RSV-FER-FA-SLNs effectively involved and increased cytotoxicity in cancer cells that leads to induction of apoptosis as compared to free RSV-FER. Thus, it is reported that, the good stability under acidic conditions of this C-RSV-FER-FA-SLNs may serve as a promising candidate for novel nanodrug formulations in cancer therapy.

Nanoformulations for glioblastoma multiforme: a new hope for treatment

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults, associated with a high mortality rate and a survival of between 12 and 15 months after diagnosis. Due to current treatment limitations involving surgery, radiotherapy and chemotherapy with temozolamide, there is a high rate of treatment failure and recurrence. To try to overcome these limitations nanotechnology has emerged as a novel alternative. Lipid, polymeric, silica and magnetic nanoparticles, among others, are being developed to improve GBM treatment and diagnosis. These nanoformulations have many advantages, including lower toxicity, biocompatibility and the ability to be directed toward the tumor. This article reviews the progress that have been made and the large variety of nanoparticles currently under study for GBM.

The impact of topical phenytoin loaded nanostructured lipid carriers in diabetic foot ulceration

OBJECTIVE

The aim of this study is to develop, and characterize nanostructured lipid carriers (NLCs) of phenytoin (PHT) in order to improve its entrapment efficiency and sustained release to improve the healing process.

METHODS

Twenty-seven patients with neuropathic diabetic foot ulceration (DFU) were enrolled in this study. Patients were comparable regarding size, grading of ulcer and control of diabetes with no major deformity. All patients were managed by weekly sharp debridement if indicated and offloaded with cast shoes. They were equally divided into three groups: PHT-NLC-hydrogel (0.5%w/v), phenytoin hydrogel (0.5%w/v) and blank hydrogel groups. Changes in wound area were monitored over 2 months.

RESULTS

Baseline wound area of PHT-NLC, PHT and blank hydrogels were 5.50 ± 3.66, 3.94 ± 1.86 and 5.36 ± 2.14 cm², respectively. Ulcers treated with PHT-NLC hydrogel showed smaller wound area compared to control groups (ρ < 0.05). The overall reduction in ulcer size were 95.82 ± 2.22% for PHT-NLC-hydrogel in comparison to 47.10 ± 4.23% and -34.91 ± 28.33% for PHT and blank-hydrogel (ρ < 0.001), respectively.

CONCLUSION

PHT-NLC hydrogel speeds up the healing process of the DFU without adverse effects when compared to the positive and negative control hydrogels. Moreover, the study can open a window for topical application of NLCs loaded with PHT in the treatment of numerous dermatological disorders that resist conventional treatment.

KEY MESSAGE

The delivery of drug molecules and their localization into the skin is the main purpose of the topical dosage forms. In this manuscript, the impact of topical phenytoin loaded nanostructured lipid carrier in improving wound healing in patients with neuropathic diabetic foot ulceration was investigated. Phenytoin loaded nanostructured lipid carrier dressing was found to be more effective than phenytoin hydrogel at the same concentration in healing of neuropathic diabetic foot ulcer.

Targeted Drug Delivery in Lipid-like Nanocages and Extracellular Vesicles

The possibility of targeted drug delivery to a specific tissue, organ, or cell has opened new promising avenues in treatment development. The technology of targeted delivery aims to create multifunctional carriers that are capable of long circulation in the patient's organism and possess low toxicity at the same time. The surface of modern synthetic carriers has high structural similarity to the cell membrane, which, when combined with additional modifications, also promotes the transfer of biological properties in order to penetrate physiological barriers effectively. Along with artificial nanocages, further efforts have recently been devoted to research into extracellular vesicles that could serve as natural drug delivery vehicles. This review provides a detailed description of targeted delivery systems that employ lipid and lipid-like nanocages, as well as extracellular vesicles with a high level of biocompatibility, highlighting genetically encoded drug delivery vehicles.

Ethambutol-Loaded Solid Lipid Nanoparticles as Dry Powder Inhalable Formulation for Tuberculosis Therapy

Ethambutol hydrocloride (EMB) is an anti-tuberculosis drug, which is commonly used as a protection agent against of unrecognized resistance to other drugs employed to treat this disease. Since oral form of EMB has some side effects and cellular toxicity, direct administration of EMB into lungs seems to be an attractive and reasonable option in order to overcome these side effects. Our main goal in this study was assessment of pulmonary administration through dry powder inhaler (DPI) using EMB-loaded solid lipid nanoparticles (SLNs). We prepared EMB-loaded SLNs using two techniques (hot homogenization and ultrasonication). DPI formulations were made by spray drying of EMB-loaded SLNs with and without mannitol. For investigation of flowbility of the prepared powders, Carr's index and Hausner ratio, and for in vitro deposition of the powders, Next Generation Impactor (NGI) analysis were used. The encapsulation efficiency and particle size of obtained particles were higher than 98% and sub-100 nm, respectively. Toxicity investigation of EMB-loaded SLNs via MTT assay showed biocompatibility and non-toxicity of the SLNs. Results of flowability and aerodynamic traits assessment of EMB-loaded SLN DPI powder confirmed the suitability of prepared powders. Overall, the attained results showed that EMB-loaded SLN DPI has high potential for direct treatment of tuberculosis.

Use of Lipid Nanocarriers to Improve Oral Delivery of Vitamins

The chemical environment and enzymes in the gastrointestinal (GI) membrane limit the oral absorption of some vitamins. The GI epithelium also contributes to the poor permeability of numerous antioxidant agents. Thus, lipophilic vitamins do not readily dissolve in the GI tract, and therefore they have low bioavailability. Nanomedicine has the potential to improve the delivery efficiency of oral vitamins. In particular, the use of lipid nanocarriers for certain vitamins that are administered orally can provide improved solubility, chemical stability, epithelium permeability and bioavailability, half-life, nidus targeting, and fewer adverse effects. These lipid nanocarriers include self-emulsifying drug delivery systems (SEDDSs), nanoemulsions, microemulsions, solid lipid nanoparticles (SLNs), and nanostructured lipid carriers (NLCs). The use of nontoxic excipients and sophisticated material engineering of lipid nanosystems allows for control of the physicochemical properties of the nanoparticles and improved GI permeation via mucosal or lymphatic transport. In this review, we highlight recent progress in the development of lipid nanocarriers for vitamin delivery. In addition, the same lipid nanocarriers used for vitamins may also be effective as carriers of vitamin derivatives, and therefore enhance their oral bioavailability. One example is the incorporation of d-α-tocopheryl polyethylene glycol succinate (TPGS) as the emulsifier in lipid nanocarriers to increase the solubility and inhibit P-glycoprotein (P-gp) efflux. We also survey the concepts and discuss the mechanisms of nanomedical techniques that are used to develop vitamin-loaded nanocarriers.

RNAi-based therapeutics for lung cancer: biomarkers, microRNAs, and nanocarriers

INTRODUCTION

Despite the current advances in the discovery of the lung cancer biomarkers and, consequently, in the diagnosis, this pathology continues to be the primary cause of cancer-related death worldwide. In most cases, the illness is diagnosed in an advanced stage, which limits the current treatment options available and reduces the survival rate. Therefore, RNAi-based therapy arises as a promising option to treat lung cancer.

AREAS COVERED

This review provides an overview on the exploitation of lung cancer biology to develop RNAi-based therapeutics to be applied in the treatment of lung cancer. Furthermore, the review analyzes the main nanocarriers designed to deliver RNAi molecules and induce antitumoral effects in lung cancer, and provides updated information about current RNAi-based therapeutics for lung cancer in clinical trials.

EXPERT OPINION

RNAi-based therapy uses nanocarriers to perform a targeted and efficient delivery of therapeutic genes into lung cancer cells, by taking advantage of the known biomarkers in lung cancer. These therapeutic genes are key regulatory molecules of crucial cellular pathways involved in cell proliferation, migration, and apoptosis. Thereby, the characteristics and functionalization of the nanocarrier and the knowledge of lung cancer biology have direct influence in improving the therapeutic effect of this therapy.

PAMAM dendrimers as efficient drug and gene delivery nanosystems for cancer therapy

Drug delivery systems for cancer chemotherapy are employed to improve the effectiveness and decrease the side-effects of highly toxic drugs. Most chemotherapy agents have indiscriminate cytotoxicity that affects normal, as well as cancer cells. To overcome these problems, new more efficient nanosystems for drug delivery are increasingly being investigated. Polyamidoamine (PAMAM) dendrimers are an example of a versatile and reproducible type of nanocarrier that can be loaded with drugs, and modified by attaching target-specific ligands that recognize receptors that are over-expressed on cancer cells. PAMAM dendrimers with a high density of cationic charges display electrostatic interactions with nucleic acids (DNA, siRNA, miRNA, etc.), creating dendriplexes that can preserve the nucleic acids from degradation. Dendrimers are prepared by conducting several successive "generations" of synthetic reactions so their size can be easily controlled and they have good uniformity. Dendrimers are particularly well-suited to co-delivery applications (simultaneous delivery of drugs and/or genes). In the current review, we discuss dendrimer-based targeted delivery of drugs/genes and co-delivery systems mainly for cancer therapy.