Protective effect of drug delivery systems against the enzymatic degradation of dermally applied DNAzyme

A novel 5-Fluorocuracil multiple-nanoemulsion used for the enhancement of oral bioavailability in the treatment of colorectal cancer

5-Fluorouracil (5-FU) is a drug of choice for colorectal-cancer. But oral therapeutic efficacy of 5-FU is restricted due to their very little bioavailability because of poor membrane permeability and GIT-absorption. We have developed a multiple nanoemulsion (w/o/w i.e. 5-FU-MNE) in which 5-FU incorporated to improve their oral-absorption. Globule-size of opt-5-FU-MNE was 51.64 ± 2.61 nm with PDI and ZP 0.101 ± 0.001 and −5.59 ± 0.94, respectively. In vitro 5-FU-release and ex vivo permeation studies exhibited 99.71% release and 83.64% of 5-FU from opt-nanoformulation. Cytotoxic in vitro studies-exhibited that 5-FU in opt-5-FU-MNE was 5-times more potent than 5-FU-S on human-colon-cancer-cell-lines (HT-29). The enhanced C_max with AUC_0-8h with opt-5-FU-MNE was shown extremely significant (p < 0.001) in wistar rat’s plasma in the comparison of oral and i.v. treated group of 5-FU-S by PK-observations. Furthermore, opt-5-FU-MNE was showed much more significant (p < 0.001) results as compared to 5-FU-S (free) on cell lines for human colon cancer (HT-29).

Graphene Oxide as a Nanocarrier for Biochemical Molecules: Current Understanding and Trends

The development of an advanced and efficient drug delivery system with significant improvement in its efficacy and enhanced therapeutic value is one of the critical challenges in modern medicinal biology. The integration of nanomaterial science with molecular and cellular biology has helped in the advancement and development of novel drug delivery nanocarrier systems with precision and decreased side effects. The design and synthesis of nanocarriers using graphene oxide (GO) have been rapidly growing over the past few years. Due to its remarkable physicochemical properties, GO has been extensively used in efforts to construct nanocarriers with high specificity, selectivity, and biocompatibility, and low cytotoxicity. The focus of this review is to summarize and address recent uses of GO-based nanocarriers and the improvements as efficient drug delivery systems. We briefly describe the concepts and challenges associated with nanocarrier systems followed by providing critical examples of GO-based delivery of drug molecules and genes. Finally, the review delivers brief conclusions on the current understanding and prospects of nanocarrier delivery systems.

Ultra-deformable Liposomes as Flexible Nanovesicular Carrier to Penetrate Versatile Drugs Transdermally

Introduction:

Transferosomes also known as ultra-deformable liposomes were introduced by Gregor Cevc in 1990. These are deformable vesicles that transport drug across the skin, which is the best route of drug delivery because skin is the largest human organ with 3 kg total weight and a surface area of 1.5-2.0 m2.

Methods:

Transferosomes are able to efficiently deliver low as well as high molecular weight drug across the skin in terms of quantity and depth. Various methods used for the preparation of transferosomes such as thin film hydration method, reverse phase evaporation method, vortex/sonication method, ethanol injection method and freeze thaw method.

Results:

The prepared transferosomal preparation will be evaluated for particle shape and size, entrapment efficiency, stability study, penetration ability and skin permeation study. In vitro release studies are to be performed using a specific dissolution medium.

Conclusion:

Ultra deformable liposomes can be used for delivery of different drugs e.g. analgesic, anesthetic, corticosteroids, anticancer, sex hormone, insulin, gap junction protein, and albumin.

Delivery of therapeutic RNA-cleaving oligodeoxyribonucleotides (deoxyribozymes): from cell culture studies to clinical trials

INTRODUCTION

Development of efficient in vivo delivery systems remains a major challenge en route to clinical application of antisense technology, including RNA-cleaving molecules such as deoxyribozymes (DNAzymes). The mechanisms of oligonucleotide uptake and trafficking are clearly dependent on cell type and the type of oligonucleotide analogue. It appears likely that each particular disease target would pose its own specific requirements for a delivery method. Areas covered. In this review we will discuss the available options for DNAzyme delivery in vitro and in vivo, outline various exogenous and endogenous strategies that have been, or are still being, developed and ascertain their applicability with emphasis on those methods that are currently being used in clinical trials. Expert opinion. The available information suggests that a practical system for in vivo delivery has to be biodegradable, as to minimize concerns over long-term toxicity, it should not accumulate in the organism. Extracellular vesicles may offer the most organic way for drug delivery especially as they can be fused with artificial liposomes to produce hybrid nanoparticles. Chemical modification of DNAzymes holds great potential to apply oligonucleotide analogs that would not only be resistant to nuclease digestion, but also able to penetrate cells without external delivery agents.

The molecular assembly of the ionic liquid/aliphatic carboxylic acid/aliphatic amine as effective and safety transdermal permeation enhancers

In spite of numerous advantages, transdermal drug delivery systems are unfeasible for most drugs because of the barrier effect of the stratum corneum. Ionic liquids were recently used to enhance transdermal drug delivery by improving drug solubility. In the present study, safe and effective ionic liquids for transdermal absorption were obtained as salts generated by a neutralization reaction between highly biocompatible aliphatic carboxylic acids (octanoic acid or isostearic acid) and aliphatic amines (diisopropanolamine or triisopropanolamine) (Medrx Co., Ltd., 2009). The mechanism of skin permeability enhancement by ionic liquids was investigated by hydrophilic phenol red and hydrophobic tulobuterol. Further, the skin permeation enhancing effect was remarkably superior in the acid excess state rather than the neutralization state. Infrared absorption spectrum analysis confirmed that ionic liquids/aliphatic carboxylic acid/aliphatic amine are coexisting at all mixing states. In the acid excess state, ionic liquids interact with aliphatic carboxylic acids via hydrogen bonds. Thus, the skin permeation enhancing effect is not caused by the ionic liquid alone. The "liquid salt mixture," referred to as a complex of ingredients coexisting with ionic liquids, forms a molecular assembly incorporating hydrophilic drug. This molecular assembly was considered an effective and safety enhancer of transdermal drug permeation.

Biocompatible and biodegradable fibrinogen microspheres for tumor-targeted doxorubicin delivery

In the development of effective drug delivery carriers, many researchers have focused on the usage of nontoxic and biocompatible materials and surface modification with targeting molecules for tumor-specific drug delivery. Fibrinogen (Fbg), an abundant glycoprotein in plasma, could be a potential candidate for developing drug carriers because of its biocompatibility and tumor-targeting property via arginine–glycine–aspartate (RGD) peptide sequences. Doxorubicin (DOX), a chemotherapeutic agent, was covalently conjugated to Fbg, and the microspheres were prepared. Acid-labile and non-cleavable linkers were used for the conjugation of DOX to Fbg, resulting in an acid-triggered drug release under a mild acidic condition and a slow-controlled drug release, respectively. In vitro cytotoxicity tests confirmed low cytotoxicity in normal cells and high antitumor effect toward cancer cells. In addition, it was discovered that a longer linker could make the binding of cells to Fbg drug carriers easier. Therefore, DOX–linker–Fbg microspheres could be a suitable drug carrier for safer and effective drug delivery.

Inorganic nanovectors for nucleic acid delivery

Nucleic acids show immense potential to treat cancer, acquired immune deficiency syndrome, neurological diseases and other incurable human diseases. Upon systemic administration, they encounter a series of barriers and hence barely reach the site of action, the cell. Intracellular delivery of nucleic acids is facilitated by nanovectors, both viral and non-viral. A major advantage of non-viral vectors over viral vectors is safety. Nanovectors evaluated specifically for nucleic acid delivery include polyplexes, lipoplexes and other cationic carrier-based vectors. However, more recently there is an increased interest in inorganic nanovectors for nucleic acid delivery. Nevertheless, there is no comprehensive review on the subject. The present review would cover in detail specific properties and types of inorganic nanovectors, their preparation techniques and various biomedical applications as therapeutics, diagnostics and theranostics. Future prospects are also suggested.

Deformable liposomes by reverse-phase evaporation method for an enhanced skin delivery of (+)-catechin

BACKGROUND

(+)-catechin, as the most common catechin isomer, is recognized to be an antioxidant which benefits the skin in many ways. The purpose of the present study was to prepare and evaluate a suitable liposomal delivery systems for (+)-catechin topical application.

METHODS

In this study, catechin-loaded conventional liposomal delivery system, deformable conventional liposomal delivery system and deformable liposomes prepared by reverse-phase evaporation (REV) method were compared. The three systems were characterized for liposome particle size, zeta-potential, entrapment efficiency, drug release, permeability across porcine skin and catechin deposition in the skin.

RESULTS

It was revealed that the size of deformable conventional liposomes before freeze-drying and deformable REV liposomes after freeze-drying range from 335.6 ± 71.7 nm to 551.1 ± 53.4 nm, respectively, which were considered to be suitable for skin delivery. The deformable REV liposomes had a higher aqueous volume and thus were able to entrap greater amounts of hydrophilic (+)-catechin (50.0 ± 5.9%) compared to conventional (30.0 ± 3.8%) and deformable conventional liposomes (36.1 ± 4.6%). All liposomal formulations exhibited a prolonged catechin release. Compared to deformable liposomes, the REV deformable liposomes showed a significantly better deposition of (+)-catechin while catechin solution did not permeate into the porcine ear skin.

CONCLUSION

Among all formulations studied, deformable REV liposomes were considered to be favorable for catechin topical delivery.