Maltodextrin-based proniosomes

Characterization of withanolides and bacoside A-loaded proniosomes: effect on oxidative stress and survival under hypergravity in rodent model

OBJECTIVE

This work provides characterization of withanolides and bacoside A proniosomes, and evaluating their potency in rat model for combating oxidative stress-induced blood-brain barrier (BBB) damage and their survival under hypergravity.

SIGNIFICANCE

The delivery system was aimed for sustained drug release in plasma and brain, which could improve their efficiency and provide a therapeutic approach to combat oxidative damage and restore BBB integrity.

METHODS

Proniosomes were prepared using withanolides extracted from the roots of W. somnifera and bacoside A derived from the leaf extract of B. monnieri by thin film hydration technique. In vitro release of withanolides and bacoside A from the proniosomes was studied. In vivo experiments were conducted in Wistar Albino rat model to evaluate the efficacy of drug-loaded proniosomes in improving the antioxidant activity in plasma and brain, restoring BBB integrity and combating hypergravity conditions.

RESULTS

The withanolides and bacoside A-loaded proniosomes showed slow and sustained release of just 62.0 ± 2.87 and 62.9 ± 3.41%, respectively, in 9 h period against the release of 98-99% for the extracts that served as control. Trials conducted in vivo revealed a significant (p < .05) increase in the activity of antioxidant enzymes in both plasma and brain. Also, minimal extravasation of Evans blue dye into the brain (15 ± 0.03 and 16 ± 0.03 ng/g in treated groups against 110 ± 0.01 ng/g in control) of the rats fed with drug-loaded proniosomes was indicative of minimal damage to BBB. Rats fed with drug-loaded proniosomes survived to the extent of 75-83.3% against simulated hypergravity as compared to the control group in which only 50% survived.

CONCLUSION

Proniosomes provided sustained release of drugs, which helped to protect BBB integrity, thereby combating hypergravity.

An Engineered Specificity of Anti-Neoplastic Agent Loaded Magnetic Nanoparticles for the Treatment of Breast Cancer

Nanoparticles have gained increased attention due to the prospection of drug delivery at target sites, thus limiting the systemic effects of the drugs. Their efficiency was further improved by adding special carriers such as magnetite (Fe3O4). It is one of the extensively used oxides of iron for both pharmaceutical and biomedical applications owing to its ease of preparation and biocompatibility. In this work, Gemcitabine magnetic nanoparticles were prepared using Fe3O4 and chitosan as the primary ingredients. Optimization was accomplished by Box-Behnken Design and factor interactions were evaluated. The desirability function approach was made to enhance the formulation concerning particle size, polydispersity index, and zeta potential. Based on this, optimized magnetic nanoparticles (O-MNP) were formulated with 300 mg of Fe3O4, 297.7 mg of chitosan, and a sonication time of 2.4 h, which can achieve the prerequisites of the target formulation. All other in vitro parameters were found to be following the requirement. In vitro cytotoxic studies for O-MNP were performed using cell cultures of breast cancer (MCF-7), leukemia (THP-1), prostate cancer (PC-3), and lung cancer (A549). O-MNP showed maximum inhibition growth with MCF-7 cell lines rather than other cell lines. The data observed here demonstrates the potential of magnetic nanoparticles of gemcitabine in treating breast cancers.

Recent advances of non-ionic surfactant-based nano-vesicles (niosomes and proniosomes): a brief review of these in enhancing transdermal delivery of drug

Background

Hepatic first-pass metabolism and poor therapeutic efficiency at targeted region are the endemic problems of new drug molecules. Thus, comprehensive research has been carried out on the novel vesicular drug delivery systems in nanotechnology from the last few years. These nano-carrier systems have developed to overcome the limitations that are associated with hepatic first-pass metabolism in conventional oral dosage forms and the barrier properties of the lipid bilayer in stratum corneum via transdermal drug delivery for improving the bioavailability of various drugs.

Main body

In recent years, several targeted vesicular drug delivery carriers are developing like liposomes, niosomes, proniosomes, transferosomes, ethosomes, and electrosomes. Among them, niosomes and proniosomes are to be better carriers to increase therapeutic efficiency and bioavailability by reducing the side effects and acting as a promising approach for transdermal drug delivery. Both are non-ionic surfactant-based vesicles and are amphiphilic. This article concisely reviews the possible mechanisms within niosomes and pronisomes to enhance transdermal drug delivery, types, composition, preparation techniques, characterizations, and its applications.

Conclusion

As per the researches done in the formulation of various nano-carrier systems through transdermal approach for the enhancement of bioavailability, it can be stated that the hepatic first pass metabolism can be reduced as well as therapeutic efficiency can be increased by many folds compared to their oral marketed formulations.

Development of Provesicular Nanodelivery System of Curcumin as a Safe and Effective Antiviral Agent: Statistical Optimization, In Vitro Characterization, and Antiviral Effectiveness

Curcumin is a natural compound that has many medical applications. However, its low solubility and poor stability could impede its clinical applications. The present study aimed to formulate dry proniosomes to overcome these pitfalls and improve the therapeutic efficacy of Curcumin. Curcumin-loaded proniosomes were fabricated by the slurry method according to 32 factorial design using Design-Expert software to demonstrate the impact of different independent variables on entrapment efficiency (EE%) and % drug released after 12 h (Q12h). The optimized formula (F5) was selected according to the desirability criteria. F5 exhibited good flowability and appeared, after reconstitution, as spherical nanovesicles with EE% of 89.94 ± 2.31% and Q12h of 70.89 ± 1.62%. F5 demonstrated higher stability and a significant enhancement of Q12h than the corresponding niosomes. The docking study investigated the ability of Curcumin to bind effectively with the active site of DNA polymerase of Herpes simplex virus (HSV). The antiviral activity and the safety of F5 were significantly higher than Curcumin. F5 improved the safety of Acyclovir (ACV) and reduced its effective dose that produced a 100% reduction of viral plaques. Proniosomes could be promising stable carriers of Curcumin to be used as a safe and efficient antiviral agent.

Glaucoma: Management and Future Perspectives for Nanotechnology-Based Treatment Modalities

Glaucoma, being asymptomatic for relatively late stage, is recognized as a worldwide cause of irreversible vision loss. The eye is an impervious organ that exhibits natural anatomical and physiological barriers which renders the design of an efficient ocular delivery system a formidable task and challenge scientists to find alternative formulation approaches. In the field of glaucoma treatment, smart delivery systems for targeting have aroused interest in the topical ocular delivery field owing to its potentiality to oppress many treatment challenges associated with many of glaucoma types. The current momentum of nano-pharmaceuticals, in the development of advanced drug delivery systems, hold promises for much improved therapies for glaucoma to reduce its impact on vision loss. In this review, a brief about glaucoma; its etiology, predisposing factors and different treatment modalities has been reviewed. The diverse ocular drug delivery systems currently available or under investigations have been presented. Additionally, future foreseeing of new drug delivery systems that may represent potential means for more efficient glaucoma management are overviewed. Finally, a gab-analysis for the required investigation to pave the road for commercialization of ocular novel-delivery systems based on the nano-technology are discussed.

Oral delivery of natural compounds by phospholipid vesicles

The purpose of this report is to summarize and critically analyze emerging trends in phospholipid vesicles for the oral delivery of natural compounds. Liposomes have long been used as delivery systems, thanks to their ability to incorporate diverse bioactives, their biocompatibility and safety. However, the efficacy of oral liposomes is hampered by their low stability under the harsh conditions of the gastrointestinal tract. Different approaches have been utilized with the aim of improving the stability of liposomes and the payload after oral administration. This report provides an overview on the phospholipid vesicles used for oral delivery of natural compounds, exploring the current strategies to improve their performance by modifying the lipid bilayer composition and assembly or the physical state.

Proniosomal Microcarriers: Impact of Constituents on the Physicochemical Properties of Proniosomes as a New Approach to Enhance Inhalation Efficiency of Dry Powder Inhalers

Proniosomes are free-flowing systems with coating carriers, which developed as a method for improving the drug flow and pulmonary delivery. Extensive research on proniosomes was done to enhance the dry powder inhalers (DPI)'s inhalation performance. This research aimed at studying the impact of lactose-mannitol mixture additives on the proniosome's physicochemical properties as a method for improving the inhalation efficiency of DPI. Vismodegib has been employed as a compound model. Box-Behnken design has been employed to prepare different proniosomes formulae by incorporating various (A) span 60 concentrations, (B) lactose concentrations and (C) mannitol: total carrier mixture. The measured responses were vesicle size (R₁), %release (R₂), Carr's index (R₃) and %recovery (R₄). The results displayed that R₁ and R₄ were significantly antagonistic to C and significantly synergistic to both A and B while R₂ and R₃ were significantly synergistic to C and significantly antagonistic to both A and B. The optimal formula was selected for its aerodynamic behaviour, cytotoxic activity and bioavailability assessment. The optimal formula resulted in better Vismodegib lung deposition, cytotoxic activity and relative bioavailability. This novel formula could be a promising carrier for sustained delivery of drugs via the pulmonary route.

Proniosomes as a Carrier System for Transdermal Delivery of Clozapine

The current study aimed to formulate the clozapine (CLZ) loaded proniosomal gel (PN) and evaluate it's in vitro release, ex vivo permeation and gel properties. CLZ is a BCS class II drug with low bioavailability of 27% and severe adverse drug reactions (ADRs) due to frequent dosing. Proniosomes offer a versatile pro-vesicular approach with potential in transdermal drug delivery. PN-CLZ gel was prepared by the coacervation phase separation method utilizing span-60, cholesterol and lecithin. Optimization of PN gel was done by hit & trial method and the formulations were characterized for particle size, entrapment efficiency (EE), polydispersity index (PDI) and zeta potential (ZP). The optimized formulation had the highest entrapment efficiency of 90% and the average particle size of approx. 325 nm. PDI reflected homogeneity in the formulation. ZP was -59.76 mV, high enough to indicate a stable formulation. The in vitro release studies manifested a sustained release behavior of clozapine from the proniosomal gel. The ex vivo permeation showed noteworthy permeation of the drug through stratum corneum with a steady state flux of 18.26 ug/cm2/hr. The optimized gel was analyzed for pH, spreadability, bioadhesion and rheology. The results suggested that clozapine could be effectively loaded into proniosomal gel for administration through skin.

Quality by Design for the Development and Analysis of Enhanced In-Situ Forming Vesicles for the Improvement of the Bioavailability of Fexofenadine HCl in Vitro and in Vivo

Drug absorption from the gastrointestinal tract (GIT) is one of the major problems affecting the bioavailability of orally absorbed drugs. This work aims to enhance Fexofenadine HCl oral bioavailability in vivo, the drug used for allergic rhinitis. In this study, novel spray-dried lactose-based enhanced in situ forming vesicles were prepared using different absorption enhancer by the slurry method. Full factorial design was used to obtain an optimized formulation, while central composite design was used to develop economic, environment-friendly analysis method of Fexofenadine HCl in plasma of rabbits. The optimized formulation containing Capryol 90 as absorption enhancer has a mean particle size 202.6 ± 3.9 nm and zeta potential -31.6 ± 0.9 mV. It achieved high entrapment efficiency of the drug 73.7 ± 1.7% and rapid Q3h release reaches 71.5 ± 2.7%. The design-optimized HPLC assay method in rabbit plasma could separate Fexofenadine HCl from endogenous plasma compounds in less than 3.7 min. The pharmacokinetic study and the pharmacological effect of the fexofenadine-loaded optimized formulation showed a significant increase in blood concentration and significantly higher activity against compound 48/80 induced systemic anaphylaxis-like reactions in mice. Therefore, enhanced in situ forming vesicles were effective nanocarriers for the entrapment and delivery of Fexofenadine HCl.

Synthesis, Characterization, and Dynamic Behavior of Well-defined Dithiomaleimide-functionalized Maltodextrins

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Maltodextrins have an increasing number of biomedical and industrial applications due to their attractive physicochemical properties such as biodegradability and biocompatibility. Herein, we describe the development of a synthetic pathway and characterization of thiol-responsive maltodextrin conjugates with dithiomaleimide linkages. 19F NMR studies were also conducted to demonstrate the exchange dynamics of the dithiomaleimide-functionalized sugar end groups.

Proniosomal gel-derived niosomes: an approach to sustain and improve the ocular delivery of brimonidine tartrate; formulation, in-vitro characterization, and in-vivo pharmacodynamic study

Brimonidine tartrate (BRT) is a hydrophilic α2 adrenergic agonist used for the treatment of glaucoma. Glaucoma is an ocular disease affecting the anterior segment of the eye requiring lifetime treatment. Owing to the obstacles facing ocular delivery systems and hydrophilicity of BRT, frequent administration of the eye drops is required. Niosomes have been widely used to improve the ocular bioavailability of the topically applied drugs and to enhance the ocular residence time. However, they have drawbacks as physical instability, aggregation, and loss of the entrapped drug. For this reason, BRT proniosomes were prepared to overcome niosomal instability issues. A D-optimal design was utilized to determine the optimum conditions for preparation of the proniosomal gels. Independent variables were amount of surfactant, surfactant:cholesterol ratio, and type of surfactant used. The dependent variables were entrapment efficiency (EE%), particle size, percentage of drug released after 2 h (Q2h), and percentage of drug released after 24 h (Q24h). The optimum formula was suggested with desirability 0.732 and the composition of 540 mg Span 60 and 10:1 surfactant:cholesterol ratio. The results obtained after reconstitution were; EE% of 79.23 ± 1.12% particle size of 810.95 ± 16.758 nm, polydispersity index (PDI) 0.6785 ± 0.213, zeta potential 59.1 ± 0.99 mV, Q2h40.98 ± 1.29%, Q8h 63.35 ± 6.07%, and Q24h = 91.11 ± 1.76%. Transmission electron microscope imaging of the formula showed the typical spherical shape of niosomes. In-vivo pharmacodynamic study assured the improved ocular bioavailability of BRT selected formula when compared with Alphagan®P with relative AUC0-24 of 5.024 and 7.90 folds increase in the mean residence time (MRT). Lack of ocular irritation of the formula was assured by Draize test.

Optimization of Aceclofenac Proniosomes by Using Different Carriers, Part 1: Development and Characterization

In the contemporary medical model world, the proniosomal system has been serving as a new drug delivery system that is considered to significantly enhance the bioavailability of drugs with low water solubility. The application of this system can improve the bioavailability of aceclofenac that is used for the relief of pain and inflammation in osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis. The present study is intended to develop an optimized proniosomal aceclofenac formula by the use of different carriers. Aceclofenac proniosomes have been prepared by slurry method, and different carriers such as maltodextrin, mannitol, and glucose were tried. Prepared proniosomes characterized by differential scanning calorimetry (DSC) analysis and Fourier transform infrared (FTIR) analysis revealed the compatibility of the drug chosen with the ingredient added, powder X-ray diffractometry (XRD) confirmed the amorphous phase of the prepared proniosomes, and finally, the surfactant layer was observed by scanning electron microscopy (SEM). Aceclofenac physical state transformations were confirmed with all formulas but maltodextrin proniosomes exhibited solubility more than other formulations. HPLC method has been used to analyze the niosomes derived from proniosomes in terms of their entrapment capability and drug content. The obtained results revealed that aceclofenac proniosomes can be successfully prepared by using different carriers.

Proniosomal gel-mediated topical delivery of fluconazole: Development, in vitro characterization, and microbiological evaluation

The aim of this study was to explore the potential of proniosomal gel for topical delivery of fluconazole, an antifungal drug used in fungal infections caused by pathogenic fungi. Fluconazole-loaded proniosomal gels were prepared by the coacervation phase separation method using different nonionic surfactants (spans and tweens). The prepared fluconazole proniosomal gels were evaluated for various parameters such as particle size (PS), drug entrapment efficiency percentage (EE%), and in vitro drug release. The experimental results showed that the EE% for the prepared formulae are acceptable (85.14%–97.66%) and they are nanosized (19.8–50.1 nm) and the diffusion from the gels gave the desired sustaining effect. F4, which was prepared from span 60, tween 80 (1:1), and cholesterol showed highest EE% and gave slow release (40.50% ± 1.50% after 6 h), was subjected to zeta potential (ZP) test, transmission electron microscopy as well as microbiological study. The results showed a well-defined spherical vesicle with sharp boundaries with good physical stability of fluconazole within the prepared gel. Moreover, F4 showed an excellent microbiological activity represented by a greater zone of inhibition (5.3 cm) compared to control gel (fluconazole in 2% hydroxy propyl methyl cellulose (HPMC) gel formula) (4.2 cm) and plain gel with no drug (0 cm) against Candida albicans. This study showed the suitability of the proniosomal gel in attaining the desired sustainment effect for topical delivery of fluconazole for the management of fungal infection. The physical stability study showed that there was no significant change in EE%, PS, and ZP of fluconazole proniosomal gel after storage for 6 months.

Enhancement of Dissolution and Skin Permeability of Pentazocine by Proniosomes and Niosomal Gel

Proniosomes (PN) are the dry water-soluble carrier systems that may enhance the oral bioavailability, stability, and topical permeability of therapeutic agents. The low solubility and low oral bioavailability due to extensive first pass metabolism make Pentazocine as an ideal candidate for oral and topical sustained release delivery. The present study was aimed to formulate the PNs by quick slurry method that are converted to niosomes (liquid dispersion) by hydration, and subsequently formulated to semisolid niosomal gel. The PNs were found in spherical shape in the SEM and stable in the physicochemical and thermal analysis (FTIR, TGA, and XRD). The quick slurry method produced high recovery (> 80% yield) and better flow properties (θ = 28.1-37.4°). After hydration, the niosomes exhibited desirable entrapment efficiency (44.45-76.23%), size (4.98-21.3 μm), and zeta potential (- 9.81 to - 21.53 mV). The in vitro drug release (T_100%) was extended to more than three half-lives (2-4 h) and showed good fit to Fickian diffusion indicated by Korsmeyer-Peppas model (n = 0.136-0.365 and R² = 0.9747-0.9954). The permeation of niosomal gel was significantly enhanced across rabbit skin compared to the pure drug-derived gel. Therefore, the PNs are found promising candidates for oral as dissolution enhancement and sustained release for oral and topical delivery of pentazocine for the management of cancer pain.

Technology overview and drug delivery application of proniosome

Rapid advancement in the field of colloidal science has shown a great progress in the development of proniosome technology (PT) as an impending drug delivery system. PT is a valuable carrier system for delivery of hydrophobic as well as hydrophilic drugs. It is a liquid crystalline compact niosomal hybrid, which upon hydration gives niosomes. They can augment the bioavailability of encapsulated drug and provide better therapeutic activity in a controlled manner. Non-toxicity, penetration enhancing the effect of surfactant and modified drug release from the proniosomal transdermal gel has attracted a greater attention of formulation scientist toward PT. Free flowing dry proniosomal powder are suitable for unit dosage forms such as tablet and capsules. Proniosomes are auspicious drug delivery system for the future. Proniosomes-derived niosomes are a better alternative to the other vesicular system due to their superior physicochemical stability and effective drug delivery capability. The focus of this review is to bring out all the aspects of proniosomes including their different compositions, various methods of preparation, characterization and recent development in their therapeutic applications.

Provesicular granisetron hydrochloride buccal formulations: in vitro evaluation and preliminary investigation of in vivo performance

Granisetron hydrochloride (granisetron) is a potent antiemetic that has been proven to be effective in acute and delayed emesis in cancer chemotherapy. Granisetron suffers from reduced oral bioavailability (≈60%) due to hepatic metabolism. In this study the combined advantage of provesicular carriers and buccal drug delivery has been explored aiming to sustain effect and improve bioavailability of granisetron via development of granisetron provesicular buccoadhesive tablets with suitable quality characteristics (hardness, drug content, in vitro release pattern, exvivo bioadhesion and in vivo bioadhesion behavior). Composition of the reconstituted niosomes from different prepared provesicular carriers regarding type of surfactant used and cholesterol concentration significantly affected both entrapment efficiency (%EE) and vesicle size. Span 80 proniosome-derived niosomes exhibited higher encapsulation efficiency and smaller particle size than those derived from span 20. Also, the effect of %EE and bioadhesive polymer type on in vitro drug release and in vivo performance of buccoadhesive tablets was investigated. Based on achievement of required in vitro release pattern (20-30% at 2h, 40-65% at 6h and 80-95% at 12h), in vivo swelling behavior, and in vivo adhesion time (>14 h) granisetron formulation (F19, 1.4 mg) comprising HPMC:carbopol 974P (7:3) and maltodextrin coated with the vesicular precursors span 80 and cholesterol (9:1) was chosen for in vivo study. In vivo pharmacokinetic study revealed higher bioavailability of buccal formulation relative to conventional oral formulation of granisetron (AUC0-∞ is 89.97 and 38.18 ng h/ml for buccal and oral formulation, respectively). A significantly lower and delayed Cmax (12.09±4.47 ng/ml, at 8h) was observed after buccal application compared to conventional oral tablet (31.66±10.15 ng/ml, at 0.5 h). The prepared provesicular buccoadhesive tablet of granisetron (F19) might help bypass hepatic first-pass metabolism and improve bioavailability of granisetron with the possibility of reducing reported daily dose (2mg) and reducing dosing frequency.

Niosomes from 80s to present: the state of the art

Efficient and safe drug delivery has always been a challenge in medicine. The use of nanotechnology, such as the development of nanocarriers for drug delivery, has received great attention owing to the potential that nanocarriers can theoretically act as "magic bullets" and selectively target affected organs and cells while sparing normal tissues. During the last decades the formulation of surfactant vesicles, as a tool to improve drug delivery, brought an ever increasing interest among the scientists working in the area of drug delivery systems. Niosomes are self assembled vesicular nanocarriers obtained by hydration of synthetic surfactants and appropriate amounts of cholesterol or other amphiphilic molecules. Just like liposomes, niosomes can be unilamellar or multilamellar, are suitable as carriers of both hydrophilic and lipophilic drugs and are able to deliver drugs to the target site. Furthermore, niosomal vesicles, that are usually non-toxic, require less production costs and are stable over a longer period of time in different conditions, so overcoming some drawbacks of liposomes. The niosome properties are specifically dictated by size, shape, and surface chemistry which are able to modify the drug's intrinsic pharmacokinetics and eventual drug targeting to the areas of pathology. This up-to-date review deals with composition, preparation, characterization/evaluation, advantages, disadvantages and application of niosomes.

Proliposome powders for enhanced intestinal absorption and bioavailability of raloxifene hydrochloride: effect of surface charge

The primary goal of the present study was to investigate the combined prospective of proliposomes and surface charge for the improved oral delivery of raloxifene hydrochloride (RXH). Keeping this objective, the present systematic study was focused to formulate proliposomes by varying the ratio of hydrogenated soyphosphatidylcholine and cholesterol. Furthermore, to assess the role of surface charge on improved absorption of RXH, anionic and cationic vesicles were prepared using dicetyl phosphate and stearylamine, respectively. The formulations were characterized for size, zeta potential and entrapment efficiency. The improved dissolution characteristics assessed from dissolution efficiency, mean dissolution rate were higher for proliposome formulations. The solid state characterization studies indicate the transformation of native crystalline form of the drug to amorphous and/or molecular state. The higher effective permeability coefficient and fraction absorbed in humans extrapolated from in situ single-pass intestinal absorption study data in rats provide an insight on the potential of proliposomes and cationic surface charge for augment in absorption across gastro intestinal barrier. To draw the conclusions, in vivo pharmacokinetic study carried out in rats indicate a threefold enhancement in the rate and extent of absorption of RXH from cationic proliposome formulation which unfurl the potential of proliposomes and role of cationic charge for improved oral delivery of RXH.

Synthesis, characterization and toxicological evaluation of maltodextrin capped cadmium sulfide nanoparticles in human cell lines and chicken embryos

BACKGROUND

Semiconductor Quantum dots (QDs) have become quite popular thanks to their properties and wide use in biological and biomedical studies. However, these same properties entail new challenges in understanding, predicting, and managing potential adverse health effects following exposure. Cadmium and selenium, which are the major components of the majority of quantum dots, are known to be acutely and chronically toxic to cells and organisms. Protecting the core of nanoparticles can, to some degree, control the toxicity related to cadmium and selenium leakage.

RESULTS

This study successfully synthesized and characterized maltodextrin coated cadmium sulfide semiconductor nanoparticles. The results show that CdS-MD nanoparticles are cytotoxic and embryotoxic. CdS-MD nanoparticles in low concentrations (4.92 and 6.56 nM) lightly increased the number of HepG2 cell. A reduction in MDA-MB-231 cells was observed with concentrations higher than 4.92 nM in a dose response manner, while Caco-2 cells showed an important increase starting at 1.64 nM. CdS-MD nanoparticles induced cell death by apoptosis and necrosis in MDA-MD-231 cells starting at 8.20 nM concentrations in a dose response manner. The exposure of these cells to 11.48-14.76 nM of CdS-MD nanoparticles induced ROS production. The analysis of cell proliferation in MDA-MB-231 showed different effects. Low concentrations (1.64 nM) increased cell proliferation (6%) at 7 days (p < 0.05). However, higher concentrations (>4.92 nM) increased cell proliferation in a dose response manner (15-30%) at 7 days. Exposures of chicken embryos to CdS-MD nanoparticles resulted in a dose-dependent increase in anomalies that, starting at 9.84 nM, centered on the heart, central nervous system, placodes, neural tube and somites. No toxic alterations were observed with concentrations of < 3.28 nM, neither in cells nor chicken embryos.

CONCLUSIONS

Our results indicate that CdS-MD nanoparticles induce cell death and alter cell proliferation in human cell lines at concentrations higher than 4.92 nM. We also demonstrated that they are embryotoxic. However, no toxic effects were observed with doses lower than 3.28 nM in neither cells nor chicken embryos. The CdS-MD nanoparticles used in this study can be potentially used in bio-imaging applications. However, further studies using mammalian species are required in order to discard more toxic effects.

Lipoidal soft hybrid biocarriers of supramolecular construction for drug delivery

Lipid-based innovations have achieved new heights during the last few years as an essential component of drug development. The current challenge of drug delivery is liberation of drug agents at the right time in a safe and reproducible manner to a specific target site. A number of novel drug delivery systems has emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery. Microparticulate lipoidal vesicular system represents a unique technology platform suitable for the oral and systemic administration of a wide variety of molecules with important therapeutic biological activities, including drugs, genes, and vaccine antigens. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. Also, novel lipid carrier-mediated vesicular systems are originated. This paper has focused on the lipid-based supramolecular vesicular carriers that are used in various drug delivery and drug targeting systems.

Lipoidal soft hybrid biocarriers of supramolecular construction for drug delivery

Lipid-based innovations have achieved new heights during the last few years as an essential component of drug development. The current challenge of drug delivery is liberation of drug agents at the right time in a safe and reproducible manner to a specific target site. A number of novel drug delivery systems has emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery. Microparticulate lipoidal vesicular system represents a unique technology platform suitable for the oral and systemic administration of a wide variety of molecules with important therapeutic biological activities, including drugs, genes, and vaccine antigens. The success of liposomes as drug carriers has been reflected in a number of liposome-based formulations, which are commercially available or are currently undergoing clinical trials. Also, novel lipid carrier-mediated vesicular systems are originated. This paper has focused on the lipid-based supramolecular vesicular carriers that are used in various drug delivery and drug targeting systems.

Transdermal absorption enhancement of rice bran bioactive compounds entrapped in niosomes

Niosomes composed of Tween 61 and cholesterol at 1:1 molar ratio were entrapped with the mixture of the three semi-purified rice (Oryza sativa L., Family Gramineae) bran bioactive compounds [ferulic acid (F), γ-oryzanol (O), and phytic acid (P)] at 0.5%, 1.5%, and 1.5%, respectively, by the supercritical CO(2) technique. The transdermal absorption by vertical Franz diffusion cells of the compounds entrapped in niosomes (Nio FOP), the unentrapped compounds (Mixed FOP), the compounds incorporated in gel and cream (Gel FOP and Cream FOP), and the compounds entrapped in niosomes and incorporated in gel and cream (Gel nio and Cream nio) was investigated. At 6 h, F and P from Nio FOP gave lower cumulative amount in viable epidermis and dermis (VED) than from Mixed FOP of 1.1 and 1.6 times, respectively, while O from Nio FOP exhibited higher cumulative amount in VED than from Mixed FOP of 2.4 times. The highest cumulative amount in VED of F, O, and P were from Gel nio, Cream nio, and Mixed FOP at 1.564 ± 0.052, 15.972 ± 0.273, and 25.857 ± 0.025 ng/cm(2), respectively. Niosomes enhanced the transdermal absorption of the hydrophobic compound O, while retarded the hydrophilic compounds F and P indicating the less systemic risk of F and P than O when entrapped in niosomes. Thus, transdermal absorption of F, O, and P appeared to depend on niosomal size, lipophilicity of the bioactive compounds, and types of formulations. These preclinical results can be applied for the design of the clinical study of the developed rice bran niosomal topical products.

Formulation and optimization of Zidovudine niosomes

Zidovudine (AZT) is commonly used to treat patients with AIDS, but it is limited by toxicity and high dosing needs. Alternative formulations have been proposed to overcome these drawbacks. The objective of this study was to evaluate process-related variables like hydration and sonication time, rotation speed of evaporation flask, and the effects of charge-inducing agent and centrifugation on zidovudine entrapment and release from niosomes. Formulation of zidovudine niosomes was optimized by altering the proportions of Tween, Span and cholesterol. The effect of process-related variables like hydration time, sonication time, charge-inducing agent, centrifugation and rotational speed of evaporation flask on zidovudine entrapment and release from niosomes was evaluated. The effect of changes in osmotic shock and viscosity were also evaluated. Non-sonicated niosomes were in the size range of 2-3.5 μm and sonicated niosomes formulated with Tween 80 and dicetylphosphate (DCP) had a mean diameter of 801 nm. Zidovudine niosomes formulated with Tween 80 entrapped high amounts of drug and the addition of DCP enhanced drug release for a longer time (88.72% over 12 h). The mechanism of release from Tween 80 formulation was the Fickian type and obeyed first-order release kinetics. Niosomes can be formulated by proper adjustment of process parameters to enhance zidovudine entrapment and sustainability of release. These improvements in zidovudine formulation may be useful in developing a more effective AIDS therapy.

Formulation and optimization of piroxicam proniosomes by 3-factor, 3-level Box-Behnken design

The aim of this study was to investigate the combined influence of 3 independent variables in the preparation of piroxicam proniosomes by the slurry method. A 3-factor, 3-level Box-Behnken design was used to derive a second-order polynomial equation and construct contour plots to predict responses. The independent variables selected were molar ratio of Span 60:cholesterol (X(1)), surfactant loading (X(2)), and amount of drug (X(3)). Fifteen batches were prepared by the slurry method and evaluated for percentage drug entrapment (PDE) and vesicle size. The transformed values of the independent variables and the PDE (dependent variable) were subjected to multiple regression to establish a full-model second-order polynomial equation. F was calculated to confirm the omission of insignificant terms from the full-model equation to derive a reduced-model polynomial equation to predict the PDE of proniosome-derived niosomes. Contour plots were constructed to show the effects of X(1), X(2) and X(3) on the PDE. A model was validated for accurate prediction of the PDE by performing checkpoint analysis. The computer optimization process and contour plots predicted the levels of independent variables X(1), X(2), and X(3) (0, -0.158 and -0.158 respectively), for maximized response of PDE with constraints on vesicle size. The Box-Behnken design demonstrated the role of the derived equation and contour plots in predicting the values of dependent variables for the preparation and optimization of piroxicam proniosomes.

Utility of the Coefficient of Determination (r2) in Assessing the Accuracy of Interspecies Allometric Predictions: Illumination or Illusion?

The appropriateness of relying on the coefficient of determination (r(2)) as a statistical metric for judging the predictability of human clearance (CL) based on interspecies animal data was assessed. An explicit mathematical expression was derived for r(2) as a function of species body weight and the corresponding measured value of CL. The derived mathematical function demonstrated that r(2) is numerically large in most instances. Simulations using random CL generated from a common combination of species of mouse, rat, and monkey resulted in an r(2) of 0.75 as the minimum, and 0.95 and 0.98 at 50th and 75th percentiles, respectively, given that total CL values increase with increasing species body weight. Analysis of literature data also indicated that the prediction accuracy of human CL was not correlated with values of r(2). Therefore, it is concluded that r(2) is a limited statistical measure when assessing allometric scaling for the purpose of predicting human CL.

Immuno-targeting of nonionic surfactant vesicles to inflammation

Niosomes composed of sorbitan monostearate (Span 60), polyoxyethylene sorbitan monostearate (Tween 61), cholesterol, and dicetyl phosphate were conjugated with a purified monoclonal antibody to CD44 (IM7) through a cyanuric chloride (CC) linkage on the polyoxyethylene group of the Tween 61 molecule. Inclusion of small amounts of Tween 61 within the surfactant component of niosomes formed using thin film hydration techniques and sonication did not hamper vesicle stability as compared to Span 60 niosomes. Conjugation was verified by UV absorbance of fluorescently tagged IM7 in non-fluorescing niosomes and fluorescent micrographs. The immuno-niosomes were incubated with synovial lining cells expressing CD44. Attachment of niosomes was evident and showed selectivity and specificity compared to controls. These findings suggest that the resulting immuno-niosomes may provide an effective method for targeted drug delivery.