Determination of Mycoplasma hyopneumoniae-Specific IgG, IgG1, and IgG2a Titers in BALB/c Mice Induced by Mineral Oil-Based Oil-in-Water Emulsion Adjuvants Prepared Using a Self-Emulsifying Drug Delivery System.

We prepared mineral oil-based emulsion adjuvants by employing simple self-emulsifying drug delivery system (SEDDS). Mineral oil emulsions (3%, 5%, and 7%) were prepared using deionized water and C-971P NF and C-940 grade carbomer solutions with concentrations 0.01% (w/v) and 0.02% (w/v). In total, 15 emulsions were prepared and mixed with a solution containing inactivated Mycoplasma hyopneumoniae (J101 strain) antigen and porcine circovirus type 2 antigen to prepare vaccines. Droplet sizes in the submicron range and zeta potential values between - 40 and 0 mV were maintained by most emulsion adjuvants for a period of 6 months. Emulsion adjuvants were regarded safe, and their M. hyopneumoniae-specific IgG, IgG1, and IgG2a titers were either better or comparable to those of aluminum gel.

Strategic approaches for enhancement of in vivo transbuccal peptide drug delivery in rabbits using iontophoresis and chemical enhancers.

PURPOSE: To evaluate the feasibility of iontophoresis and the combination effects with chemical enhancers on in vivo hypocalcemic effect of transbuccally delivered salmon calcitonin (sCT). METHODS: N-acetyl-L-cysteine (NAC), sodium deoxyglycocholate (SDGC), and ethanol were used as chemical enhancers; and 0.5 mA/cm(2) fixed electric current was employed as a physical enhancer. sCT hydrogel was applied to rabbit buccal mucosa, and blood samples were obtained via the central auricular artery. Blood calcium level was measured by calcium kit and the conformational changes of buccal mucosa were investigated with FT-IR spectroscopy. Hematoxylin/eosin staining was used for the histological evaluation of buccal mucosa. RESULTS: Iontophoresis groups except iontophoresis-NAC group showed significant hypocalcemic effect compared to negative control, in particular iontophoresis-SDGC combination group showed fast onset of action as well as sustained hypocalcemic effect (p < 0.05). FT-IR result demonstrated the reduction of buccal barrier function, and the histological study showed a decrease in buccal thickness as well as minor damage to the dermal-epidermal junctions in the enhancing method groups; however, the damaged tissues virtually recovered within 24 h after the removal of electrodes. CONCLUSIONS: Iontophoresis and combination with SDGC were found to be safe and potential strategies for transbuccal peptide delivery in vivo.

EGF, a veteran of wound healing: highlights on its mode of action, clinical applications with focus on wound treatment, and recent drug delivery strategies.

Epidermal growth factor (EGF) has been used in wound management and regenerative medicine since the late 1980s. It has been widely utilized for a long time and still is because of its excellent tolerability and efficacy. EGF has many applications in tissue engineering, cancer therapy, lung diseases, gastric ulcers, and wound healing. Nevertheless, its in vivo and during storage stability is a primary concern. This review focuses on the topical use of EGF, especially in chronic wound healing, the emerging use of biomaterials to deliver it, and future research possibilities. To successfully deliver EGF to wounds, a delivery system that is proteolytically resistant and stable over the long term is required. Biomaterials are an area of interest for the development of such systems. These systems may be used in non-healing wounds such as diabetic foot ulcers, pressure ulcers, and burns. In these pathologies, EGF can reduce the risk of amputation of the lower extremities, as it accelerates the wound healing process. Furthermore, appropriate delivery system would also stabilize and control the EGF release profile in a wound. Several in vitro and in vivo studies have already proven the efficacy of such systems in the above-mentioned types of wounds. Moreover, several formulations such as ointments and intralesional injections are already available on the market. However, these products are still problematic in terms of inadequate diffusion of EGF, low bioavailability storage conditions, and shelf-life. This review discusses the nano formulations comprising biomaterials infused with EGF which could be a promising delivery system for chronic wound healing in the future.

Enhanced percutaneous delivery of recombinant human epidermal growth factor employing nano-liposome system.

We encapsulated recombinant human epidermal growth factor (rhEGF) into nano-liposomes (NLs) system for topical delivery. The rhEGF-loaded NLs were prepared using a high pressure homogenization method. Morphology and overall particle distribution of NLs were investigated using transmission electron microscopy (TEM) and high resolution microscope (CytoViva™). Particle size, zeta (ζ) potential and encapsulation efficiency were measured and the percutaneous delivery of NLs was evaluated using Franz diffusion cells and immunofluorescence confocal laser scanning microscopy (CLSM). The mean particle size, zeta potential and encapsulation efficiency of the NLs were 155.57 ± 2.59 nm, -57.92 ± 4.35 mV and 9.00 ± 0.39%, respectively. TEM and microscopic analysis showed spherical, very even-sized vesicles approximately 150 nm. The skin permeation and localization of rhEGF were enhanced by NLs. CLSM image analysis provided that the NLs enhanced the permeation and localization of rhEGF in rat skin by facilitating entry through pores of skin.

Examination of Effective Buccal Absorption of Salmon Calcitonin Using Cell-Penetrating Peptide-Conjugated Liposomal Drug Delivery System.

INTRODUCTION: The buccal route has been considered an attractive alternative delivery route for injectable formulations. Cell-penetrating peptides (CPPs) are gaining increased attention for their cellular uptake and tissue permeation effects. This study was aimed to evaluate the in vitro and ex vivo permeation-enhancing effect of penetratin-conjugated liposomes for salmon calcitonin (sCT) in TR146 human buccal cells and porcine buccal tissues. METHODS: Penetratin was conjugated to phospholipids through a maleimide-thiol reaction. Liposomes were prepared and sCT was encapsulated using a thin-film hydration method. Physical properties such as particle size, zeta potential, encapsulation efficiency, and morphological images via transmission electron microscopy were obtained. Cellular uptake studies were conducted using flow cytometry (FACS) and confocal laser scanning microscopy (CLSM). A cell permeation study was performed using a Transwell® assay, and permeation through porcine buccal tissue was evaluated. The amount of sCT permeated was quantified using an ELISA kit and was optically observed using CLSM. RESULTS: The particle size of penetratin-conjugated liposomes was approximately 123.0 nm, their zeta potential was +29.6 mV, and their calcitonin encapsulation efficiency was 18.0%. In the cellular uptake study using FACS and CLSM, stronger fluorescence was observed in penetratin-conjugated liposomes compared with the solution containing free sCT and control liposomes. Likewise, the amount of sCT permeated from penetratin-conjugated liposomes was higher than that from the free sCT solution and control liposomes by 5.8-fold across TR146 cells and 91.5-fold across porcine buccal tissues. CONCLUSION: Penetratin-conjugated liposomes are considered a good drug delivery strategy for sCT via the buccal route.

Enhancing solubility and bioavailability of coenzyme Q10: formulation of solid dispersions using Soluplus® as a carrier.

Improving the aqueous solubility of poorly soluble compounds have been a major issue in the pharmaceutical industry. In the present study, binary amorphous solid dispersions (SDs) of Coenzyme Q10 (CoQ10), a biopharmaceutics classification system (BCS) II compound and Soluplus® were prepared to enhance the solubility and pharmacokinetic properties compared to crystalline CoQ10. SDs were prepared with different ratios of CoQ10 and Soluplus® (1:3, 1:5, and 1:7) using spray drying technology, and the physicochemical properties of the SDs were evaluated. X-ray powder diffraction, differential scanning calorimetry, and scanning electron microscopy suggested the conversion of the crystalline form of CoQ10 to a binary amorphous system in the SDs. Fourier transform infrared spectroscopy revealed no potential interactions between CoQ10 and Soluplus®. The solubility of the optimal SD formulation (SD 1:7) was approximately 9000-fold higher than that of crystalline CoQ10, and the increment was Soluplus® concentration dependent. As a result, optimized SD 1:7 also showed significantly enhanced dissolution rate where maximum drug release was observed within 30 min in two different dissolution media. Moreover, in contrast to crystalline CoQ10, CoQ10 SDs showed improved pharmacokinetic parameters. Thus, the SD 1:7 formulation is expected to improve biopharmaceutical properties and therapeutic efficacy of CoQ10.

Optimized self-microemulsifying drug delivery system improves the oral bioavailability and brain delivery of coenzyme Q10.

Our study aimed to develop a self-microemulsifying drug delivery system for the poorly aqueous-soluble drug Coenzyme Q10, to improve the dissolution and the oral bioavailability. Excipients were selected based on their Coenzyme Q10 solubility, and their concentrations were set for the optimization of the microemulsion by using a D-optimal mixture design to achieve a minimum droplet size and a maximum solubility of Coenzyme Q10 within 15 min. The optimized formulation was composed of an oil (omega-3; 38.55%), a co-surfactant (Lauroglycol® 90; 31.42%), and a surfactant (Gelucire® 44/14; 30%) and exhibited a mean droplet size of 237.6 ± 5.8 nm and a drug solubilization (at 15 min) of 16 ± 2.48%. The drug dissolution of the optimized formulation conducted over 8 h in phosphate buffer medium (pH 6.8) was significantly higher when compared to that of the Coenzyme Q10 suspension. A pharmacokinetic study in rats revealed a 4.5-fold and a 4.1-fold increase in the area under curve and the peak plasma concentration values generated by the optimized formulation respectively, as compared to the Coenzyme Q10 suspension. A Coenzyme Q10 brain distribution study revealed a higher Coenzyme Q10 distribution in the brains of rats treated with the optimized formulation than the Coenzyme Q10 suspension. Coenzyme Q10-loaded self microemulsifying drug delivery system was successfully formulated and optimized by a response surface methodology based on a D-optimal mixture design and could be used as a delivery vehicle for the enhancement of the oral bioavailability and brain distribution of poorly soluble drugs such as Coenzyme Q10.

Bile acid transporter-mediated oral absorption of insulin via hydrophobic ion-pairing approach.

Despite many ongoing and innovative approaches, there are still formidable challenges in the clinical translation of oral peptide drugs into marketable products due to their low absorption and poor bioavailability. Herein, a novel nanocarrier platform was developed that employs a hydrophobic ion-pairing (HIP) of model peptide (insulin) and the anionic bile salt (sodium glycodeoxycholate, SGDC), and markedly improves intestinal absorption via the bile acid pathway. The developed HIP-nanocomplexes (C1 and C2) were optimized, characterized, and in vitro and in vivo evaluation were performed to assess oral efficacy of these system. The optimal molar ratios of C1 and C2-nanocomplexes were 30:1 and 6:1 (SGDC:insulin), respectively. Compared to the insulin solution, the C1 and C2 nanocomplexes significantly enhanced the permeation of insulin across the Caco-2 cell monolayers, with 6.36- and 4.05-fold increases in apparent permeability, respectively. Uptake mechanism studies were conducted using different endocytosis inhibitors and apical sodium-dependent bile acid transporter (ASBT)-transfected MDCK cells, which demonstrated the involvement of the energy-dependent ASBT-mediated active transport. Furthermore, the intrajejunal administration of C1 and C2 resulted in their pharmacological availabilities (PA) being 6.44% and 0.10%, respectively, indicating increased potential for C1, when compared to C2. Similarly, the PA and the relative bioavailability with intrajejunal administration of the C1 were 17.89-fold and 16.82-fold greater than those with intracolonic administration, respectively, confirming better jejunal absorption of C1. Overall, these findings indicate that the HIP-nanocomplexes could be a prominent platform for the effective delivery of peptides with improved intestinal absorption.

Development, Characterization, and Ex Vivo Assessment of Elastic Liposomes for Enhancing the Buccal Delivery of Insulin.

Buccal drug delivery is a suitable alternative to invasive routes of drug administration. The buccal administration of insulin for the management of diabetes has received substantial attention worldwide. The main aim of this study was to develop and characterize elastic liposomes and assess their permeability across porcine buccal tissues. Sodium-cholate-incorporated elastic liposomes (SC-EL) and sodium-glycodeoxycholate-incorporated elastic liposomes (SGDC-EL) were prepared using the thin-film hydration method. The prepared liposomes were characterized and their ex vivo permeability attributes were investigated. The distribution of the SC-EL and SGDC-EL across porcine buccal tissues was evaluated using confocal laser scanning microscopy (CLSM). The SGDC-EL were the most superior nanocarriers since they significantly enhanced the permeation of insulin across porcine buccal tissues, displaying a 4.33-fold increase in the permeability coefficient compared with the insulin solution. Compared with the SC-EL, the SGDC-EL were better at facilitating insulin permeability, with a 3.70-fold increase in the permeability coefficient across porcine buccal tissue. These findings were further corroborated based on bioimaging analysis using CLSM. SGDC-ELs showed the greatest fluorescence intensity in buccal tissues, as evidenced by the greater shift of fluorescence intensity toward the inner buccal tissue over time. The fluorescence intensity ranked as follows: SGDC-EL > SC-EL > FITC-insulin solution. Conclusively, this study highlighted the potential nanocarriers for enhancing the buccal permeability of insulin.

Facilitated Buccal Insulin Delivery via Hydrophobic Ion-Pairing Approach: In vitro and ex vivo Evaluation.

BACKGROUND: The clinical use of therapeutic peptides has been limited because of their inefficient delivery approaches and, therefore, inadequate delivery to target sites. Buccal administration of therapeutic peptides offers patients a potential alternative to the current invasive routes of administration. PURPOSE: The aim of the study was to fabricate hydrophobic ion-pairing (HIP)-nanocomplexes (C1 and C2) utilizing anionic bile salts and cationic peptides, and to assess their permeability across TR146 buccal cell layers and porcine buccal tissue. METHODS: C1 and C2-nanocomplexes were fabricated using the HIP approach. In addition, their physiochemical and morphological attributes, in vitro and ex vivo permeability properties, and qualitative and quantitative cellular uptake were evaluated and compared. The localization of C1 and C2-nanocomplexes in porcine buccal tissue was determined using confocal laser scanning microscopy. RESULTS: The C1-nanocomplex was the superior nanocarrier and significantly enhanced the transport of insulin across TR146 cell layers and porcine buccal tissue, exhibiting a 3.00- and 51.76-fold increase in permeability coefficient, respectively, when compared with insulin solution (p < 0.01). C1-nanocomplex was more efficient than C2-nanocomplex at facilitating insulin permeability, with a 2.18- and 27.64-fold increase across TR146 cell layers and porcine buccal tissue, respectively. The C1-nanocomplex demonstrated immense uptake and localization of insulin in TR146 cells and porcine buccal tissue, as evidenced by a highly intense fluorescence in TR146 cells, and a great shift of fluorescence intensity towards the inner region of buccal tissue over time. The increase in fluorescence intensity was observed in the order of C1 > C2 > insulin solution. CONCLUSION: In this study, we highlighted the efficacy of potential nanocarriers in addressing the daunting issues associated with the invasive administration of insulin and indicated a promising strategy for the buccal administration and delivery of this life-saving peptide hormone.

In Vitro and Ex Vivo Evaluation of Penetratin as a Non-invasive Permeation Enhancer in the Penetration of Salmon Calcitonin through TR146 Buccal Cells and Porcine Buccal Tissues.

Buccal tissues are considered one of the potential alternative delivery route because of fast drug absorption and onset of action due to high vascularization and a non-keratinized epithelial membrane. In this study, the effect of Penetratin on the permeation of salmon calcitonin (sCT), a model macromolecular peptide drug, through TR146 buccal cells and porcine buccal tissues has been evaluated. To observe permeation profile of sCT, TR146 buccal cells were treated with Alexa 647 conjugated sCT (Alexa 647-sCT) with different concentrations of fluorescein isothiocyanate -labeled Penetratin (FITC-Penetratin) ranging from 0 to 40 µM, and analyzed using flow cytometry and confocal laser scanning microscopy. Intracellular penetration of FITC-Penetratin rapidly increased at low concentrations from 0 to 15 µM and it gradually increased at concentrations above 15 µM. Intracellular penetration of Alexa 647-sCT enhanced with the increase of FITC-Penetratin concentration. When TR146 cell layers and buccal tissues were co-treated with sCT and Penetratin as permeation enhancer, the flux of sCT increased as per Penetratin concentration. Compared to the control, 12.2 µM of Penetratin enhanced the flux of sCT in TR146 cell layers and buccal tissues by 5.5-fold and 93.7-fold, respectively. These results strongly suggest that Penetratin may successfully act as a non-invasive permeation enhancer for macromolecular peptide drug delivery through buccal routes.

Modulation of elastin exon 26A mRNA and protein expression in human skin in vivo.

Photoaged skin contains elastotic materials in the upper reticular dermis, a result of a commonly known as solar elastosis. It is known that the primary transcript of elastin undergoes extensive alternative splicing and that this results in the translation of multiple heterogeneous protein isoforms. In this study, we found that UV irradiation and heat treatment increased the levels of elastin transcript containing exon 26A and its encoded elastin isoform in the epidermis of human skin in vivo and in cultured human keratinocytes in vitro. We also found that the elastin transcript containing exon 26A was upregulated in photoaged forearm skin compared with intrinsically aged buttock skin in the same elderly individuals. We observed that topical retinoic acid treatment to human skin did not increase the expression of exon 26A mRNA, but that tropoelastin mRNA expression was increased by this treatment. These findings suggest that the production of the elastin isoform containing exon 26A peptide is increased by UV exposure and heat treatment in human skin in vivo and that it may play an important role in the development of solar elastosis in photoaged human skin.

Effects of infrared radiation and heat on human skin aging in vivo.

Sunlight damages human skin, resulting in a wrinkled appearance. Since natural sunlight is polychromatic, its ultimate effects on the human skin are the result of not only the action of each wavelength separately, but also interactions among the many wavelengths, including UV, visible light, and infrared (IR). In direct sunlight, the temperature of human skin rises to about 40 degrees C following the conversion of absorbed IR into heat. So far, our knowledge of the effects of IR radiation or heat on skin aging is limited. Recent work demonstrates that IR and heat exposure each induces cutaneous angiogenesis and inflammatory cellular infiltration, disrupts the dermal extracellular matrix by inducing matrix metalloproteinases, and alters dermal structural proteins, thereby adding to premature skin aging. This review provides a summary of current research on the effects of IR radiation and heat on aging in human skin in vivo.Journal of Investigative Dermatology Symposium Proceedings (2009) 14, 15-19; doi:10.1038/jidsymp.2009.7.

Caveolin-1 increases basal and TGF-beta1-induced expression of type I procollagen through PI-3 kinase/Akt/mTOR pathway in human dermal fibroblasts.

Caveolin-1 (Cav-1) is a major structural protein of caveolae and plays an important role as a negative regulator of various signaling pathways such as the transforming growth factor-beta (TGF-beta)/smad pathway. In this study, we investigated the role of cav-1 on basal and TGF-beta1-induced expression of type I procollagen in human dermal fibroblasts. Our results demonstrated that basal and TGF-beta1-induced expression of type I procollagen were significantly increased by adenoviral cav-1 (Ad-cav-1) overexpression, while the basal level of type I procollagen was decreased by cav-1 siRNA. Overexpression of cav-1 inhibited TGF-beta1-induced phosphorylation of smad3 and transcription of 3TP-Lux and SBE luciferase reporters, suggesting that cav-1 may inhibit the TGF-beta1/smad signaling pathway. We observed that TGF-beta1-induced type I procollagen expression was decreased by smad3 siRNA transfection. However, the reduction of TGF-beta1-induced type I procollagen expression by smad3 siRNA was reversed by cav-1 overexpression. In addition, our results also showed that TGF-beta1 treatment increased the phosphorylation of Akt, and Ad-cav-1 infection augmented this TGF-beta1-induced phosphorylation of Akt. Ad-myr-Akt infection significantly increased the basal expression of type I procollagen. In contrast, TGF-beta1-induced type I procollagen expression was decreased by Akt siRNA transfection and the PI3-kinase inhibitor, LY294002, inhibited the TGF-beta1-induced type I procollagen expression and also inhibited the cav-1-induced expression of type I procollagen. In conclusion, our results suggest that cav-1 increases the basal and TGF-beta1-induced expression of type I procollagen by regulating two opposite signaling pathways: inhibiting TGF-beta1/smad signaling and activating a PI-3 kinase/Akt/mTOR-dependent pathway in human dermal fibroblasts, ultimately resulting in increased type I procollagen expression.

Preparation of Squalene Oil-Based Emulsion Adjuvants Employing a Self-Emulsifying Drug Delivery System and Assessment of Mycoplasma hyopneumoniae-Specific Antibody Titers in BALB/c Mice.

In this study, a self-emulsifying drug delivery system (SEDDS) was employed to prepare novel squalene oil-based emulsion adjuvants. Deionized water, 0.01% and 0.02% (w/v) carbomer solutions of C-971P NF and C-940 grades were used to prepare emulsions containing 3%, 5% and 10% of squalene oil. Altogether 15 candidate emulsions were prepared and used as adjuvants for the delivery of a combination vaccine containing a porcine circovirus type 2 (PCV2) antigen and inactivated Mycoplasma hyopneumoniae (J101 strain) antigen. Most of the emulsions showed droplet sizes in the submicron range and maintained zeta potential values between -40 mV to 0 mV for six months, indicating good physical stability as a vaccine adjuvant. Emulsion-based candidate adjuvants prepared with SEDDS technology stimulated IgG, IgG1 and IgG2a like a currently commercially available adjuvant, Montanide ISATM 201, and they were safe and their Mycoplasma hyopneumoniae-specific antibody titers were considered as comparable with that of Montanide ISATM 201.

Complex formulations, simple techniques: Can 3D printing technology be the Midas touch in pharmaceutical industry?

3D printing is a method of rapid prototyping and manufacturing in which materials are deposited onto one another in layers to produce a three-dimensional object. Although 3D printing was developed in the 1980s and the technology has found widespread industrial applications for production from automotive parts to machine tools, its application in pharmaceutical area is still limited. However, the potential of 3D printing in the pharmaceutical industry is now being recognized. The ability of 3D printing to produce medications to exact specifications tailored to the needs of individual patients has indicated the possibility of developing personalized medicines. The technology allows dosage forms to be precisely printed in various shapes, sizes and textures that are difficult to produce using traditional techniques. However, there are various challenges associated with the proper application of 3D printing in the pharmaceutical sector which should be overcome to exploit the scope of this technology. In this review, an overview is provided on the various 3D printing technologies used in fabrication of complex dosage forms along with their feasibility and limitations.

Reactive oxygen species produced by NADPH oxidase, xanthine oxidase, and mitochondrial electron transport system mediate heat shock-induced MMP-1 and MMP-9 expression.

In addition to ultraviolet radiation, human skin is also exposed to infrared radiation (IR) from natural sunlight. IR typically increases the skin temperature. This study examined whether or not heat shock-induced ROS stimulates MMPs in keratinocyte HaCaT cells. In HaCaT cells, heat shock was found to increase the intracellular ROS levels, including hydrogen peroxide and superoxide. The heat shock treatment induced MMP-1 and MMP-9, but not MMP-2, at the mRNA and protein levels. Moreover, heat shock caused the rapid activation of the three distinct MAPKs, ERK, JNK, and p38 kinase. The heat shock-induced expression of MMP-1 and MMP-9 was significantly suppressed by a pretreatment with the antioxidant NAC or catalase. On the other hand, SOD inhibited heat shock-induced activity of MMP-9 induction, but not MMP-1. A pretreatment with NAC or catalase, but not SOD, attenuated the phosphorylation of ERK, JNK, and p38 kinase by heat shock. The potential sites of ROS generation by heat shock along with its role in the heat shock-induced expression of MMP-1 and MMP-9 were next analyzed. These results indicate that heat shock-induced ROS is promoted via NADPH oxidase, xanthine oxidase, and mitochondria. Indeed, the NADPH oxidase and xanthine oxidase activities were increased by heat shock. Overall, the ROS produced by heat shock may play an important role in the heat shock-induced activation of MAPKs, which can induce MMP-1 and-9 expressions.

Facilitated permeation of insulin across TR146 cells by cholic acid derivatives-modified elastic bilosomes.

BACKGROUND: Buccal delivery of insulin is still a challenging issue for the researchers due to the presence of permeability barrier (buccal mucosa) in the buccal cavity. The main objective of this study was to investigate the safety, effectiveness, and potential of various liposomes containing different bile salts to improve the permeation of insulin across in vitro TR146 buccal cell layers. METHODS: Elastic bilosomes containing soy lecithin and bile salt edge activators (sodium cholate [SC], sodium taurocholate [STC], sodium glycocholate [SGC], sodium deoxyglycocholate [SDGC], or sodium deoxytaurocholate [SDTC]) were fabricated by thin-film hydration method. The prepared liposomes were characterized, and in vitro permeation studies were performed. The fluorescein isothiocyanate-insulin-loaded elastic bilosomes were used to evaluate the quantitative and qualitative cellular uptake studies. RESULTS: The prepared elastic bilosomes had a particle size and an entrapment efficiency of ~140-150 nm and 66%-78%, respectively. SDGC-lipo (SDGC-incorporated liposome) was observed to be the most superior with an enhancement ratio (ER) of 5.24 (P<0.001). The SC-incorporated liposome (SC-lipo) and SDTC-incorporated liposome (SDTC-lipo) also led to a significant enhancement with ERs of 3.20 and 3.10 (P<0.05), respectively, compared with insulin solution. These results were further supported by quantitative and qualitative cellular uptake studies performed employing fluorescence-activated cell sorting analysis and confocal microscopy, respectively. The relative median fluorescence intensity values of elastic bilosomes were counted in the order of SDGC-lipo > SC-lipo > SDTC-lipo > SGC-incorporated liposome > STC-incorporated liposome, and similarity in the permeability profile of the employed elastic bilosomes was noted. CONCLUSION: This study presents the employment of various derivatives of cholic acid-loaded elastic bilosomes as a promising strategy to enhance the permeation of insulin through buccal route.

Iontophoretic Transdermal Delivery of Human Growth Hormone (hGH) and the Combination Effect of a New Type Microneedle, Tappy Tok Tok®.

Transdermal drug administration presents several advantages and it is therefore favorable as an alternative drug delivery route. However, transdermal delivery of biopharmaceutical drugs is made difficult by the skin barrier. Microneedle application and iontophoresis are strategies which can be used to overcome this barrier. Therefore, recombinant human growth hormone (rhGH) was used as a model macromolecular drug and was transdermally delivered using microneedle application and iontophoresis. Methylene blue staining, stereomicroscopy and scanning electron microscope (SEM) imaging were used to characterize the microchannels produced. To optimize the iontophoresis protocol, the effects of molecular charge and current density on transdermal delivery were evaluated in an in vitro permeation study using excised rat skin tissues. Using the optimized iontophoresis protocol, the combination effects of iontophoretic delivery via microchannels were evaluated in three different experimental designs. The flux obtained with anodal iontophoresis in citrate buffer was approximately 10-fold higher that that with cathodal iontophoresis in phosphate buffered saline (PBS). Flux also increased with current density in anodal iontophoresis. The combination of iontophoresis and microneedle application produced higher flux than single application. These results suggest that anodal iontophoresis with higher current density enhances the permeation of macromolecules through microchannels created by microneedles. In conclusion, the combination of iontophoresis and microneedles is a potential strategy for the enhancement of transdermal delivery of macromolecular drugs.

Development and Evaluation of a Water Soluble Fluorometholone Eye Drop Formulation Employing Polymeric Micelle.

Low aqueous solubility of drug causes difficulties in preparation and inconvenience of administration. Polymeric micelles of fluorometholone (FML) using solid dispersion technique were prepared to develop an eye drop formulation with enhanced water solubility. Solid dispersions of FML were prepared at various FML:Soluplus® w/w ratios using solvent evaporation method. A physical mixture was also prepared. Physicochemical characterization was performed with various methods. Ex vivo porcine corneal permeation of polymeric micelle, physical mixture, and commercial product were compared. FML solid dispersion (1:15) showed the highest solubility, which was c.a. 169.6- and 15.3-fold higher than that of pure FML and physical mixture. Characterization showed that the crystalline form of FML changed to amorphous state and polymeric micelles were formed in round micelle. Flucon®, a commercial product of FML, showed significantly large particle size and high poly dispersity index. In contrast, FML polymeric micelle showed submicron size with uniform size distribution. Ex vivo porcine corneal permeation study showed that permeation by polymeric micelles was significantly higher than that by the commercial product and physical mixture. In addition, confocal laser scanning microscopic analysis supported the enhanced porcine corneal tissue permeation property of polymeric micelle. In conclusion, polymeric micelle prepared with solid dispersion using Soluplus® can be a potential nanomedicine for ocular delivery of poorly water-soluble FML.