Design and characterization of clindamycin-loaded nanofiber patches composed of polyvinyl alcohol and tamarind seed gum and fabricated by electrohydrodynamic atomization

In this study, we developed a polymeric nanofiber patch(PNP) for topical disease treatment using electrohydrodynamic atomization(EHDA). The nanofibers were prepared using various concentrations of polyvinyl alcohol(PVA) and tamarind seed gum and loaded with clindamycin HCl as a model drug. The precursor polymer solutions were sprayed using the EHDA technique; the EHDA processing parameters were optimized to obtain blank and drug-loaded PNPs. The skin adherence, translucence, and ventilation properties of the prepared PNPs indicated that they are appropriate for topical application. The conductivity of the polymer solution increased with increasing PVA and clindamycin concentrations, and increasing the PVA concentration enhanced the solution viscosity. Based on scanning electron microscopy analysis, the PVA concentration had a pronounced effect on the morphology of the sprayed product. Nanofibers were fabricated successfully when the solution PVA concentration was 10%, 13%, or 15%(w/v). The applied voltage significantly affected the diameters of the prepared nanofibers, and the minimum nanofiber diameter was 163.86 nm. Differential scanning calorimetry and X-ray diffraction analyses indicated that the modeldrug was dispersed in PVA in an amorphous form. The PNP prepared with a PVA:gum ratio of 9:1 absorbed water better than the PVA-only PNP and the PNP with a PVA:gum ratio of 9.5:0.5. Moreover, the PNPs loaded with clindamycin at concentrations of 1%–3% prohibited the growth of Staphylococcus aureus more effectively than clindamycin gel, a commercially available product.

A new self-emulsifying formulation of mefenamic acid with enhanced drug dissolution

To enhance the dissolution of poorly soluble mefenamic acid,self-emulsifying formulation(SEF),composing of oil,surfactant and co-surfactant,was formulated.Among the oils and surfactants studied,Imwitor■ 742,Tween■ 60,Cremophore■ EL and Transcutol■ HP were selected as they showed maximal solubility to mefenamic acid.The ternary phase diagram was constructed to find optimal concentration that provided the highest drug loading.The droplet size after dispersion and drug dissolution of selected formulations were investigated.The results showed that the formulation containing Imwitor■ 742,Tween■ 60 and Transcutol■ HP(10:30:60)can encapsulate high amount of mefenamic acid.The dissolution study demonstrated that,in the medium containing surfactant,nearly 100% of mefenamic acid were dissolved from SEF within 5 min while 80% of drugs were dissolved from the commercial product in 45 min.In phosphate buffer(without surfactant),80% of drug were dissolved from the developed SEF within 5 min while only about 13% of drug were dissolved in 45 min,from the commercial product.The results suggested that the SEF can enhance the dissolution of poorly soluble drug and has a potential to enhance drug absorption and improve bioavailability of drug.

The effect of surfactant on the physical properties of coconut oil nanoemulsions

The aim of this study was to develop the water compatible form of coconut oil through nanoemulsification. The effect of different types and amounts of surfactants on the physical characteristics of nanoemulsions containing coconut oil was investigated. Coconut oil nanoemulsions containing varied amounts of surfactants including polyethylene glycol octyl phenyl ether(PGO), polyoxyethylene sorbitan monostearate(POS), polyethylene glycol hydrogenated castor oil(PHC), sodium lauryl sulfate(SLS) and poloxamer 407(PLX) were formulated and comparatively evaluated for their physical properties. The results showed that the coconut oil nanoemulsions using PGO, POS and PHC as surfactants exhibited low percent creaming index indicating excellent stability, while those containing SLS and PLX demonstrated the higher percent creaming index suggesting lesser physical stability. The droplet sizes of nanoemulsions consisting of 5%(w/w) PGO, POS and PHC were 22.843, 4.458 and 0.162 μm, respectively. Thus, coconut oil nanoemulsions with the smallest size could be obtained when PHC was applied. Furthermore, the droplet size of nanoemulsions decreased from 33 μm to less than 200 nm with an increase in the amount of PHC from 1% to 10%(w/w). Additionally, the properties of coconut oil based nanoemulsions containing PHC were not changed through temperature cycling test. From these results, it was suggested that the fabrication of stable coconut oil nanoemulsions with small particle size could be easily achieved by using 5%(w/w) PHC as a surfactant. The knowledge gained from the study might provide the basic guideline for the fabrication of stable nanoemulsions for food, cosmetic and pharmaceutical fields in the future.

Design and characterization of monolaurin loaded electrospun shellac nanofibers with antimicrobial activity

The aim of this study was to elucidate the optimized fabrication factors influencing the formation and properties of shellac(SHL) nanofibers loaded with an antimicrobial monolaurin(ML). The main and interaction effects of formulation and process parameters including SHL content(35%–40% w/w), ML content(1%–3% w/w), applied voltage(9–27 kV) and flow rate(0.4–1.2 ml/h) on the characteristic of nanofibers were investigated through a total of 19 experiments based on a full factorial design with three replicated center points. As a result, the SHL content was the major parameter affecting fiber diameter. Another response result revealed that the SHL content would be also the most significant negative impact on amount of beads. An increase in the concentration of SHL leaded to a reduction in the amount of beads. From the results of characterization study, it was proved that ML might be entrapped between the chains of SHL during the electrospinning process exhibiting an excellent encapsulation. According to the response surface area, small(?488 nm) and beadless(?0.48) fibers were obtained with the SHL and ML contents of 37.5% and 1.1% w/w respectively, at the applied voltage of 18 k V and the flow rate of 0.8 ml/h. In addition, the results of the kill-kinetic studies showed that SHL nanofibers loaded with ML exhibited an excellent antibacterial activity against Staphylococcus aureus, while Escherichia coli was less affected due to the hydrophilic structure of the its outer membrane. ML also exerted an antifun-gal activity by reducing the number of Candida albicans colonies. Based on their structural and antimicrobial properties, SHL nanofibers containing ML could be potentially used as a medicated dressing for wound treatment.

Determination of mono-, di-, and trilaurin in modified coconut oil using HPLC–ELSD

Modified coconut oil (MCO) enriched with monolaurin (ML) was prepared by the glycerolysis of coconut oil (1)Glycerolysis converts dilaurin (DL) and trilaurin (TL) into ML, the lauric acid monoglyceride. ML has been found to have antiviral, antibacterial and antifungal activities (2)According to the antimicrobial activity, the glyceride composition of MCO was determined.

Buccal administration of mucoadhesive blend films saturated with propranolol loaded nanoparticles

The aims of this study were to prepare and characterize hydroxypropyl methylcellulose(HPMC)/polycarbophil(PC) mucoadhesive blend films saturated with propranolol hydrochloride(PNL)-loaded nanoparticles to improve permeability of drugs that undergo firstpass metabolism. An ionic cross-linking method and film casting technique was used to prepare nanoparticles and mucoadhesive blend films, respectively. Increasing concentrations of PNL(70, 80, 90 mg/film) in HPMC/PC blend films containing PNL-loaded nanoparticles(PN-films) and HPMC/PC blend films containing PNL(80 mg/film) without nanoparticles(PPfilms) were prepared to test swelling, mucoadhesiveness, release, permeation and physicochemical properties. Scanning electron microscope(SEM) images showed a partially smooth surface with a wrinkled occurrence and spherically shaped, well-dispersed nanoparticles on the surface of PN-films containing PNL 80 mg/film(PN-films-80). The size of the nanoparticles on the surface of PN-films-80 was around 100 nm, which was similar to the nanoparticle size observed using light scattering technique. The swelling index(SI)of all PN-films and PP-films increased greatly in the first period time(10–20 min) and reached swelling equilibrium at 20 min and 30 min, respectively. For the PN-films, the concentration of PNL influenced the mucoadhesive properties and tended to be higher when the amount of PNL increased. Immediate release of all blend film formulations was found in early time points(10–30 min). After 120 min, the release of PN-films-70 was lower than the other PNfilms. Permeation studies using porcine buccal mucosa showed that inclusion of nanoparticles in the films increased the permeability of PNL compared to PP-films. Therefore, buccal administration of mucoadhesive blend films containing PNL-loaded nanoparticles could be a promising approach for drugs that undergo first-pass metabolism.

Formulation and evaluation of gels containing coconut? kernel extract for topical application

The biological activity of coconut( Cocos nucifera L.) extracts from its kernels and various parts was reported by many previous studies, it is therefore believable that the extracts of its kernels might show some activities in topical formulations. Among several kernel extracts, the TC06 extract prepared by soaking the steamed coconut kernels in hot water showed the highest total phenolic content(6.98 ± 0.30 mg GAE/g extract) and the strongest antioxidant activity as determined using FRAP and DPPH methods with a reducing power value of 4.12 ± 0.16 mg AAE/g of extract and an SC 50 value of 2.38 ± 0.14 mg/ml, respectively. In addition, this extract did not display any cytotoxic effects in the concentration range of 50–3200 μg/ml. Meanwhile, it revealed cytoprotective effects against t-BHP-induced cytotoxicity in HaCaT cells at concentrations higher than 400 μg/ml. The results of phytochemical investigations including a chemical color test, TLC, 1 H NMR and FTIR suggested that the TC06 extract was mainly composed of flavonoids and terpenoids. Furthermore, the concentrations of heavy metals including As, Cd, Hg, and Pb in the TC06 extract were below permissible limits. According to the solubility, the TC06 extract was incorporated into gels using Carbopol Ultrez 21 as a gelling agent. The formulated gel containing 3%(w/w) TC06 extract was stable at 4 °C and 25 °C with 75% RH throughout the storage period. It was found that the Carbopol Ultrez 21-based hydroalcoholic gel containing an aqueous extract of coconut kernels exhibited antioxidant activities in the two assays and showed a sufficient consistency, a pleasing color, and a non-oily perception during the period of observation.

Fabrication and characterization of spearmint oil loaded nanoemulsions as cytotoxic agents against oral cancer cell

Spearmint oil(SMO), a commonly used essential oil for oral care products, possesses various interesting functions, especially for anticancer property. However, the application of SMO for cancer treatment is limited due to water insoluble. In the present study, nanoemulsions, which have been widely accepted as dosage forms for poorly water-soluble drugs, were selected as candidate carriers for SMO to inhibit oral cancer cell. The nanoemulsions were fabricated using phase inversion temperature method. The factors affecting formation and properties of nanoemulsions including type and amount of surfactants, oil loading and ratio of SMO to virgin coconut oil(VCO) were investigated. Among the surfactants used, the nanoemulsions containing polyoxyethylene castor oil derivatives(Kolliphor ?EL; PCO35, Cremophor ?RH40; PCO40, Eumulgin ?CO60; PCO60) and polyoxyethylene sorbitan fatty acid esters(PSF80) showed 100% creaming after temperature cycling test indicating excellent physical stability while those containing PCO40 demonstrated more transparency and better physical stability. With an increasing amount of PCO40, the droplet size tended to decrease and was in the nano-size range( < 1000 nm) after increasing to more than 5%(w/w). SMOVCO loading also influenced on the droplet size. At 5%(w/w) PCO40, the maximum SMO-VCO loading of 25%(w/w) to attain nanoemulsions was observed. Moreover, the composition of oils had an impact on size of emulsions. The transparent nanoemulsions were only prepared in the range of SMO-VCO from 40:60 to 80:20, suggesting the optimum ratio of SMO tosurfactant and the composition of oils were the critical factors for formation of nanoemulsions. NMR study disclosed that the interaction between PCO40 with both VCO and SMO should be a possible stabilization mechanism. Furthermore, the SMO-VCO nanoemulsions exhibited significant cytotoxic effect against oral carcinoma(KON) cell line using MTT assay. The finding, therefore, revealed the good feasibility of SMO-VCO nanoemulsions as novel carriers for treating of oral cancer.

Dissolution improvement by solid dispersions composed of nifedipine, Eudragit?E and silica from rice husk

Nifedipine is a practically water-insoluble drug used therapeutically as a calcium-channel blocker for systemic and coronary vasodilation.Poorly soluble drugs that undergo dissolution rate-limited gastrointestinal absorption generally show increased bioavailability when dissolution is improved by formulation techniques[1].In solid dispersion system,a drug may exist as an amorphous form in polymeric carriers,and this may result in improved solubility and dissolution rate as compared with crystalline drug.Solid dispersion can be prepared by either fusion or solvent method[2].

Factors affecting formation of nanoemulsions containing modified coconut oil and spearmint oil

Dental caries is one of the major oral health problems in most countries,affecting more than 50%of school children and majority of adults.Normally,we can prevent the disease by utilization of suitable antiseptics,e.g.alcohols and chlorhexidine[1].However,most antiseptics cause irritation or straining of the mucous membrane and teeth.Therefore,finding a more safe and efficient antiseptics is still a matter of interest to eradicate the causative pathogen.Volatile oils from plants including spearmint oil(SMO)could reduce the number of Streptococcus mutans counts in plaques and saliva.

Development and characterization of nifedipine-amino methacrylate copolymer solid dispersion powders with various adsorbents

Solid dispersions of nifedipine(NDP), a poorly water-soluble drug, and amino methacrylate copolymer(AMCP) with aid of adsorbent, that is, fumed silica, talcum, calcium carbonate,titanium dioxide, and mesoporous silica from rice husks(SRH), were prepared by solvent method. The physicochemical properties of solid dispersions, compared to their physical mixtures, were determined using powder X-ray diffractometry(PXRD) and differential scanning calorimetry(DSC). The surface morphology of the prepared solid dispersions was examined by scanning electron microscopy(SEM). The dissolution of NDP from solid dispersions was compared to NDP powders. The effect of adsorbent type on NDP dissolution was also examined. The dissolution of NDP increased with the ratio of NDP:AMCP:adsorbent of 1:4:1 when compared to the other formulations. As indicated from PXRD patterns, DSC thermograms and SEM images, NDP was molecularly dispersed within polymer carrier or in an amorphous form, which confirmed the better dissolution of solid dispersions. Solid dispersions containing SRH provided the highest NDP dissolution, due to a porous nature of SRH, allowing dissolved drug to fill in the pores and consequently dissolve in the medium.The results suggested that solid dispersions containing adsorbents(SRH in particular) demonstrated improved dissolution of poorly water-soluble drug when compared to NDP powder.

Preface: Special issue for the “Asian Federation for Pharmaceutical Sciences(AFPS)2015 Conference”

We are pleased to present this special issue for the“Asian Federation for Pharmaceutical Sciences(AFPS)2015 Conference”of the Asian Journal of Pharmaceutical Sciences.The abstracts included in this issue are from those presented as lectures and posters at the Asian Federation for Pharmaceutical Sciences(AFPS)2015 Conference held in Bangkok,Thailand,during 25–27 November 2015.This was the latest in the well-established AFPS series of international conferences,which are organized in alternate years in different Asian countries to provide a forum for the presentation and discussion of recent progress in the field of pharmaceutical sciences.