International Journal of Pharmaceutics

Publisher: Elsevier

Journal description

The International Journal of Pharmaceutics provides a medium for the publication of innovative papers, reviews, mini-reviews, short communications and notes dealing with physical, chemical, biological, microbiological and engineering studies related to the conception, design, production, characterisation and evaluation of drug delivery systems in vitro and in vivo. "Drug" is defined as any therapeutic or diagnostic entity, including oligonucleotides, gene constructs and radiopharmaceuticals. Areas of particular interest include: physical pharmacy; polymer chemistry and physical chemistry as applied to pharmaceutics; excipient function and characterisation; biopharmaceutics; absorption mechanisms; membrane function and transport; novel routes and modes of delivery; responsive delivery systems, feedback and control mechanisms including biosensors; applications of cell and molecular biology to drug delivery; prodrug design; bioadhesion (carrier-ligand interactions); and biotechnology (protein and peptide delivery). Editorial Policy The over-riding criteria for publication are originality, high scientific quality and interest to a multidisciplinary audience. Papers not sufficiently substantiated by experimental detail will not be published. Any technical queries will be referred back to the author, although the Editors reserve the right to make alterations in the text without altering the technical content. Manuscripts submitted under multiple authorship are reviewed on the assumption that all listed authors concur with the submission and that a copy of the final manuscript has been approved by all authors and tacitly or explicitly by the responsible authorities in the laboratories where the work was carried out. If accepted, the manuscript shall not be published elsewhere in the same form, in either the same or another language, without the consent of the Editors and Publisher. Authors must state in a covering letter when submitting papers for publication the novelty embodied in their work or in the approach taken in their research. Routine bioequivalence studies are unlikely to find favour. No paper will be published which does not disclose fully the nature of the formulation used or details of materials which are key to the performance of a product, drug or excipient. Work which is predictable in outcome, for example the inclusion of another drug in a cyclodextrin to yield enhanced dissolution, will not be published unless it provides new insight into fundamental principles.

Current impact factor: 3.99

Impact Factor Rankings

Additional details

5-year impact 3.27
Cited half-life 7.10
Immediacy index 0.51
Eigenfactor 0.04
Article influence 0.71
Website International Journal of Pharmaceutics website
ISSN 1873-3476

Publisher details


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    • NIH Authors articles will be submitted to PubMed Central after 12 months
    • Publisher last contacted on 18/10/2013
  • Classification
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Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this work is to study the digestibility of PEG-30-di-(polyhydroxystearate) (Cithrol® DPHS) and its semisolid novel self-nanoemulsifying drug delivery systems (SNEDDS). Furthermore, the SNEDDS-mediated solubility enhancement of the poorly water-soluble drug Progesterone was evaluated in different media. Additionally, the impact of digestion on Progesterone solubilization was investigated in vitro by a pancreatin digestion assay. The Progesterone-loaded semisolid self-nanoemulsifying formulation (F2) was comprehensively characterized by photon correlation spectroscopy (PCS), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR). SNEDDS were able to enhance the equilibrium solubility of Progesterone at various media. Only a minor part of Cithrol® DPHS was digested by pancreatin (less than 6%). Furthermore, protection of Progesterone against digestion-mediated precipitation was observed. Therefore, DPHS containing SNEDDS are attractive candidates for the development of bio robust drug delivery systems for the oral delivery of poorly soluble drugs.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.044
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    ABSTRACT: Dissolution is invariably identified as a critical quality attribute for oral solid dosage forms, since it is related to when a drug is available for absorption and ultimately exert its effect. In this paper, the influence of granule and compression variability introduced by a design of experiments on the entire dissolution profile was studied with an innovative multivariate tool: bi-directional projections to orthogonal structures (O2PLS). This method enabled a more holistic process understanding compared to conventional approaches where only a single response is used to quantify dissolution. The O2PLS analysis of tablet manufacturing data showed that the disintegration phase of dissolution (10-15minutes) was controlled by granule attributes and tablet hardness, while the later phase (15-30minutes) was solely controlled by granule attributes. The bidirectional nature of the O2PLS model made it more fit for exploratory purposes, but decreased predictive ability. This approach does not require prior knowledge on the dissolution mechanism and is therefore particularly suited for exploratory studies gaining process understanding during early phase development. The outcome can then guide the selection of attributes, parameters and their ranges for the development of predictive models, e.g. models to define a suitable design space for the process. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.040
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    ABSTRACT: Propofol (2,6-diisopropylphenol) is a safe and widely used anesthetic, but due to low water solubility and high lipophilicity a difficult compound to formulate. The solubility of propofol in the semifluorinated alkane Perfluorohexyloctane (F6H8) is very high (>300mg/ml). In the present work we investigate if a F6H8-based emulsion could be used as a new intravenous drug delivery system for propofol from a pharmacokinetic, pharmacodynamic and safety point of view. The pharmacokinetic parameters were evaluated after an intravenous bolus injection of either Disoprivan(®) or a F6H8-based propofol emulsion in Wistar rats. The onset and end of sedation after multiple dosings (5, 10 and 15mg/kg bw) was examined. Clinical chemistry and histology were assessed. No significant difference was found for any of the pharmacokinetic parameters. No differences in the onset nor the end of sedation in the tested dosages could be detected. Histology scores revealed no differences. A slightly increased alanine aminotransferase (ALT) was measured after multiple application of the F6H8-propofol emulsion. In conclusion, the F6H8-propofol emulsion showed no significant different pharmacokinetics and sedation properties, compared to a commercial soy-based propofol emulsion. Further, no toxic effects could be detected on the F6H8 emulsion indicating it was a safe excipient in rats. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.037
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    ABSTRACT: The cost of 3D printing has reduced dramatically over the last few years and is now within reach of many scientific laboratories. This work presents an example of how 3D printing can be applied to the development of custom laboratory equipment that is specifically adapted for use with the novel brain tissue clearing technique, CLARITY. A simple, freely available online software tool was used, along with consumer-grade equipment, to produce a brain slicing chamber and a combined antibody staining and imaging chamber. Using standard 3D printers we were able to produce research-grade parts in an iterative manner at a fraction of the cost of commercial equipment. 3D printing provides a reproducible, flexible, simple and cost-effective method for researchers to produce the equipment needed to quickly adopt new methods. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.042
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    ABSTRACT: Bioresorbable filomicelles present many advantageous as drug delivery systems e.g. long circulation time and high loading efficiency. The aim of this study was to develop polylactide/poly(ethylene glycol) (PLA/PEG) filomicelles for drug delivery applications. A series of PLA/PEG diblock copolymers were synthesized using non-toxic initiator, and characterized by means of NMR and GPC. Analysis of morphology of micelles determined by TEM revealed that apart from the weight fraction also the molar mass of PEG and the stereochemistry of PLA block must be considered for tailoring micellar structures. The CMC was found to be dependent on the length and structure of the hydrophobic block. It was observed that the drug loading properties could be improved by selection of appropriate copolymer and encapsulation method. Slower release of paclitaxel was observed for mPEG5000 initiated copolymers than mPEG2000 initiated copolymers. Moreover, the influence of the length of hydrophobic block and its stereoisomeric form on drug release rate was evidenced. Therefore, PLA/PEG filomicelles with good stability, high drug loading capacity and sustained drug release appear most attractive for drug delivery applications. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.032
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    ABSTRACT: Medical devices (MD) for infusion and artificial nutrition are essentially made of plasticized PVC. The plasticizers in the PVC matrix can leach out into the infused solutions and may enter into contact with the patients. In order to assess the risk of patient exposure to these plasticizers we evaluated the migration performance of DEHP, DEHT, DINCH, and TOTM using a model adapted to the clinical use of the MDs. Each PVC tubing sample was immersed in a simulant consisting of a mixture of ethanol/water (50/50 v/v) at 40°C and migration tests were carried out after 24 hours, 72 hours, and 10 days.DEHP had the highest migration ability, which increased over time. The amount of TOTM released was more than 20 times less than that of DEHP, which makes it an interesting alternative. DEHT is also promising, with a migration level three times smaller than DEHP. However, the migration ability of DINCH was similar to DEHP, with the released amounts equaling 1/8th of the initial amount in the tubing after 24 hours of contact. Taking into account the available toxicological data, TOTM and DEHT appear to be of particular interest. However, these data should be supplemented and correlated with clinical and toxicological studies on plasticizers and their metabolites. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.030
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    ABSTRACT: The use of naturally derived excipients to develop enteric coatings offers significant advantages over conventional synthetic polymers. Unlike synthetic polymers, they are biodegradable, relatively abundant, have no daily intake limits or restrictions on use for dietary and nutraceutical products. However, little information is available on their dissolution properties under different gastrointestinal conditions and in comparison to each other. This work investigated the gastric resistance properties of commercially available GRAS-based coating technologies. Three coating systems were evaluated: ethyl cellulose+carboxymethyl cellulose (EC-CMC), ethyl cellulose+sodium alginate (EC-Alg) and shellac+sodium alginate (Sh-Alg) combinations. The minimum coating levels were optimized to meet USP pharmacopoeial criteria for delayed release formulations (<10% release after 2hours in pH 1.2 followed by >80% release after 45min of pH change). Theophylline 150mg tablets were coated with 6.5%, 7%, and 2.75% coating levels of formulations EC-CMC, EC-Alg and Sh-Alg respectively. In vitro dissolution test revealed fast release in pH 6.8 for ethyl cellulose based coatings: t80% value of 65 and 45min for EC-CMC and EC-Alg respectively, while a prolonged drug release from Sh-Alg coating was observed in both pH 6.8 and 7.4 phosphate buffers. However, when more biologically relevant bicarbonate buffer was used, all coatings showed slower drug release. Disintegration test, carried out in both simulated gastric and intestinal fluid, confirmed good mechanical resistance of EC-CMC and EC-Alg coating, and revealed poor durability of Sh-Alg. Under elevated gastric pH conditions (pH 2, 3 and 4), EC-CMC and EC-Alg coatings were broken after 70, 30, 55min and after 30, 15, 15min, respectively, while Sh-Alg coated tablets demonstrated gastric resistance at all pH values. In conclusion, none of the GRAS-grade coatings fully complied with the different biological demands of delayed release coating systems. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.039
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    ABSTRACT: Prothymosin alpha (ProTα) is a conserved mammalian polypeptide with intracellular functions associated with cell proliferation and apoptosis and an extracellular role associated with immunopotentiation. The N-terminal fragment [1-28], which is identical with the immunostimulating peptide thymosin α1 (Tα1), was earlier considered as the immunoactive region of the polypeptide; however, recent data suggest that ProTα may exert a discrete immunomodulating action through its central or C-terminal region, via targeting Toll-like receptor- 4 (TLR4). In this work, a derivative of the C-terminal fragment ProTα[100-109] (ProTα-D1) that can be radiolabeled with (99m)Tc was developed. The biological activity of the non-radioactive (185/187)rhenium-complex of this derivative ([(185/187)Re]ProTα-D1, structurally similar with [(99m)Tc]ProTα-D1) was verified through suitable in vitro bioassays on human neutrophils. Subsequent cell-binding studies revealed specific, time-dependent and saturable binding of [(99m)Tc]ProTα-D1 on neutrophils, which was inhibited by intact ProTα and ProTα[100-109], as well as by a "prototype" TLR4-ligand (lipopolysaccharide from Escherichia coli). Overall, our results support the existence of ProTα-binding sites on human neutrophils, recognizing [(99m)Tc]ProTα-D1, which might involve TLR4. [(99m)Tc]ProTα-D1 may be a useful tool for conducting further in vitro and in vivo studies, aiming to elucidate the extracellular mode of action of ProTα and, eventually, develop ProTα-based immunotherapeutics. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.031
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    ABSTRACT: The aim of this study was to develop a formulation containing fenofibrate and Gelucire(®) 50/13 (Gattefossé, France) in order to improve the oral bioavailability of the drug. Particles from Gas Saturated Solutions (PGSS) process was chosen for investigation as a manufacturing process for producing a solid dispersion. The PGSS process was optimized according to the in vitro drug dissolution profile obtained using a biphasic dissolution test. Using a design of experiments approach, the effects of nine experimental parameters were investigated using a PGSS apparatus provided by Separex(®) (Champigneulles, France). Within the chosen experimental conditions, the screening results showed that the drug loading level, the autoclave temperature and pressure, the connection temperature and the nozzle diameter had a significant influence on the dissolution profile of fenofibrate. During the optimization step, the three most relevant parameters were optimized using a central composite design, while other factors remained fixed. In this way, we were able to identify the optimal production conditions that would deliver the highest level of fenofibrate in the organic phase at the end of the dissolution test. The closeness between the measured and the predicted optimal dissolution profiles in the organic phase demonstrated the validity of the statistical analyses. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.027
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    ABSTRACT: Hydroxypropyl methylcellulose (HPMC), a widely employed film coating polymer, exhibits poor dispersibility in an aqueous medium. Rapid hydration leading to swelling and coherent gel formation is reported to be responsible for this problem. Present study focuses on the use of spray drying based approach for co-processing of HPMC to improve its dispersibility. Dispersion behavior of native HPMC showed formation of large lumps that did not dissolve completely for 40min. However, HPMC co-processed with lactose and sodium chloride exhibited improvement in dispersibility with complete dissolution attained within 20min. Mechanistic insights into improved dispersibility were obtained using contact angle studies, confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM) and scanning TEM (STEM) studies. Co-processed products exhibited higher immersional wetting as determined by sessile drop contact angle technique, which indicated spontaneous incursion of water. CLSM study revealed highly swollen and erodible gel in co-processed products. Novel application of TEM and STEM techniques was developed to understand the nature of mixing achieved during co-processing. Overall the improvement in dispersibility of co-processed products was predominantly due to the alteration in sub-particulate level properties during co-processing. The effect of excipients on the film properties of HPMC, like tensile strength and hygroscopicity, was also assessed. This study provides the comprehensive understanding of role of co-processing on improvement of dispersion behavior of HPMC and helps in the selection of suitable excipients for the same. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.036
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    ABSTRACT: This study provided a convenient approach for large scale production of hydrogenated soya phosphatidylcholine nano-liposome powders using beclometasone dipropionate as model drug and sucrose as proliposome carrier. Fluid-bed coating was employed to manufacture proliposomes by coating sucrose with the phospholipid (5%, 10%, 15% and 20% weight gains), followed by hydration, size reduction using high pressure homogenization, and freeze-drying to yield stable nano-vesicles. High pressure homogenization was compared with probe-sonication in terms of liposome size, zeta potential and drug entrapment. Furthermore, the effect of freeze-drying on vesicle properties generated using both size reduction methods was evaluated. Results have shown that high-pressure homogenization followed by freeze-drying and rehydration tended to yield liposomes smaller than the corresponding vesicles downsized via probe-sonication, and all size measurements were in the range of 72.64-152.50nm, indicating that freeze-drying was appropriate, regardless of the size reduction technique. The Liposomes, regardless of size reduction technique and freeze drying had slightly negative zeta potential values or were almost neutral in surface charge. The entrapment efficiency of BDP in homogenized liposomes was found to increase following freeze-drying, hence the drug entrapment efficiency values in rehydrated liposomes were 64.9%, 57%, 69.5% and 64.5% for 5%, 10%, 15% and 20% weight gains respectively. In this study, we have reported a reliable production method of nano-liposomes based on widely applicable industrial technologies such as fluid-bed coating, high pressure homogenization and freeze-drying. Moreover, sucrose played a dual role as a carrier in the proliposome formulations and as a cryoprotectant during freeze-drying. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.038
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    ABSTRACT: Multifunctional network-structured polymeric coat for woven and knitted forms of crimped polyethylene terephthalate PET graft was developed to limit graft-associated infections. A newly synthesized antibacterial sulfadimethoxine polyhexylene adipate-b-methoxy polyethylene oxide (SD-PHA-b-MPEO) di-block copolymer was employed. Our figures of merit revealed that the formed coat showed a porous topographic architecture which manifested paramount properties, mostly bacterial anti-adhesion efficiency and biocompatibility with host cells. Compared to untreated grafts, the coat presented marked reduction of adhered Gram-positive Staphylococcus epidermidis previously isolated from a patient's vein catheter by 2.6 and 2.3 folds for woven and knitted grafts, respectively. Similarly, bacterial anti-adhesion effect was observed for Staphylococcus aureus by 2.3 and 2.4 folds, and by 2.9 and 2.7 folds for Gram-negative Escherichia coli for woven and knitted grafts, respectively. Additionally, adhesion and growth characteristics of L929 cells on the modified grafts revealed no significant effect on the biocompatibility. In conclusion, coating of PET with (SD-PHA-b-MPEO) is a versatile approach offers the desired bacterial anti-adhesion effect and host biocompatibility. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.041
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    ABSTRACT: Bilosomes represent an evolving vesicular carrier that have been explored for oral vaccines delivery based on its ability to resist enzymes and bile salts in the gastrointestinal tract (GIT). Bilosomes vesicles are formed of bilayer membrane of non-ionic surfactant molecules encompassing bile salts. Although, bilosomes have not been proposed for transdermal drug delivery, this carrier seems to have promising potential in this regard. Accordingly, the aim of this investigation was to assess the capability and safety of utilizing bilosomes for transdermal delivery of tenoxicam (TX) as a model drug. A 3(1)2(2) full factorial design was adopted to study the effects of different formulation parameters on bilosomes properties and select the optimal formulation using Design-Expert(®) software. The selected formulation displayed nano-sized spherical vesicles (242.5±6.43nm) with reasonable entrapment efficiency percent (68.33±2.33%). Confocal laser scanning microscopy confirmed the capability of the flourolabeled bilosomes to penetrate deep within the skin. Both, ex vivo permeation and in vivo skin deposition studies confirmed the superiority of bilosomes over drug solution in delivering TX transdermally. In addition, in vivo histopathological study proved the safety of topically applied bilosomes. In summary, the highlighted results confirmed that bilosomes can be further adopted for delivering drugs transdermally. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.033
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    ABSTRACT: The main purpose of this study was to investigate the feasibility of azithromycin (AZI) - Aerosil 200 solid dispersions specifically with high stability under accelerated condition (40°C/75% RH). Ball milling (BM) and hot-melt extrusion (HME) were used to prepare AZI solid dispersions. The physical properties of solid dispersions were evaluated by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). For solid dispersions prepared with both methods, no crystalline of AZI was detected (except for AZI: Aerosil 200=75: 25) by DSC or PXRD, indicating the amorphous state of AZI in solid dispersions. The FT-IR results demonstrated the loss of crystallization water and the formation of hydrogen bonds between Aerosil 200 and AZI during the preparation of solid dispersions. After 4 weeks storage under accelerated condition, the degree of crystallinity of AZI increased in solid dispersions prepared by BM, whereas for solid dispersions containing AZI, Aerosil 200 and glyceryl behenate (GB) prepared by HME, no crystalline of AZI was identified. This high stability can be attributed to the hydrophobic properties of GB and the presence of hydrogen bonds. Based on the above results, it is inferred the protection of hydrogen bonds between AZI and Aerosil 200 formed during preparation process effectively inhibited the recrystallization of AZI and improved the physical stability of amorphous AZI in the presence of Aerosil 200. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.029
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    ABSTRACT: We describe the development, analytical characterization, stability and preclinical efficacy of AF04, a combination adjuvant comprising the synthetic Toll-Like Receptor 4 (TLR4) agonist, E6020, formulated in AF03, a thermoreversible squalene emulsion. By using AF04 with the recombinant major outer membrane protein of Chlamydia trachomatis (Ct-MOMP) and with the recombinant surface glycoprotein gB from human cytomegalovirus (CMV-gB) as model antigens, we show that AF03 and E6020 can synergize to augment specific antibody and Th-1 cellular immune responses in mice. In terms of formulation, we observe that the method used to incorporate E6020 into AF03 affects its partition between the oil and water phases of the emulsion which in turn has a significant impact on the tolerability (IV pyrogenicity test in rabbits) of this novel adjuvant combination. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.028
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    ABSTRACT: The aim of the present study was to optimize a tablet formulation using a quality by design approach. The selected methodology was based on the variation of the filler grade, taking into account the Particle Size Distribution (PSD) of Active Pharmaceutical Ingredient (API) in order to improve five Critical Quality Attributes (CQAs). Thus, a mixture Design of Experiments (DoE) was performed at pilot scale. The blending step was monitored using Near Infrared (NIR) spectroscopy as process analytical technology tool enabling real-time qualitative process monitoring. Furthermore, some tablets were analyzed by Raman imaging to evaluate the API distribution within the samples. Based on the DoE results, design spaces were computed using a risk-based Bayesian predictive approach to provide for each point of the experimental domain the expected probability to get the five CQAs jointly within the specifications in the future. Finally, the optimal conditions of the identified design space were successfully validated. In conclusion, a design space approach supported by NIR and Raman spectroscopy was able to define a blend that complies with the target product profile with a quantified guarantee or risk. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.025
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    ABSTRACT: Novel polymer-modified thermosensitive liposomes were developed for the delivery of indomethacin in order to control its release profile. When attached to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes, the end functionalized C12H25-poly(N-isopropylacrylamide)-COOH (C12H25-PNIPAM-COOH) polymer was membrane-disruptive in a temperature-dependent manner. The interest for this polymer is driven by its famous lower critical solution temperature (LCST) behavior, where heating an aqueous solution of PNIPAM above 32°C induces nanophase separation and polymer chain aggregation. The physicochemical/structural behavior of these polymer-modified thermosensitive liposomes was found to depend on the PNIPAM:lipid molar ratio and the composition of the polymeric guest. The incorporation of PNIPAM has caused alterations in the thermotropic behavior of DPPC liposomes, as the differential scanning calorimetry (DSC) experiments revealed. The drug loading and the release were found to be strongly dependent on the thermotropic characteristics of the PNIPAM grafted DPPC liposomes. Namely, the in vitro release is immediate at 37°C (>LCST) ("burst" effect), while the prepared mixed nanocarriers did not release the encapsulated bioactive substance at <32°C (<LCST). Thus the thermosensitivity and the drug loading/release properties of the prepared formulations can be modulated by varying the ratio of DPPC/PNIPAM components, as well as the molecular characteristics of the polymeric guest. Copyright © 2015 Elsevier B.V. All rights reserved.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.014
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    ABSTRACT: In this work, we investigate the compaction activity of a sequential alpha,epsilon-peptide composed of l-lysines towards two RNA targets, in view of its possible pharmaceutical application in RNA-targeting and RNA delivery. The basic oligolysine, object of the present study, proved not only to be efficient in compacting the single-stranded polyA RNA, but also to strongly interact with the polyA·polyU complex, as evidenced by CD-binding and UV-melting experiments. In particular, the marked differences in the CD spectra of the RNA targets upon addition of the peptide, as well as the different UV melting behaviour for the polyA·polyU complex in the presence and absence of the peptide, sustain the hypothesis of a strong RNA compaction capacity of the alpha,epsilon-oligolysine. Finally, by using HPLC analysis, we found a good resistance of the peptide against the lytic action of human serum, an important requirement in view of in vitro/in vivo biological assays. Copyright © 2015. Published by Elsevier B.V.
    International Journal of Pharmaceutics 03/2015; DOI:10.1016/j.ijpharm.2015.03.011