(1) Background: Many drugs possess poor bioavailability, and many strategies are available to overcome this issue. In this study, smartFilm technology, i.e., a porous cellulose matrix (paper), in which the active compound can be loaded onto in an amorphous state was utilised for oral administration to improve the solubility and bioactivity of a poorly soluble BSC class IV antibiotic. (2) Methods: Norfloxacin was used as the model drug and loaded into commercially available paper. The resulting norfloxacin-loaded smartFilms were transformed into smartFilm granules via wet granulation and the resulting norfloxacin-loaded smartFilm granules were transformed into norfloxacin-loaded tablets made from paper, i.e., smartFilm tablets. The crystalline state of norfloxacin was investigated, as well as the pharmaceutical properties of the granules and the tablets. The bioactivity of the smartFilm tablets was assessed in vitro and ex vivo to determine the antibacterial activity of norfloxacin. The results were compared to a physical mixture tablet that contained non-loaded paper granules and equal amounts of norfloxacin as a crystalline powder. (3) Results: Norfloxacin-loaded smartFilm granules and norfloxacin-loaded smartFilm tablets contained norfloxacin in an amorphous state, which resulted in an improved and faster release of norfloxacin when compared to the physical mixture tablet. The bioactivity was up to three times higher when compared to the physical mixture tablet. The ex vivo model was demonstrated to be a useful tool that allows for a fast and cost-effective discrimination between “good” and “bad” formulations. It provides realistic physiological conditions and can therefore yield meaningful, additional biopharmaceutical information that cannot be assessed in classical in vitro experiments. (4) Conclusions: smartFilm tablets are a promising, universal, industrially feasible and cost-effective formulation strategy for improved solubility and enhanced bioactivity of poorly soluble drugs.
Granulated and non-granulated smartFilm tablets loaded with norfloxacin (NOR) were investigated using terahertz (THz) time-domain spectroscopy (TDS) and x-ray powder diffraction (XRD). THz TDS was more sensitive to crystalline NOR, as through THz TDS, partial crystallization of NOR after wet granulation can be observed, which was not detectable by XRD. The results obtained by THz TDS were used for quantitative crystallinity assessment in the smartFilm tablets.
(1) Background: Amorphous drug systems are an intensively studied approach to overcome the insufficient bioavailability of poorly soluble drugs. Here, paper tablets were studied, which were made from cellulose-based paper matrices loaded with norfloxacin. Moreover, wet granulation was introduced as an additional processing step for improving the flowability of the solids, which is necessary when considering production on an industrial scale. (2) Methods: The possible impact of the wet granulation on the crystallinity of norfloxacin was studied by examining granulated and non-granulated samples. Crystallinity investigations were performed using X-ray powder diffraction (XRD) and terahertz time-domain spectroscopy (THz TDS). (3) Results: THz TDS allowed for a more straightforward crystallinity assessment than XRD. Moreover, using THz TDS, it was possible to detect minor changes in the crystallinity of the API after the granulation, whereas this was not possible with the XRD analysis. (4) Conclusions: THz TDS results indicate a partial crystallization of norfloxacin due to the wet granulation. Depending on the formulation, THz TDS can serve as a beneficial and advantageous tool to determine the crystallinity of an API.
Multidrug resistance in pathogenic bacteria has become a significant public health concern. As an alternative therapeutic option, antimicrobial photodynamic therapy (aPDT) can successfully eradicate antibiotic-resistant bacteria with a lower probability of developing resistance or systemic toxicity commonly associated with the standard antibiotic treatment. Parietin (PTN), also termed physcion, a natural anthraquinone, is a promising photosensitizer somewhat underrepresented in aPDT because of its poor water solubility and potential to aggregate in the biological environment. This study investigated whether the complexation of PTN with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) could increase its solubility, enhance its photophysical properties, and improve its phototoxicity against bacteria. At first, the solubilization behavior and complexation constant of the PTN/HP-β-CD inclusion complexes were evaluated by the phase solubility method. Then, the formation and physicochemical properties of PTN/HP-β-CD complexes were analyzed and confirmed in various ways. At the same time, the photodynamic activity was assessed by the uric acid method. The blue light-mediated photodegradation of PTN in its free and complexed forms were compared. Complexation of PTN increased the aqueous solubility 28-fold and the photostability compared to free PTN. PTN/HP-β-CD complexes reduce the bacterial viability of Staphylococcus saprophyticus and Escherichia coli by > 4.8 log and > 1.0 log after irradiation, respectively. Overall, the low solubility, aggregation potential, and photoinstability of PTN were overcome by its complexation in HP-β-CD, potentially opening up new opportunities for treating infections caused by multidrug-resistant bacteria.
(1) Background: Numerous oral drugs exhibit limited bioavailability due to their poor solubility and poor intestinal permeability. The smartFilm technology is an innovative approach that improves the drug aqueous solubility via incorporating the drug in an amorphous state into a cellulose-based matrix, i.e., paper. smartFilms can be transformed into a free-flowing physical form (i.e., paper granules) that can be compressed into tablets with optimum physico-chemical and pharmaceutical properties. The aim of this study was to investigate if smartFilm tablets are suitable for improved oral delivery of poorly water-soluble drugs. (2) Methods: Curcumin is a poorly soluble drug with low intestinal permeability and was used for the production of curcumin-loaded smartFilms. The curcumin-loaded smartFilms were transferred into smartFilm granules which were then compressed into curcumin-loaded smartFilm tablets. The tablets were characterized regarding their physico-chemical and pharmaceutical properties, and the intestinal permeability of curcumin was determined with the ex vivo porcine intestinal model. The ex vivo intestinal permeability of curcumin from the smartFilm tablets was compared to a physical mixture of curcumin and paper and to a classical and to an innovative commercial product, respectively. (3) Results: The produced curcumin-loaded smartFilm tablets fulfilled the European Pharmacopoeia requirements, incorporated curcumin in amorphous state within the cellulose matrix and exhibited an enhanced dissolution rate. The ex vivo intestinal permeation data were shown to correlate to the in vitro dissolution data. The ex vivo intestinal permeation of curcumin from the smartFilm tablets was about two-fold higher when compared to the physical mixture and the classical commercial product. No differences in the ex vivo bioavailability were found between the smartFilm tablets and the innovative commercial product. (4) Conclusions: smartFilm tablets are a cost-effective and industrially feasible formulation approach for the formulation of poorly water-soluble drugs, i.e., BCS class II and IV drugs.
(1) Background: The ex vivo porcine ear model is often used for the determination of the dermal penetration efficacy of chemical compounds. This study investigated the influence of the post-slaughter storage time of porcine ears on the dermal penetration efficacy of chemical compounds. (2) Methods: Six different formulations (curcumin and different fluorescent dyes in different vehicles and/or nanocarriers) were tested on ears that were (i) freshly obtained, (ii) stored for 24 or 48 h at 4 °C after slaughter before use and (iii) freshly frozen and defrosted 12 h before use. (3) Results: Results showed that porcine ears undergo post-mortem changes. The changes can be linked to rigor mortis and all other well-described phenomena that occur with carcasses after slaughter. The post-mortem changes modify the skin properties of the ears and affect the penetration efficacy. The onset of rigor mortis causes a decrease in the water-holding capacity of the ears, which leads to reduced penetration of chemical compounds. The water-holding capacity increases once the rigor is released and results in an increased penetration efficacy for chemical compounds. Despite different absolute penetration values, no differences in the ranking of penetration efficacies between the different formulations were observed between the differently aged ears. (4) Conclusions: All different types of ears can be regarded to be suitable for dermal penetration testing of chemical compounds. The transepidermal water loss (TEWL) and/or skin hydration of the ears were not correlated with the ex vivo penetration efficacy because both an impaired skin barrier and rigor mortis cause elevated skin hydration and TEWL values but an opposite penetration efficacy. Other additional values (for example, pH and/or autofluorescence of the skin) should, therefore, be used to select suitable and non-suitable skin areas for ex vivo penetration testing. Finally, data from this study confirmed that smartFilms and nanostructured lipid carriers (NLC) represent superior formulation strategies for efficient dermal and transdermal delivery of curcumin.
Many orally administrated drugs exhibit poor bioavailability due to their limited solubility. The smartFilm technology is an innovative approach to improve the drug aqueous solubility, where the drug is embedded within the matrix of cellulose-based paper in an amorphous state, hence increasing its solubility. Despite its proven effectiveness, smartFilms, i.e., pieces of paper, exhibit limited flowability and are not easy to swallow, and thus oral administration is not convenient. In addition, there is a lack of knowledge of their mechanical behavior under compression. This study aimed to transform unloaded smartFilms, i.e., paper, into a flowable physical form and investigated its mechanical behavior when compressed. Granules made of paper were prepared via wet granulation and were compressed into tablets. The influence of using different amounts and forms of sucrose, as a binder, on the pharmaceutical properties of the produced granules and tablets was studied and the most suitable composition was identified by using instrumented die experiments. For this, the Poisson’s ratio and Young’s modulus were determined for different compaction force levels and the deformation behavior was estimated with the Heckel mathematical model. All granule batches showed good flowability with angle of repose values between 25–35°. Granule batches with ≤30% dry sucrose content produced tablets that fulfilled the European Pharmacopeia requirements, and the compaction behavior of the granules was found to be comparable to the behavior of classical binders and compression enhancers. Paper can be transferred into granules. These granules can be used as suitable intermediate products for the production of tablets made of paper in large, industrial scale.
Letrozole (LTZ), an aromatase inhibitor with poor aqueous solubility, is used as the first line treatment for hormonal sensitive breast cancer in postmenopausal women. The purpose of the current study is to develop hyaluronic acid (HA)/chitosan (Cs)-coated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles for the delivery of LTZ to improve therapeutic efficacy, control release and minimize side effects of LTZ. PLGA nanoparticles were prepared, and the effect of various parameters on particle size, surface charge, and encapsulation efficiency was extensively studied. The morphology of nanoparticles was visualized using transmission electron microscopy (TEM), and drug-polymer interactions were studied using differential scanning calorimetry (DSC) and Fourier transform-infrared spectroscopy (FT-IR). The in vitro release kinetics and effect of freeze-drying process on the physicochemical characteristics of nanoparticles were also evaluated. Moreover, the in vivo acute toxicities of blank and drug-loaded nanoparticles were assessed. PLGA nanoparticles exhibited nanosized (464.3 ± 2.1 nm) spherical particles, negative surface charge (zeta-potential of − 10.5 ± 0.4 mV), and high drug encapsulation efficiency of 63.9 ± 3.7% and sustained drug release pattern over 48 h. The in vivo acute toxicity study revealed that the nanoparticles were well tolerated at a dose of 300 mg/kg. HA/Cs-coated PLGA nanoparticles might provide a promising system for LTZ delivery and further investigations could confirm their potential efficacy in breast cancer therapy.
Skin damage exposes the underlying layers to bacterial invasion, leading to skin and soft tissue infections. Several pathogens have developed resistance against conventional topical antimicrobial treatments and rendered them less effective. Recently, several nanomedical strategies have emerged as a potential approach to improve therapeutic outcomes of treating bacterial skin infections. In the current study, nanofibers were utilized for topical delivery of the antimicrobial drug vancomycin and evaluated as a promising tool for treatment of topical skin infections. Vancomycin-loaded nanofibers were prepared via electrospinning technique, and vancomycin-loaded nanofibers of the optimal composition exhibited nanosized uniform smooth fibers (ca. 200 nm diameter), high drug entrapment efficiency and sustained drug release patterns over 48 h. In vitro cytotoxicity assays, using several cell lines, revealed the biocompatibility of the drug-loaded nanofibers. In vitro antibacterial studies showed sustained antibacterial activity of the vancomycin-loaded nanofibers against methicillin-resistant Staphylococcus aureus (MRSA), in comparison to the free drug. The nanofibers were then tested in animal model of superficial MRSA skin infection and demonstrated a superior antibacterial efficiency, as compared to animals treated with the free vancomycin solution. Hence, nanofibers might provide an efficient nanodevice to overcome MRSA-induced skin infections and a promising topical delivery vehicle for antimicrobial drugs.
BACKGROUND Intravenous administration of parenteral nutrition (PN) admixtures containing 4-oil lipid injectable emulsion (ILE) in preterm neonates is usually prohibited because of limited clinical data. The authors evaluated the stability, safety, and efficacy of PN admixtures containing 4-oil ILE, for the first time, in preterm neonates. METHODS A series of PN admixtures were prepared for consecutive administration in preterm neonates over a period of 15 days. Admixture stability was assessed after 24 hours of storage at 25 and 37 °C via visual inspection and measurement of mean droplet size (MDS). Safety and efficacy of the admixtures in preterm neonates were assessed via serum triglyceride levels and body weight increase measurements, respectively. RESULTS PN admixtures were stable at 25 °C and had MDS ˂500 nm. After 15 days, there was a significant increase in body weight (P ≤ .0001) and level of serum triglycerides (P ≤ .0001), compared with the level before PN administration. CONCLUSIONS PN admixtures containing 4-oil ILE were stable at 25 °C and showed instability at 37 °C. Therefore, it is recommended to keep the temperature during administration of PN admixtures at 25 °C. PN admixtures were well tolerated and safe over a period of 8 days while providing a balanced fatty acid supply. Tight monitoring of serum triglyceride level is essential, particularly in neonates of low birth weight and/or young gestational age, to avoid hypertriglyceridemia. Hence, the use of these PN admixtures is expected to be beneficial in terms of being cost-effective and reducing the contamination risks.
OBJECTIVES:Drug incompatibilities may compromise the safety and effectiveness of combined drugs and result in mild-to-serious clinical complications, such as catheter obstruction, loss of drug efficacy, formation of toxic derivatives and embolism. Various preventive strategies have been implemented to overcome drug incompatibilities with limited success. This review presents an innovative approach to prevent drug incompatibilities via isolating the incompatible drugs into nanostructures.KEY FINDINGS:Several examples of incompatible drugs may be loaded separately into nanostructures of various types. Physicochemical characteristics and biocompatibility of the nanomaterials that are being utilized to prevent physicochemical incompatibilities should be carefully considered.CONCLUSIONS:There is a new era of exploiting nanomaterials in overcoming various types of physicochemical incompatibilities, with additional benefits of further improvements in pharmacokinetic profiles and pharmacological actions of the administered drugs.
Antimicrobial resistance is one of the most significant health challenges worldwide. Meropenem is a broad spectrum beta-lactam antibiotic that possesses high activity against Gram-positive and Gram-negative bacteria. However, it has a short plasma half-life, and thus requiring frequent administration of high doses. For the first time, meropenem-loaded chitosan nanoparticles were prepared and evaluated as a potential tool to overcome antimicrobial resistance and to improve pharmacokinetics of the drug. Spherical nanosized particles were prepared and demonstrated ultrahigh encapsulation efficiency of meropenem (i.e. 76.3%). The nanoparticles could be stored in a freeze-dried powdered form while maintaining their physicochemical characteristics. In vitro, higher antibacterial activities of the drug-loaded nanoparticles were observed against methicillin-sensitive and methicillin-resistant Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae, as compared to the free drug. The nanoparticles were then tested in a septic rat model of Klebsiella pneumoniae and showed exceptional improvement of survival and bacterial clearance, as compared to the animals treated with the free drug. Hence, meropenem-loaded chitosan nanoparticles might have great potential for overcoming antimicrobial resistance.