Aims
Chronic osteomyelitis, including implant-related prosthetic joint infection, is extremely difficult to cure. We develop vancomycin containing release systems from poly(
d
,
l
-lactide) (PDLLA) ...and poly(
d
,
l
-lactide-co-glycolide) (PLGA) composites with beta-tricalcium phosphate (β-TCP) to treat methicillin-resistant
Staphylococcus aureus
osteomyelitis. We ask whether vancomycin containing PDLLA/β-TCP and PLGA/β-TCP composites will prevent early biofilm formation, allow cell proliferation and osteogenic differentiation, and stimulate osteogenic signaling molecules in the absence of an osteogenic medium.
Methods
Composites were produced and characterized with scanning electron microscopy.
In vitro
vancomycin release was assessed for 6 weeks. Biofilm prevention was calculated by crystal violet staining. Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) and osteosarcoma cell (SaOS-2) proliferation and differentiation were assessed with water soluble tetrazolium salt and alkaline phosphatase (ALP) staining. Real-time quantitative polymerase chain reaction defined osteogenic signaling molecules for hBM-MSCs.
Results
Totally, 3.1 ± 0.2 mg and 3.4 ± 0.4 mg vancomycin released from PDLLA/β-TCP and the PLGA/β-TCP composites, respectively, and inhibited early biofilm formation. hBM-MSCs and SaOS-2 cells proliferated on the composites and stimulated ALP activity of cells. Runt-related transcription factor 2 (RUNX2) and SRY-Box transcription Factor 9 (SOX9) expressions were, however, lower with composites when compared with control.
Conclusion
Vancomycin containing PDLLA/β-TCP and PLGA/β-TCP composites inhibited early biofilm formation and proliferated and differentiated hBM-MSCs and SaOS-2 cells, but osteogenesis-related RUNX2 and SOX9 transcription factors were not strongly expressed in the absence of an osteogenic medium for 14 days.
Alzheimer’s Disease (AD) is one of the most challenging diseases faced by humankind. AD is still not classified as curable because of the complex structure of pathologies underlying it. As the mean ...life expectancy of the world population constantly increases, the prevalence of AD and treatment costs for AD also grow rapidly. Current state of the art for AD treatment mainly consists of palliative therapy aimed at providing symptomatic relief and improving the standard of living in patients with AD. However, different research groups are working on more effective and safe drug delivery options aimed at both symptomatic relief and treatment of the underlying mechanisms. In this review, the current prevalence of AD, health costs, pathologies, and available treatment options including the ones in the market and/or under trial have been reviewed. Data in the existing literature have been presented, and future opportunities have been discussed. It is our belief that these nanotechnological products provide the required efficacy and safety profiles to enable these formulations go through phase studies and enter the market after regulatory authority approval, as with cancer. Last, but not the least the metabolomic studies will be providing useful informative data on the early diagnosis of AD, thus may be clinical implications might be delayed with the administration of therapeutic agents at the initial state of the disease.
Developing a new drug molecule is not only time-consuming and expensive, but also mostly a failing process. However, improving bioavailability, targetability, efficacy or safety of old drugs could be ...more effective way to use them in clinic. For these purposes, so many strategies including individualising drug therapy, nanoparticle-based drug delivery systems, drug conjugates, therapeutic drug monitoring, stimuli-sensitive targeted therapy are investigated intensely. Depending on the desired application or targeted site, nanoparticles can be administrated as orally, locally, topically and systemically. Currently, the Food and Drug Administration and the European Medicines Agency approved nanoparticles are mostly aimed to treat cancer. Although some of these formulations were approved by Food and Drug Administration and/or European Medicines Agency to use in clinic, most of them have fell down to pass either pre-clinical or clinical trials. To have high approval rate, failure reasons need to be better understand.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Nanofibers became one of the major research areas for drug delivery and tissue engineering applications in the last decade. Depending on the simplicity of the preparation method and high drug loading ...capacity, nanofibers provide many advantages for therapeutic perspectives. In addition, combined systems such as embedding nanoparticles into the nanofiber structures provide a second option for delivery of dual active ingredients in the same formulation. The release rate of the active ingredients can also be modified easily by the formulation parameters depending on the desired release time for treatment. Nanofibers systems are used for the delivery of antibiotics, anticancer drugs, analgesics, hemostatic agents and various proteins for tissue engineering purposes. In addition, various applications such as medical device coating also provide new insights for the clinical use of nanofibers. The most commonly used technique for preparation of nanofibers is the electrospinning, which provides feasibility background for scale up process from laboratory to the industrial applications. The main boundary for nanofibers is the limitations for systemic route. Nanofibers are mainly designed for the delivery of active ingredients for local purposes. Regardless of the therapeutic aim, nanofibers are also perfect 3 dimensional structures that are suitable for tissue regeneration. They provide matrix structure for cell regeneration especially in applications for wound healing. This review is mainly focused on the recent advances on the preparation of nanofibers, applications for drug delivery, tissue engineering and wound healing purposes.
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•There are no published reports for electrochemical determination of Molnupiravir in any matrix.•The first electrochemical validated, sensitive, cheap, easy and fast method for ...determination of Molnupiravir in pharmaceutical preparations.•Reduced GO has excellent conductivity, thermal and chemical stability for sensor application.
A direct, simple, and sensitive method based on electrochemical deposition of reduced graphene oxide (rGO) on a glassy carbon electrode (GCE) using cyclic voltammetry (CV) was developed for Molnupiravir (MOL) quantitative analysis. Here, the electrochemical oxidation of MOL was examined using square wave voltammetry (SWV) and a well-defined peak at 0.2 V was measured against the Ag/AgCl reference electrode with the rGO sensor in Britton-Robinson pH 9 buffer. Various operational parameters for MOL analysis such as pH of supporting electrolyte, instrumental parameters, electropolymerization cycles, and GO concentration were optimized. The sensor exhibited a linear range from 0.09 to 4.57 μM with a detection limit of 0.03 µM. The electrochemical response of the rGO sensor was characterized by electrochemical impedance spectroscopy and CV. The character of current and reversibility of the electrode reaction, the number of electrons and protons transferred were studied by the CV method. The developed sensor was validated according to the International Council for Harmonisation (ICH) guidelines. Validation parameters, such as stability, linearity, sensitivity, accuracy, precision, recovery, robustness and ruggedness were evaluated according to the ICH requirements. The developed sensor was successfully applied for the quantification of MOL in capsule formulations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Atorvastatin is commonly used as a cholesterol lowering agent in patients. Recently, the neuroprotective effects of atorvastatin became the focus of many research studies. In this study, we have ...formulated chitosan microspheres containing atorvastatin calcium. In-vitro characterization of chitosan microspheres and quantification of atorvastatin calcium from formulations were also evaluated. The neuroprotective efficiency of atorvastatin calcium was investigated by an experimental spinal cord injury model. Atorvastatin calcium microspheres were implanted at the laminectomy area (1 mg/kg) immediately after trauma. Twenty-four hours after injury, motor functions of animals were scored according to modified Tarlov Scale. In spinal cord tissues tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and lipid peroxidation levels were quantified and ultrastructural changes have been investigated. The results of all parameters indicate that microspheres containing atorvastatin calcium were capable of improving functional outcome, attenuating the expression of TNF-α, IL-1β and IL-6; lowering lipid peroxidation levels and maintaining the preservation of the cellular uniformity.
Antiviral drugs have gained much more attention in recent years due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and many drug candidates are currently under ...investigation in order to end pandemic. Molnupiravir, a prodrug of the synthetic nucleoside derivative N4-hydroxycytidine, is one of the promising candidates for SARS-CoV-2 treatment. In this study, a RP-HPLC method was developed for the determination of Molnupiravir and applied for in vitro permeability studies of self-emulsifying drug delivery system (SEDDS) formulations using Caco-2 cell line. Discovery® HS C18 Column (75 ×4.6 mm, 3 µm) was used at 30 °C. Isocratic elution was performed with ACN:water (20:80 v/v) mixture. The flow rate was 0.5 mL/min and UV detection was at 240 nm. Molnupiravir eluted within 5 min. Molnupiravir was exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions. Peak homogeneity data of Molnupiravir in the stressed samples peak obtained using photodiode array detector, in the stressed sample chromatograms, demonstrated the specificity of the method for their estimation in presence of degradants. The developed method was validated according to the International Council for Harmonisation (ICH) guidelines and found to be linear within the range 0.1–60.0 μg/mL. The method was simple, rapid, selective, sensitive, accurate, precise, robust and rugged. Thus, it was applied successfully for permeability quantitation of Molnupiravir in nanoformulations. The apparent permeability of Molnupiravir in SEDDS formulations, which have droplet size under 350 nm, was calculated as 3.20 ± 0.44 × 10−6 cm/s.
•A reliable and stability indicating RP-HPLC method was validated for quantification of molnupiravir.•This is the first HPLC method developed for the molnupiravir analysis.•Validation studies were performed according to ICH requirements.•The developed method shows simplicity, selectivity and sensitivity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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Swallowing oral solid dosage forms is challenging in patients with dysphagia who are at risk of aspiration or choking. The most common method to facilitate drug administration in ...dysphagia patients is to mix the powdered drug with a small amount of thickened water, however little is known about the effects of this method on in vivo bioavailability of drugs. This study aimed to evaluate the impact of thickened liquids on dissolution rate and bioavailability of levetiracetam as a model drug. Powdered commercial tablets of levetiracetam, carbamazepine, atenolol and cefixime were mixed with water thickened with two commercial thickeners, modified maize starch (MS) and xanthan gam (XG), at three thickness levels: nectar, honey and pudding in test groups, and mixed with only water in the control group. At the first stage, the effects of thickened water on in vitro drug release of 4 drugs (levetiracetam, carbamazepine, atenolol and cefixime) were tested by using dialysis membrane method. Addition of both thickeners significantly reduced the release of three drugs compared to the control group, except carbamazepine. Levetiracetam which had the highest solubility was chosen as the model drug for in vivo experiments. In the second stage, New Zealand albino female rabbits (n=24) were divided into two groups as: control group (water+drug, n=6) and test group (thickened water+drug, n=18). Powdered levetiracetam tablets were mixed with water thickened with XG (n=9, 1.2%, 2.4%, 3.6%) and MS (n=9, 4%, 6%, 8%) at three thickness levels and administered to the rabbits by intragastric gavage. Blood samples were collected at 9 time points following administration. After two-weeks of wash-out, test groups were crossed over and sample collection was repeated. Blood samples were analysed using liquid chromatography with tandem mass spectrometry (LC-MS/MS). An in vitro-in vivo correlation (IVIVC) model was developed using in vitro drug dissolution (%) and in vivo plasma concentrations of levetiracetam for control group and test groups. The peak plasma concentration (Cmax) was lower and time to reach Cmax (tmax) was relatively higher in test groups compared to control group. The lowest Cmax was detected at the highest thickness level, however, the differences between groups were not statistically significant (p=0.117 and p=0.495 for Cmax and tmax, respectively). No significant difference in total amount of levetiracetam absorbed (AUC) was found between groups (p=0.215 and p=0.183 for AUCinfinity and AUClast, respectively). The comparisons according to the type of thickener also revealed that pharmacokinetic parameters did not significantly differ between groups, except for a significantly lower Cmax when drug was mixed with MS-thickened water at nectar consistency (1.2%) compared to drug mixed with XG (4%) at the same thickness level (p=0.038). A good correlation was observed between in vitro and in vivo data, which was characterized by higher r2 values as the concentration of the thickening agents was increased, but not for all thickness levels studied, indicating an inability of this in vitro model to fully predict the in vivo response. These results suggest that regardless of the thickness level, the administration of levetiracetam with two commercial thickening agents commonly used in dysphagia for safe swallowing, do not affect the pharmacokinetic efficiency and thus, the bioavailability of the drug.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Synthetic micro/nanomotors (MNMs) are novel, self-propelled nano or microscale devices that are widely used in drug transport, cell stimulation and isolation, bio-imaging, diagnostic and monitoring, ...sensing, photocatalysis and environmental remediation. Various preparation methods and propulsion mechanisms make MNMs "tailormade" nanosystems for the intended purpose or use. As the one of the newest members of nano carriers, MNMs open a new perspective especially for rapid drug transport and gene delivery. Although there exists limited number of in-vivo studies for drug delivery purposes, existence of in-vitro supportive data strongly encourages researchers to move on in this field and benefit from the manoeuvre capability of these novel systems. In this article, we reviewed the preparation and propulsion mechanisms of nanomotors in various fields with special attention to drug delivery systems.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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