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Fused Deposition Modelling (FDM) 3D printers have gained significant popularity in the pharmaceutical and biomedical industries. In this study, a new biomaterial filament was developed by preparing a polylactic acid (PLA)/calcium peroxide (CPO) composite using wet solution mixing and extrusion. The content of CPO varied from 3% to 24% wt., and hot-melt extruder parameters were optimised to fabricate 3D printable composite filaments. The filaments were characterised using an X-ray diffraction analysis, surface morphology assessment, evaluation of filament extrudability, microstructural analysis, and examination of their rheological and mechanical properties. Our findings indicate that increasing the CPO content resulted in increased viscosity at 200 °C, while the PLA/CPO samples showed microstructural changes from crystalline to amorphous. The mechanical strength and ductility of the composite filaments decreased except for in the 6% CPO filament. Due to its acceptable surface morphology and strength, the PLA/CPO filament with 6% CPO was selected for printability testing. The 3D-printed sample of a bone scaffold exhibited good printing quality, demonstrating the potential of the PLA/CPO filament as an improved biocompatible filament for FDM 3D printing.
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The latest advancements in bone scaffold technology have introduced novel biomaterials that have the ability to generate oxygen when implanted, improving cell viability and tissue maturation. In this paper, we present a new oxygen-generating polylactic acid (PLA)/calcium peroxide (CPO) composite filament that can be used in 3D printing scaffolds. The composite material was prepared using a wet solution mixing method, followed by drying and hot melting extrusion. The concentration of calcium peroxide in the composite varied from 0% to 9%. The prepared filaments were characterized in terms of the presence of calcium peroxide, the generated oxygen release, porosity, and antibacterial activities. Data obtained from scanning electron microscopy and X-ray diffraction showed that the calcium peroxide remained stable in the composite. The maximum calcium and oxygen release was observed in filaments with a 6% calcium peroxide content. In addition, bacterial inhibition was achieved in samples with a calcium peroxide content of 6% or higher. These results indicate that an optimized PLA filament with a 6% calcium peroxide content holds great promise for improving bone generation through bone cell oxygenation and resistance to bacterial infections.
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The study aimed to develop two types of dry powder inhaler (DPI) formulations containing glucagon-like peptide-1(7-36) amide (GLP-1): carrier-free (drug alone, no excipients) and carrier-based DPI formulations for pulmonary delivery of GLP-1. This is the first study focusing on the development of excipient free GLP-1 DPI formulations for inhaled therapy in Type 2 diabetes. The aerosolisation performance of both DPI formulations was studied using a next generation impactor and a DPI device (Handihaler®) at flow rate of 30 L min-1. Carriers employed were either a 10% w/w glycine-mannitol prepared by spray freeze drying or commercial mannitol. Spray freeze dried (SFD) carrier was spherical and porous whereas commercial mannitol carrier exhibited elongated particles (non-porous). GLP-1 powder without excipients for inhalation was prepared using spray drying and characterised for morphology including size, thermal behaviour, and moisture content. Spray dried (SD) GLP-1 powders showed indented/dimpled particles in the particle size range of 1-5 µm (also mass median aerodynamic diameter, MMAD: <5 µm) suitable for pulmonary delivery. Across formulations investigated, carrier-free DPI formulation showed the highest fine particle fraction (FPF: 90.73% ± 1.76%, mean ± standard deviation) and the smallest MMAD (1.96 µm ± 0.07 µm), however, low GLP-1 delivered dose (32.88% ± 7.00%, total GLP-1 deposition on throat and all impactor stages). GLP-1 delivered dose was improved by the addition of SFD 10% glycine-mannitol carrier to the DPI formulation (32.88% ± 7.00%-45.92% ± 5.84%). The results suggest that engineered carrier-based DPI formulations could be a feasible approach to enhance the delivery efficiency of GLP-1. The feasibility of systemic pulmonary delivery of SD GLP-1 for Type 2 diabetes therapy can be further investigated in animal models.
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Diabetes Mellitus Tipo 2 , Inhaladores de Polvo Seco , Administración por Inhalación , Aerosoles , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Portadores de Fármacos , Excipientes , Péptido 1 Similar al Glucagón , Humanos , Tamaño de la Partícula , PolvosRESUMEN
BACKGROUND: Various studies have explored potential therapeutic applications of capsaicin in human medicine, for example in pain, obesity, cancer, cardiovascular and respiratory disease. The aim of this scoping review was to identify and chart available evidence on therapeutic applications of capsaicin in humans using any mode of capsaicin delivery to treat conditions of the respiratory system. METHODS: Electronic bibliographic databases (Web of Science, PubMed, Medline, ScienceDirect, Embase, Scopus) were searched from inception to 2021 to identify experimental studies reporting clinical outcomes of therapeutic applications of capsaicin. Studies with or without control group published in peer-reviewed journals were included. Animal studies, studies of human cell lines, and physiological proof of concept studies were excluded. Reviewer pairs independently double-screened 2799 search results for inclusion. RESULTS: Twenty-three original studies were included. Capsaicin has been investigated for the treatment of non-allergic rhinitis (n = 15), nasal polyposis (n = 3), allergic rhinitis (n = 2), unexplained chronic cough (n = 2), and prevention of aspiration pneumonia (n = 1). Modes of delivery included intranasal application (nasal spray, soaked pads, solution), inhalation, ingestion, and aural ointment. Seventeen studies reported positive effects of capsaicin on clinical outcomes for rhinitis, nasal polyposis, chronic cough, and pneumonia. Sixteen studies reported on the safety of capsaicin, with no reports of significant adverse events and overall fair to good patient acceptability. CONCLUSION: While the evidence identified in this review has limited implications for clinical practice, studies support the general safety of capsaicin as administered in these studies and highlight emerging strands of research and clinical hypotheses which warrant further examination.
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Pólipos Nasales , Rinitis Alérgica , Rinitis , Animales , Capsaicina , Humanos , Pólipos Nasales/inducido químicamente , Sistema Respiratorio , Rinitis/inducido químicamente , Rinitis Alérgica/tratamiento farmacológicoRESUMEN
In the cosmeceutical field, it is essential to develop topical delivery systems which would allow drugs to create a depot and permeate within the skin. The aim of the present study was to develop composite nanofibers of polyvinyl alcohol/quercetin/essential oils using the electrospinning technique, and assess their efficiency in acne alleviation. Quercetin was chosen due to its anti-inflammatory, anti-oxidant, and antibacterial activities. Nanofibers were characterized for their morphology, ex-vivo deposition/permeation, physical/mechanical integrity, thermal properties, and chemical characteristics. In addition, the anti-bacterial efficacy was tested on Propionibacterium acne (P. acne), and a cytotoxicity assay was carried out. Lastly, an experimental clinical trial was conducted on acne patients, where the percentage reduction of inflammatory, non-inflammatory and total acne lesions was taken as evaluation criterion. Results showed that quercetin was successfully loaded into the nanofibers which were homogenously dispersed. They showed a reasonable skin deposition percentage of 28.24% ± 0.012, a significantly higher antibacterial efficacy against Propionibacterium acne than quercetin alone, and were utterly safe on skin fibroblastic cells. Upon clinical examination on acne patients, the nanofibers showed 61.2%, 14.7%, and 52.9% reduction of inflammatory, comedonal, and total acne lesions respectively, suggesting a promising topical anti-acne delivery system.
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Acné Vulgar , Nanofibras , Acné Vulgar/tratamiento farmacológico , Antibacterianos/farmacología , Suplementos Dietéticos , Humanos , Alcohol Polivinílico , QuercetinaRESUMEN
This review intends to act as an overview of fructose malabsorption (FM) and its role in the aetiology of diseases including, but not limited to, irritable bowel syndrome (IBS) and infantile colic and the relationship between fructose absorption and the propagation of some cancers. IBS results in a variety of symptoms including stomach pains, cramps and bloating. Patients can be categorised into two groups, depending on whether the patients' experiences either constipation (IBS-C) or diarrhoea (IBS-D). FM has been proposed as a potential cause of IBS-D and other diseases, such as infantile colic. However, our knowledge of FM is limited by our understanding of the biochemistry related to the absorption of fructose in the small intestine and FM's relationship with small intestinal bacterial overgrowth. It is important to consider the dietary effects on FM and most importantly, the quantity of excess free fructose consumed. The diagnosis of FM is difficult and often requires indirect means that may result in false positives. Current treatments of FM include dietary intervention, such as low fermentable oligo-, di-, monosaccharides and polyols diets and enzymatic treatments, such as the use of xylose isomerase. More research is needed to accurately diagnose and effectively treat FM. This review is designed with the goal of providing a detailed outline of the issues regarding the causes, diagnosis and treatment of FM.
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Cólico , Síndrome del Colon Irritable , Síndromes de Malabsorción , Pruebas Respiratorias , Cólico/complicaciones , Fructosa , Humanos , Síndrome del Colon Irritable/diagnóstico , Síndrome del Colon Irritable/etiología , Síndrome del Colon Irritable/terapia , Síndromes de Malabsorción/diagnóstico , Síndromes de Malabsorción/etiología , Síndromes de Malabsorción/terapiaRESUMEN
Three-dimensional (3D) printing is a recent technology, which gives the possibility to manufacture personalised dosage forms and it has a broad range of applications. One of the most developed, it is the manufacture of oral solid dosage and the four 3DP techniques which have been more used for their manufacture are FDM, inkjet 3DP, SLA and SLS. This systematic review is carried out to statistically analyze the current 3DP techniques employed in manufacturing oral solid formulations and assess the recent trends of this new technology. The work has been organised into four steps, (1) screening of the articles, definition of the inclusion and exclusion criteria and classification of the articles in the two main groups (included/excluded); (2) quantification and characterisation of the included articles; (3) evaluation of the validity of data and data extraction process; (4) data analysis, discussion, and conclusion to define which technique offers the best properties to be applied in the manufacture of oral solid formulations. It has been observed that with SLS 3DP technique, all the characterisation tests required by the BP (drug content, drug dissolution profile, hardness, friability, disintegration time and uniformity of weight) have been performed in the majority of articles, except for the friability test. However, it is not possible to define which of the four 3DP techniques is the most suitable for the manufacture of oral solid formulations, because the selection is affected by different parameters, such as the type of formulation, the physical-mechanical properties to achieve. Moreover, each technique has its specific advantages and disadvantages, such as for FDM the biggest challenge is the degradation of the drug, due to high printing temperature process or for SLA is the toxicity of the carcinogenic risk of the photopolymerising material.
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Diabetes mellitus is one of the long-known chronic diseases. Today, over 400 million people have been diagnosed with diabetes, yet curing it is still a challenge. Over the decades, the approaches of treating diabetes mellitus have evolved and polymeric materials have played an integral part in developing and manufacturing anti-diabetic medications. However, injection of insulin remains a conventional therapy for the treatment of diabetes. Oral administration is generally the most preferred route; yet, physiological barriers lead to a challenge in the formulation development for oral delivery of antidiabetic peptide and protein drugs. This present review focuses on the role of different types of biodegradable polymers (e.g., synthetic and natural) that have been used to develop micro and nanoparticles based formulations for anti-diabetic drugs (Type 1 and Type 2) and how the various encapsulation strategies impact its therapeutic effect, including pharmacokinetics studies, drug release profiles, and efficacy of the encapsulated drugs. This review also includes studies of different dosage forms such as oral, nasal, inhalation, and sublingual for the treatment of diabetes that have been investigated using synthetic and natural biodegradable polymers in order to develop an alternative route to subcutaneous route for better control of serum glucose levels.
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Insulina/farmacocinética , Nanopartículas , Preparaciones Farmacéuticas , Polímeros/síntesis química , Administración Oral , Sistemas de Liberación de Medicamentos , Humanos , Insulina/administración & dosificación , Insulina/metabolismo , Polímeros/químicaRESUMEN
Conclusions from previously reported articles have revealed that many commonly used pharmaceutical excipients, known to be pharmacologically inert, show effects on drug transporters and/or metabolic enzymes. Thus, the pharmacokinetics (absorption, distribution, metabolism and elimination) of active pharmaceutical ingredients are possibly altered because of their transport and metabolism modulation from the incorporated excipients. The aim of this review is to present studies on the interaction of various commonly-used excipients on pre-systemic metabolism by CYP450 enzymes. Excipients such as surfactants, polymers, fatty acids and solvents are discussed. Based on all the reported outcomes, the most potent inhibitors were found to be surfactants and the least effective were organic solvents. However, there are many factors that can influence the inhibition of CYP450, for instance type of excipient, concentration of excipient, type of CYP450 isoenzyme, incubation condition, etc. Such evidence will be very useful in dosage form design, so that the right formulation can be designed to maximize drug bioavailability, especially for poorly bioavailable drugs.
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Excipientes/farmacología , Inactivación Metabólica/efectos de los fármacos , Preparaciones Farmacéuticas/metabolismo , Transportadoras de Casetes de Unión a ATP/efectos de los fármacos , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Sistema Enzimático del Citocromo P-450/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/metabolismo , Excipientes/farmacocinética , Humanos , Tasa de Depuración Metabólica/efectos de los fármacosRESUMEN
Since the FDA approval of Spritam, there has been a growing interest in the application of 3D printing in pharmaceutical science. 3D printing is a method of manufacturing involving the layer-by-layer deposition of materials to create a final product according to a digital model. There are various techniques used to achieve this method of printing including the SLS, SLA, FDM, SSE and PB-inkjet printing. In biomanufacturing, bone and tissue engineering involving 3D printing to create scaffolds, while in pharmaceutics, 3D printing was applied in drug development, and the fabrication of drug delivery devices. This paper aims to review the use of some 3D printing techniques in the fabrication of oral solid dosage forms. FDM, SLA SLS, and PB-Inkjet printing processes were found suitable for the fabrication of oral solid dosage forms, though a great deal of the available research was focused on fused deposition modelling due to its availability and flexibility. Process parameters as well as strategies to control the characteristics of printed dosage forms are analysed and discussed. The review also presents the advantages and possible limitations of 3D printing of medicines.
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Sistemas de Liberación de Medicamentos , Preparaciones Farmacéuticas , Impresión Tridimensional , Tecnología Farmacéutica , Formas de Dosificación , Medicina de PrecisiónRESUMEN
Patient to patient variability is one of the issues when administering medications to individuals with different health conditions, pharmacokinetic, age, fitness, gender, and race. This requires introducing smart and personalised drug delivery systems with controlled release profile manufactured using novel approaches. Additive manufacturing (AM) provides opportunities such as full customisation, design freedom, and on-site manufacturing, and materials recycling. As a result, the academic and industrial demand for additive manufacturing for drug delivery has been continuously increasing and showing impressive results for a wide range of products. This paper provides an extensive overview of AM technologies and their applications for drug delivery. The review discusses AM technologies including their working principles, processed materials, as well as current progress in drug delivery to produce personalized dosages for every patient with controlled release profile. AM potentials, industrial scale, and challenges are investigated with regards to practice and industrial applications. The paper covers novel possibilities of AM technologies and their pharmaceuticals applications, which indicate a promising healthcare future.
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Preparaciones Farmacéuticas/química , Tecnología Farmacéutica/métodos , Preparaciones de Acción Retardada/química , Sistemas de Liberación de Medicamentos/métodos , Humanos , Impresión TridimensionalRESUMEN
Quantitative analysis using proton NMR (1H qNMR) has been employed in various areas such as pharmaceutical analysis (e.g., dissolution study), vaccines, natural products analysis, metabolites, and macrolide antibiotics in agriculture industry. However, it is not routinely used in the quantification of saccharides in dry powder inhaler (DPI) formulations. The aim of this study was to develop a 1H NMR method for the quantification of saccharides employed in DPI formulations. Dry powders as DPI carriers were prepared by spray drying (SD) and spray freeze drying (SFD) using three saccharides: namely D-mannitol, D-sorbitol and D-(+)-sucrose. The calibration curves constructed for all three saccharides demonstrated linearity with R2 value of 1. The 1H qNMR method produced accurate (relative error %: 0.184-3.697) and precise data with high repeatability (RSD %: 0.517-3.126) within the calibration curve concentration range. The 1H qNMR method also demonstrated significant sensitivity with low values of limit of detection (0.058â¯mM for D-mannitol, 0.045â¯mM for D-(+)-sucrose, and 0.056â¯mM for D-sorbitol) and limit of quantitation (0.175â¯mM for D-mannitol, 0.135â¯mM for D-(+)-sucrose, and 0.168â¯mM for D-sorbitol). Pulmonary deposition via impaction experiments of the three saccharides was quantified using the developed method. It was found that SFD D-mannitol (68.99%) and SFD D-(+)-sucrose (66.62%) exhibited better delivered dose (total saccharide deposition in throat and all impactor stages) than SD D-mannitol (49.03%) and SD D-(+)-sucrose (57.70%) (pâ¯<â¯0.05). The developed 1H qNMR methodology can be routinely used as an analytical method to assess pulmonary deposition in impaction experiments of saccharides employed as carriers in DPI formulations.
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Inhaladores de Polvo Seco , Excipientes/química , Manitol/química , Sorbitol/química , Sacarosa/química , Adulto , Desecación , Liofilización , Humanos , Pulmón/metabolismo , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
OBJECTIVE: Intensive self-monitoring of blood glucose levels by patients with diabetes achieves optimal glucose control, hence reducing the likelihood of complications. METHODS: This is a prospective, cross-sectional study targeting adults with diabetes through community pharmacies and patient groups in Central and West London over a period of 10 weeks. RESULTS: In all, 195 adults with diabetes were included in the analysis of the results. When monitoring adherence was examined, 43.4% (n=33/76) of participants with type 1 diabetes reported that their health care professionals had asked them to monitor their blood glucose levels between 3 and 4 times per day; however, 10% of this group was not following their health-care professionals' directions. Participants with type 2 diabetes were asked the same question; 42.9% (n=51/119) were asked to monitor their blood glucose between 3 and 4 times a day, but only 2.5% (n=3/119) were following their health-care professionals' directions. When questioned about their reasons for poor adherence, the cohort indicated that it was due to the painful (29.2%, n=57/195), uncomfortable (33.8%, n=66/195) or inconvenient (36.9%, n=72/195) nature of testing. In addition, 75.3% (n=147/195) of the participants expressed their desire for a noninvasive monitoring device, and 74.3% (n=145/195) said they would be satisfied to use one of the preselected advanced technologies to monitor their blood glucose levels. CONCLUSIONS: The favoured advanced technology, selected by 49.7% (n=97/195) of participants, was the wristband. Statistical significance was seen between the type of diabetes and the device selected; patients with type 1 diabetes preferred contact lenses (p<0.05) and tattoos (p<0.0001), whereas participants with type 2 diabetes preferred earlobe sensors (p<0.0001) and saliva analyzers (p<0.0001). Participants' gender, age and ethnicity also influenced device selection.
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Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 2/sangre , Invenciones , Participación del Paciente , Percepción , Adulto , Automonitorización de la Glucosa Sanguínea/psicología , Automonitorización de la Glucosa Sanguínea/tendencias , Estudios Transversales , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/psicología , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/psicología , Femenino , Humanos , Londres/epidemiología , Masculino , Persona de Mediana Edad , Participación del Paciente/psicología , Estudios Prospectivos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Contact lenses (CLs) designed to deliver medication gradually to the eye are being developed and investigated for the use in ocular drug delivery. The aim of the current research is to determine patients' acceptance of the use of lenses for ocular drug delivery. In addition, the study aimed to seek the views and perceptions of healthcare professionals (HCPs) on CLs as a method of ocular drug delivery and whether it will be prescribed to treat ocular conditions. This was a cross-sectional survey targeted at patients and HCPs. Two separate questionnaires were created with open-closed ended and multiple response questions, gauging the perceptions and acceptance of CLs as drug delivery tool. The patients' survey was distributed in John Radcliffe (JR), Oxford and Moorfields eye hospital (MEH), London, UK. The HCPs' questionnaire was manually distributed and was also devised on Survey Monkey and sent by email to ophthalmologists, optometrists, opticians, GPs and hospital and community pharmacists. The data were analysed using SPSS statistical software and Excel. Over 60% (92/151) of patients would accept the use of CLs for their ocular treatment with the highest acceptance being reported by patients in the age group of 30-49 years old. The most frequently used conventional treatment formulation was eye drops as indicated by 87% (131/151) of the responses. More than half of eye drop users (57%, 75/131) indicated that they would accept using CLs expecting them to reduce the frequency of application of the medicine and be less time consuming. Interestingly, half of HCPs were not aware of CLs as an ocular drug delivery method; nevertheless, a total of 65 HCPs out of the 112 surveyed stated that they would prescribe/dispense CLs to treat ocular disease.
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Lentes de Contacto , Sistemas de Liberación de Medicamentos , Oftalmopatías/tratamiento farmacológico , Oftalmólogos/psicología , Optometristas/psicología , Aceptación de la Atención de Salud/psicología , Administración Oftálmica , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Encuestas de Atención de la Salud , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Oral modified-release multiparticulate dosage forms, which are also referred to as oral multiple-unit particulate systems, are becoming increasingly popular for oral drug delivery applications. The compaction of polymer-coated multiparticulates into tablets to produce a sustained-release dosage form is preferred over hard gelatin capsules. Moreover, multiparticulate tablets are a promising solution to chronic conditions, patients' adherence, and swallowing difficulties if incorporated into orodispersible matrices. Nonetheless, the compaction of multiparticulates often damages the functional polymer coat, which results in a rapid release of the drug substance and the subsequent loss of sustained-release properties. This review brings to the forefront key formulation variables that are likely to influence the compaction of coated multiparticulates into sustained-release tablets. It focusses on the tabletting of coated drug-loaded pellets, microparticles, and nanoparticles with a designated section on each. Furthermore, it explores the various approaches that are used to evaluate the compaction behaviour of particulate systems.
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Recently, there are growing demands in manufacturing of net shape micro parts for wide range of applications due to the increasing interest in miniaturization. In this paper, the fabrication of tetragonal phase zirconia/alumina (YSZ/Al2O3) nanocomposite micro-parts with high quality is presented. The fabrication process is based on soft lithography and colloidal powder dispersion. Experimental results showed that by optimizing the soft lithography and the dispersion process, it was possible to produce high-resolution micro-parts with well dispersed alumina. The X-ray diffraction results had confirmed the important role of the alumina particles in eliminating the emergence of monoclinic phase while the microstructures reveal a pure tetragonal phase. In addition, the sintered YSZ/Al2O3 micro parts achieved micro hardness with 20% superior to the pure YSZ sintered micro-parts with the addition of 5% alumina.
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The bacterial species Neisseria gonorrhoeae (N. gonorrhoeae) and Staphylococcus aureus (S. aureus) are amongst the main microorganisms that cause ophthalmia neonatorum. The current treatment involves the use of various antibiotics such as ciprofloxacin, cephalosporin, ceftriaxone and cefotaxime. However, this treatment strategy is becoming more ineffective due to the antibiotic resistance in N. gonorrhoeae. The current study explores the potential use of fatty acid based microemulsions (ME) to prevent N. gonorrhoeae and S. aureus infections in new-borns' eyes without harmful side effects such as corneal or conjunctiva irritation. Pseudo-ternary phase diagrams were constructed to evaluate microemulsion regions and six different α-linolenic acid based microemulsions were prepared. The prepared formulations were characterized for α-linolenic acid content, size, transparency, zeta potential, Polarized light Microscopy, antimicrobial activity and ex vivo ocular toxicity. The mean droplet size of the ME formulations was in the range of 190.4 to 350.5 nm and polydispersity index (PDI) values were in the range of 0.102 to 0.561. All formulations were found stable upon storage for at least 8 weeks. In addition, self-diffusion coefficients determined by nuclear magnetic resonance (NMR) reflected that the diffusability of water increased at higher than 30% w/w water, while that of fatty acids and surfactants was in reverse. The antimicrobial efficacy of microemulsions was determined against N. gonorrhoeae and S. aureus. It was concluded that all microemulsions have strong antimicrobial effects against N. gonorrhoeae and S. aureus. Finally, bovine corneal opacity permeability (BCOP) and hen's egg chorioallantoic (HET-CAM) tests results showed that all microemulsion formulations were not strong ocular irritants.
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In this study, solid dispersions of prednisolone (PRD) and bovine serum albumin (BSA) were prepared by spray drying and freeze drying methods using a PRD:BSA solution [20:1 molar ratio (MR)]. PRD-BSA dispersed mixtures were characterized by scanning electron microscopy (SEM), and powder X-ray diffraction (XRD), and differential scanning calorimetry (DSC). PRD-BSA physical and dispersed mixtures showed significantly higher solubility in water than that of unprocessed drug. Enhancement factor of six was obtained in both physical mixture and solid dispersion solubility studies. In-vitro dissolution and release studies under physiological conditions showed an immediate release of PRD from the solid dispersions, with almost 90% of the drug dissolved in the first 10 min. PRD was immediately released from BSA binding complex. This study demonstrates the potential for the use of BSA to enhance the solubility and dissolution rate, hence bioavailability, of the unionizable drugs.
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Antiinflamatorios/química , Portadores de Fármacos/química , Prednisolona/química , Albúmina Sérica Bovina/química , Animales , Antiinflamatorios/administración & dosificación , Rastreo Diferencial de Calorimetría , Bovinos , Desecación , Composición de Medicamentos , Liberación de Fármacos , Liofilización , Prednisolona/administración & dosificación , Solubilidad , Difracción de Rayos XRESUMEN
The fast development in materials science has resulted in the emergence of new pharmaceutical materials with superior physical and mechanical properties. Low-substituted hydroxypropyl cellulose is an ether derivative of cellulose and is praised for its multi-functionality as a binder, disintegrant, film coating agent and as a suitable material for medical dressings. Nevertheless, very little is known about the compaction behaviour of this polymer. The aim of the current study was to evaluate the compaction and disintegration behaviour of four grades of L-HPC namely; LH32, LH21, LH11, and LHB1. The macrometric properties of the four powders were studied and the compaction behaviour was evaluated using the out-of-die method. LH11 and LH22 showed poor flow properties as the powders were dominated by fibrous particles with high aspect ratios, which reduced the powder flow. LH32 showed a weak compressibility profile and demonstrated a large elastic region, making it harder for this polymer to deform plastically. These findings are supported by AFM which revealed the high roughness of LH32 powder (100.09 ± 18.84 nm), resulting in small area of contact, but promoting mechanical interlocking. On the contrary, LH21 and LH11 powders had smooth surfaces which enabled larger contact area and higher adhesion forces of 21.01 ± 11.35 nN and 9.50 ± 5.78 nN, respectively. This promoted bond formation during compression as LH21 and LH11 powders had low strength yield.
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Celulosa/análogos & derivados , Composición de Medicamentos , Celulosa/química , Fuerza Compresiva , Composición de Medicamentos/métodos , Elasticidad , Excipientes/química , Fenómenos Mecánicos , Porosidad , Polvos , Solubilidad , ComprimidosRESUMEN
There is an immense research interest to utilise contact lens (CLs) as a popular platform for ocular drug delivery. However, CLs are the major predisposing factors of bacterial keratitis which is commonly caused by adhesion of microbes such as Pseudomonas aeruginosa and Staphylococcus epidermidis. The aim of the current study is to explore the effect of surfactants; Poloxamer 188, Polysorbate 80 and Tetronic® 90R4 (at 0.25% - 3% v/v) on the characteristics of CLs and on the adhesion abilities of Pseudomonas aeruginosa to the lenses' surfaces. CLs were formulated using a hydrophilic monomer; 2-hydroxyethyl methacrylate (HEMA) together with silicone-based polymer such as Poly dimethyl siloxane (PDMS) or 3,3,3-trifluoropropylsilane (FSA) then lenses were polymerized under UV light. The formulated CLs with surfactants were found to have an increased equilibrium water content (EWC) due to hydrophilic moiety present in surfactants. A relationship was deduced between EWC and surface contact angle of lenses containing surfactants; where an increased EWC was associated with a decrease in contact angle reflecting a more hydrophilic surfaces of CLs. Apart from the 3% Polysorbate 80 (pâ¯<â¯.0001) CLs, all other formulations had light transmission values over 80%. Lenses with surfactants were found to have lower bacterial ATP concentration than lenses without surfactants. Poloxamer 188 in FSA lenses reduced bacterial adhesion from 4.22â¯×â¯10-4⯱â¯1.30â¯×â¯10-4 pM to 1.03â¯×â¯10-4⯱â¯4.86â¯×â¯10-5 pM, a reduction by 75.59% when compared to the control lenses (pâ¯=â¯.002). Moreover, 1% Tetronic® 90R4 in PDMS showed a reduction by 57.17% in ATP concentration. Polysorbate 80 in FSA exhibited the least bacterial adhesion with an average bacterial ATP concentration of 3.85â¯×â¯10-5⯱â¯2.61â¯×â¯10-5 pM; i.e 90.88% less bacterial ATP than control lenses (pâ¯=â¯.001). Bioluminescence studies demonstrated a decrease in Pseudomonas aeruginosa adhesion to CLs containing surfactants without impairing the optical and mechanical characteristics of the lenses.