Introduction: Methadone hydrochloride (MDN) is an effective pharmacological substitution treatment for opioids dependence, adopted in different countries as methadone maintenance treatment (MMT) programmes. However, MDN can exacerbate the addiction problem if it is abused and injected intravenously, and the frequent visits to the MMT centres can reduce patient compliance. The overall aim of this study is to develop a novel extended-release capsule of MDN using the sol-gel silica (SGS) technique that has the potential to counteract medication-tampering techniques and associated health risks and reduce the frequent visits to MMT centres. Methods: For MDN recrystallisation, a closed container method (CCM) and hot-stage method (HSM) were conducted, and MDN crystals were characterised using the polarised light microscope (PLM). MDN crystal thickness was determined by scanning electron microscopy (SEM) and confocal microscopy (CM) to establish a relationship between MDN crystals thickness and their birefringence colours using the Michel-Levy Birefringence Colour Chart. The experimental series was continued to produce novel silica-based MDN formulations A and B capsules by adding MDN powder at the end and beginning of the SGS process, respectively. The silica-based MDN formulations were characterised by Fourier transform infrared (FT-IR), SEM, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), PLM and mean grey value (MGV) analyses. The in vitro release studies (n=3) for the silica-based MDN formulations and pure MDN capsules were conducted in a phosphate buffer solution (pH= 7.2) for 7 days. Stability studies were conducted for 1 month by keeping the silica-based MDN capsules under 25°C and 57% RH. Results: The optimal method to produce large numbers of MDN crystals was the CCM, and MDN crystals were characterised as diamond shaped with an intrinsic angle of 62o. The SEM surpassed the CM in measuring MDN crystal thickness, and Mann-Whitney U Test showed statistically significant differences between SEM and confocal thickness measurements (U= 1283, p < 0.05) as the SEM exhibited thinner diamond crystals (6.62 ± 2.9 µm) than the CM measurements (9.6 ± 4.6µm). According to the Michel-Levey birefringence colour chart (using the SEM mean thickness of MDN crystals and their retardation value of 428 nm), most of MDN crystals demonstrated a yellow colour. The FT-IR, SEM, DSC, MGV and PLM analyses of both silica-based MDN formulations revealed that MDN was successfully incorporated inside the silica network producing amorphous material (with no appearance of the melting peak of pure MDN at 233.4°C) with evidence of no physical or chemical interaction between sol-gel silica and MDN. However, the TGA analysis revealed a significantly greater amount of MDN was loaded inside the silica-based MDN formulation B compared to A (t = 2.80, p = 0.009, n=6), as 28.3 ± 0.6 mg of MDN was loaded in the former while 25.6 ± 0.7 mg in the latter. In addition, the silica-based MDN formulation B released 10% more MDN after 7 days than formulation A, and both formulations were stable when stored for 1 month under 57% RH and 25°C. Conclusion: The novel combined use of SEM and PLM techniques shows a potential for the identification of MDN in forensic science as it established a range of birefringence colours of MDN crystals. Moreover, the new silica-based MDN formulation B can help to deter MDN abuse and increase patient adherence to MMT due to its potential to sustain MDN release and reduce the frequent visits to MDN treatment centres.
Sol-gel derived CuCo-oxide coatings as solar selective surfaces, synthesized onto aluminium substrates at various annealing temperatures, are analysed by correlating their structural, chemical bonding states, and surface morphological topographies. As the annealing progressed, all the coatings displayed a Cu0.56Co2.44O4 (ICSD 78-2175) phase with preferential orientation along (400) reflection plane. Rietveld refinement of X-ray diffraction (XRD) data indicate that residual stress and microstrains developed around the coating surfaces are reduced resulting in mechanically stable thin films. Enhancement of the crystallite size and preferred orientation of the surface were confirmed via XRD, field emission scanning electron microscopy (FESEM),
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Sumatriptan(ST) is a selective agonist at serotonin 5-HTI receptors, as well as 5-HT1B/1D subtypes. It is effective for acute migraine attacks, but has a short half life (about 2 hours) and low oral bioavailability (15%). The purpose of this study was to develop and optimize nasal mucoadhesive in-situ gel(IG) of ST to enhance nasal residence time for migraine management. Cold method was used to prepare different formulas of ST nasal IG, using thermosensitive polymers (poloxamer 407 alone or with poloxamer 188) with a mucoadhesive polymer hyaluronic acid (HA) which were examined for gelation temperature and gelation time, pH, drug content, gel strength, spreadability, muc
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Silybum marianum, from which silymarin (SM) is extracted, is a medicinal herb. In the Biopharmaceutics Classification System, it is of the class II type, meaning it is almost completely insoluble in water. It has a number of therapeutic properties, including anti-inflammatory as well as properties that promote wound healing.
This research target is to promote the dissolution and solubility of SM by employing a technique called solid dispersion and then incorporating the formula of solid dispersion into a topical gel that can be used for wound healing.
Solid dispersion is a technique used to enhance solubility and dissolve pharmaceuticals that are not water-soluble. This method is widely used because of its low cos
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Background: Meclizine hydrochloride (MCZ) is an antihistamine that is used as an antiemetic to prevent and cure nausea and vomiting. Because of its limited water solubility and first-pass metabolism, it exhibits variable absorption. Objective: To formulate and evaluate MCZ as an intranasal in situ gel with increased residence time and permeability. Methods: We made an inclusion complex of MCZ using various cyclodextrins as a complexing agent to help the drug dissolve better. The complexes were studied, and the ones that were better at dissolving were chosen to be used in the creation of an in situ gel with poloxamer 407 (17–20% w/v) and hyaluronic acid (0.25–0.75% w/v). Prepared formulas were subjected to various evaluation tes
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Ondansetron hydrochloride (ONH) is a very bitter, potent antiemetic drug used for the treatment and/or prophylaxis of chemotherapy or radiotherapy or postoperative induced emesis. The objective of this study is to formulate and evaluate of taste masked fast dissolving tablet (FDTs) of ONH to increase patient compliance.
ONH taste masked granules were prepared by solid dispersion technique using Eudragit E100 polymer as an inert carrier. Solvent evaporation and fusion melting methods were used for such preparation.
Completely taste masking with zero release of drug in phosphate buffer pH 6.8was obtained from granules prepared by solvent evaporation method using drug: polymer ratio of 1:2, from which four formulas pas
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The effect of using different R -molar ratio under variable reaction conditions (acidic as well as basic environment and reaction temperature) have been studied. The overall experiments are driven with open and closed systems. The study shows that there is an optimum value for a minimum gelling time at R equal 2. The gelling time for all studied open system found to be shorter than in closed system. In acidic environment and when R value increased from 2 to 10, the gelling time of closed systems has increased four times than open systems at T=30 ?C and fourteen times when temperature reaction increased to 60 ?C. While in basic environment the influence of increasing R value was limited.
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