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The main objective of this research was to create and evaluate the efficacy of orally disintegrating tablets containing sumatriptan succinate at a dosage of 25 milligrammes, a medicine commonly prescribed for the treatment of migraines. The tablets are made using the direct compression method. In order to achieve best results, the formulations were enriched with microcrystalline cellulose of varying composition (Avicel PH 102), mannitol as a diluent, crospovidone, croscaramellose, and sodium starch glycollate as superdisintegrants. Carbomer (carbopol 940), Sodium CMC, and Sodium Alginate were among the other excipients that were used. When used at varying doses, these excipients act as disintegrants. In addition, magnesium stearate was used as a substance to reduce friction, while talc was used as a substance to improve flow. We assessed each of the excipients to ascertain their compatibility with the model drug. The findings revealed no occurrence of any physical or chemical interaction. Before compression, the preformulation features of the tablet blend were examined. The criteria considered were bulk density, tapped density, compressibility index, and hausner ratio. An assessment was carried out on central tablets to ascertain their dimensions, firmness, tendency to crumble, variability in weight, rate of disintegration, and uniformity of drug content properties. Furthermore, an investigation was conducted to examine the impact of these variables on the release of the drug. The drug release studies were performed in vitro using the USP dissolving apparatus-II (paddle type) with a phosphate buffer solution at a pH of 6.8. The experiments were conducted at a speed of 50 revolutions per minute at a temperature of 37 degrees Celsius, with a standard deviation of 5 degrees Celsius. The sampling was conducted at consistent intervals of 2, 4, 6, 8, and 10 minutes. After each withdrawal, an equivalent volume of dissolving medium was replaced with the sample. The ultravio

The main objective of this research was to create and evaluate the efficacy of orally disintegrating tablets containing sumatriptan succinate at a dosage of 25 milligrammes, a medicine commonly prescribed for the treatment of migraines. The tablets are made using the direct compression method. In order to achieve best results, the formulations were enriched with microcrystalline cellulose of varying composition (Avicel PH 102), mannitol as a diluent, crospovidone, croscaramellose, and sodium starch glycollate as superdisintegrants. Carbomer (carbopol 940), Sodium CMC, and Sodium Alginate were among the other excipients that were used. When used at varying doses, these excipients act as disintegrants. In addition, magnesium stearate was used as a substance to reduce friction, while talc was used as a substance to improve flow. We assessed each of the excipients to ascertain their compatibility with the model drug. The findings revealed no occurrence of any physical or chemical interaction. Before compression, the preformulation features of the tablet blend were examined. The criteria considered were bulk density, tapped density, compressibility index, and hausner ratio. An assessment was carried out on central tablets to ascertain their dimensions, firmness, tendency to crumble, variability in weight, rate of disintegration, and uniformity of drug content properties. Furthermore, an investigation was conducted to examine the impact of these variables on the release of the drug. The drug release studies were performed in vitro using the USP dissolving apparatus-II (paddle type) with a phosphate buffer solution at a pH of 6.8. The experiments were conducted at a speed of 50 revolutions per minute at a temperature of 37 degrees Celsius, with a standard deviation of 5 degrees Celsius. The sampling was conducted at consistent intervals of 2, 4, 6, 8, and 10 minutes. After each withdrawal, an equivalent volume of dissolving medium was replaced with the sample. The ultravio

Measuring the radial flow velocity field of yield stress fluids (YSFs) between two parallel disks provides crucial data to understand the underlying flow phenomena. However, direct velocimetry of YSFs in the radial flow configuration remains a challenge, due to the complex fluid rheology and geometry constraints. In this paper, we present an experimental device for measuring YSF radial flow velocity profiles. Ultrasound Velocity Profiling (UVP) is used to non-intrusively measure the velocity profiles. The Tikhonov regularization method is implemented to obtain smooth velocity profiles, which are used to calculate the plug-flow region. Compared to our previous work on radial flow, the current contributions include: (i) additional structural frame members to maintain a constant aperture, (ii) wall slip reduction, and (iii) an improved velocity profile plug-detection algorithm. The results show that the experimental device and the measurement method are effective for further studying radial flow behavior of YSFs for industrial applications., Not duplicate with DiVA 1606821 which is an accepted manuscript.QC 20211215

The extensive use of oral dosage forms for the treatment of diseases may be linked to deficient pharmacokinetic properties. In some cases the drug is barely soluble; in others, the rapid transit of the formulation through the gastrointestinal tract (GIT) makes it difficult to achieve therapeutic levels in the organism; moreover, some drugs must act locally due to a gastric pathology, but the time they remain in the stomach is short. The use of formulations capable of improving all these parameters, as well as increasing the resident time in the stomach, has been the target of numerous research works, with low-density systems being the most promising and widely explored, however, there is further scope to improve these systems. There are a vast variety of polymeric materials used in low-density gastroretentive systems and a number of methods to improve the bioavailability of the drugs. This works aims to expedite the development of breakthrough approaches by providing an in-depth understanding of the polymeric materials currently used, both natural and synthetic, their properties, advantages, and drawbacks

The extensive use of oral dosage forms for the treatment of diseases may be linked to deficient pharmacokinetic properties. In some cases the drug is barely soluble; in others, the rapid transit of the formulation through the gastrointestinal tract (GIT) makes it difficult to achieve therapeutic levels in the organism; moreover, some drugs must act locally due to a gastric pathology, but the time they remain in the stomach is short. The use of formulations capable of improving all these parameters, as well as increasing the resident time in the stomach, has been the target of numerous research works, with low-density systems being the most promising and widely explored, however, there is further scope to improve these systems. There are a vast variety of polymeric materials used in low-density gastroretentive systems and a number of methods to improve the bioavailability of the drugs. This works aims to expedite the development of breakthrough approaches by providing an in-depth understanding of the polymeric materials currently used, both natural and synthetic, their properties, advantages, and drawbacks

The extensive use of oral dosage forms for the treatment of diseases may be linked to deficient pharmacokinetic properties. In some cases the drug is barely soluble; in others, the rapid transit of the formulation through the gastrointestinal tract (GIT) makes it difficult to achieve therapeutic levels in the organism; moreover, some drugs must act locally due to a gastric pathology, but the time they remain in the stomach is short. The use of formulations capable of improving all these parameters, as well as increasing the resident time in the stomach, has been the target of numerous research works, with low-density systems being the most promising and widely explored, however, there is further scope to improve these systems. There are a vast variety of polymeric materials used in low-density gastroretentive systems and a number of methods to improve the bioavailability of the drugs. This works aims to expedite the development of breakthrough approaches by providing an in-depth understanding of the polymeric materials currently used, both natural and synthetic, their properties, advantages, and drawbacks

The extensive use of oral dosage forms for the treatment of diseases may be linked to deficient pharmacokinetic properties. In some cases the drug is barely soluble; in others, the rapid transit of the formulation through the gastrointestinal tract (GIT) makes it difficult to achieve therapeutic levels in the organism; moreover, some drugs must act locally due to a gastric pathology, but the time they remain in the stomach is short. The use of formulations capable of improving all these parameters, as well as increasing the resident time in the stomach, has been the target of numerous research works, with low-density systems being the most promising and widely explored, however, there is further scope to improve these systems. There are a vast variety of polymeric materials used in low-density gastroretentive systems and a number of methods to improve the bioavailability of the drugs. This works aims to expedite the development of breakthrough approaches by providing an in-depth understanding of the polymeric materials currently used, both natural and synthetic, their properties, advantages, and drawbacks

The extensive use of oral dosage forms for the treatment of diseases may be linked to deficient pharmacokinetic properties. In some cases the drug is barely soluble; in others, the rapid transit of the formulation through the gastrointestinal tract (GIT) makes it difficult to achieve therapeutic levels in the organism; moreover, some drugs must act locally due to a gastric pathology, but the time they remain in the stomach is short. The use of formulations capable of improving all these parameters, as well as increasing the resident time in the stomach, has been the target of numerous research works, with low-density systems being the most promising and widely explored, however, there is further scope to improve these systems. There are a vast variety of polymeric materials used in low-density gastroretentive systems and a number of methods to improve the bioavailability of the drugs. This works aims to expedite the development of breakthrough approaches by providing an in-depth understanding of the polymeric materials currently used, both natural and synthetic, their properties, advantages, and drawbacks

In the past few decades, considerable attention has been focused on the development of new drug delivery system (NDDS). The NDDS should ideally fulfill two prerequisites. Firstly, it should deliver the drug at a rate directed by the needs of the body, over the period of treatment. Secondly, it should channel the active entity to the site of action. Conventional dosage forms including prolonged release dosage forms are unable to meet none of these. At present, no available drug delivery system behaves ideally, but sincere attempts have been made to achieve them through various novel approaches in drug delivery. The aim of present work is to develop a niosomal drug delivery system of aceclofenac. To perform drug-polymer compatibility FT-IR studies were carried out and observed that there was no interaction between the APl and excipients. 8 niosomal formulations are prepared by the thin film hydration method using the cholesterol as the phospholipid. Prepared niosomal formulations were characterized by vesicle size, shape, surface charge, entrapment efficiency, drug content and invitro drug release studies. The vesicle size, size distribution and zeta potential of the optimized formulation (F5) was found to be 65.6 nm and zeta potential was found to be -1.5mV. Size distribution curve confirms the normal size distribution of the vesicles. The % entrapment efficiency of niosomal vesicles formulations were found to be in the range of 54.18±0.59 to 92.71±0.56 and optimized formulation was found to be 92.71±0.56 and drug content of niosomes formulations (F1to F8) were determined to be in the range of 94.6 -97.8%. The pH of all topical niosomal gels were found to be in the range of 7.4±0.02 to 7.4±0.08.The best fit with higher correlation (r2> 0.99) was found with the Zero Order Release and follows Korsemeyer peppas equation for all the formulations, which means that release of Aceclofenac from the lipid bilayer vesicles were due to diffusion. The stability studies were c

In the past few decades, considerable attention has been focused on the development of new drug delivery system (NDDS). The NDDS should ideally fulfill two prerequisites. Firstly, it should deliver the drug at a rate directed by the needs of the body, over the period of treatment. Secondly, it should channel the active entity to the site of action. Conventional dosage forms including prolonged release dosage forms are unable to meet none of these. At present, no available drug delivery system behaves ideally, but sincere attempts have been made to achieve them through various novel approaches in drug delivery. The aim of present work is to develop a niosomal drug delivery system of aceclofenac. To perform drug-polymer compatibility FT-IR studies were carried out and observed that there was no interaction between the APl and excipients. 8 niosomal formulations are prepared by the thin film hydration method using the cholesterol as the phospholipid. Prepared niosomal formulations were characterized by vesicle size, shape, surface charge, entrapment efficiency, drug content and invitro drug release studies. The vesicle size, size distribution and zeta potential of the optimized formulation (F5) was found to be 65.6 nm and zeta potential was found to be -1.5mV. Size distribution curve confirms the normal size distribution of the vesicles. The % entrapment efficiency of niosomal vesicles formulations were found to be in the range of 54.18±0.59 to 92.71±0.56 and optimized formulation was found to be 92.71±0.56 and drug content of niosomes formulations (F1to F8) were determined to be in the range of 94.6 -97.8%. The pH of all topical niosomal gels were found to be in the range of 7.4±0.02 to 7.4±0.08.The best fit with higher correlation (r2> 0.99) was found with the Zero Order Release and follows Korsemeyer peppas equation for all the formulations, which means that release of Aceclofenac from the lipid bilayer vesicles were due to diffusion. The stability studies were c

In the past few decades, considerable attention has been focused on the development of new drug delivery system (NDDS). The NDDS should ideally fulfill two prerequisites. Firstly, it should deliver the drug at a rate directed by the needs of the body, over the period of treatment. Secondly, it should channel the active entity to the site of action. Conventional dosage forms including prolonged release dosage forms are unable to meet none of these. At present, no available drug delivery system behaves ideally, but sincere attempts have been made to achieve them through various novel approaches in drug delivery. The aim of present work is to develop a niosomal drug delivery system of aceclofenac. To perform drug-polymer compatibility FT-IR studies were carried out and observed that there was no interaction between the APl and excipients. 8 niosomal formulations are prepared by the thin film hydration method using the cholesterol as the phospholipid. Prepared niosomal formulations were characterized by vesicle size, shape, surface charge, entrapment efficiency, drug content and invitro drug release studies. The vesicle size, size distribution and zeta potential of the optimized formulation (F5) was found to be 65.6 nm and zeta potential was found to be -1.5mV. Size distribution curve confirms the normal size distribution of the vesicles. The % entrapment efficiency of niosomal vesicles formulations were found to be in the range of 54.18±0.59 to 92.71±0.56 and optimized formulation was found to be 92.71±0.56 and drug content of niosomes formulations (F1to F8) were determined to be in the range of 94.6 -97.8%. The pH of all topical niosomal gels were found to be in the range of 7.4±0.02 to 7.4±0.08.The best fit with higher correlation (r2> 0.99) was found with the Zero Order Release and follows Korsemeyer peppas equation for all the formulations, which means that release of Aceclofenac from the lipid bilayer vesicles were due to diffusion. The stability studies were c

An evolution of distribution and orientation of fibres in the fibre reinforced self-compacting concrete during the casting process is an important matter as the final orientation and distribution of fibres can significantly influence mechanical properties of the structural elements. A two-way coupled model for flow of suspension of rigid solid particles in a non-Newtonian fluid with a free surface has been developed for such a purpose and is shortly presented in this paper. Several experiments using an apparent yield stress fluid, i.e. Carbopol® Ultrez 21 Polymer transparent gel, were conducted and analysed by means of digital image analysis. Orientation tensor fields coming from the digital image analysis were compared with the simulation to verify the ability of the model to properly represent the flow of the fibre reinforced self-compacting concrete.

An evolution of distribution and orientation of fibres in the fibre reinforced self-compacting concrete during the casting process is an important matter as the final orientation and distribution of fibres can significantly influence mechanical properties of the structural elements. A two-way coupled model for flow of suspension of rigid solid particles in a non-Newtonian fluid with a free surface has been developed for such a purpose and is shortly presented in this paper. Several experiments using an apparent yield stress fluid, i.e. Carbopol® Ultrez 21 Polymer transparent gel, were conducted and analysed by means of digital image analysis. Orientation tensor fields coming from the digital image analysis were compared with the simulation to verify the ability of the model to properly represent the flow of the fibre reinforced self-compacting concrete.

Drug delivery to the nasal and ocular mucosa faces several obstacles. One of these is from the effective clearance mechanisms present in the nose and eye. Polymer gels with suitable rheological properties can facilitate the absorption of poorly absorbed drugs by increasing the contact time of the drug with the mucosa. This has been attributed to the rheological and mucoadhesive properties of the gel. The main objective of this thesis was to investigate the importance of these features for the anticipated in vivo contact time, here exemplified by the ocular and nasal routes of administration. The in situ gelling polymer gellan gum was found to have a favourable rheological and in vivo performance. When administered in the nasal cavity of rats, a gel was formed that could remain at the site of administration for up to 4 hours. In addition, the epithelial uptake and transfer of a 3 kDa fluorescein dextran was higher than for a mannitol solution. Therefore, it was concluded that a gellan gum formulation should be a promising strategy for nasal drug delivery. The potential mucoadhesive properties of a variety of polymer gels were investigated using a rheological method and by measuring the tensile force required to detach the gel from a mucosa. With both methods the rheological properties of the gel were a determining factor for the results obtained. The rheological method was found to have several limitations. One of these was that a positive response, interpreted as mucoadhesion, was only seen with weak gels. The tensile method could, in contrast, detect strengthening of the mucus only for strong gels. However, this method reflects the in vivo performance of the gel better than the rheological method. Finally, dielectric spectroscopy was explored as a tool for investigating the likelihood of intimate surface contact between the gel and the mucus layer. This novel approach involved determining the ease with which a charged particle can pass the gel-mucus interface layer

Drug delivery to the nasal and ocular mucosa faces several obstacles. One of these is from the effective clearance mechanisms present in the nose and eye. Polymer gels with suitable rheological properties can facilitate the absorption of poorly absorbed drugs by increasing the contact time of the drug with the mucosa. This has been attributed to the rheological and mucoadhesive properties of the gel. The main objective of this thesis was to investigate the importance of these features for the anticipated in vivo contact time, here exemplified by the ocular and nasal routes of administration. The in situ gelling polymer gellan gum was found to have a favourable rheological and in vivo performance. When administered in the nasal cavity of rats, a gel was formed that could remain at the site of administration for up to 4 hours. In addition, the epithelial uptake and transfer of a 3 kDa fluorescein dextran was higher than for a mannitol solution. Therefore, it was concluded that a gellan gum formulation should be a promising strategy for nasal drug delivery. The potential mucoadhesive properties of a variety of polymer gels were investigated using a rheological method and by measuring the tensile force required to detach the gel from a mucosa. With both methods the rheological properties of the gel were a determining factor for the results obtained. The rheological method was found to have several limitations. One of these was that a positive response, interpreted as mucoadhesion, was only seen with weak gels. The tensile method could, in contrast, detect strengthening of the mucus only for strong gels. However, this method reflects the in vivo performance of the gel better than the rheological method. Finally, dielectric spectroscopy was explored as a tool for investigating the likelihood of intimate surface contact between the gel and the mucus layer. This novel approach involved determining the ease with which a charged particle can pass the gel-mucus interface layer

Drug delivery to the nasal and ocular mucosa faces several obstacles. One of these is from the effective clearance mechanisms present in the nose and eye. Polymer gels with suitable rheological properties can facilitate the absorption of poorly absorbed drugs by increasing the contact time of the drug with the mucosa. This has been attributed to the rheological and mucoadhesive properties of the gel. The main objective of this thesis was to investigate the importance of these features for the anticipated in vivo contact time, here exemplified by the ocular and nasal routes of administration. The in situ gelling polymer gellan gum was found to have a favourable rheological and in vivo performance. When administered in the nasal cavity of rats, a gel was formed that could remain at the site of administration for up to 4 hours. In addition, the epithelial uptake and transfer of a 3 kDa fluorescein dextran was higher than for a mannitol solution. Therefore, it was concluded that a gellan gum formulation should be a promising strategy for nasal drug delivery. The potential mucoadhesive properties of a variety of polymer gels were investigated using a rheological method and by measuring the tensile force required to detach the gel from a mucosa. With both methods the rheological properties of the gel were a determining factor for the results obtained. The rheological method was found to have several limitations. One of these was that a positive response, interpreted as mucoadhesion, was only seen with weak gels. The tensile method could, in contrast, detect strengthening of the mucus only for strong gels. However, this method reflects the in vivo performance of the gel better than the rheological method. Finally, dielectric spectroscopy was explored as a tool for investigating the likelihood of intimate surface contact between the gel and the mucus layer. This novel approach involved determining the ease with which a charged particle can pass the gel-mucus interface layer

Drug delivery to the nasal and ocular mucosa faces several obstacles. One of these is from the effective clearance mechanisms present in the nose and eye. Polymer gels with suitable rheological properties can facilitate the absorption of poorly absorbed drugs by increasing the contact time of the drug with the mucosa. This has been attributed to the rheological and mucoadhesive properties of the gel. The main objective of this thesis was to investigate the importance of these features for the anticipated in vivo contact time, here exemplified by the ocular and nasal routes of administration. The in situ gelling polymer gellan gum was found to have a favourable rheological and in vivo performance. When administered in the nasal cavity of rats, a gel was formed that could remain at the site of administration for up to 4 hours. In addition, the epithelial uptake and transfer of a 3 kDa fluorescein dextran was higher than for a mannitol solution. Therefore, it was concluded that a gellan gum formulation should be a promising strategy for nasal drug delivery. The potential mucoadhesive properties of a variety of polymer gels were investigated using a rheological method and by measuring the tensile force required to detach the gel from a mucosa. With both methods the rheological properties of the gel were a determining factor for the results obtained. The rheological method was found to have several limitations. One of these was that a positive response, interpreted as mucoadhesion, was only seen with weak gels. The tensile method could, in contrast, detect strengthening of the mucus only for strong gels. However, this method reflects the in vivo performance of the gel better than the rheological method. Finally, dielectric spectroscopy was explored as a tool for investigating the likelihood of intimate surface contact between the gel and the mucus layer. This novel approach involved determining the ease with which a charged particle can pass the gel-mucus interface layer

Two gentamicin-containing hydrogels of different water solubility have been prepared using Carbopol as a thickening agent. The most insoluble hydrogel (A) released its drug content extremely slowly, regardless of the absence or presence of plasma. In contrast, the rate of drug release from hydrogel B was just slightly slower than the free drug in saline, whereas in the presence of plasma components just 35% of the gentamicin contained in hydrogel B was eventually released from it. Pharmacokinetic studies showed a sustained release of gentamicin from the Carbopol hydrogel (B), with an elimination half-life in excess of 2.5 h.

Decontaminants for several toxic missile propellants were evaluated and recommendations were made for the most suitable materials. The investigation was conducted in two phases. Phase I, a practical study of the propellants, consisted of a compilation of information pertaining to general properties, decontamination procedures and toxicity data based on a literature review. The materials thus investigated were fluorine, hydrazine, nitrogen tetroxide, hydrogen, light metal hydrides, beryllizine, Compound A, mixed hydrazine fuels, alumizine and UDMH. Phase II, a laboratory investigation, involved the experimental evaluation of candidate decontaminants. This work, together with a theoretical evaluation of decontaminants based on the practical study, involved four propellants: Compound A, mixed hydrazine fuels (MHF-3 and MHF-5) and alumizine.

Precision dilatometer experiments have shown that very significant improvements in gel stability - one order of magnitude - can be achieved by using high purity ingredients. Unique nonadhesive gellants previously discovered in this program likewise improve stability with a variety of solid fuel additives. Nonadhesive gels cannot be characterized by some of the existing procedures, however flow rheograms and centrifuge tests have confirmed that the new gellants are superior. (Author)

The long-term storability of hydrazine-aluminum gelled propellants is uncertain due to propellant decomposition. The problem was investigated in three phases: (1) bulk expansion due to gases trapped in the gel; (2) pressure rise due to gas evolution and bulk expansion of the propellant; and (3) scaling tests to determine the effect of size on gas evolution rate as measured by pressure rise. Nine chemicals were tested as additives for reducing gas evolution. None lowered the rate significantly below that of the hydrazine control, but two, toluene and silicon dioxide, were selected for trial in the scaling tests. These tests, even without inhibitor, showed a marked decrease of gas evolution rate with increasing size. When extrapolated to 10,000 gal., the gas evolution rate is of the order of 10 to the -6th power sccm/lb-minute. Before these extrapolated results are accepted, it is recommended that further work be accomplished using larger test containers to confirm the scaling effect. (Author)

The stability of aluminized hydrazine gels was studied using a sensitive dilatometer. The influence of minor constituents on chemical instability showed that certain trace contaminants are deleterious. A study of new gelling agents possessing bettwe flow characteristics is continuing. Pressure cycling vibration and acceleration testing has been carried out on candidate gels. A modified rheometer has been selected as the best method for cyclic testing of gels. A modified ring tensiometer has been constructed to measure the adhesive forces of gels.

This report summarizes the efforts on continued stability testing of aluminum-hydrazine-carbopol combinations and preparation for formulation and characterization of liquid metalized propellants containing LM-2 and LMH-2. It also summarizes the analytical and experimental investigation of the N2H4/N2O4 propellant system which was undertaken to determine its reaction kinetics at rocket chamber conditions. The background atmospheric flame studies on H2/NO2 and NH3/O2 are complete and the results are reported. Also reported is the engine performance (characteristic velocity C) of the liquid-liquid combustor and the preliminary reaction mechanism for the N2H4/N2O4 propellant system. Preliminary background information is given on a heat-of-formation study on XeF6. (Author)

Herstellung von Gelkombinationen aus Clotrimazol und Xanthan zur vaginalen Anwendung. Es wurden Mukadhäsionstest und Wirkstofffreisetzungstest durchgeführt sowie Pilztests, bei denen dann Canesten als Referenz diente., von Magdalena Haug, Diplomarbeit Universität Innsbruck 2018