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Functionalization of Upsalite® with TiO2 for UV-blocking applications / Funktionalisering av Upsalite® med TiO2 för UV-skyddande applikationerNotfors, Celina January 2016 (has links)
Inorganic UV-filters in use today often occur as nanoparticles and have a photocatalytic effect, which can be a problem since they can cause negative health effects. This is why Upsalite®, a mesoporous magnesium carbonate recently has been investigated as a UV-filter. Upsalite® itself is however not suitable as a UV-filter since it mainly protects in the UVC range and hence it needs to be complemented by other substances. The substance studied to functionalize Upsalite® in this thesis is titanium dioxide which is an inorganic UV-filter commonly used in sunscreens. In this work two different sol-gel synthesis routes of titanium dioxide have been investigated as well as a co-synthesis of Upsalite® and titanium dioxide. In the first synthesis route already synthesized Upsalite® was mixed with titanium tetra-isopropoxide and 1-propanol. The second synthesis route was a modified version of synthesis routes described in literature where methanol solvent was used and the pressure was altered by CO2. This route was explored due to its resemblance with the Upsalite® synthesis. Pressure, temperature and amount of water were varied to optimize incorporation of Upsalite® and investigate possibilities for a co-synthesis. Subsequently a co-synthesis of Upsalite® and titanium dioxide was performed that resulted in two amorphous composite materials depending on if water was added in the drying procedure or not. When mixing Upsalite® in the synthesis liquid of titanium dioxide, titanium dioxide seems to be deposited on Upsalite®. It is however difficult to determine whether the pores of Upsalite® have been completely filled or if they have collapsed. The acid catalyst HCl promotes formation to crystalline titanium dioxide but Upsalite® instead prevents it. The limited crystallization of titanium dioxide when synthesized with Upsalite® may be due to confinement in the Upsalite® pores. The UV-blocking properties of the TiO2-Upsalite® without HCl are good with an sun protection factor (SPF) of 27 for a 10 wt% blend in a lotion and an SPF of 7 for the sample with HCl. The modified synthesis route of TiO2 showed that it is possible to perform a sol-gel synthesis with a considerably lower amount of water than found in literature and that alteration of temperature and pressure during the synthesis does not affect the crystallization temperature noteworthy. The materials obtained from the co-synthesis are slightly porous, probably consisting of one or several magnesium titanium oxides and a carbonate phase and showed a transmission cutoff in between Upsalite® and titanium dioxide corresponding to an SPF of 5.
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Functionalization of Upsalite® by aminosilane deposition from gas phaseGrahn, Alexander January 2016 (has links)
The use of desiccant materials is crucial in many applications, such as dehumidification rotors, in OLED screen and as desiccant materials in dish washers, for example. Upsalite® is a novel, anhydrous, micro-mesoporous, and large surface area structure consisting of amorphous magnesium carbonate which has been shown to exhibit a good water sorption capacity. Depending on the heat treatment of Upsalite® after synthesis, the material exhibits different sorption capacity and hydrolytic stability. Calcined Upsalite® has a higher sorption capacity compared to as-synthesized, but crystallizes into nesquehonite when stored in a relative humidity of 100 % for several days. The need to stabilize the material arises and the use of two different aminosilanes as surface stabilizers has been evaluated. Two different deposition techniques from gas phase have been used, atomic layer deposition and vapor phase grafting, which are evaluated and compared. The results of the functionalization show an increase in decomposition temperature by ~25 °C of the functionalized materials compared to non-functionalized. The initial water sorption capacity of the functionalized material increases by up to 80 %, when stored in a relative humidity of 100 % for 24 h and shows a stabilizing effect after five cycles of repeated exposure to high humidity. The long term stability seems to have decreased due to pore collapse, when the functionalized material is cycled 5 times for one week in a repeated relative humidity of 100 %. The stability of the material when exposed to two liquids of different pH was also evaluated and the functionalized material exhibits a slower increase of the pH in the buffer solution, implying a retardation of Upsalite® dissolution. The conclusion is that a functionalization of the material with aminosilane increases the initial sorption capacity and has a stabilizing effect.
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Heavy metal removal and water treatment using UpsaliteErenbo, Philip January 2017 (has links)
Ion exchange reactions between Upsalite, a mesoporous magnesium carbonate, and metal ions of cadmium, lead and nickel have been studied to evaluate the capacities of Upsalite as a water treatment agent. Uptake capacity and reaction kinetics have been evaluated using a batch experiment and atomic absorption spectroscopy. Post reaction materials from the reaction between Upsalite and each of the three metal ions have been investigated with XRD, SEM and TGA in order to determine what species have been formed during the ion exchange. The maximum uptake capacity of Upsalite was found to be 990 mg/g for cadmium ions and 470 mg/g for nickel ions. The evaluation of the uptake capacity of lead ions in Upsalite was not conclusive but the results indicate a maximum uptake capacity of at least 4400 mg/g. The uptake capacity for lead ions is to high be explained by ion exchange alone and is proposed to be from both ion exchange and adsorption. The reaction between Upsalite and cadmium ions resulted in the formation of crystalline CdCO3 (Otavite) with some parts of MgCO3 and crystalline MgO remaining from the original material. Post reaction materials from the reaction between nickel ions and Upsalite were found to be amorphous and contained both MgCO3 and crystalline MgO. The reaction between Upsalite and lead ions resulted in crystalline hydrocerussite (Pb3(CO3)2(OH)2).
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Novel Hybrid Nanomaterials : Combining Mesoporous Magnesium Carbonate with Metal-Organic FrameworksSanderyd, Viktor January 2018 (has links)
Nanotechnology as a field has the potential to answer some of the major challenges that mankind faces in regards to environmental sustainability, energy generation and health care. Though, solutions to these concerns can not necessarily rely on our current knowhow. Instead, it is reasonable to expect that humanity must adapt and learn to develop new materials and methods to overcome the adversities that we are facing. This master thesis has involved developing novel materials, serving as a small step in the continuous march towards a bright future where this is possible. More specifically, this work sought to combine mesoporous magnesium carbonate with various metal-organic frameworks to utilize the beneficial aspects from each of these constituents. The ambition was that these could be joined to render combined micro-/mesoporous core-shell structures, with high surface areas and many active sites whilst maintaining a good permeability. Numerous different synthesis routes were developed and explored in the pursuit of viable routes to design novel materials with potential future applications within for instance drug delivery, water harvesting from air and gas adsorption. Coreshell structures of the hydrophilic mesoporous magnesium carbonate covered with the hydrophobic zeolitic imidazole framework ZIF-8 was successfully synthesized for the first time, and practical studies demonstrated a dramatically enhanced water stability, which is perceived to have an impact on further research on these materials. ZIF-67 was also combined with mesoporous magnesium carbonate in a similar manner. Further, Mg-MOF-74 was grown directly from mesoporous magnesium carbonate, where the latter acted as a partially self-sacrificing template, with the aim of rendering a porous hierarchical structure with contributions from the micro- and mesoporous ranges. The outcomes of all these syntheses were characterized using several analyzing methods such as scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and nitrogen sorption analysis.
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Method development of an in vitro vertical Franz diffusion cell system to assess permeation of cosmetic active ingredientsMattiasson, Johanna January 2020 (has links)
For evaluation of potential skincare ingredients, an in-house method using Static Franz diffusion cells and dialysis membranes was developed. Benzoic acid was chosen as a model substance along with L-ascorbic acid and α-Tocopherol. The cell conditions were tailored to encourage transmembrane diffusion. Benzoic acid was tested in acetate buffer (pH 4.6), which yielded a maximum flux of 0.91 ± 0.03 mg ∙ cm-2 ∙ h-1 and absorption of 103 ± 4 % out of the applied dose after 8 h. There were strong indications that benzoic acid ionization must be suppressed by lower pH to increase penetration rates. L-ascorbic acid yielded a flux of 0.29 ± 0.01 mg ∙ cm-2 ∙ h-1 in phosphate buffered saline (PBS, pH 7.4) and absorption of 87 ± 7 % of the applied dose after 8 h. Experiments with α-tocopherol showed no penetration in PBS with added bovine serum albumin (BSA), leading to the hypothesis that more hydrophobic membranes and/or receptor medium are needed for the study of lipophilic compounds. In addition, the release of benzoic acid from the amorphous mesoporous magnesium carbonate Upsalite® was investigated. The results showed significant release and penetration of benzoic acid from the solid matrix in both acetate buffer and PBS. The maximum flux was estimated to 6.61 ± 0.96 mg ∙ cm-2 ∙ h-1 in acetate buffer and 99 ± 9 % of the applied dose was absorbed after 3h. Tests of Upsalite with benzoic acid on hydrophobic silicone and Strat-M membranes showed no significant penetration, likely due to insufficient wetting of the sample. Pre-wetting of Strat-M membrane lead to penetration of benzoic acid into the membrane. Flux rates achieved on synthetic membranes are generally much higher compared to skin, which results in this thesis show. In conclusion, data for pure benzoic acid and L-ascorbic acid in the developed method using dialysis membranes showed reasonable agreement with literature. Penetration of benzoic acid is pH-dependent and may be either increased or decreased by choice of skin model or by using Upsalite as vehicle. Choosing a buffer pH below the pKa of the substance may enhance penetration. Introducing L-ascorbic acid in Upsalite could potentially increase the permeation, similar to that of benzoic acid.
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Amorphous Mesoporous Magnesium Carbonate in cosmetics : Absorption and interaction with oils, soft-focus effect and transparencyShebalin, Ivan January 2021 (has links)
Throughout the ages makeup has been used to hide blemishes, blur imperfections and provide an oil free look of the skin. In the past few years, more attention has been given to face powders ingredients as some of them may be associated with health risks as well as impact the environment. Therefore, there is a need for new safe cosmetic ingredients with improved performance. It has previously been shown that Upsalite®, a mesoporous magnesium carbonate with an extraordinary high surface area and narrow pore size distribution, has great potential to replace other powder ingredients used as fillers and absorbers in powder cosmetics. In this work functional and physical attributes of Upsalite in powder cosmetics have been further investigated to generate comparative data for claim support. Oil uptake, speed and interaction were investigated and compared with other powders. In addition, a method to quantify transparency and blurring effect of Upsalite compared to other materials has been developed and applied. It was shown that Upsalite has exceptional absorption capacity of oil and is able to absorb oil much quicker than silica and other cosmetic powders. Preferential interaction with polar compared to non-polar oils was found and the dual interaction of Upsalite with oil and moisture was further substantiated. Transparency studies of Upsalite revealed that Upsalite is more transparent on a glass substrate but was found opaquer on skin than talc and mica. This is explained by that its measured refractive index of 1.62 is slightly higher leading to a somewhat improved coverage. The blurring effect study showed that Upsalite has a blurring index in the range of the best existing cosmetic powders, improving blurring index of mica, talc and BN-12 by up to 60% and can replace silica and microplastics such as Nylon-12. Upsalite was found to visually blur imperfections without looking white.
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Fused deposition modeling of API-loaded mesoporous magnesium carbonateAbdelki, Andreas January 2020 (has links)
In this thesis, the incorporation of drug loaded mesoporous magnesium carbonate as an excipient for the additive manufacturing of oral tablets by fused deposition modeling was investigated. Cinnarizine, a BCS class II drug, was loaded into the pores of the mesoporous material via a soaking method, corresponding to a drug loading of 8.68 wt%. DSC measurements on the loaded material suggested that the drug was partially crystallized after incorporation, meanwhile the XRD diffractogram implied that the drug was in a state lacking long range order. The drug loaded material was combined with two pharmaceutical polymers, Aquasolve LG and Klucel ELF, and extruded into filaments with a single screw extruder. Filaments of Klucel ELF and drug loaded Upsalite (30:70 wt% ratio) were successfully implemented for the printing oral tablets, in contrast to the Aquasolve LG based filaments which were difficult to print due to thickness variations and non-uniform material distributions. The drug content obtained by TGA suggested drug loadings of 7.71 wt% and 2.23 wt% in the drug loaded Upsalite and tablets respectively. Dissolution studies using an USP II apparatus showed a slower API-release from the tablets in comparison to the crystalline drug, most probably due to slow diffusion of drug species through the polymeric matrix. For future studies, pharmaceutical polymers with higher aqueous solubility should be investigated in order to thoroughly examine the potential of utilizing the immediate release property of Upsalite.
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