Browsing by study line "Farmaceutisk teknologi"
Now showing items 1-6 of 6
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(2021)Lääketieteen kehittyessä yksilöllisen lääkehoidon tarpeeseen on kiinnitetty enemmän huomiota kuin aikaisemmin ja etenkin lapsille lääkkeiden tarkka annostelu on erityisen tärkeää. Kaupallisilla valmisteilla tarpeeksi pienet annokset eivät usein ole mahdollisia eikä tablettien puolittaminen takaa tarkkaa lääkkeiden annostelua. 3D-tulostamista on ajateltu mahdollisena vaihtoehtona ex tempore -lääkkeiden tuotantoon ja sen mahdollisuuksia on tutkittu laajalti viime vuosien aikana. Tämän tutkimuksen tavoitteena on selvittää, miten ekstruusiomenetelmällä tulostetut varfariinikalvot vertautuvat sairaala-apteekin käyttämiin varfariiniannosjauheisiin, sekä olisiko kyseistä menetelmää mahdollista hyödyntää sairaala-apteekeissa. Tutkimuksessa valmistettiin puolikiinteän aineen ekstruusiolla 0,1 mg:n, 0,5 mg:n ja 2 mg:n varfariinikalvoja, jotka kuivattiin 85 ℃:ssa valmistusprosessin nopeuttamiseksi. Kalvoja verrattiin saman vahvuisiin varfariinia sisältäviin sairaala-apteekin valmistamiin annosjauheisiin. Kalvoissa käytettiin hydroksipropyylimetyyliselluloosaa kalvonmuodostaja-aineena ja glyserolia tuomaan plastisuutta. Annosjauheet koostuivat kaupallisesta 5 mg:n Marevan-valmisteesta ja täyteaineena käytetystä laktoosista. Molemmista lääkevalmisteista mitattiin liukenemisnopeus ja annosyksiköiden yhdenmukaisuus. Molempien valmisteiden toimivuus nenä-mahaletkussa tutkittiin myös, sillä kalvojen on tärkeää soveltua erilaisille potilasryhmille. Kalvot olivat kovia, mikä aiheutti niiden hitaan liukenemisen. Puolikiinteän aineen valmistus ja tulostuksen toteuttaminen tavoitteiden mukaisesti osoittautui oletettua vaikeammaksi. Kalvoissa mitattiin annosjauheita tasaisempi lääkeainepitoisuus. Molempien lääkevalmisteiden kohdalla huomattiin, että kaikki varfariini ei pääse nenä-mahaletkujen läpi. Tärkein huomio oli, että hyvin yksinkertaisella formulaatiolla on mahdollista tuottaa lupaavia lääkevalmisteita. Tämä tutkimus esittelee syitä, joiden vuoksi 3D-tulostusta on hyvä tutkia mahdollisena ex tempore -valmistuksen menetelmänä.
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(2022)Indomethacin is in a BCS-classification class two drug, meaning it has poor solubility but good permeability. Because of this solubility is a limiting factor for it reaching bloodcirculation. Amorphous form has better solubility than crystalline form. Most common problems with amorphous form are poor stability and process technical problems. In this study Indomethacin was combined with two different kind of polymers that were prepared by hot-melt extrusion. By hot-melt extrusion we can get more stable product than pure amorphous drug. These polymers were polyvinylpyrrolidone (PVPK179 and polyvinylpyrrolidonevinylacetate (PVPVA). They were prepared with Indomethacin 1:1 mass ratio. The aim was to study these extrudates and their stability, cumulative release and especially permeability. By using differential scanning calorimetry, X-ray diffraction and polarized light microscopy it was possible to analyze whether the drug was amorphous or crystalline. In the study it was found that by using hot-melt extrusion it was possible to make amorphous combinations of Indomethacin and polymers. Their permeability was between crystalline and amorphous form. PVPK17-Indomethacin combination had better permeability than PVPVA-Indomethacin combination. On the other hand PVPVA-Indomethacin had better cumulative release than PVPK17-Indomethacin combination
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(2022)Drug-induced liver injury (DILI) is a relatively rare hepatic condition that can be classified as predictable and unpredictable. However, DILI is a primary reason for drug withdrawals, post-marketing warnings, and restrictions of use. DILI is a problem for the drug users but also for the pharmaceutical industry and regulatory bodies. From the perspective of patients' and clinicians', DILI is the major cause of acute liver injury. At present, a major problem predicting DILI in drug discovery is a poor understanding of its mechanisms as well as the complexity of DILI pathogenicity. The main mechanism behind DILI are alterations in bile acid homeostasis, oxidative stress, and mitochondrial dysfunction. More than 50 % of drugs causing DILI are causing mitochondrial impairment. If the normal function of mitochondria is disturbed, the energy production of the cell decreases, and cell function decline leading eventually to the cell death. In this study prediction of mitochondrial toxicity was studied using cryopreserved primary hepatocytes of humans and rats. The aim of the study was to clarify if there are interspecies differences in the prediction of toxicity but also investigate possible differences in the mechanisms behind hepatotoxicity by using three well-known compounds toxic to mitochondria. To determine these differences, total cellular ATP was measured after 2- and 24- hour exposure time to gain information on overall viability and possible adaptive responses. Mitochondrial energy pathways were studied as a real-time monitoring acute exposure of test compounds. Morphology, location, and possible adaptive response of mitochondria were studied using a fluorescent probe and antibody staining combined with high content imaging (HCI). Overall, primary rat hepatocytes were more sensitive to the test compounds than human hepatocytes. Also, there were differences between human hepatocyte batches that may reflect the metabolic differences between hepatocyte donors. Immunolabeling did not bring any additional values compared to the fluorescent probe staining in the study of morphology of mitochondria. Additionally, it was noticed that treatment with paraformaldehyde significantly changed the hepatocyte mitochondria morphology. Overall, more effort is needed to develop image analysis of mitochondria morphology. Finally, studying mitochondrial morphology has proven to be difficult, and this study did not unfortunately reveal any information about the adaptive responses of mitochondria for drug-induced liver injury.
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(2022)Lääkeaineiden niukkaliukoisuus on yhä enemmän esiintyvä ongelma lääketeollisuudessa. Erityisesti BCS ryhmän II lääkeaineet ovat potentiaalisia liukoisuusominaisuuksia parantaville menetelmille. Tässä työssä näistä menetelmistä keskitytään nanokiteen, ko-kiteen ja ko-amorfisen systeemin muodostukseen ja lääkeaineena käytetään inodmetasiinia (BCS ryhmä II). Kyseisillä menetelmillä on onnistuttu parantamaan indometasiinin liukoisuusominaisuuksia, mutta vertailevia tutkimuksia ei ole aiemmin tehty. Nanokide valmistettiin märkäjauhamalla käyttäen poloksameeri 188 -stabilisaattoria. Ko-kiteen valmistuksessa käytettiin liuottimen haihdutus -menetelmää ja ko-muodostajana sakariinia. Ko-amorfisten systeemien ko-muodostajina käytettiin l-tryptofaania ja sitruunahappoa ja valmistus toteutettiin kuulamyllyllä jauhamalla. Karakterisointimenetelmillä (DLS, DSC ja XRPD) oli mahdollista todentaa nanokiteillä ja ko-kiteillä halutut ominaisuudet (partikkelikoko ja kiderakenne). Ko-amorfinen systeemi ei työssä käytetyllä menetelmällä saavuttanut amorfista rakennetta kummallakaan ko-muodostajalla. Vaikka jauhe osittain muuttui kellertäväksi (viitaten amorfiseen indometasiiniin) olivat XRPD:n ja DSC:n tulokset kiteiselle aineelle tyypillisiä. Nanokiteellä ja ko-kiteellä saavutettiin puhdasta indometasiinia parempi ominaisliukenemisnopeus sekä liukenemisnopeus jauheesta lapamenetelmällä. Systeemien välisessä vertailussa huomattiin, että nanokiteellä oli parempi liukenemisnopeus molemmissa kokeissa. Ero on selkeämmin nähtävissä lapamenetelmässä: pieni partikkelikoko mahdollistaa suuren suhteellisen pinta-alan liukenemista varten. Systeemien fysikaalista stabiilisuutta tutkittiin yhdeksän kuukauden ajan suljetussa muoviastiassa laboratorio-olosuhteissa (huoneenlämpö ja normaali ilmankosteus). Kummassakaan systeemissä ei ollut nähtävissä kiderakenteen muutoksia. Nanokiteillä oli havaittavissa lievää partikkelikoon kasvua, mikä on selitettävissä ennen koetta tehdyn sekoituksen tehottomuudella
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(2023)Solids most commonly come in two broad forms: crystalline or amorphous. Crystalline solids have a regular, organized long-range structure of atoms and crystals, and are characterized by having a distinct shape, specific volume, and melting point. They can also have multiple polymorphs. On the other hand, amorphous solids do not usually have a regular long-range atomic and crystal structure and their molecules are more easily separated, which makes them more soluble in their surroundings compared to crystalline solids. However, despite this, short-range order can also occur. To improve the solubility of crystalline solids, co-amorphous systems can be created by mixing together two or more chemically different compounds in a way that they don't form a regular crystalline structure, but rather an irregular, amorphous one. Co-amorphous systems can be analyzed qualitatively or quantitatively. Qualitative analysis is often the main focus when studying amorphous matter, as it can be difficult to accurately quantify these materials using techniques based on crystal structures. Additionally, many amorphous systems are made up of complex mixtures of polymers with different chemical and physical properties. This study aimed to determine the most effective method for obtaining quantitative information about the co-amorphization of indomethacin and tryptophan. Three analytical techniques were used for this purpose: differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and Raman spectroscopy. The co-amorphous system was created by mixing together α-indomethacin and tryptophan, γ-indomethacin and tryptophan, and amorphous indomethacin and tryptophan. This study showed that DSC, XRPD, and Raman spectroscopy are effective in providing quantitative information about crystallinity and crystal size. These techniques were able to accurately detect and characterize discrete residual crystals, and were able to measure and quantify the amount of these substances. Even though these methods may not be able to detect nanoscale structures with precision, they still provided valuable information about the crystalline and amorphous nature of the samples studied. Additionally, the fact that similar quantitative results were obtained using different analysis methods further supports the reliability of these techniques. Of all the techniques discussed, Raman spectroscopy was able to identify even small residual crystals, resulting in the highest calculated crystallinity percentage.
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(2023)Poorly water soluble active pharmaceutical ingredients cause problems for the drug development. Solid state modification offers one approach to overcome the issue. In this study, co-amorphous systems and co-crystals were prepared with indomethacin at molar ratio of 1:1 using nicotinamide as a co-former. Co-amorphous systems were prepared by two different preparation methods: melting the physical mixture and then quench cooling it with liquid nitrogen and dry milling with a ball mill. Co-crystals were prepared by liquid-assisted ball milling. After that, the properties, dissolution, and physical stability of the formed formulations were investigated and compared. The characterisation methods were differential scanning calorimetry, X-ray powder diffraction, Fourier-transform infrared spectroscopy, polarised light microscope and scanning electron microscope. In addition, the solubility and physical stability of the formulations were investigated. Co-amorphous systems were successfully prepared by quench cooling the melt and co-crystals by liquid-assisted ball milling. Dry milling did not induce the formation of co-amorphous systems. In the intrinsic dissolution test, both the co-amorphous system and co-crystal enhanced the dissolution of crystalline indomethacin. When examining the dissolution rate with the paddle apparatus, it was observed that the co-crystal had the highest dissolution rate among both powder and tablet samples. The co-amorphous powder sample floated on the surface of dissolution medium which impeded the dissolution of indomethacin. However, co-amorphous tablet sample showed a higher dissolution rate than crystalline indomethacin. Stability testing (25 °C, 18 %RH) showed that the co-amorphous system recrystallised into a co-crystal after two weeks of storage, while the co-crystal was found to stay stable the whole study period.
Now showing items 1-6 of 6