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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Single channel analysis of thiol binding to a putative site of alcohol action on the glycine receptor

Goldstein, Beth Erlichman 23 October 2009 (has links)
An alcohol and anesthetic binding pocket is hypothesized to exist among transmembrane domains of the α1 glycine receptor (GlyR). Prior work has shown that amino acid residue serine-267 plays a significant role in the enhancing effects of alcohol and anesthetics and is theorized to form part of an alcohol and anesthetic binding cavity among subunit transmembrane domains. Propyl methanethiosulfonate (PMTS), an alcohol-like thiol, was previously shown to bind to a cysteine residue introduced at position 267 (S267C) and this resulted in permanent enhancement of GlyR function. If ethanol is binding to residue 267 in wildtype GlyR to potentiate receptor function then we hypothesized that covalent thiol labeling would produce receptor enhancement by the same mechanisms as ethanol. Using outside-out patch single channel electrophysiology we determined the open and closed dwell-times and burst properties of S267C GlyR in the absence and presence of PMTS. The primary consequence of PMTS binding to S267C GlyR was an increase in the lengths of burst durations, paralleling the main effect of ethanol on wildtype GlyR. Our findings thus provide a new line of evidence suggesting that ethanol is exerting its enhancing effects on the GlyR through its interactions with amino acid residue 267 in the second transmembrane domain. / text
12

Stanovení propylgallátu pomocí uhlíkové pastové elektrody / Determination of propyl gallate on carbon paste electrode

Vysoká, Marie January 2010 (has links)
Propyl gallate (PG) is a significant synthetic antioxidant and preservative. Its determination has been studied at carbon paste electrode (CPE) using differential pulse voltammetry (DPV) and high performance liquid chromatography with electrochemical detection (HPLC-ED) and with UV spectrometric detection (HPLC-UV). Concentration dependences were measured in the media of Britton-Robinson buffer (pH 5) and methanol (20 %, v/v) by DPV and the limit of detection 0,6110-7 moldm-3 was obtained. Using HPLC with a mobile phase consisting of 0,01 moldm-3 phosphate buffer (pH 4) and methanol (50 %, v/v) with potential of working electrode E = +0,8 V and detection wavelength λ = 280 nm, concentration dependences were measured. Limit of detection was determined to 0,39 moldm-3 for HPLC-ED and 4,95 moldm-3 for HPLC-UV. After verification of the extraction procedure PG was determined in vegetable oil. The resulting value of 3,2 mgkg-1 corresponds with permited limits.
13

Mechanistic Profiling of Novel Wafer Technology Developed for Rate-Modulated Oramucosal Drug Delivery

Patel, Rupal 01 November 2006 (has links)
Student Number ; 9901384G - MPharm dissertation - School of Pharmacy and Pharmacology - Faculty of Health Sciences / A lyophilized polymeric wafer system was formulated for the provision of rapid drug release in the oramucosal region. Lyophilization produced a porous sponge-like matrix which allowed simulated saliva to be rapidly imbibed into the hydrophilic structure. This surge of simulated saliva resulted in rapid disintegration of the wafer. Hydroxypropyl cellulose (HPC) was selected as the polymeric platform based on its low gelation potential. Other excipients incorporated into the system were lactose and mannitol as diluents, and glycine as a collapse protectant. A Face Centred Central Composite Design was chosen to establish the significant effects of the independent formulation variables on the physicochemical and physicomechanical properties of the wafer. The formulation variables investigated were, HPC concentration, type of diluent (lactose, mannitol or mixture), concentration of diluent, quantity of glycine and fill volume. An analysis of these variables elucidated the influential factors that may be controlled to form an ‘ideal’ wafer. The concentration of HPC significantly affected the disintegration rate (p=0.003), influx of simulated saliva (p=0.011) and friability (p=0.023). The quantity of diluent present in the system also had significant effect on matrix tolerance (p=0.029) and friability (p=0.032). Statistical optimization was undertaken using stepwise forward and backward regression, and Artificial Neural Networks to predict the ideal combination of the independent variables that would produce an ideal formulation. This wafer was required to produce a matrix disintegration of 3.33%/s, friability of 0.1% loss and maximum matrix resilience. Formulations manufactured with and without model drug, diphenhydramine hydrochloride, reflected no significant differences in their physicomechanical and physicochemical properties. In an attempt to expand the scope of this technology, a preliminary investigation was undertaken to develop a prolonged release wafer system. This was successfully achieved trough the application of crosslinking technology. It was possible to achieve drug released over a period of 6 hours.
14

The Effects of Selective Estrogenic Drugs in the Medial Amygdala on Male Rat Sexual Behavior

Ogaga-Mgbonyebi, Ejiroghene V. 15 December 2010 (has links)
Male rat copulatory behavior is dependent on Testosterone (T) and its metabolites, estradiol (E2) and dihydrotestosterone (DHT). The estrogen receptor (ER) isoforms, ERα and ERβ, exist in the medial Amygdala (MEA) and either receptor might mediate mating behavior. Therefore, the effects of selective estrogenic MEA implants: propyl pyrazole triol (PPT, ERα agonist), diarylpropionitrile (DPN, ERβ agonist), and 1-methyl-4-phenyl pyridinium (MPP, ERα antagonist) were compared to E2 in maintaining sexual behavior. Four groups of male rats were castrated and administered DHT s.c. and bilateral MEA implants containing either cholesterol, E2, PPT or DPN. An additional group of gonadally intact male rats received bilateral MPP-MEA implants. The post-surgical trials showed a significant decrease in the mating behavior of groups that received cholesterol, PPT, or DPN-MEA implants. However, sexual behavior was maintained in male rats that received the E2 or MPP-MEA implants. These results suggest a differential response of the MEA to E2.
15

Implant of a Selective Estrogen Receptor Alpha Agonist to the Male Rat Medial Preoptic Area Maintains Mating Behavior

Habteab, Biniyam Seged 02 May 2007 (has links)
ABSTRACT Evidence from knockout studies in male mice and from experiments in male rats,in which expression of the estrogen receptor alpha (ERα) gene was inhibited in the medial preoptic area (MPO), suggests that ERα is important in the control of male rat mating behavior. Therefore, in this experiment, we tested the hypothesis that activation of ERα in the MPO is sufficient to maintain mating behavior in castrated male rats receiving subcutaneously (s.c.) dihydrotestosterone (DHT), a non-aromatizable androgen. Accordingly, castrated rats treated with DHT s.c. received MPO implants of either: (i) propyl-pyrazole-triol (PPT) (Stauffer, et al 2000; Katzenellenbogen, et al 2000), a selective ERα agonist, (ii) E2 (positive controls) or (iii) cholesterol (negative controls)and sexual behavior was monitored. PPT was as effective as E2 at maintaining mating behavior suggesting that, in the MPO, ERα is sufficient to mediate responses to E2 that underlie male rat mating behavior.
16

Síntese de biomarcadores 3-n-propilergostânicos : comprovação estrutural dos ácidos 3-n-propilergostanóicos em óleos da Bacia de Campos / Synthesis of 3-n-propylergostane biomarkers. Structural proof of 3-npropylergostanoic acids identified in Campos basin oils

Sampaio, Felipe Ribeiro, 1988- 25 August 2018 (has links)
Orientador: Francisco de Assis Machado Reis / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-25T12:23:58Z (GMT). No. of bitstreams: 1 Sampaio_FelipeRibeiro_M.pdf: 2993184 bytes, checksum: 76574cddb68ff72787da04d789b1d24d (MD5) Previous issue date: 2013 / Resumo: Nesse trabalho, foram sintetizados 5 padrões 3n-propil-noresgostanos. Esses compostos são os hidrocarbonetos correspondentes a uma série homóloga de biomarcadores ácidos 3n-propil-ergostanóicos encontrados em óleos de Pampo Sul, Bacia de Campos, os quais estão associados a processos de biodegradação (LIMA, 2010). Considerando-se que a estrutura tridimensional dos biomarcadores é crucial, utilizou-se como material de partida o estigmasterol. A rota sintética consistiu em uma série de reações estereo e regiosseletiva que levaram à formação de compostos com diferentes cadeias laterais ligadas ao C-17. As análises por RMN de 13C e espectrometria de massas confirmaram a estereoquímica 3?-propil, 5?(H), 14?(H), 17?(H) e 20R. A amostra de óleo foi extraída, obtendo-se a fração ácida. Esta foi derivatizada a hidrocarbonetos para que fosse possível a co-injeção com os padrões sintéticos. A co-injeção dos padrões com a amostra de óleo derivatizada confirmou a presença desses compostos, porém para picos menos abundantes. Além disso, foi confirmada a presença de um novo biomarcador / Abstract: In this work, 5 standards 3n(propryl)-norergostanes were synthesized. The compounds are the corresponding hydrocarbons of homologous series of acid biomarkers 3n-propyl-ergostanoics found in Pampo Sul, oils, Campos basin, which are associated with biodegradation processes (LIMA, 2010). Considering that the three-dimensional structure of biomarkers is crucial, stigmasterol was chosen as starting material. The synthetic route consisted in a series of stereo and regioselective reactions leading to the formation of compounds with different side chains attached to C-17. Analysis by 13C NMR and mass spectrometry confirmed the stereochemistry 3?-propil, 5?(H), 14?(H), 17?(H) e 20R. The oil sample was extracted, obtaining the acidic fraction which was submitted to a derivatization process, obtaining the hydrocarbons derivatives that were used in co-injection with the synthetic standards. The co-injection of the standards with the oil sample confirmed the presence of these compounds, however for the less abundant peaks. In addition, a new biomarker was confirmed / Mestrado / Quimica Organica / Mestre em Química
17

Preparation of Styrl Derivatives of 2,3-dimethyl-4,9-dioxo-1(2-propyl)-naphth[2,3-d]

Hayes, David Wayne 06 1900 (has links)
A series of compounds were prepared by condensing 2,3-dimethyl-4,9-dioxo-1-(2-propyl)-naphth[2,3-d] imidazolium iodide with various aromatic aldehydes.
18

Effect and Mechanisms of Action of Intestinal Bacteria and Bioactive Compounds on the Immune System and Metabolism in Obesity Models

Liébana García, Rebeca 01 December 2025 (has links)
Tesis por compendio / [ES] La obesidad representa un importante reto para la salud pública debido a su elevada prevalencia y a las comorbilidades asociadas. Las dietas hipercalóricas activan el sistema inmunitario intestinal y alteran la microbiota intestinal causando daños metabólicos en el organismo. De hecho, la pérdida de homeostasis inmunológica intestinal se considera un evento que precede a la aparición de la inflamación sistémica de bajo grado asociada a la obesidad. Dado que la microbiota intestinal es un factor modificable, su modulación puede convertirse en una oportunidad para reducir el impacto de la obesidad. Por ello la identificación de los factores que participan en la respuesta inflamatoria a las dietas obesogénicas y la búsqueda de alternativas terapéuticas basadas en la microbiota constituyen una vía de investigación prometedora para combatir la obesidad. Esta Tesis Doctoral evalúa el potencial de nuevos probióticos y estrategias dietéticas para combatir la obesidad basadas en sus propiedades inmunomoduladoras. En el Primer Capítulo investigamos el potencial anti-obesogénico del propil propano tiosulfinato (PTS), un compuesto organosulfurado derivado de la especie Allium, en dos dosis diferentes (0,1 o 1 mg/kg/día) utilizando un modelo murino de obesidad inducida por la dieta (DIO). Nuestros hallazgos demostraron los efectos protectores de PTS frente a la obesidad, ya que su administración redujo el peso corporal y mejoró la homeostasis de glucosa. En el tejido adiposo y el hígado, PTS redujo la inflamación y el metabolismo lipídico aberrante causado por la dieta obesogénica. Además, PTS incrementó la actividad termogénica en el tejido adiposo marrón y reforzó la función barrera intestinal. En vista de los modestos cambios en el ecosistema microbiano intestinal, concluimos que estos efectos no eran mediados por la microbiota. En el Segundo Capítulo evaluamos el potencial anti-obesogénico y el mecanismo de acción de una nueva bacteria llamada Phascolarctobacterium faecium DSM 32890. Para ello, realizamos diferentes experimentos in vitro e in vivo usando diferentes cultivos celulares (macrófagos derivados de médula ósea y células linfoides innatas intestinales del grupo 1 (LC1s)) y modelos murinos DIO (ratones C57BL/6J y Rag1-/-). El tratamiento de ratones alimentados con una dieta hipercalórica con P. faecium incrementó la proporción de los macrófagos M2 en el intestino, lo que contrarrestó el aumento de ILC1s y, en última instancia, mitigó la intolerancia a la glucosa y el aumento de peso corporal, independientemente de la viabilidad de la bacteria. Además, P. faecium reforzó la función barrera intestinal y evitó la inflamación sistémica causada por la dieta hipercalórica. Estos beneficios metabólicos se mantuvieron en ausencia de inmunidad adaptativa, pero se perdieron cuando la bacteria se coadministró con un inhibidor (GW2580) de la polarización de macrófagos M2. Por último, realizamos un amplio estudio con datos metagenómicos de 6.361 personas que mostró una relación inversa entre P. faecium y la obesidad, independientemente de la nacionalidad, el sexo o la edad, lo que sugiere la asociación de esta bacteria con la salud metabólica. En el Tercer Capítulo, investigamos la implicación de las ILC1s intestinales en la progresión de la obesidad y las alteraciones metabólicas asociadas. Para ello, evaluamos longitudinalmente la respuesta de las ILC1s y las consecuencias su depleción de ILC1s en un modelo murino DIO. En el intestino, el bloqueo de ILC1s evitó el aumento de macrófagos M1 e ILC2s y promovió la activación de la vía ILC3-IL22, aumentando la producción de mucina, la expresión de péptidos antimicrobianos y el número de células neuroendocrinas. Además, el bloqueo de ILC1s restableció el perfil microbiano y el metaboloma, acercándose al perfil asociado con la salud metabólica. En última instancia, estas mejoras se asociaron con una mayor secreción de hormonas intestinales, y una reducción de la insulinemia y la adiposidad. / [CA] L'obesitat és un repte per a la salut pública degut a la elevada prevalença i les comorbiditats. Les dietes hipercalòriques activen el sistema immunitari intestinal i alteren la microbiota intestinal causant danys metabòlics en l'organisme. De fet, la pèrdua d'homeòstasi immunològica a escala intestinal es considera un esdeveniment primerenc que precedeix l'aparició de la inflamació sistèmica de baix grau associada a l'obesitat. Atés que la microbiota intestinal és un factor modificable, la seua modulació pot convertir-se en una oportunitat per a reduir l'impacte de l'obesitat. Per això, la identificació dels factors que participen en la resposta inflamatòria a les dietes obesogèniques i la recerca d'alternatives terapèutiques basades en la microbiota son una via d'investigació prometedora per a combatre l'obesitat. Aquesta Tesi Doctoral avalua el potencial de nous probiòtics i estratègies dietètiques per a combatre l'obesitat basada en propietats immunomoduladores. En el Primer Capítol investiguem el potencial anti-obesogènic del propil propà tiosulfat (PTS), un compost organosulfurat derivat de l'espècie Allium, en dues dosis diferents (0,1 o 1 mg/kg/dia) utilitzant un model murí d'obesitat induïda per la dieta. Els resultats demostren els efectes protectors de PTS enfront a l'obesitat, ja que la seua administració va reduir el pes corporal i va millorar l'homeòstasi de glucosa. En el teixit adipós i el fetge, PTS va prevenir l'augment de la resposta inflamatòria i les alteracions del metabolisme lipídic causades per la dieta hipercalòrica. A més, PTS va incrementar l'activitat termogènica en el teixit adipós marró i millorà la funció barrera intestinal alterats per la dieta. Observàrem canvis modestos en la microbiota intestinal, concloent que els efectes no estan mediats de manera significativa per la microbiota. En el Segon Capítol avaluem el potencial anti-obesogènic i el mecanisme d'acció d'un nou bacteri Phascolarctobacterium faecium DSM 32890. Hem realitzat experiments in vitro i in vivo utilitzant diferents cultius cel·lulars (macròfags derivats de medul·la òssia i de cèl·lules limfoides innates intestinals del grup 1 (LC1s) i models murins d'obesitat induïda per la dieta (ratolins C57BL/6J, i Rag1-/- ). El tractament de ratolins alimentats amb una dieta hipercalòrica amb P. faecium incrementà la proporció dels macròfags M2 a l'intestí, contrarestant l'augment d'ILC1s i en última instància, mitigà la intolerància a la glucosa i l'augment del pes corporal, independentment de la viabilitat del bacteri. A més, P. faecium reforçà la funció bacterial intestinal i evità la inflamació sistèmica causada per la dieta hipercalòrica. Aquests beneficis metabòlics es mantenien en absència d'immunitat adaptativa, però es perderen quan el bacteri es coadministrà amb un inhibidor (GW2580) de la polarització de macròfags M2. Finalment, realitzàrem un ampli estudi amb dades metagenòmiques de 6.361 persones que mostrà una relació inversa entre P. faecium i l'obesitat, independentment de la nacionalitat, el sexe o l'edat, suggerint l'associació d'aquest bacteri amb la salut metabòlica. En el Tercer Capítol, investiguem la implicació de les ILC1s residents en l'intestí en la progressió de l'obesitat i les alteracions metabòliques associades. Evaluàrem longitudinalment la resposta de les ILC1s i les conseqüències de la depleció de ILC1s en un model murí d'obesitat. A l'intestí, el bloqueig de ILC1s va evitar l'augment de macròfags M1 i ILC2s, i va promoure l'activació de la via ILC3-IL22, augmentant la producció de mucina, l'expressió de pèptids antimicrobians i el nombre de cèl·lules neuroendocrines. El bloqueig de ILC1s va restablir la microbiota i el seu metaboloma, similar a l'estat saludable. Aquestes millores es van associar amb una major secreció d'hormones intestinals, i una reducció de la insulinèmia i l'adipositat. / [EN] Obesity is a major public health challenge due to its high prevalence, and association with metabolic comorbidities. Hypercaloric diets are known to overactivate the intestinal immune system and disrupt the microbiome, ultimately causing detrimental metabolic effects. The loss of intestinal immune homeostasis is considered an early step preceding the development of systemic low-grade inflammation associated with obesity and metabolic complications. In this regard, extensive evidence supports that the gut microbiome may be modified favorable and, thus, help to ameliorate these conditions. Hence, identifying factors triggering the low-grade inflammation and microbiome-base solutions to reduce the obesity burden represent promising avenues of research. This Doctoral Thesis aims to advance the knowledge and provide novel probiotics and dietary strategies to combat the burden of obesity based on their immunomodulatory properties to shape the metabolic response to the diet. In the First Chapter, we have investigated the anti-obesogenic potential of propyl propane thiosulfinate (PTS), an organo-sulfur compound derived from Allium species, at two different doses (0.1 or 1 mg/kg/day) using a murine model of diet-induced obesity (DIO). Our preclinical findings showed the protective effects of PTS against obesity, reducing body weight gain and maintaining glucose homeostasis, thus suggesting its potential to ameliorate the impact of the HFHSD. In the adipose tissue and the liver, PTS reduced inflammation and the aberrant lipid metabolism caused by the obesogenic diet. Additionally, PTS promoted thermogenic activity in the brown adipose tissue and enhance intestinal gut barrier defense. In view of the modest changes in the microbial ecosystem, we concluded that the effects of PTS were not mediated by the gut microbiota. In the Second Chapter, we have evaluated the anti-obesogenic potential and the mechanism of action of the new intestinal strain, Phascolarctobacterium faecium DSM 32890, isolated in our laboratory from a healthy volunteer. To that aim, we have performed different in vitro and in vivo experiments, including the use of different types of cell cultures (bone marrow-derived macrophages and group 1 of innate lymphoid cells (ILC1s)) and DIO murine models (wild-type C57BL/6J and Rag1-/- mice). Treatment of HFHSD-fed mice with P. faecium, regardless of its viability, shifted the macrophage phenotype towards an M2-type, which counteracted the obesity-induced increase in gut-resident ILC1s and ultimately mitigated glucose intolerance and body weight gain. Moreover, P. faecium treatment prevented systemic inflammation, boosted secretory immunoglobulin A production and induced antimicrobial peptide and interleukin 22 expression. These metabolic benefits were maintained in the absence of an adaptive immune system but were lost when the bacterium was co-administered with an inhibitor (GW2580) of M2 macrophage polarization. We confirmed that P. faecium was more prevalent in the gut metagenomes of non-obese adults regardless of nationality, sex or age, suggesting that it might contribute to safeguard metabolic health in humans. In the Third Chapter, we have investigated the involvement of gut-resident ILC1s in obesity progression and metabolic disruption. To address this goal, we evaluated longitudinally, in a DIO murine model, the ILC1s response to an obesogenic diet and the consequences of the ILC1s depletion. In the intestine, ILC1s depletion blunted the increases in M1 macrophages and ILC2s. Additionally, ILC1s depletion promoted the ILC3-IL22 pathway, increasing mucin production, the expression of antimicrobial gut peptides, and the number of neuroendocrine cells. Moreover, ILC1s depletion restored microbial and metabolomic profiles, resembling those associated with a healthy symbiotic state. The improvements in gut homeostasis were linked to a higher gut hormone secretion, and reduced insulinemia and adiposity. / Rebeca Liébana García has been beneficiary of an FPU contract (FPU 18/02026) and a mobility grant (EST22/00430) from Spanish Ministry of Universities. The experimental work conduced in this Doctoral Thesis has been funded by the Spanish Ministry of Science and Innovation (MICINN AGL2017-88801-P, PID2020-119536RB-I00), the Centre for the Development of Industrial Technology (CDTI, Ref 20170847), and the EU H2020 Marie Sklodowska Curie Actions (MSCA-IF “MicroILCs, GA: 8905454). / Liébana García, R. (2023). Effect and Mechanisms of Action of Intestinal Bacteria and Bioactive Compounds on the Immune System and Metabolism in Obesity Models [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/201910 / Compendio
19

Funkce proteinu LmbW v biosyntéze antibiotika linkomycinu / Function of LmbW protein in biosynthesis of antibiotic lincomycin

Steiningerová, Lucie January 2015 (has links)
4-Alkyl-L-proline derivatives (APD) are specialized precursors involved in the biosynthesis of at least three groups of different natural compounds: some pyrrolo-1,4-benzodiazepines with antitumor activity, bacterial hormone hormaomycin and clinically used lincosamide antibiotic lincomycin. These compounds share a biosynthetic pathway encoded by 5 or 6 homologous genes present in the biosynthetic gene clusters of the producing organisms. Similarities in biosynthesis and differences between APD structures of these compounds could be used to prepare a hybrid producing strain of biologically more effective lincomycin derivative. Unusual amino acid 4-propyl-L-proline (PPL) is the APD precursor of lincomycin. The originally proposed scheme of the PPL pathway does not comply with our current knowledge. Therefore, it was necessary to revise this scheme according to new results. The first two steps of the PPL pathway are functionally proved. Probing the next step was the main aim of this work. The protein LmbW was overproduced and its methyltransferase activity was confirmed in vitro. LmbW is able to directly methylate intermediate of second step of the pathway while the originally scheme proposed methylation at a later stage of biosynthesis. LmbW is also able to attach a longer alkyl chain to its substrate. This...
20

Suitability of cellulose ester derivatives in hot melt extrusion : thermal, rheological and thermodynamic approaches used in the characterization of cellulose ester derivatives for their suitability in pharmaceutical hot melt extrusion

Karandikar, Hrushikesh M. January 2015 (has links)
Applications of Hot Melt Extrusion (HME) in pharmaceuticals have become increasingly popular over the years but nonetheless a few obstacles still remain before wide scale implementation. In many instances these improvements are related to both processing and product performance. It is observed that HME process optimisation is majorly focused on the active pharmaceutical ingredient's (API) properties. Characterising polymeric properties for their suitability in HME should be equally studied since the impact of excipients on both product and process performance is just as vital. In this work, two well-established cellulose ester derivatives: Hydroxy Propyl Methyl Cellulose Acetate Succinate (HPMCAS) and Hydroxy Propyl Methyl Cellulose Phthalate (HPMCP) are studied for their HME suitability. Their thermal, thermodynamic, rheological, thermo-chemical and degradation kinetic properties were evaluated with model plasticisers and APIs. It was found the thermal properties of HPMCP are severely compromised whereas HPMCAS is more stable in the processing zone of 150 to 200 °C. Thermodynamic properties revealed that both polymers share an important solubility parameter range (20-30 MPa P1/2P) where the majority of plasticisers and BCS class II APIs lie. Thus, greater miscibility/solubility can be expected. Further, the processability of these two polymers investigated by rheometric measurements showed HPMCAS possesses better flow properties than HPMCP because HPMCP forms a weak network of chain interactions at a molecular level. However, adding plasticisers such as PEG and TEC the flow properties of HPMCP can be tailored. The study also showed that plasticisers have a major influence on thermo-chemical and kinetic properties of polymers. For instance, PEG reduced polymer degradation with reversal in kinetic parameters whereas blends of CA produced detrimental effects and increased polymer degradation with reduction in onset degradation temperatures. Further, both polymers are observed to be chemically reactive with the APIs containing free -OH, -SOR2RN- and -NH2 groups. Finally, these properties prove that suitability of HPMCP is highly debated for HME and demands great care in use while that of HPMCAS is relatively better than HPMCP in many instances.

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