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1.
Cells ; 10(9)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34571933

RESUMO

Current understanding of functional characteristics and biochemical pathways in taste bud cells have been hindered due the lack of long-term cultured cells. To address this, we developed a holistic approach to fully characterise long term cultured bovine taste bud cells (BTBCs). Initially, cultured BTBCs were characterised using RT-PCR gene expression profiling, immunocytochemistry, flowcytometry and calcium imaging, that confirmed the cells were mature TBCs that express taste receptor genes, taste specific protein markers and capable of responding to taste stimuli, i.e., denatonium (2 mM) and quinine (462.30 µM). Gene expression analysis of forty-two genes implicated in taste transduction pathway (map04742) using custom-made RT-qPCR array revealed high and low expressed genes in BTBCs. Preliminary datamining and bioinformatics demonstrated that the bovine α-gustducin, gustatory G-protein, have higher sequence similarity to the human orthologue compared to rodents. Therefore, results from this work will replace animal experimentation and provide surrogate cell-based throughput system to study human taste transduction.


Assuntos
Biomarcadores/metabolismo , Cálcio/metabolismo , Regulação da Expressão Gênica , Papilas Gustativas/anatomia & histologia , Papilas Gustativas/fisiologia , Sequência de Aminoácidos , Animais , Biomarcadores/análise , Bovinos , Perfilação da Expressão Gênica , Homologia de Sequência
2.
Pharm Dev Technol ; 26(1): 101-109, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33078682

RESUMO

There is a need to accelerate paediatric formulation evaluation and enhance quality of early stage data in drug development to alleviate the information pinch point present between formulation development and clinical evaluation. This present work reports application of DNA microarrays as a high throughput screening tool identifying markers for prediction of bioavailability and formulation driven physiological responses. With a focus on enhancing paediatric medicine provision, an oral liquid spironolactone suspension was formulated addressing a paediatric target product profile. Caco-2 cells cultured on transwell inserts were implemented in transport assays in vitro and DNA microarrays were used to examine gene expression modulation. Wistar rats were used to derive in vivo bioavailability data. In vitro, genomic, and in vivo data sets were concurrently evaluated linking drug transport and the genomic fingerprint generated by spironolactone formulation exposure. Significant changes in gene expression are reported as a result of formulation exposure. These include genes coding for ATP-binding cassette (ABC) transporters, solute carrier (SLC) transporters, cytochrome P450 (CYP) enzymes, and carboxylesterase enzymes. Genomic findings better inform pre-clinical understanding of pharmacokinetic and pharmacodynamic responses to spironolactone and its active metabolites than current in vitro drug transport assays alone.


Assuntos
Composição de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Perfilação da Expressão Gênica/métodos , Espironolactona/administração & dosagem , Espironolactona/farmacocinética , Fatores Etários , Animais , Células CACO-2 , Diuréticos/administração & dosagem , Diuréticos/química , Diuréticos/farmacocinética , Expressão Gênica , Humanos , Masculino , Ratos , Ratos Wistar , Espironolactona/química
3.
J Pharm Sci ; 109(10): 3105-3113, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32710905

RESUMO

Tuberculosis (TB) is believed to affect around 10 million people worldwide. Treatment for TB includes isoniazid and rifampicin, with fixed-dose combination (FDC) recommended for improved patient compliance. Similarly, orally disintegrating tablets (ODTs) are an increasingly popular dosage form that aid compliance since they do not require swallowing. In this study ODTs of isoniazid and rifampicin, either as discrete or FDC doses, were formulated and bioequivalence between single and combination doses compared using in vitro and in silico approaches. Dissolution profiles were compared using FDA advised difference (f1) and similarity (f2) testing in biorelevant media. Rifampicin release from FDCs decreased by approximately 15% in fed-state media (failed f1 and f2), which was attributed to enhanced rifampicin degradation in the presence of isoniazid at lower pH. Apparent permeability (Papp) values derived from Caco-2 transport studies were included alongside dissolution results into a physiologically based pharmacokinetic (PBPK) model, to simulate in vivo bioavailability in healthy subjects. Models showed no difference in bioavailability between formulations or dosing (fasted or fed) state, despite the failures in dissolution-based bioequivalence testing, highlighting shortcomings in f1 and f2 assessment and the strength of PBPK models.


Assuntos
Isoniazida , Tuberculose , Administração Oral , Células CACO-2 , Criança , Estudos Cross-Over , Humanos , Comprimidos , Equivalência Terapêutica , Tuberculose/tratamento farmacológico
4.
Sci Rep ; 10(1): 9021, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488138

RESUMO

Acidic amino acids, aspartic acid (Asp) and glutamic acid (Glu) can enhance the solubility of many poorly soluble drugs including ciprofloxacin (Cip). One of the mechanisms of resistance within a biofilm is retardation of drug diffusion due to poor penetration across the matrix. To overcome this challenge, this work set to investigate novel counter ion approach with acidic amino acids, which we hypothesised will disrupt the biofilm matrix as well as simultaneously improve drug effectiveness. The anti-biofilm activity of D-Asp and D-Glu was studied on Staphylococcus aureus biofilms. Synergistic effect of combining D-amino acids with Cip was also investigated as a strategy to overcome anti-microbial resistance in these biofilms. Interestingly at equimolar combinations, D-Asp and D-Glu were able to significantly disperse (at 20 mM and 40 mM) established biofilms and inhibit (at 10 mM, 20 mM and 40 mM) new biofilm formation in the absence of an antibiotic. Moreover, our study confirmed L-amino acids also exhibit anti-biofilm activity. The synergistic effect of acidic amino acids with Cip was observed at lower concentration ranges (<40 mM amino acids and <90.54 µM, respectively), which resulted in 96.89% (inhibition) and 97.60% (dispersal) reduction in CFU with exposure to 40 mM amino acids. Confocal imaging indicated that the amino acids disrupt the honeycomb-like extracellular DNA (eDNA) meshwork whilst also preventing its formation.


Assuntos
Antibacterianos/farmacologia , Ácido Aspártico/farmacologia , Ciprofloxacina/farmacologia , Ácido Glutâmico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Ácido Aspártico/administração & dosagem , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Ácido Glutâmico/administração & dosagem , Testes de Sensibilidade Microbiana , Staphylococcus aureus/fisiologia
5.
Sci Rep ; 9(1): 12467, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462654

RESUMO

Disintegration time is the key critical quality attribute for a tablet classed as an Orally Disintegrating Tablet (ODT). The currently accepted in vitro testing regimen for ODTs is the standard United States Pharmacopeia (USP) test for disintegration of immediate release tablets, which requires a large volume along with repeated submergence of the dosage form within the disintegration medium. The aim of this study was to develop an in vivo relevant ODT disintegration test that mimicked the environment of the oral cavity, including lower volume of disintegration medium, with relevant temperature and humidity that represent the conditions of the mouth. The results showed that the newly developed Aston test was able to differentiate between different ODTs with small disintegration time windows, as well as between immediate release tablets and ODTs. The Aston test provided higher correlations between ODT properties and disintegration time compared to the USP test method and most significantly, resulted in a linear in vitro/in vivo correlation (IVIVC) (R2 value of 0.98) compared with a "hockey stick" profile of the USP test. This study therefore concluded that the newly developed Aston test is an accurate, repeatable, relevant and robust test method for assessing ODT disintegration time which will provide the pharmaceutical industry and regulatory authorities across the world with a pragmatic ODT testing regime.


Assuntos
Mastigação , Boca , Comprimidos/administração & dosagem , Comprimidos/química , Administração Oral , Adulto , Feminino , Humanos , Masculino , Solubilidade
6.
Pharmaceutics ; 11(6)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185610

RESUMO

Among the many methods available for solubility enhancement, mesoporous carriers are generating significant industrial interest. Owing to the spatial confinement of drug molecules within the mesopore network, low solubility crystalline drugs can be converted into their amorphous counterparts, which exhibit higher solubility. This work aims to understand the impact of drug overloading, i.e., above theoretical monolayer surface coverage, within mesoporous silica on the release behaviour and the thermal properties of loaded drugs. The study also looks at the inclusion of hypromellose acetate succinate (HPMCAS) to improve amorphisation. Various techniques including DSC, TGA, SEM, assay and dissolution were employed to investigate critical formulation factors of drug-loaded mesoporous silica prepared at drug loads of 100-300% of monolayer surface coverage, i.e., monolayer, double layer and triple layer coverage. A significant improvement in the dissolution of both Felodipine and Furosemide was obtained (96.4% and 96.2%, respectively). However, incomplete drug release was also observed at low drug load in both drugs, possibly due to a reversible adsorption to mesoporous silica. The addition of a polymeric precipitation inhibitor HPMCAS to mesoporous silica did not promote amorphisation. In fact, a partial coating of HPMCAS was observed on the exterior surface of mesoporous silica particles, which resulted in slower release for both drugs.

7.
J Pharm Pharmacol ; 71(6): 889-897, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30784086

RESUMO

OBJECTIVE: In this study, we develop and apply a high-throughput screening protocol to investigate the activity of non-ionic surfactants, with a broad range of hydrophilic-lipophilic balance values, against ABCB1-mediated efflux transport and ABCC2-mediated efflux transport. METHODS: Caco-2 cells were grown for 7 days in 96-well plates, then washed and incubated with the test materials for 2 h in the presence of 2.5 µm of either rhodamine 123 (R-123) or 5(6)-Carboxy-2',7' dichlorofluorescein diacetate as probes of ABCB1 and ABCC2, respectively. KEY FINDINGS: Of the surfactants tested, no activity against ABCC2 was detected and all surfactants showing efficacy against ABCB1 had a HLB value of 22 or below. Inhibition of ABCB1 was seen in the order of efficacy to be poloxamer 335 > poloxamer 40 > Crovol A-70 > Myrj S-40 > poloxamer 184 > poloxamer 182 > Etocas 40 > Tween 20 > Etocas 29 > Tween 80 > Acconon C-44 > Span 20. With regard to this inhibition, the distribution of hydrophilic regions is more important than the HLB value. CONCLUSION: This work demonstrates a high-throughput protocol for detecting materials that can modulate ABCB1-mediated efflux. These surfactants could be exploited to improve oral delivery of drugs prone to efflux.


Assuntos
Excipientes/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Tensoativos/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Excipientes/química , Fluoresceínas/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Rodamina 123/metabolismo , Tensoativos/química
8.
PLoS One ; 13(11): e0206651, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383810

RESUMO

Quality by Design (QbD), a current trend employed to develop and optimise various critical pharmaceutical processes, is a systematic approach based on the ethos that quality should be designed into the product itself, not just end tested after manufacture. The present work details a step-wise application of QbD principles to optimise process parameters for production of particles with modified functionalities, using dry particle coating technology. Initial risk assessment identified speed, air pressure, processing time and batch size (independent factors) as having high-to-medium impact on the dry coating process. A design of experiments (DOE) using MODDE software employed a D-optimal design to determine the effect of variations in these factors on identified responses (content uniformity, dissolution rate, particle size and intensity of Fourier transform infrared (FTIR) C = O spectrum). Results showed that batch size had the most significant effect on dissolution rate, particle size and FTIR; with an increase in batch size enhancing dissolution rate, decreasing particle size (depicting absence of coated particles) and increasing the FTIR intensity. While content uniformity was affected by various interaction terms, with speed and batch size having the highest negative effect. Optimal design space for producing functionalised particles with optimal properties required maximum air pressure (40psi), low batch size (6g), speed between 850 to 1500 rpm and processing times between 15 to 60 minutes. The validity and predictive ability of the revised model demonstrated reliability for all experiments. Overall, QbD was demonstrated to provide an expedient and cost effective tool for developing and optimising processes in the pharmaceutical industry.


Assuntos
Preparações de Ação Retardada/síntese química , Desenho de Fármacos , Pressão do Ar , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Celulose/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Ibuprofeno/química , Ibuprofeno/farmacocinética , Modelos Teóricos , Tamanho da Partícula , Medição de Risco , Software , Espectroscopia de Infravermelho com Transformada de Fourier
9.
PLoS One ; 13(2): e0193292, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29489871

RESUMO

The appropriate prescribing of paediatric dosage forms is paramount in providing the desired therapeutic effect alongside successful medication adherence with the paediatric population. Often it is the opinion of the healthcare practitioner that dictates which type of dosage form would be most appropriate for the paediatric patient, with liquids being both the most commonly available and most commonly used. Orally disintegrating tablets (ODTs) are an emerging dosage form which provide many benefits over traditional dosage forms for paediatric patients, such as rapid disintegration within the oral cavity, and the reduction in the risk of choking. However the opinion and professional use of healthcare practitioners regarding ODT's is not known. This study was designed to assess the opinions of several types of healthcare professionals (n = 41) regarding ODTs, using a survey across two hospital sites. Results reaffirmed the popularity of liquids for prescribing in paediatrics, with 58.0% of participants preferring this dosage form. ODTs emerged as the second most popular dosage form (30.0%), with healthcare practitioners indicating an increasing popularity amongst patients in the hospital setting, belief with 63.0% of practitioners agreeing that many liquid formulations could be substituted with a suitable ODT. The desired properties of an ideal ODT were also identified by healthcare practitioners preferring a small, fast disintegrating tablet (90.2% and 95.1% respectively), with the taste, disintegration time and flavour being the three most important attributes identified (29.5%, 28.7% and 21.7% respectively). This study provided a pragmatic approach in assessing healthcare professional's opinions on ODTs, highlighting the ideas and thoughts of practitioners who are on the frontline of paediatric prescribing and treatment and gave an indication to their preference for ODT properties.


Assuntos
Prescrições de Medicamentos , Pessoal de Saúde , Pediatria/métodos , Comprimidos/administração & dosagem , Administração Oral , Obstrução das Vias Respiratórias/prevenção & controle , Feminino , Humanos , Masculino , Guias de Prática Clínica como Assunto
10.
Pharm Dev Technol ; 23(5): 442-453, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28776426

RESUMO

The fast development in materials science has resulted in the emergence of new pharmaceutical materials with superior physical and mechanical properties. Low-substituted hydroxypropyl cellulose is an ether derivative of cellulose and is praised for its multi-functionality as a binder, disintegrant, film coating agent and as a suitable material for medical dressings. Nevertheless, very little is known about the compaction behaviour of this polymer. The aim of the current study was to evaluate the compaction and disintegration behaviour of four grades of L-HPC namely; LH32, LH21, LH11, and LHB1. The macrometric properties of the four powders were studied and the compaction behaviour was evaluated using the out-of-die method. LH11 and LH22 showed poor flow properties as the powders were dominated by fibrous particles with high aspect ratios, which reduced the powder flow. LH32 showed a weak compressibility profile and demonstrated a large elastic region, making it harder for this polymer to deform plastically. These findings are supported by AFM which revealed the high roughness of LH32 powder (100.09 ± 18.84 nm), resulting in small area of contact, but promoting mechanical interlocking. On the contrary, LH21 and LH11 powders had smooth surfaces which enabled larger contact area and higher adhesion forces of 21.01 ± 11.35 nN and 9.50 ± 5.78 nN, respectively. This promoted bond formation during compression as LH21 and LH11 powders had low strength yield.


Assuntos
Celulose/análogos & derivados , Composição de Medicamentos , Celulose/química , Força Compressiva , Composição de Medicamentos/métodos , Elasticidade , Excipientes/química , Fenômenos Mecânicos , Porosidade , Pós , Solubilidade , Comprimidos
11.
Int J Pharm ; 531(1): 80-89, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28818458

RESUMO

The aim of this work was to investigate the efficient targeting and delivery of indometacin (IND), as a model anti-inflammatory drug to the colon for treatment of inflammatory bowel disease. We prepared fast disintegrating tablets (FDT) containing IND encapsulated within poly(glycerol-adipate-co-É·-pentadecalactone), PGA-co-PDL, microparticles and coated with Eudragit L100-55 at different ratios (1:1.5, 1:1, 1:0.5). Microparticles encapsulated with IND were prepared using an o/w single emulsion solvent evaporation technique and coated with Eudragit L-100-55 via spray drying. The produced coated microparticles (PGA-co-PDL-IND/Eudragit) were formulated into optimised FTD using a single station press. The loading, in vitro release, permeability and transport of IND from PGA-co-PDL-IND/Eudragit microparticles was studied in Caco-2 cell lines. IND was efficiently encapsulated (570.15±4.2µg/mg) within the PGA-co-PDL microparticles. In vitro release of PGA-co-PDL-IND/Eudragit microparticles (1:1.5) showed significantly (p<0.05, ANOVA/Tukey) lower release of IND 13.70±1.6 and 56.46±3.8% compared with 1:1 (89.61±2.5, 80.13±2.6%) and 1:0.5 (39.46±0.9 & 43.38±3.12) after 3 and 43h at pH 5.5 and 6.8, respectively. The permeability and transport studies indicated IND released from PGA-co-PDL-IND/Eudragit microparticles had a lower permeability coefficient of 13.95±0.68×10-6cm/s compared to free IND 23.06±3.56×10-6cm/s. These results indicate the possibility of targeting anti-inflammatory drugs to the colon using FDTs containing microparticles coated with Eudragit.


Assuntos
Resinas Acrílicas/química , Sistemas de Liberação de Medicamentos , Indometacina/administração & dosagem , Poliésteres/química , Células CACO-2 , Humanos , Concentração de Íons de Hidrogênio , Ácidos Polimetacrílicos , Comprimidos
12.
PLoS One ; 12(6): e0178772, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28609454

RESUMO

Powder blend homogeneity is a critical attribute in formulation development of low dose and potent active pharmaceutical ingredients (API) yet a complex process with multiple contributing factors. Excipient characteristics play key role in efficient blending process and final product quality. In this work the effect of excipient type and properties, blending technique and processing time on content uniformity was investigated. Powder characteristics for three commonly used excipients (starch, pregelatinised starch and microcrystalline cellulose) were initially explored using laser diffraction particle size analyser, angle of repose for flowability, followed by thorough evaluations of surface topography employing scanning electron microscopy and interferometry. Blend homogeneity was evaluated based on content uniformity analysis of the model API, ergocalciferol, using a validated analytical technique. Flowability of powders were directly related to particle size and shape, while surface topography results revealed the relationship between surface roughness and ability of excipient with high surface roughness to lodge fine API particles within surface groves resulting in superior uniformity of content. Of the two blending techniques, geometric blending confirmed the ability to produce homogeneous blends at low dilution when processed for longer durations, whereas manual ordered blending failed to achieve compendial requirement for content uniformity despite mixing for 32 minutes. Employing the novel dry powder hybrid mixer device, developed at Aston University laboratory, results revealed the superiority of the device and enabled the production of homogenous blend irrespective of excipient type and particle size. Lower dilutions of the API (1% and 0.5% w/w) were examined using non-sieved excipients and the dry powder hybrid mixing device enabled the development of successful blends within compendial requirements and low relative standard deviation.


Assuntos
Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Excipientes/química , Preparações Farmacêuticas/química , Tecnologia Farmacêutica/métodos , Algoritmos , Calibragem , Celulose/química , Ergocalciferóis/química , Gelatina/química , Interferometria , Microscopia Eletrônica de Varredura , Modelos Químicos , Tamanho da Partícula , Pós/química , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Amido/química
13.
Drug Des Devel Ther ; 11: 811-826, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28352156

RESUMO

Cardiovascular disease (CVD) is the leading cause of death among men and women worldwide. In CVD, hypertension and dyslipidemia commonly coexist and are managed through coadministration of amlodipine and atorvastatin, respectively. The case for fixed-dose combination (FDC) oral dosage forms and orally disintegrating tablet (ODT) technology to enhance outcomes and compliance is strong. This work follows the development and characterization of single and FDC ODTs containing amlodipine and atorvastatin, followed by bioequivalence comparison between these single and FDC formulations, using in vitro dissolution and Caco-2 apparent permeability (Papp) and in silico physiologically based pharmacokinetic modeling approaches. ODTs containing amlodipine (5 mg) and atorvastatin (10 mg) either alone or in combination rapidly disintegrated (<30 s) while displaying a radial crushing strength in excess of 100 N and friability ≤1%. In vitro dissolution test was performed in fasted and fed-state simulated intestinal fluid (FeSSIF) and analyzed using high-performance liquid chromatography. Dissolution profiles for single and FDC ODTs were compared using US FDA recommended difference (f1) and similarity (f2) factor testing for bioequivalence. In all cases, there was no difference in active pharmaceutical ingredient dissolution between single or FDC ODTs, with the exception of amlodipine in FeSSIF. Pharmacokinetic clinical trial simulations were conducted using Simcyp (Version 14), incorporating Papp and dissolution data. Simulated clinical trials in healthy volunteers showed no difference in bioavailability based on pharmacokinetic parameters between single and combination doses with either active pharmaceutical ingredient. An increase in Cmax and AUC for atorvastatin in fed subjects was attributed to extended transit along the gut lumen and reduced atorvastatin metabolism due to lower CYP3A4 expression at more distal small intestine absorption sites. The results demonstrated bioequivalence of an FDC ODT for amlodipine and atorvastatin, while highlighting several limitations of f1 and f2 bioequivalence testing and strengths of mechanistic pharmacokinetic modeling for oral drug absorption.


Assuntos
Anlodipino/administração & dosagem , Atorvastatina/administração & dosagem , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Composição de Medicamentos , Modelos Biológicos , Comprimidos/química , Comprimidos/farmacocinética , Administração Oral , Adolescente , Adulto , Anlodipino/farmacocinética , Anlodipino/uso terapêutico , Atorvastatina/farmacocinética , Atorvastatina/uso terapêutico , Disponibilidade Biológica , Células CACO-2 , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
14.
Eur J Hosp Pharm ; 24(6): 332-337, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31156967

RESUMO

OBJECTIVES: The current study aims to evaluate dosage form preferences in children and young adults together with identifying the key pragmatic dosage form characteristics that would enable appropriate formulation of orally disintegrating tablets (ODTs). METHODS: International, multisite, cross-sectional questionnaire of children and young adults aged from 6 to 18 years. Eligibility was based on age, ability to communicate and previous experience in taking medications. The study was carried out at three locations: the UK, Saudi Arabia and Jordan. The questionnaire instrument was designed for participant self-completion under supervision of the study team. RESULTS: 104 questionnaires were completed by the study cohort (n=120, response rate 87%). Results showed that ODTs were the most preferred oral dosage forms (58%) followed by liquids (20%), tablets (12%) and capsules (11%). The preferred colours were pink or white while the preferred size was small (<8 mm) with a round shape. With regard to flavour, strawberry was the most preferred (30.8%), while orange was the least preferred (5.8%). The results also showed that the most important physical characteristics of ODTs were disintegration time followed by taste, size and flavour, respectively. CONCLUSIONS: The results of our study support the WHO's claim for a shift of paradigm from liquid towards ODTs dosage forms for drug administration to young children older than 6 years. Data from this study will also equip formulators to prioritise development of key physical/performance attributes within the delivery system.

15.
J Pharm Pharmacol ; 69(7): 807-822, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27696423

RESUMO

OBJECTIVES: The aim of this study was to investigate the influence of process parameters during dry coating on particle and dosage form properties upon varying the surface adsorbed moisture of microcrystalline cellulose (MCC), a model filler/binder for orally disintegrating tablets (ODTs). METHODS: The moisture content of MCC was optimised using the spray water method and analysed using thermogravimetric analysis. Microproperty/macroproperty assessment was investigated using atomic force microscopy, nano-indentation, scanning electron microscopy, tablet hardness and disintegration testing. KEY FINDINGS: The results showed that MCC demonstrated its best flowability at a moisture content of 11.2% w/w when compared to control, comprising of 3.9% w/w moisture. The use of the composite powder coating process (without air) resulted in up to 80% increase in tablet hardness, when compared to the control. The study also demonstrated that surface adsorbed moisture can be displaced upon addition of excipients during dry processing circumventing the need for particle drying before tabletting. CONCLUSIONS: It was concluded that MCC with a moisture content of 11% w/w provides a good balance between powder flowability and favourable ODT characteristics.


Assuntos
Celulose/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Excipientes/química , Administração Oral , Dureza , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Varredura , Pós , Comprimidos , Termogravimetria/métodos
17.
Sci Rep ; 6: 32498, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27581177

RESUMO

The aim of this work was to investigate alternative safe and effective permeation enhancers for buccal peptide delivery. Basic amino acids improved insulin solubility in water while 200 and 400 µg/mL lysine significantly increased insulin solubility in HBSS. Permeability data showed a significant improvement in insulin permeation especially for 10 µg/mL of lysine (p < 0.05) and 10 µg/mL histidine (p < 0.001), 100 µg/mL of glutamic acid (p < 0.05) and 200 µg/mL of glutamic acid and aspartic acid (p < 0.001) without affecting cell integrity; in contrast to sodium deoxycholate which enhanced insulin permeability but was toxic to the cells. It was hypothesized that both amino acids and insulin were ionised at buccal cavity pH and able to form stable ion pairs which penetrated the cells as one entity; while possibly triggering amino acid nutrient transporters on cell surfaces. Evidence of these transport mechanisms was seen with reduction of insulin transport at suboptimal temperatures as well as with basal-to-apical vectoral transport, and confocal imaging of transcellular insulin transport. These results obtained for insulin are the first indication of a possible amino acid mediated transport of insulin via formation of insulin-amino acid neutral complexes by the ion pairing mechanism.


Assuntos
Ácido Aspártico/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Histidina/farmacologia , Insulina/metabolismo , Lisina/farmacologia , Ácido Aspártico/química , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ácido Desoxicólico/química , Ácido Desoxicólico/toxicidade , Impedância Elétrica , Ácido Glutâmico/química , Histidina/química , Humanos , Concentração de Íons de Hidrogênio , Insulina/química , Cinética , Lisina/química , Mucosa Bucal/citologia , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/metabolismo
18.
PLoS One ; 11(8): e0157267, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27548263

RESUMO

Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XµCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 µm) and large (70 µm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XµCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XµCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats.


Assuntos
Materiais Revestidos Biocompatíveis/química , Composição de Medicamentos/métodos , Projetos de Pesquisa , Comprimidos/química , Composição de Medicamentos/instrumentação , Análise Fatorial , Microscopia Confocal , Nebulizadores e Vaporizadores , Soluções , Molhabilidade , Microtomografia por Raio-X
19.
Drug Discov Today ; 21(4): 550-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26689131

RESUMO

The production of composite particles using dry powder coating is a one-step, environmentally friendly, process for the fabrication of particles with targeted properties and favourable functionalities. Diverse functionalities, such flowability enhancement, content uniformity, and dissolution, can be developed from dry particle coating. In this review, we discuss the particle functionalities that can be tailored and the selection of characterisation techniques relevant to understanding their molecular basis. We address key features in the powder blend sampling process and explore the relevant characterisation techniques, focussing on the functionality delivered by dry coating and on surface profiling that explores the dynamics and surface characteristics of the composite blends.


Assuntos
Composição de Medicamentos , Pós/química , Sistemas de Liberação de Medicamentos , Propriedades de Superfície
20.
Sci Rep ; 5: 16352, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26553127

RESUMO

Mannitol is an essential excipient employed in orally disintegrating tablets due to its high palatability. However its fundamental disadvantage is its fragmentation during direct compression, producing mechanically weak tablets. The primary aim of this study was to assess the fracture behaviour of crystalline mannitol in relation to the energy input during direct compression, utilising ball milling as the method of energy input, whilst assessing tablet characteristics of post-milled powders. Results indicated that crystalline mannitol fractured at the hydrophilic (011) plane, as observed through SEM, alongside a reduction in dispersive surface energy. Disintegration times of post-milled tablets were reduced due to the exposure of the hydrophilic plane, whilst more robust tablets were produced. This was shown through higher tablet hardness and increased plastic deformation profiles of the post-milled powders, as observed with a lower yield pressure through an out-of-die Heckel analysis. Evaluation of crystal state using x-ray diffraction/differential scanning calorimetry showed that mannitol predominantly retained the ß-polymorph; however x-ray diffraction provided a novel method to calculate energy input into the powders during ball milling. It can be concluded that particle size reduction is a pragmatic strategy to overcome the current limitation of mannitol fragmentation and provide improvements in tablet properties.


Assuntos
Manitol/química , Comprimidos/química , Varredura Diferencial de Calorimetria , Cristalização , Composição de Medicamentos , Dureza , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Pós/química , Difração de Raios X
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