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1.
Int J Pharm ; 532(1): 131-138, 2017 Oct 30.
Article in English | MEDLINE | ID: mdl-28859940

ABSTRACT

There has been limited research done on the downstream processing of nanosuspensions into solid oral dosage forms. This paper demonstrates the bead layering process with a layering level at 150% and 240%, as well as the selection and justification of the outer phase excipients for tabletability and disintegrating properties. In a previous study, an itraconazole nanosuspension stabilised by SDS and HPMC E5 was layered onto sugar beads with coating polymer HPMC VLV. In the current study, compression studies with these layered beads utilising the small bead size at 150% or 240% layering levels with outer phase cushioning excipients MCC, copovidone or isomalt were performed. Other excipients such as co-compressed crospovidone-PEG 4000; DCP functioning as a disintegrant; and HPC as a binder was also added. Target output variables were achieved with a balance between an adequate tensile strength and fast dissolution rate with a release of 99.0% (±1.0% SD) within 10min, which is in accordance with the FDA guidance for dissolution testing. The results show that the compaction of nanosuspension-layered beads is a suitable process for processing an itraconazole nanosuspension into a solid dosage form such as a compacted tablet without compromising on drug release.


Subject(s)
Itraconazole/chemistry , Nanoparticles/chemistry , Cellulose/chemistry , Disaccharides/chemistry , Drug Compounding , Drug Liberation , Excipients/chemistry , Hardness , Particle Size , Pyrrolidines/chemistry , Solubility , Sugar Alcohols/chemistry , Sugars/chemistry , Tablets , Tensile Strength , Vinyl Compounds/chemistry
2.
Int J Pharm ; 524(1-2): 443-453, 2017 May 30.
Article in English | MEDLINE | ID: mdl-28400290

ABSTRACT

There is more research required to broaden the knowledge on the downstream processing of nanosuspensions into solid oral dosage forms, especially for coated nanosuspensions onto beads as carriers. This study focuses on bead layering as one approach to solidify nanosuspensions. The aim was to systematically investigate the influence of type of coating polymer (HPMC VLV vs. copovidone), bead material and bead size (sugar vs. MCC, and small vs. large) and coating thickness (50%-150% layering level) on the properties of a dried itraconazole nanosuspension. A stable itraconazole nanosuspension with a mean particle size below 200nm was prepared and a ratio of itraconazole and coating polymer of around 1:1 was identified. XRD and DSC scans revealed that itraconazole remained mostly crystalline after the bead layering process. The fastest dissolution rate was achieved using the small bead size, sugar beads, HPMC VLV as film-forming polymer and lowest layering level, with the best formulation releasing 94.1% (±3.45% SD) within the first 5min. A deterioration of the release profile with increasing layering level was only observed for MCC beads and was more pronounced when copovidone was used as a coating polymer. It was observed that bead layering is a suitable method to process an itraconazole nanosuspension into a solid form without compromising release.


Subject(s)
Chemistry, Pharmaceutical , Itraconazole/analysis , Nanoparticles/chemistry , Drug Compounding , Particle Size , Solubility , Suspensions
3.
J Pharm Sci ; 104(11): 3893-903, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26296236

ABSTRACT

No standard time or pharmacopoeia disintegration test method for orodispersible films (ODFs) exists. The USP disintegration test for tablets and capsules poses significant challenges for end-point determination when used for ODFs. We tested a newly developed disintegration test unit (DTU) against the USP disintegration test. The DTU is an accessory to the USP disintegration apparatus. It holds the ODF in a horizontal position, allowing top-view of the ODF during testing. A Gauge R&R study was conducted to assign relative contributions of the total variability from the operator, sample or the experimental set-up. Precision was compared using commercial ODF products in different media. Agreement between the two measurement methods was analysed. The DTU showed improved repeatability and reproducibility compared to the USP disintegration system with tighter standard deviations regardless of operator or medium. There is good agreement between the two methods, with the USP disintegration test giving generally longer disintegration times possibly due to difficulty in end-point determination. The DTU provided clear end-point determination and is suitable for quality control of ODFs during product developmental stage or manufacturing. This may facilitate the development of a standardized methodology for disintegration time determination of ODFs.


Subject(s)
Technology, Pharmaceutical/instrumentation , Capsules/chemistry , Equipment Design , Reproducibility of Results , Solubility , Tablets/chemistry
4.
J Pharm Sci ; 104(11): 3893-903, 2015 11.
Article in English | MEDLINE | ID: mdl-27524687

ABSTRACT

No standard time or pharmacopoeia disintegration test method for orodispersible films (ODFs) exists. The USP disintegration test for tablets and capsules poses significant challenges for end-point determination when used for ODFs. We tested a newly developed disintegration test unit (DTU) against the USP disintegration test. The DTU is an accessory to the USP disintegration apparatus. It holds the ODF in a horizontal position, allowing top-view of the ODF during testing. A Gauge R&R study was conducted to assign relative contributions of the total variability from the operator, sample or the experimental set-up. Precision was compared using commercial ODF products in different media. Agreement between the two measurement methods was analysed. The DTU showed improved repeatability and reproducibility compared to the USP disintegration system with tighter standard deviations regardless of operator or medium. There is good agreement between the two methods, with the USP disintegration test giving generally longer disintegration times possibly due to difficulty in end-point determination. The DTU provided clear end-point determination and is suitable for quality control of ODFs during product developmental stage or manufacturing. This may facilitate the development of a standardized methodology for disintegration time determination of ODFs. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3893-3903, 2015.


Subject(s)
Capsules/analysis , Endpoint Determination/methods , Tablets/analysis , Technology, Pharmaceutical/instrumentation , Technology, Pharmaceutical/methods , Chemistry, Pharmaceutical , Drug Delivery Systems , Equipment Design , Excipients/analysis , Humans , Reproducibility of Results , Solubility , Water
5.
Int J Pharm ; 455(1-2): 138-47, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-23916824

ABSTRACT

In formulating an orodispersible film (ODF), it is important for polymer choice to strike a balance between mechanical properties and release rates. Studies have been done to study polymer combinations. However, there is a lack of a systematic study to determine key factors affecting these properties. We studied the effect of varying the ratios of a solubilising polymer (Kollidon(®) VA 64 or Soluplus(®)) to a film forming polymer, hydroxypropyl cellulose (HPC), on mechanical properties and release rates of hot-melt extruded ODFs using a 2(3) factorial design. The two drugs evaluated were chlorpheniramine and indomethacin. The main effects impacting mechanical properties were the drug and two-way interaction between drug and solubilising polymer. For dissolution, the main effects were the solubilising polymer; the drug; and the two-way interaction between solubilising polymer and ratio of solubilising to film forming polymer. Both drugs exhibited plasticising effects on the polymer matrix and had higher film ductility and lower film stiffness. Kollidon(®) VA 64-containing films performed better in terms of drug release whereas Soluplus(®)-containing films had better mechanical properties. The dissolution rate can be improved by decreasing film thickness. The findings of our study will be crucial to forming a robust ODF formulation.


Subject(s)
Chemistry, Pharmaceutical , Drug Delivery Systems , Polyethylene Glycols/chemistry , Polyvinyls/chemistry , Povidone/chemistry , Administration, Oral , Cellulose/analogs & derivatives , Cellulose/chemistry , Chlorpheniramine/chemistry , Hot Temperature , Indomethacin/chemistry , Solubility , Technology, Pharmaceutical
6.
BMC Bioinformatics ; 12 Suppl 14: S5, 2011 Dec 14.
Article in English | MEDLINE | ID: mdl-22372988

ABSTRACT

BACKGROUND: It is important to understand the roles of C-type lectins in the immune system due to their ubiquity and diverse range of functions in animal cells. It has been observed that currently confirmed C-type lectins share a highly conserved domain known as the C-type carbohydrate recognition domain (CRD). Using the sequence profile of the CRD, an increasing number of putative C-type lectins have been identified. Hence, it is highly needed to develop a systematic framework that enables us to elucidate their carbohydrate (glycan) recognition function, and discover their physiological and pathological roles. RESULTS: Presented herein is an integrated workflow for characterizing the sequence and structural features of novel C-type lectins. Our workflow utilizes web-based queries and available software suites to annotate features that can be found on the C-type lectin, given its amino acid sequence. At the same time, it incorporates modeling and analysis of glycans - a major class of ligands that interact with C-type lectins. Thereafter, the results are analyzed together with context-specific knowledge to filter off unlikely predictions. This allows researchers to design their subsequent experiments to confirm the functions of the C-type lectins in a systematic manner. CONCLUSIONS: The efficacy and usefulness of our proposed immunoinformatics workflow was demonstrated by applying our integrated workflow to a novel C-type lectin -CLEC17A - and we report some of its possible functions that warrants further validation through wet-lab experiments.


Subject(s)
Lectins, C-Type/chemistry , Software , Algorithms , Animals , Humans , Ligands , Models, Molecular , Polysaccharides/chemistry , Sequence Analysis, Protein , Workflow
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