MyMedR

Displaying all 10 publications

Abstract:

Sort:

Fulltext Continuous Monitoring of the Hydration Behavior of Hydrophilic Matrix Tablets Using Time-Domain NMR

Tsuji T, Ono T, Taguchi H, Leong KH, Hayashi Y, Kumada S, et al.

Chem Pharm Bull (Tokyo), 2023;71(7):576-583.
PMID: 37394606 DOI: 10.1248/cpb.c23-00214

Time-domain NMR (TD-NMR) was used for continuous monitoring of the hydration behavior of hydrophilic matrix tablets. The model matrix tablets comprised high molecular weight polyethylene oxide (PEO), hydroxypropyl methylcellulose (HPMC), and polyethylene glycol (PEG). The model tablets were immersed in water. Their T2 relaxation curves were acquired by TD-NMR with solid-echo sequence. A curve-fitting analysis was conducted on the acquired T2 relaxation curves to identify the NMR signals corresponding to the nongelated core remaining in the samples. The amount of nongelated core was estimated from the NMR signal intensity. The estimated values were consistent with the experiment measurement values. Next, the model tablets immersed in water were monitored continuously using TD-NMR. The difference in hydration behaviors of the HPMC and PEO matrix tablets was then characterized fully. The nongelated core of the HPMC matrix tablets disappeared more slowly than that of the PEO matrix tablets. The behavior of HPMC was significantly affected by the PEG content in the tablets. It is suggested that the TD-NMR method has potential to be utilized to evaluate the gel layer properties, upon replacement of the immersion medium: purified (nondeuterated) water is replaced with heavy (deuterated) water. Finally, drug-containing matrix tablets were tested. Diltiazem hydrochloride (a highly water-soluble drug) was employed for this experiment. Reasonable in vitro drug dissolution profiles, which were in accordance with the results from TD-NMR experiments, were observed. We concluded that TD-NMR is a powerful tool to evaluate the hydration properties of hydrophilic matrix tablets.

Matched MeSH terms: Hypromellose Derivatives/chemistry
Fulltext Mechanism-based selection of stabilization strategy for amorphous formulations: Insights into crystallization pathways

Edueng K, Mahlin D, Larsson P, Bergström CAS

J Control Release, 2017 06 28;256:193-202.
PMID: 28412224 DOI: 10.1016/j.jconrel.2017.04.015

We developed a step-by-step experimental protocol using differential scanning calorimetry (DSC), dynamic vapour sorption (DVS), polarized light microscopy (PLM) and a small-scale dissolution apparatus (μDISS Profiler) to investigate the mechanism (solid-to-solid or solution-mediated) by which crystallization of amorphous drugs occurs upon dissolution. This protocol then guided how to stabilize the amorphous formulation. Indapamide, metolazone, glibenclamide and glipizide were selected as model drugs and HPMC (Pharmacoat 606) and PVP (K30) as stabilizing polymers. Spray-dried amorphous indapamide, metolazone and glibenclamide crystallized via solution-mediated nucleation while glipizide suffered from solid-to-solid crystallization. The addition of 0.001%-0.01% (w/v) HPMC into the dissolution medium successfully prevented the crystallization of supersaturated solutions of indapamide and metolazone whereas it only reduced the crystallization rate for glibenclamide. Amorphous solid dispersion (ASD) formulation of glipizide and PVP K30, at a ratio of 50:50% (w/w) reduced but did not completely eliminate the solid-to-solid crystallization of glipizide even though the overall dissolution rate was enhanced both in the absence and presence of HPMC. Raman spectroscopy indicated the formation of a glipizide polymorph in the dissolution medium with higher solubility than the stable polymorph. As a complementary technique, molecular dynamics (MD) simulations of indapamide and glibenclamide with HPMC was performed. It was revealed that hydrogen bonding patterns of the two drugs with HPMC differed significantly, suggesting that hydrogen bonding may play a role in the greater stabilizing effect on supersaturation of indapamide, compared to glibenclamide.

Matched MeSH terms: Hypromellose Derivatives/chemistry
Formulation strategy of nitrofurantoin: co-crystal or solid dispersion?

Teoh XY, Bt Mahyuddin FN, Ahmad W, Chan SY

Pharm Dev Technol, 2020 Feb;25(2):245-251.
PMID: 31690150 DOI: 10.1080/10837450.2019.1689401

Poor solubility and bioavailability of drugs are often affected by its microscopic structural properties. Nitrofurantoin (NF), a Biopharmaceutics Classification System class II item, has a low water solubility with low plasma concentrations. To improve its therapeutic efficacy, formulation strategy of solid dispersion (SD) and co-crystallization are compared herein. The co-crystal is prepared with citric acid in 1:1 stoichiometric ratio while SD consists of 30% w/w nitrofurantoin and 70% w/w hydroxypropyl methylcellulose (HPMC) as the carrier system. As a control, the physical mixture of NF and HPMC was prepared. All the preparations were characterized with differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), microscopy analysis, solubility, and dissolution studies. The formation of co-crystal, solvent evaporated, and spray-dried SD are confirmed by the ATR-FTIR where peaks shifting of several functional groups indicate the formation of the hydrogen bond. Dissolution studies showed a greater initial dissolution rate in co-crystal than SD despite the possible presence of amorphous content in the SD system. Overall, co-crystal is concluded to be a better approach than SD for an effective dissolution.

Matched MeSH terms: Hypromellose Derivatives/chemistry
In-Vitro and In-Vivo Evaluation of Supersaturable Self-Nanoemulsifying Drug Delivery System (SNEDDS) of Dutasteride

Subramanian P, Rajnikanth PS, Kumar M, Chidambram K

Curr Drug Deliv, 2020;17(1):74-86.
PMID: 31721703 DOI: 10.2174/1567201816666191112111610

OBJECTIVE: A novel, Supersaturable Self-Nanoemulsifying Drug Delivery System (S-SNEDDS) has been prepared to improve the Dutasteride's poor aqueous solubility.
METHODS: By adding Hydroxy Propyl Methyl Cellulose (HPMC) as a precipitation inhibitor to conventional SNEDDS, a supersaturable system was prepared. Firstly, the prepared SNEDDS played an important role in increasing the aqueous solubility and hence oral absorption due to nano-range size. Secondly, the S-SNEDDS found to be advantageous over SNEDDS for having a higher drug load and inhibition of dilution precipitation of Dutasteride. Formulated S-SNEDDS (F1-F9) ranged from 37.42 ± 1.02 to 68.92 ± 0.09 nm with PDI 0.219-0.34 and drug loading of over 95 percent.
RESULTS: The study of in-vitro dissolution revealed higher dissolution for S-SNEDDS compared to SNEDDS and Avodart soft gelatin capsule as a commercial product. In addition, higher absorption was observed for S-SNEDDS showing approximately 1.28 and 1.27 fold AUC (0-24h) and Cmax compared to commercial products. Therefore, S-SNEDDS has proven as a novel drug delivery system with a higher drug load, higher self-emulsification efficiency, higher stability, higher dissolution and pronounced absorption.
CONCLUSION: In conclusion, S-SNEDDS could be a newly emerging approach to enhance aqueous solubility in many folds for drugs belonging to BCS Class II and IV and thus absorption and oral bioavailability.

Matched MeSH terms: Hypromellose Derivatives/chemistry*
Domperidone nanocrystals with boosted oral bioavailability: fabrication, evaluation and molecular insight into the polymer-domperidone nanocrystal interaction

Ndlovu ST, Ullah N, Khan S, Ramharack P, Soliman M, de Matas M, et al.

Drug Deliv Transl Res, 2019 Feb;9(1):284-297.
PMID: 30387048 DOI: 10.1007/s13346-018-00596-w

The aim of this study was to employ experimental and molecular modelling approaches to use molecular level interactions to rationalise the selection of suitable polymers for use in the production of stable domperidone (DOMP) nanocrystals with enhanced bioavailability. A low-energy antisolvent precipitation method was used for the preparation and screening of polymers for stable nanocrystals of DOMP. Ethyl cellulose was found to be very efficient in producing stable DOMP nanocrystals with particle size of 130 ± 3 nm. Moreover, the combination of hydroxypropyl methylcellulose and polyvinyl alcohol was also shown to be better in producing DOMP nanocrystals with smaller particle size (200 ± 3.5 nm). DOMP nanosuspension stored at 2-8 °C and at room temperature (25 °C) exhibited better stability compared to the samples stored at 40 °C. Crystallinity of the unprocessed and processed DOMP was monitored by differential scanning calorimetry and powder X-ray diffraction. DOMP nanocrystals gave enhanced dissolution rate compared to the unprocessed drug substance. DOMP nanocrystals at a dose of 10 mg/kg in rats showed enhanced bioavailability compared to the raw drug substance and marketed formulation. A significant increase in plasma concentration of 2.6 μg/mL with a significant decrease in time (1 h) to reach maximum plasma concentration was observed for DOMP nanocrystals compared to the raw DOMP. Molecular modelling studies provided underpinning knowledge at the molecular level of the DOMP-polymer nanocrystal interactions and substantiated the experimental studies. This included an understanding of the impact of polymers on the size of nanocrystals and their associated stability characteristics.

Matched MeSH terms: Hypromellose Derivatives/chemistry*
Development and physical characterization of polymer-fish oil bigel (hydrogel/oleogel) system as a transdermal drug delivery vehicle

Rehman K, Mohd Amin MC, Zulfakar MH

J Oleo Sci, 2014;63(10):961-70.
PMID: 25252741

Polymer-Fish oil bigel (hydrogel/oleogel colloidal mixture) was developed by using fish oil and natural (sodium alginate) and synthetic (hydroxypropyl methylcellulose) polymer for pharmaceutical purposes. The bigels were closely monitored and thermal, rheological and mechanical properties were compared with the conventional hydrogels for their potential use as an effective transdermal drug delivery vehicle. Stability of the fish oil fatty acids (especially eicosapentanoic acid, EPA and docosahexanoic acid, DHA) was determined by gas chromatography and the drug content (imiquimod) was assessed with liquid chromatography. Furthermore, in vitro permeation study was conducted to determine the capability of the fish oil-bigels as transdermal drug delivery vehicle. The bigels showed pseudoplastic rheological features, with excellent mechanical properties (adhesiveness, peak stress and hardness), which indicated their excellent spreadability for application on the skin. Bigels prepared with mixture of sodium alginate and fish oil (SB1 and SB2), and the bigels prepared with the mixture of hydroxypropyl methylcellulose and fish oil (HB1-HB3) showed high cumulative permeation and drug flux compared to hydrogels. Addition of fish oil proved to be beneficial in increasing the drug permeation and the results were statistically significant (p < 0.05, one-way Anova, SPSS 20.0). Thus, it can be concluded that bigel formulations could be used as an effective topical and transdermal drug delivery vehicle for pharmaceutical purposes.

Matched MeSH terms: Hypromellose Derivatives/chemistry*
Fulltext Formulation and in vitro, in vivo evaluation of effervescent floating sustained-release imatinib mesylate tablet

Kadivar A, Kamalidehghan B, Javar HA, Davoudi ET, Zaharuddin ND, Sabeti B, et al.

PLoS One, 2015;10(6):e0126874.
PMID: 26035710 DOI: 10.1371/journal.pone.0126874

Imatinib mesylate is an antineoplastic agent which has high absorption in the upper part of the gastrointestinal tract (GIT). Conventional imatinib mesylate (Gleevec) tablets produce rapid and relatively high peak blood levels and requires frequent administration to keep the plasma drug level at an effective range. This might cause side effects, reduced effectiveness and poor therapeutic management. Therefore, floating sustained-release Imatinib tablets were developed to allow the tablets to be released in the upper part of the GIT and overcome the inadequacy of conventional tablets.

Matched MeSH terms: Hypromellose Derivatives/chemistry
Smart nanocrystals of artemether: fabrication, characterization, and comparative in vitro and in vivo antimalarial evaluation

Shah SM, Ullah F, Khan S, Shah SM, de Matas M, Hussain Z, et al.

Drug Des Devel Ther, 2016;10:3837-3850.
PMID: 27920499

Artemether (ARTM) is a very effective antimalarial drug with poor solubility and consequently low bioavailability. Smart nanocrystals of ARTM with particle size of 161±1.5 nm and polydispersity index of 0.172±0.01 were produced in <1 hour using a wet milling technology, Dena(®) DM-100. The crystallinity of the processed ARTM was confirmed using differential scanning calorimetry and powder X-ray diffraction. The saturation solubility of the ARTM nanocrystals was substantially increased to 900 µg/mL compared to the raw ARTM in water (145.0±2.3 µg/mL) and stabilizer solution (300.0±2.0 µg/mL). The physical stability studies conducted for 90 days demonstrated that nanocrystals stored at 2°C-8°C and 25°C were very stable compared to the samples stored at 40°C. The nanocrystals were also shown to be stable when processed at acidic pH (2.0). The solubility and dissolution rate of ARTM nanocrystals were significantly increased (P<0.05) compared to those of its bulk powder form. The results of in vitro studies showed significant antimalarial effect (P<0.05) against Plasmodium falciparum and Plasmodium vivax. The IC50 (median lethal oral dose) value of ARTM nanocrystals was 28- and 54-fold lower than the IC50 value of unprocessed drug and 13- and 21-fold lower than the IC50 value of the marketed tablets, respectively. In addition, ARTM nanocrystals at the same dose (2 mg/kg) showed significantly (P<0.05) higher reduction in percent parasitemia (89%) against P. vivax compared to the unprocessed (27%), marketed tablets (45%), and microsuspension (60%). The acute toxicity study demonstrated that the LD50 value of ARTM nanocrystals is between 1,500 mg/kg and 2,000 mg/kg when given orally. This study demonstrated that the wet milling technology (Dena(®) DM-100) can produce smart nanocrystals of ARTM with enhanced antimalarial activities.

Matched MeSH terms: Hypromellose Derivatives/chemistry
Investigation on the effect of polymer and starch on the tablet properties of lyophilized orally disintegrating tablet

Liew KB, Peh KK

Arch Pharm Res, 2021 Aug;44(8):1-10.
PMID: 25579848 DOI: 10.1007/s12272-014-0542-y

Orally disintegrating tablet (ODT) is a user friendly and convenient dosage form. The study aimed to investigate the effect of polymers and wheat starch on the tablet properties of lyophilized ODT, with dapoxetine as model drug. Three polymers (hydroxypropylmethyl cellulose, carbopol 934P and Eudragit® EPO) and wheat starch were used as matrix forming materials in preparation of lyophilized ODT. The polymeric dispersion was casted into a mould and kept in a freezer at -20 °C for 4 h before freeze dried for 12 h. It was found that increasing in HPMC and Carbopol 934P concentrations produced tablets with higher hardness and longer disintegration time. In contrast, Eudragit® EPO was unable to form tablet with sufficient hardness at various concentrations. Moreover, HPMC seems to have a stronger effect on tablet hardness compared to Carbopol 934P at the same concentration level. ODT of less friable was obtained. Wheat starch acted as binder which strengthen the hardness of ODTs and prolonged the disintegration time. ODT comprising of HPMC and wheat starch at ratio of 2:1 was found to be optimum based upon the tablet properties. The optimum formulation was palatable and 80 % of the drug was released within 30 min in the dissolution study.

Matched MeSH terms: Hypromellose Derivatives/chemistry
Fulltext Experimental and molecular modeling approach to optimize suitable polymers for fabrication of stable fluticasone nanoparticles with enhanced dissolution and antimicrobial activity

Ahmed S, Govender T, Khan I, Rehman NU, Ali W, Shah SMH, et al.

Drug Des Devel Ther, 2018;12:255-269.
PMID: 29440875 DOI: 10.2147/DDDT.S148912

Background and aim: The challenges with current antimicrobial drug therapy and resistance remain a significant global health threat. Nanodrug delivery systems are playing a crucial role in overcoming these challenges and open new avenues for effective antimicrobial therapy. While fluticasone (FLU), a poorly water-soluble corticosteroid, has been reported to have potential antimicrobial activity, approaches to optimize its dissolution profile and antimicrobial activity are lacking in the literature. This study aimed to combine an experimental study with molecular modeling to design stable FLU nanopolymeric particles with enhanced dissolution rates and antimicrobial activity.
Methods: Six different polymers were used to prepare FLU nanopolymeric particles: hydroxyl propyl methylcellulose (HPMC), poly (vinylpyrrolidone) (PVP), poly (vinyl alcohol) (PVA), ethyl cellulose (EC), Eudragit (EUD), and Pluronics®. A low-energy method, nanoprecipitation, was used to prepare the polymeric nanoparticles.
Results and conclusion: The combination of HPMC-PVP and EUD-PVP was found most effective to produce stable FLU nanoparticles, with particle sizes of 250 nm ±2.0 and 280 nm ±4.2 and polydispersity indices of 0.15 nm ±0.01 and 0.25 nm ±0.03, respectively. The molecular modeling studies endorsed the same results, showing highest polymer drug binding free energies for HPMC-PVP-FLU (-35.22 kcal/mol ±0.79) and EUD-PVP-FLU (-25.17 kcal/mol ±1.12). In addition, it was observed that Ethocel® favored a wrapping mechanism around the drug molecules rather than a linear conformation that was witnessed for other individual polymers. The stability studies conducted for 90 days demonstrated that HPMC-PVP-FLU nanoparticles stored at 2°C-8°C and 25°C were more stable. Crystallinity of the processed FLU nanoparticles was confirmed using differential scanning calorimetry, powder X-ray diffraction analysis and TEM. The Fourier transform infrared spectroscopy (FTIR) studies showed that there was no chemical interaction between the drug and chosen polymer system. The HPMC-PVP-FLU nanoparticles also showed enhanced dissolution rate (P<0.05) compared to the unprocessed counterpart. The in vitro antibacterial studies showed that HPMC-PVP-FLU nanoparticles displayed superior effect against gram-positive bacteria compared to the unprocessed FLU and positive control.

Matched MeSH terms: Hypromellose Derivatives/chemistry

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links