Polymer Hydroxypropyl Methylcellulose Research Articles

Effect of microwave radiation on hydroxy propyl methyl cellulose polymer films and HPMC/poly(vinylpyrrolidone) polymer blend films using the wide-angle X-ray technique

The changes in the microstructural parameters of microwave-irradiated hydroxy propyl methyl cellulose (HPMC) and HPMC/PVP (poly(vinylpyrrolidone)) blend films have been studied using the Wide Angle X-Ray Scattering Technique (WAXS) method. The crystal imperfection parameters, such as lattice strain (g%), the average number of unit cells ⟨ N ⟩ counted in a direction perpendicular to Bragg's plane (hkl), spacing of (hkl planes dhkl, crystallite size ⟨ Ds ⟩, distortion width, standard deviation, stacking faults, twin faults, were computed by the whole pattern fitting method. The obtained results were quantified in terms of the radiation dosage given to the samples. X-ray analysis reveals that there is a decrease in the crystallite size with the increase in the radiation dosage. Fourier transform Infra-Red (FTIR) analysis has been also carried out for both the unirradiated and irradiated films to study the effect of microwave radiation on HPMC and HPMC/PVP polymer blend films. The scanning electron microscope study is also carried out to know the surface morphology of these blend films.

Design and in vitro/in vivo evaluation of extended release matrix tablets of nateglinide

AimNateglinide is a quick acting anti-diabetic medication whose potent activity lasts for a short duration. One of the dangerous side effects of nateglinide administration is rapid hypoglycemia, a condition that needs to be monitored carefully to prevent unnecessary fatalities. The aim of the study was to develop a longer lasting and slower releasing formulation of nateglinide that could be administered just once daily. MethodsMatrix tablets of nateglinide were prepared in combination with the polymers hydroxypropylmethylcellulose (HPMC), eudragits, ethyl cellulose and polyethylene oxide and the formulated drug release patterns were evaluated using in vitro and in vivo studies. ConclusionOf the seventeen formulated matrix tablets tested, only one formulation labelled HA-2 that contained 15% HPMC K4M demonstrated release profile we had aimed for. Further, swelling studies and scanning electron microscopic analysis confirmed the drug release mechanism of HA-2. The optimized formulation HA-2 was found to be stable at accelerated storage conditions for 3 months with respect to drug content and physical appearance. Mathematical analysis of the release kinetics of HA-2 indicated a coupling of diffusion and erosion mechanisms. In-vitro release studies and pharmacokinetic in vivo studies of HA-2 in rabbits confirmed the sustained drug release profile we had aimed for.

Characterization of ethylcellulose and hydroxypropyl methylcellulose thin films deposited by matrix-assisted pulsed laser evaporation

In this study is reported the deposition of hydroxypropyl methylcellulose (HPMC) and ethylcellulose (EC) by matrix-assisted pulsed laser evaporation (MAPLE). Both HPMC and EC were deposited on silicon substrates using a Nd:YAG laser (266nm, 5ns laser pulse and 10Hz repetition rate) and then characterized by atomic force microscopy and Fourier transform infrared spectroscopy.It was found that for laser fluences up to 450mJ/cm2 the structure of the deposited HPMC and EC polymer in the thin film resembles to the bulk. Morphological investigations reveal island features on the surface of the EC thin films, and pores onto the HPMC polymer films.The obtained results indicate that MAPLE may be an alternative technique for the fabrication of new systems with desired drug release profile.

Polyampholyte acrylic latexes for tablet coating applications

ABSTRACTPolyampholyte latexes can exist within a certain pH range as low‐viscosity aqueous dispersions, while upon a pH shift to the vicinity of the isoelectric point they undergo ionic coacervation. Three classes of coacervation latexes were synthesized and evaluated for their suitability for use in tablet coating applications. Pharmaceutical tablet coatings are commonly based on hydroxypropyl methyl cellulose, poly(vinyl alcohol), and acrylic polymers. Because of the high viscosity of their aqueous solutions, and to the consequent required low concentrations of the tablet coating polymers in the coating solutions to enable sufficiently low viscosity for effective spray application, the current commercial pharmaceutical tablet coating technology requires the removal of large amounts of water during the manufacturing process. In this work, films prepared from high‐solids, low‐viscosity coacervated acrylic latexes showed good hardness, very low tackiness, an excellent combination of optical properties, and very low water vapor permeability. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40049.

English

This study deals with ophthalmic gel of aceclofenac which is potent non-steroidal antiinflammatory drugs (NSAIDs) and was formulated using polymers hydroxy propyl methyl cellulose (HPMC) (15) cps with methyl cellulose (40) cps and HPMC (15) cps with Carbopol (940). The gels (HP with MC) and (HP with CB), were sterilized and assessed for various parameters like clarity, pH, physical appearance, physical stability, viscosity and uniformity of drug content. The release rate from the aforementioned formulation within a period of 9 h were almost HP with MC batch H4 (84.66%) and for HP with CB batch C1 (80.46%); both ophthalmic gels obeyed zero order kinetics for drug release. The ocular irritation was carried out on male albino rabbits and found no redness, no inflammation and no increases tear. Both formulations in gel were found to be more stable at ambient, refrigerator and incubated temperature. The stability of the gels was evidenced by the degradation rate constant. Ophthalmic gel formulated by HP with MC and HP with CB gels proves to be viable alternative to conventional eye drops as it offers longer precorneal residence time and excellent ocular tolerance. Key words: Carbopol 940 (CB), ophthalmic, gel, hydroxy propyl (HP), methyl cellulose (MC).

Natural gum as mucoadhesive controlled release carriers: evaluation of Cefpodoxime Proxetil by D-Optimal design technique

The present study deals with the development of mucoadhesive controlled release tablets of Cefpodoxime Proxetil to increase the gastric residence time and thus prolong drug release, reduce dosing frequency and improve oral bioavailability. Tablets were prepared using sodium alginate and karaya gum, a natural polymer, with a synthetic polymer hydroxypropylmethylcellulose (K100LV) and Karaya gum with HPMC K100LV in various ratios to optimize the drug release profile using D-Optimal technique. Pre- and post-compression parameters of tablets prepared with various formulations (S1–S9, C1–C9) were evaluated. The FTIR and DSC studies revealed that no physiochemical interaction between excipients and drug. The formulation S7 showed prolonged drug release, and the mechanism of drug release from the optimized formulation was confirmed using the Korsmeyer–Peppas model to be non-Fickian release transport and n value was found 0.605 indicating both diffusion and erosion mechanism from these natural gums. The optimized formulation showed mucoadhesive strength >35 g. An in vivo study was performed on rabbits using an X-ray imaging technique. The radiological evidence suggests that the tablets adheres (more than 10 hours) to a rabbit’s stomach. No significant changes were found in the physical appearance, drug content, mucoadhesive study and in vitro dissolution pattern after storage at 40 °C/75% relative humidity for 3 months.

Improving Oil well Cement Slurry Performance Using Hydroxypropylmethylcellulose Polymer

At present, high temperature oil wells are known as the most problematic for cementing operation due to limitations of polymer. The polymers are significantly used as mutlifunctional additives for improving the properties of cement slurry. At high temperature, viscosity of polymer decreases and unable to obtained desired properties of cement slurry. It becomes then major cause of fluid loss and gas migration during cementing operations. Thus, it necessitates for polymers that can able to enhance viscosity of slurry at elevated temperatures. This paper is aiming to study Hydroxypropylmethylcellulose (HPMC) polymer at high temperature that is able to increase the viscosity at elevated temperature. In response, experiments were conducted to characterize rheological properties of HPMC at different temperatures (30 to 100 °C). Then it was incorporated as multifunctional additive in cement slurry for determining API properties (fluid loss, free water, thickening time and compressive strength). It was observed that HPMC polymer has remarkable rheological properties that can have higher viscosity with respect to high temperatures. The best concentration of HPMC was found from 0.30 to 0.50 gallon per sack. This concentration showed minimal fluid loss, zero free water, high compressive strength and wide range of thickening time in cement slurry. The results signified that HPMC polymer is becoming multifunctional additive in cement slurry to improve the API properties of cement slurry and unlock high temperature oil wells for cementing operations.

Bioadhesive vaginal tablets containing spray dried microspheres loaded with clotrimazole for treatment of vaginal Candidiasis

The aim of the present investigation was to prepare and evaluate novel bioadhesive vaginal tablets containing clotrimazole loaded microspheres in order to provide long-term therapeutic activity at the site of infection. Tablets were prepared by incorporating drug loaded microspheres and using bioadhesive polymers hydroxypropylmethylcellulose, sodium carboxymethylcellulose and Carbopol. Microspheres were prepared by the spray drying technique using Eudragit RS-100 and Eudragit RL-100. Microspheres were characterized by SEM, DSC, FTIR, particle size analysis and evaluated for percentage yield, drug loading, encapsulation efficiency and in vitro drug release. To achieve bioadhesion to the mucosal tissue, optimized microspheres were incorporated into bioadhesive tablets and were evaluated for in vitro drug release, in vitro and in vivo mucoadhesion. FTIR and DSC studies showed that no chemical interaction occurred between the drug and polymers. The sphericity factor indicated that the prepared microspheres were spherical. Formulation Mt6 indicated a controlled in vitro drug release and good bioadhesive strength. The in vivo images confirmed the bioadhesion and retention property of tablets up to 24 h. The results indicated that this drug delivery system can be explored for controlled intravaginal drug release.

Structural, thermal, and electrical studies of sodium iodide (NaI)-doped hydroxypropyl methylcellulose (HPMC) polymer electrolyte films

Solid polymer electrolyte films based on hydroxypropyl methylcellulose (HPMC) complexed with sodium iodide (NaI) were prepared using solution cast method. The dissolution of the salt into the polymer host and the structural properties of pure and complexed HPMC polymer electrolyte films were confirmed by X-ray diffraction (XRD) studies. XRD results revealed that the amorphous domains of HPMC polymer matrix were increased with increase in NaI salt concentration. The degree of crystallinity was found to be high in pure HPMC samples. The thermal properties were studied using differential scanning calorimetry (DSC). DSC results revealed that the presence of NaI in the polymer matrix increases the melting temperature; however, it is observed that fusion heat is high for pure HPMC films. The variation of film morphology was examined by scanning electron microscopy. Fourier transform infrared spectral studies revealed vibrational changes that occurred due to the effect of dopant salt in the polymer. Direct current conductivity was measured in the temperature range of 313–383 K. The magnitude of electrical conductivity was found to increase with the increase in salt and temperature concentration. The data on the activation energy regions (regions I and II) indicated the dominance of ion-type charge transport in these polymer electrolyte films. The composition HPMC:NaI (5:4) is found to exhibit the least crystallinity and the highest conductivity.

Fabrication of Cellulose-based Microparticles at Gas–Liquid Interfaces in a Microchannel

Abstract Cellulose-based microparticles are produced by changing the pH value adjacent to the interfaces between CO2 gas bubbles and an aqueous solution containing the pH-sensitive polymer hydroxypropyl methylcellulose phthalate (HPMCP) in a simple microfluidic system. This method is inexpensive, environmentally friendly, and represents a single-step approach for synthesis of cellulose-based microparticles with a narrow size distribution.

Quick dissolving films of nebivolol hydrochloride: formulation and optimization by a simplex lattice design

Present study aims at formulation and development of quick dissolving film of nebivolol hydrochloride applying simple lattice experimental design using three hetero polymers hydroxypropyl methylcellulose, pullulan and polyvinyl pyrrolidone. Films were prepared using solvent casting technique and optimized formulation was derived by desirability function. Regression equations and contour plots were executed to narrate dependent variables, i.e. percentage drug release in 30 s (Y30), tensile strength, elastic modulus, percentage elongation and load at yield, to independent variables. Results of the experimental design revealed that the independent factors hydroxypropyl methylcellulose and pullulan significantly influenced the mechanical properties and percentage drug release from the film which was ultimately reflect in the formulation of optimized batch. The high % drug release of the film in simulated saliva and simulated gastric fluid indicated that it can be successfully used in drug delivery systems for drugs with high first-pass metabolism.

Formulation and Evaluation of Levetiracetam Extended Release Tablets

Extended release formulation of levetiracetam is approved by the food and drug administration as an add-on to other antiepileptic drugs for adults with partial onset seizures. The main objective of present study was to developed and evaluate matrix tablet of levetiracetam by using various grade of hydroxypropylmethylcellulose (HPMC) polymer. Various trials were taken by using HPMC K4M, K15M, and K100M. Different parameters like Physical properties, FTIR, DSC, in vitro drug release profile and swelling index were determined. In vitro drug release was performed in phosphate buffer pH 6.8. The in vitro release profile was compared with model independent method. Stability studies were performed as per ICH guidelines for 1 month at (40 °C ± 2 °C/75 % ± 5 % RH).Data analysis was performed for determination of drug mechanism and order of drug release. The in vitro drug release profile of optimized formulation was compared with marketed formulation LEVERAXR. The regression value for zero order, first order, Higuchi and Korsmeyer Peppas was found to be 0.9604, 0.9245, 0.9889 and 0.9729, respectively. Similarity factor (f2) and dissimilarity factor (f1) was found to be 88.61 and 1.82, respectively. The FTIR and DSC study shows that there is no chemical interaction between levetiracetam and excipients. From the data analysis, it was concluded that optimized formulation follow Higuchi model having diffusion mechanism. The order of drug release was considered zero order release. Stability study shows that there was no remarkable change in drug release after 1 month. It is concluded that the formulation is stable at accelerated conditions.

Dynamic surface tension studies of mixtures of hydroxypropylmethylcellulose with the double chain cationic surfactants didodecyldimethylammonium bromide and ditetradecyldimethylammonium bromide

Dynamic and equilibrium surface tension experiments were carried out to study the adsorption kinetics of mixtures of the nonionic polymer hydroxypropylmethylcellulose (HPMC) with two double chain cationic surfactants, didodecyldimethylammonium bromide (di-DDAB) and ditetradecyldimethylammonium bromide (di-TDAB). Results are obtained concerning the capacity of the surfactants to lower surface tension, the rate of lowering, the extent of adsorption at the interface, the possibility of changing conformation during and after adsorption, and the interactions between the adsorbed molecules. A time-dependent synergy is observed in most of the mixtures, while in a few cases hindrance effects are observed. The interaction of HPMC with the double chain cationic surfactants resulted in complexes with higher surface activity than the two components alone. Two induction times were observed, the second ones being more significant in the presence of di-TDAB. At concentrations well below the critical micelle concentration (cmc), the critical aggregation concentrations (cac), evidence for clusters is observed.

Psyllium: a promising polymer for sustained release formulations in combination with HPMC polymers

Psyllium has a mucilaginous property that makes it a good candidate to be utilized as an excipient in the preparation of controlled release systems. Various formulations were prepared using theophylline as a model drug and investigated with a view to achieve an ideal slow drug release profile. The addition of hydroxypropyl methylcellulose (HPMC) to psyllium significantly reduced the burst release; however, the percentage of drug release within a 12 h period was too slow and thereby inadequate. This was overcome by the addition of lactose as a hydrophilic filler that enabled a slow release with roughly 80% drug release in 12 h. The inclusion of HPMC within psyllium formulations changed the drug release kinetics from Fickian diffusion to anomalous transport. Granulated formulations demonstrated slower drug release than ungranulated or physical mixture and caused a change in the dissolution kinetics from Fickian diffusion to anomalous transport. Milled granules showed more efficient controlled drug release with no burst release. Milling of the granules also changed the drug release kinetics to anomalous transport. Although psyllium was proved to be a promising polymer to control the drug release, a combination of psyllium-HPMC and formulation processes should be considered in an attempt to achieve a zero-order release.

Organogels, hydrogels and bigels as transdermal delivery systems for diltiazem hydrochloride

In the present study, gel formulations of organogels, hydrogels, and oleo-hydrogel (bigels) were evaluated as transdermal drug delivery systems for diltiazem HCL (DH). Organogels were prepared using soya-bean oil (SO) as a solvent and span 60 (Sp 60), cetyl alcohol (CA) or lecithin-pluronic (PLO) as organogelators without and with different surfactants (2% w/w) namely span 80 (Sp80), tween 20 (T20) and tween 80 (T80). On the other hand, hydrogels were formulated using Hydroxypropyl-methylcellulose (HPMC) polymer and bigels were prepared by mixing organogels with HPMC hydrogels. The prepared gels were analyzed microscopically, thermally by DTA and for pH, and viscosity. The effect of gelator used, surfactant types and pH of the sink on DH release from cellophane membrane was investigated. In addition, the DH permeability across the rabbit skin was evaluated. Finally, the in vivo performance of various gel formulations was assessed based on the hypotensive effects of the drug using hypertensive albino male rat models. The microscopical analysis indicated that the solid fibers formed by gelator particles form the backbone of the organogels while bigels appeared as emulsion like. The addition of surfactants showed an increase in organogel viscosity. The thermal analysis of organogels indicated that the drug present in amorphous not in crystalline form. The release studies indicated that DH release from organogels, hydrogels and bigels could be controlled. The included surfactants decreased the DH release and permeation from organogels compared to those without surfactants using either Sp60 or CA. HPMC hydrogel and Bigels showed higher DH release and permeation rates when compared to organogels. The percent DH released in different pH values was in the following descending order: pH5.5>pH1.2>pH6.8>pH7.4. The in vivo antihypertensive activity of DH using different transdermal gels is arranged as following: hydrogels > PLO organogel > bigel> Sp 60 organogel.

The effect of hydrophilic and hydrophobic polymers on release profiles of diclofenac sodium from matrix tablets

Objective: The current study aimed to develop a matrix type sustained release Diclofenac tablet, using hydrophilic hydroxypropyl methylcellulose (HPMC) and hydrophobic polymer cetyl alcohol (CA). Materials and Methods: Two different polymers, that is, Methocel K15MCR ® and CA were used in various proportions as release controlling factor. Matrix tablets were prepared by wet granulation technique. The physicochemical properties of the granules and tablets were evaluated. In vitro dissolution studies of prepared matrix tablet and patent product Voltaren SR ® tablet (VSR) were performed at pH 7.4 phosphate buffer at 100 rpm, and at 37 ± 0.5°C, and subjected to in vitro bioequivalence study in terms of similarity and difference factors. Stability studies were conducted for 6 months using optimized formulation for extended period of time, both at room temperature and accelerated conditions. The dissolution data were fit to Zero‑order, First‑order, Higuchi, and Korsmeyer‑Peppas’ equations. Results: The formulated tablets showed acceptable weight variation, hardness, drug content uniformity with sustained release matrix characteristics. Hydrophilic Methocel K15 MCR ® matrices‑based tablets showed zero‑order and hydrophobic CA matrices‑based tablets followed first‑order kinetics except for formulation six (F6 showed zero‑order profile). It was found that formulations containing CA showed better dissolution properties with respect to formulations containing Methocel K15 MCR ® in terms of similarity and difference factor. Furthermore, the formulations F4, F5, and F6 exhibited similar drug release profile as compared with VSR tablet, which indicated that these formulations could be bioequivalent with VSR tablet in vitro. Tablets were stable both at room temperature and as well as at accelerated conditions. Conclusion: The present study demonstrated that Diclofenac could be successfully prepared using an appropriate amount of Methocel K15 MCR ® and CA in the form of matrix tablets with similar dissolution profile of patent product Voltaren SR ® . The type of polymers used was found to induce a profound effect on release rate and mechanism.

Effect of inorganic salts on the clouding behavior of hydroxypropyl methyl cellulose in presence of amphiphilic drugs

In this paper we report the effect of two cationic (imipramine hydrochloride (IMP) and promazine hydrochloride (PMZ)) and one anionic (sodium salt of ibuprofen (IBF)) drugs on the clouding behavior of a nonionic polymer hydroxypropyl methyl cellulose (HPMC). Though all the three drugs increase the cloud point (CP) of HPMC, the effect was found to be minimum in the case of IBF. Further, the effect of adding salts (NaF, NaCl, NaBr, NaNO3, Na2SO4, Na3PO4, KCl, KBr, KNO3) in the presence of amphiphilic drugs (IMP and PMZ) on the CP of HPMC was seen. Almost linear decrease in the CP was observed with the [salt] at fixed concentrations of these drugs whereas in the absence of drugs the decrement in the CP was slight. The energetic parameters (ΔGc0, ΔHc0 and TΔSc0) were evaluated and it implies that the disruption of water structure becomes significantly prominent at lower concentrations of the drugs at fixed salt concentrations.

Solid Nanocrystalline Dispersions of Ziprasidone with Enhanced Bioavailability in the Fasted State

Reducing the absorption difference between fed and fasted states is an important goal in the development of pharmaceutical dosage forms. The goal of this work was to develop and characterize a solid nanocrystalline dispersion (SNCD) to improve the oral absorption of ziprasidone in the fasted state, thereby reducing the food effect observed for the commercial formulation. A solution of ziprasidone hydrochloride and the polymer hydroxypropyl methylcellulose acetate succinate (HPMCAS) was spray-dried to form a solid amorphous spray-dried dispersion (SDD), which was then exposed to a controlled temperature and relative humidity (RH) to yield the ziprasidone SNCD. The SNCD was characterized using powder X-ray diffraction, thermal analysis, microscopy, and in vitro dissolution testing. These tools indicate the SNCD consists of a high-energy crystalline form of ziprasidone in domains approximately 100 nm in diameter but with crystal grain sizes on the order of 20 nm. The SNCD was dosed orally in capsules to beagle dogs. Pharmacokinetic studies showed complete fasted-state absorption of ziprasidone, achieving the desired improvement in the fed/fasted ratio.

In vitro release of ketoprofen from hydrophilic matrix tablets containing cellulose polymer mixtures

The effect of cellulose ether polymer mixtures, containing both hydroxypropylcellulose (HPC) and hydroxypropylmethylcellulose (HPMC K15M or K100M), on ketoprofen (KTP) release from matrix tablets was investigated. In order to evaluate the compatibility between the matrix components, Raman spectroscopy, scanning electron microscopy (SEM), and X-ray powder diffraction (XRPD) experiments were performed. The results evidence the absence of significant intermolecular interactions that could eventually lead to an incompatibility between the drug and the different excipients. Formulations containing mixtures of polymers with both low and high viscosity grades were prepared by a direct compression method, by varying the polymer/polymer (w/w) ratio while keeping the drug amount incorporated in the solid dispersion constant (200 mg). The hardness values of different matrices were found within the range 113.8 to 154.9 N. HPLC analysis showed a drug content recovery between 99.3 and 102.1%, indicating that no KTP degradation occurred during the preparation process. All formulations attained a high hydration degree after the first hour, which is essential to allow the gel layer formation prior to tablet dissolution. Independent-model dissolution parameters such as t10% and t50% dissolution times, dissolution efficiency (DE), mean dissolution time (MDT), and area under curve (AUC) were calculated for all formulations. Zero-order, first-order, Higuchi, and Korsmeyer–Peppas kinetic models were employed to interpret the dissolution profiles: a predominantly Fickian diffusion release mechanism was obtained – with Korsmeyer–Peppas exponent values ranging from 0.216 to 0.555. The incorporation of HPC was thus found to play an essential role as a release modifier from HPMC containing tablets.

Response surface optimization of sustained release metformin-hydrochloride matrix tablets: influence of some hydrophillic polymers on the release.

The aim of the present work was designed to develop a model-sustained release matrix tablet formulation for Metformin hydrochloride using wet granulation technique. In the present study the formulation design was employed to statistically optimize different parameters of Metformin hydrochloride tablets at different drug-to-polymer ratios employing polymers Hydroxypropyl methylcellulose of two grades K4M and K100M as two independent variables whereas the dependent variables studied were X60, X120, T50, T90, n, and b values obtained from dissolution kinetics data. The in vitro drug release studies were carried out at simulated intestinal fluids, and the release showed a non-Fickian anomalous transport mechanism. The drug release was found to reveal zero order kinetics. The granules and the tablets were tested for their normal physical, morphological, and analytical parameters and were found to be within the satisfactory levels. There were no significant drug-polymer interactions as revealed by infrared spectra. It has been found out that on an optimum increased Hydroxypropyl methylcellulose K100M concentration and decreased Hydroxypropyl methylcellulose K4M concentration the formulations were elegant in terms of their release profiles and were found to be statistically significant and generable.