Kollicoat IR Research Articles

Fabrication of Hierarchical Polymeric Thin Films by Spin Coating Toward Production of Amorphous Solid Dispersion for Buccal Drug Delivery System: Preparation, Characterization, and In Vitro Release Investigations

The landscape of thin films is continuously evolving as an attractive self-administration mean to drive patient compliance. This work reports incorporation of drugs into various polymeric compositions using spin coating technology to screen amorphous solid dispersion film formation for buccal applications. Polarized light microscopy and differential scanning calorimetry were used for characterization. Physical stability was assessed after films storage at 0% RH/25°C for 6 months. Chlorpheniramine maleate, theophylline, and famotidine were used as model drugs and mixed with Opadry amb II® or Kollicoat IR®. Acryl-EZE II® or Zein was also used as surface (design I) or surface and base polymers (design II). Of all the drug-Opadry combinations, only chlorpheniramine was amorphously dispersed up to 25% (w/w). In contrast, Kollicoat IR® resulted in amorphous dispersions of all the tested drugs, suggesting that it has a better solubilization capacity. Drugs prepared in design II achieved higher in vitro release compared to respective design I, indicating that lower content of Acryl-EZE II® or Zein can decrease drug release over 3 h. It has been also revealed that Zein could improve physical stability of the aged theophylline solid-dispersed films. Release kinetics of model drugs were satisfactory when described by first-order kinetics, facilitated through anomalous transport of both diffusion and polymer swelling.

Preparation, Characterization and ex vivo Intestinal Permeability Studies of Ibuprofen Solid Dispersion

The aim of the present study was to improve the solubility and dissolution rate of ibuprofen and to evaluate, ex vivo, the intestinal permeation. Solid dispersions (SD) were prepared with Kollicoat IR® by solvent evaporation technique in different drug:carrier ratios. The permeation intestinal of ibuprofen was evaluated by inverted intestinal sac method. The SD was characterized by solubility equilibrium, FT-IR, DSC, PXRD, SEM, and dissolution rate. The solubility, dissolution rate, and permeability were significantly greater for SD 1:2. The PXRD, SEM and DSC indicated a partial change in the crystalline state of ibuprofen. The solubility equilibrium of SD (1:2) was approximately 15 times greater than the solubility of ibuprofen. Dissolution rate enhancement was attributed to the decreased crystallinity of the ibuprofen, and increase of wettability and decrease of particle size. In conclusion, dissolution rate and intestinal permeability of ibuprofen were enhanced by the use of Kollicoat IR® carrier in the SD formulation.

PET/CT imaging of 3D printed devices in the gastrointestinal tract of rodents

Fused deposition modelling (FDM) 3D printing (3DP) is a revolutionary technology with the potential to transform drug product design in both the pre-clinical and clinical arena. The objective of this pilot study was to explore the intestinal behaviour of four different polymer-based devices fabricated using FDM 3DP technology in rats. Small capsular devices of 8.6 mm in length and 2.65 mm in diameter were printed from polyvinyl alcohol-polyethylene glycol graft-copolymer (PVA-PEG copolymer, Kollicoat IR), hydroxypropylcellulose (HPC, Klucel), ethylcellulose (EC, Aqualon N7) and hypromellose acetate succinate (HPMCAS, Aquasolve-LG). A smaller sized device, 3.2 mm in length and 2.65 mm in diameter, was also prepared with HPMCAS to evaluate the cut off size of gastric emptying of solid formulations in rats. The devices were radiolabelled with Fluorodeoxyglucose (18F-FDG) and small animal positron emission tomography/computed tomography (microPET/CT) was used to track the movement and disintegration of the fabricated devices in the rats. The PVA-PEG copolymer and HPC devices disintegrated after 60min following oral administration. The EC structures did not disintegrate in the gastrointestinal tracts of the rats, whereas the HPMCAS-based systems disintegrated after 420 min. Interestingly, it was noted that the devices which remained intact over the course of the study had not emptied from the stomach of the rats. This was also the case with the smaller sized device. In summary, we report for the first time, the use of a microPET/CT imaging technique to evaluate the in vivo behaviour of 3D printed formulations. The manipulation of the 3D printed device design could be used to fabricate dosage forms of varying sizes and geometries with better gastric emptying characteristics suitable for rodent administration. The increased understanding of the capabilities of 3DP in dosage form design could, henceforth, accelerate pre-clinical testing of new drug candidates in animal models.

Tablet coating by injection molding technology – Optimization of coating formulation attributes and coating process parameters

We developed and evaluated a solvent-free injection molding (IM) coating technology that could be suitable for continuous manufacturing via incorporation with IM tableting. Coating formulations (coating polymers and plasticizers) were prepared using hot-melt extrusion and screened via stress-strain analysis employing a universal testing machine. Selected coating formulations were studied for their melt flow characteristics. Tablets were coated using a vertical injection molding unit. Process parameters like softening temperature, injection pressure, and cooling temperature played a very important role in IM coating processing. IM coating employing polyethylene oxide (PEO) based formulations required sufficient room humidity (>30% RH) to avoid immediate cracks, whereas other formulations were insensitive to the room humidity. Tested formulations based on Eudrajit E PO and Kollicoat IR had unsuitable mechanical properties. Three coating formulations based on hydroxypropyl pea starch, PEO 1,000,000 and Opadry had favorable mechanical (<700MPa Young’s modulus, >35% elongation, >95×104J/m3 toughness) and melt flow (>0.4g/min) characteristics, that rendered acceptable IM coats. These three formulations increased the dissolution time by 10, 15 and 35min, respectively (75% drug release), compared to the uncoated tablets (15min). Coated tablets stored in several environmental conditions remained stable to cracking for the evaluated 8-week time period.

Selective laser sintering (SLS) 3D printing of medicines

Selective laser sintering (SLS) 3-dimensional printing is currently used for industrial manufacturing of plastic, metallic and ceramic objects. To date there have been no reports on the use of SLS to fabricate oral drug loaded products; therefore, the aim of this work was to explore the suitability of SLS printing for manufacturing medicines. Two thermoplastic pharmaceutical grade polymers, Kollicoat IR (75% polyvinyl alcohol and 25% polyethylene glycol copolymer) and Eudragit L100-55 (50% methacrylic acid and 50% ethyl acrylate copolymer), with immediate and modified release characteristics respectively, were selected to investigate the versatility of a SLS printer. Each polymer was investigated with three different drug loadings of paracetamol (acetaminophen) (5, 20 and 35%). To aid the sintering process, 3% Candurin® gold sheen was added to each of the powdered formulations. In total, six solid formulations were successfully printed; the printlets (3D printed tablets) were robust, and no evidence of drug degradation was observed. In biorelevant bicarbonate dissolution media, the Kollicoat formulations showed pH-independent release characteristics, with the release rate dependent on the drug content. In the case of the Eudragit formulations, these showed pH-dependent, modified-release profiles independent of drug loading, with complete release being achieved over 12h. In conclusion, this work has demonstrated that SLS is a versatile and practical 3D printing technology which can be applied to the pharmaceutical field, thus widening the armamentarium of 3D printing technologies available for the manufacture of modern medicines.

Microencapsulation of chlorthalidone by spray-drying of double emulsion and melt granulation coating

ABSTRACTChlorthalidone (CH) is indicated in the management of hypertension either alone or in combination with other antihypertensive drugs, but it displays poor solubility and stability limiting its use in the development of new pharmaceutical alternatives. Spray-drying of double emulsions (SDE) and melt granulation coating (MGC) technologies were used for enhancing the stability of CH by using Eudragit® L30D-55 (EUD), Opadry® II (OPA), or Kollicoat® IR (KIR) as wall materials. SDE and MGC microcapsules containing CH were evaluated for particle size, morphology, release profiles, accelerated storage, and thermo-oxidative stability. Both types of microcapsules showed higher solubility (>80% in 20 min), lower degradation (<2%) under accelerated storage condition, and lower thermo-oxidative degradation than pure CH. However, SDE microcapsules showed smaller particle sizes (<16 µm) than MGC microcapsules (>700 µm), which widens the opportunity of incorporating microcapsules to dosage forms requiring different particle sizes for achieving their functionality.

Design and In-Vitro Evaluation of Colon Targeted Prednisolone Solid Dispersion Tablets

In the present investigation an attempt was made to prepare colon targeted enteric coated tablet containing different prednisolone solid dispersion formulations, to prevent ulcerative colitis, improve the patient compliance and reduce the side effects of drug in the gastro intestinal tract (GIT). Solid dispersion is one of the most widely used approaches to enhance the solubility as well as dissolution rate of poorly water soluble drugs. Solid dispersions (SDs) of Prednisolone with D-mannitol, PEG 4000 and Kollicoat IR were prepared and evaluated to deliver Prednisolone to the colon in a pre-solubilized form. The selected formula using drug compatible excipients was compressed into fast disintegrating tablets and then coated with Eudragit S100 (pH-responsive polymer), several variables related to both solid dispersion preparation (carrier type and drug to the carrier ratio) and tablet coating (coat level) were studied to show their effects on drug solubility and dissolution. Different analytical techniques like differential scanning caloremitry (DSC), powder x-ray diffraction (PXRD) and scanning electron microscopy (SEM) were studied to prove the change of drug particle from crystal to amorphous form in SDs. The 1:3 Prednisolone/Kollicoat IR SDs showed the greatest improvement in the dissolution rate. The coating level was critical for determining the duration of the lag phase. Best result was given by the 16% coat (Eudragit S100/ Dibutyl phthalate/ talc). This coating level showed an acceptable lag time for the proposed colonic targeting (5 h) as the selected tablet resisted pre-colonic pH values, followed by an immediate release stage in pH 7.4. The suggested covered (coated) tablets may provide a colonic delivery system for prednisolone with enhanced solubility and bioavailability.

New Easily Swallowed Tablets with Slippery Coating for the Antihypertensive Drug Valsartan

Different tablet dosage forms were prepared to be administered for patients with dysphagia (swallowing difficulties) like buccal, sublingual and orodispersible tablets, however, they possesses certain constrains like taste masking difficulties, limitations in drug and dose selection and friability. Hence, in an attempt to overcome these constrains, a new easily swallowed immediate release tablets containing (160mg) Valsartan were prepared, and designed to be slippery upon contact with saliva giving an easy swallowing of the intact tablet (without water) with efficient taste masking effect, thus, they called Oroslippery tablets (OSTs). Core tablets were prepared by direct compression using different superdisintegrants, followed by dipping in special coating dispersion containing different proportion of kollicoat IR (film former) and xanthan gum (slipperiness inducer) at different coating levels. These OSTs were optimized for their physical properties, in-vitro disintegration and release in addition to in-vivo slipperiness and taste masking effect. It was found that F12 containing 6% crosscarmellose sodium double coated with 15% kollicoat IR and 0.3% xanthan gum possessed a good mechanical strength (hardness=5.69±0.58 Kg/cm2, friability=0.09%±0.79), suitable in-vivo slipperiness and taste masking times (8±1.45 and 58±2.18 seconds) respectively, with longer disintegration time (5.57±1.36 minutes) but similar release profile to the commercial conventional tablet Diovan® with similarity factor (f2= 68.4±1.07) and difference factor (f1= 1.39± 0.95). Therefore, this study developed a new easily swallowed tablet with an efficient taste masking property, high loading capacity and adequate mechanical strength that can be used as an alternative to buccal, sublingual and orodispersible tablets.

Physicochemical properties of tadalafil solid dispersions – Impact of polymer on the apparent solubility and dissolution rate of tadalafil

To improve solubility of tadalafil (Td), a poorly soluble drug substance (3μg/ml) belonging to the II class of the Biopharmaceutical Classification System, its six different solid dispersions (1:1, w/w) in the following polymers: HPMC, MC, PVP, PVP-VA, Kollicoat IR and Soluplus were successfully produced by freeze-drying. Scanning electron microscopy showed a morphological structure of solid dispersions typical of lyophilisates. Apparent solubility and intrinsic dissolution rate studies revealed the greatest, a 16-fold, increase in drug solubility (50μg/ml) and a significant, 20-fold, dissolution rate enhancement for the Td/PVP-VA solid dispersion in comparison with crystalline Td. However, the longest duration of the supersaturation state in water (27μg/ml) over 24h was observed for the Td solid dispersion in HPMC. The improved dissolution of Td from Td/PVP-VA was confirmed in the standard dissolution test of capsules filled with solid dispersions. Powder X-ray diffraction and thermal analysis showed the amorphous nature of these binary systems and indicated the existence of dispersion at the molecular level and its supersaturated character, respectively. Nevertheless, as evidenced by film casting, the greatest ability to dissolve Td in polymer was determined for PVP-VA. The crystallization tendency of Td dispersed in Kollicoat IR could be explained by the low Tg (113°C) of the solid dispersion and the highest difference in Hansen solubility parameters (6.8MPa0.5) between Td and the polymer, although this relationship was not satisfied for the partially crystalline dispersion in PVP. Similarly, no correlation was found between the strength of hydrogen bonds investigated using infrared spectroscopy and the physical stability of solid dispersions or the level of supersaturation in aqueous solution.

Albendazole Microparticles Prepared by Spray Drying Technique: Improvement of Drug Dissolution

Purpose: To enhance the dissolution of albendazole (ABZ) using spray-drying technique. Method: ABZ binary mixtures with Kollicoat IR® (KL) and polyvinyl pyrrolidone (PVP) in various drug to polymer ratios (1: 1, 1: 2 and 1; 4) were prepared by spray-drying. The spray-dried particles were characterized for particle shape, and dissolution rate as well as by differential scanning calorimetry(DSC) and Fourier transform infrared (FTIR). Results: Scanning electron micrographs showed a homogeneous distribution of ABZ in the polymer matrix for ABZ-PVP spray-dried system in ratios of 1: 2 and 1: 4, while it was observed only upon using a ratio of ABZ: KL 1: 4 in case of ABZ-KL systems. FT-IR spectra of both physical mixtures and spraydried mixtures did not show any change for all ABZ-polymer systems, thus indicating the compatibility of the carriers with ABZ. ABZ exhibited a noticeable enhanced dissolution rate from its spray-dried coacervate with PVP and this was independent of the drug/polymer ratio. Drug release was 78, 81 and 81 % from the spray-dried ABZ-PVP systems of drug: polymer ratio of 1:1, 1:2 and 1: 4, respectively, within 5 min. Drug showed complete dissolution within 15 min. On the other hand, enhancement of dissolution rate varied with ABZ: Kl ratio. Conclusion: Enhancement of ABZ dissolution for both types of spray-dried particles is due to the reduction in drug particle sizes, wetting of the dissolution medium by the hydrophilic carriers and the amorphosization of the drug crystals by the carriers.

Polyvinyl acetate-based film coatings

Polyvinyl acetate-based colloidal aqueous polymer dispersion Kollicoat(®) SR 30 D results in coatings characterized by moderate swelling behaviour, lipophilicity, pH-independent permeability for actives and high flexibility to withstand mechanical stress and is therefore used for controlled release coating. The colloidal aqueous polymer dispersion of Kollicoat(®) SR 30 D can be easily processed due to an optimal low minimum film forming temperature (MFT) of 18 °C without plasticizer addition and a thermal after-treatment (curing) of coated pellets. The drug release from Kollicoat(®) SR 30 D coated pellets was almost pH independent. Drug release could be easily adjusted by coating level or addition of soluble pore forming polymers. Physically stable Kollicoat(®) SR 30 D dispersions were obtained with the water-soluble polymers Kollidon(®) 30 and Kollicoat(®) IR up to 50% w/w. The addition of only 10% w/w triethyl citrate as plasticizer improved the flexibility of the films significantly and allowed compaction of the pellets. The drug release was almost independent of the compression force and the pellet content of the tablets. The inclusion of various tableting excipients slightly affected the drug release, primarily because of a different disintegration rate of the tablets. A combination of Kollicoat(®) SR 30 D and Kollicoat(®) IR with higher coating levels>10 mg/cm(2) is a relatively new alternative to OROS system which does not require drilling.

Application of terahertz pulsed imaging to analyse film coating characteristics of sustained-release coated pellets

Terahertz pulsed imaging (TPI) was employed to explore its suitability for detecting differences in the film coating thickness and drug layer uniformity of multilayered, sustained-release coated, standard size pellets (approximately 1mm in diameter). Pellets consisting of a sugar starter core and a metoprolol succinate layer were coated with a Kollicoat(®) SR:Kollicoat(®) IR polymer blend for different times giving three groups of pellets (batches I, II and III), each with a different coating thickness according to weight gain. Ten pellets from each batch were mapped individually to evaluate the coating thickness and drug layer thickness between batches, between pellets within each batch, and across individual pellets (uniformity). From the terahertz waveform the terahertz electric field peak strength (TEFPS) was used to define a circular area (approximately 0.13 mm(2)) in the TPI maps, where no signal distortion was found due to pellet curvature in the measurement set-up used. The average coating thicknesses were 46 μm, 71 μm and 114 μm, for batches I, II and III respectively, whilst no drug layer thickness difference between batches was observed. No statistically significant differences in the average coating thickness and drug layer thickness within batches (between pellets) but high thickness variability across individual pellets was observed. These results were confirmed by scanning electron microscopy (SEM). The coating thickness results correlated with the subsequent drug release behaviour. The fastest drug release was obtained from batch I with the lowest coating thickness and the slowest from batch III with the highest coating thickness. In conclusion, TPI is suitable for detailed, non-destructive evaluation of film coating and drug layer thicknesses in multilayered standard size pellets.

Incorporation of Amphotericin B Into Self-Assembled Hydrophobized Kollicoat IR Nanoparticles

Kollicoat IR (KOL) is a new poly(ethylene glycol)-poly(vinyl alcohol) graft copolymer that is a promising material for medical applications because of its biocompatibility and hydrophilic nature. Amphotericin B (AmB) is a broad-spectrum fungicidal antibiotic used primarily in the treatment of life-threatening systemic fungal infections. However, AmB is limited in clinical use because of its poor water solubility. In this study, we synthesized AmB-loaded hydrophobized KOL nanoparticles for the first time. These self-assembled, stable nanoparticles exhibited a high AmB content. Among the hydrophobized KOL nanoparticles, a cholesterol-grafted KOL nanoparticle reduced AmB toxicity with respect to hemolysis and effectively increased the overall water solubility of AmB. Furthermore, a relatively high retention of AmB in the plasma was demonstrated in vivo in an animal experiment at early time after injection, suggesting that the cholesterol-grafted KOL nanoparticles could enable new pharmaceutical applications for AmB.

Dissolution enhancement of poorly soluble drug by solvent evaporation method using hydrophilic polymer: a solid dispersion technique

In order to investigate the effect of polymers on release mechanism of poorly soluble drugs from solid dispersions, Clonazepam was used as a model drug for these purposes. Five types of solid dispersions were prepared using polyethylene glycol 6000 (PEG- 6000), Kollicoat IR, Kollidon VA 64 and Poloxomer in different drug-tocarrier ratios (1:2, 1:4, 1:6, 1:8, 1:10). The solvent evaporation method was used for preparation of solid dispersions. The in-vitro dissolution study with temperature of 37° C and a paddle method, 100 rpm was used in 1000 ml of distilled water as dissolution medium in each dissolution basket for the pure drug and solid dispersions. For pure Clonazepam showed very slow dissolution rate and the solid dispersion considerably enhanced the dissolution rate. Decreased crystalline and increased amorphous fraction of the drug was probably done by wettability and dispersibility. The highest improvement in wettability and dissolution rate of Clonazepam was observed in PEG-6000, Poloxomer and Kollidon VA 64 (1:10 ratio). Solid dispersions containing polymer (1:10 ratio) prepared by solvent method showed significant improvement in the release profile as compared to pure drug, Clonazepam. DOI: http://dx.doi.org/10.3329/ijpls.v1i2.12952 International Journal of Pharmaceutical and Life Sciences Vol.1(2) 2012

Study of Binary and Ternary Solid Dispersion of Spironolactone Prepared By Co-Precipitation Method for the Enhancement of Oral Bioavailability

Article history: Received on: 07/10/2012 Revised on: 18/10/2012 Accepted on: 24/10/2012 Available online: 29/10/2012 The study was designed to formulate novel spironolactone, a BCS class II drug loaded solid dispersion system (SDs) with improved dissolution rate. For this purpose binary and ternary solid dispersion were prepared by co-precipitation method using Poloxamer-407 only and mixture of poloxamer-407 with a second polymer such as HPMC 6cps, HPC, Kollicoat IR, Kollidon VA 64 respectively. To prepare binary SDs poloxamer 407 was used in three concentrations: 33%, 50% and 66.67% wt/wt of total SDs, whereas in case of ternary SDs, poloxamer 407 was used at 15%, 25% 35% wt/wt of the total SDs content and the concentration of the second polymer is maintained at fixed amount (1gm). In vitro dissolution study was carried out in a USP type II dissolution apparatus in 0.1 N hydrochloric acid solution for 1 hour. Release property of spironolactone from two different SDs was examined. Both the systems showed improved release profile compared with pure spironolactone powder. Enhanced release of spironolactone from the optimized SDs was characterized in light of cumulative percent release, % release after 5 min of dissolution and release rate of the drug from different SDs. When the amount of carriers increased with a decrease in drug content, the release of spironolactone was elevated. And it was found that almost two fold increase in the release of spironolactone while 66.67% poloxamer was used.

COMPARATIVE IN VITRO DISSOLUTION STUDY OF SPIRONOLACTONE FROM BINARY AND TERTIARY SOLID DISPERSION: MODEL DEPENDANT AND INDEPENDENT APPROACHES

 Abstract: In this study solid dispersions (SDs) of spironolactone were prepared by solvent evaporation technique using poloxomer 407,  kollicoat IR, kollidon VA 64 and PEG 6000 as carrier. The solid dispersions were investigated for drug loading and dissolution behavior. Solid dispersions were found effective to enhance the solubility of spironolactone significantly in the dissolution media. Dissolution test was carried out purified water. Solid dispersion containing kollidon VA 64 at the ratio of 1:20, showed faster and higher drug release and was found most effective among all the solid dispersions. Drug carrier interactions were studied by comparing Fourier Transformed Infrared Spectroscopy (FT-IR) spectra of solid dispersions with pure drug and the SDs were found stable. Dissolution results of all the formulations were compared by using difference factor (f1), similarity factor (f2), dissolution efficiency (%DE) and multiple comparison Bonferroni test. No significant difference was found among the binary SDs containing 1:5 carrier, on the other hand all the ternary SDs were also found similar. So, solid dispersion technique may be an effective technique to enhance dissolution rate of spironolactone.

Gastroresistant capsular device prepared by injection molding

In the present work, the possibility of manufacturing by injection molding (IM) a gastro-resistant capsular device based on hydroxypropyl methyl cellulose acetate succinate (HPMCAS) was investigated. By performing as an enteric soluble container, such a device may provide a basis for the development of advantageous alternatives to coated dosage forms. Preliminarily, the processability of the selected thermoplastic polymer was evaluated, and the need for a plasticizer (polyethylene glycol 1500) in order to counterbalance the glassy nature of the molded items was assessed. However, some critical issues related to the physical/mechanical stability (shrinkage and warpage) and opening time of the device after the pH change were highlighted. Accordingly, an in-depth formulation study was carried out taking into account differing release modifiers potentially useful for enhancing the dissolution/disintegration rate of the capsular device at intestinal pH values. Capsule prototypes with thickness of 600 and 900 μm containing Kollicoat(®) IR and/or Explotab(®) CLV could be manufactured, and a promising performance was achieved with appropriate gastric resistance in pH 1.2 medium and break-up in pH 6.8 within 1h. These results would support the design of a dedicated mold for the development of a scalable manufacturing process.

The use of spray-drying to enhance celecoxib solubility

The present research investigates the enhancement of the dissolution rate of celecoxib by using spray-drying to prepare a solid dispersion with various polymers, namely Kollicoat IR® (Kollicoat), polyvinyl alcohol (PVA) 22000, or polyethylene glycol 6000 (PEG). The investigated drug-to-polymer mass ratios were 1:1, 1:2, and 1:4 by weight. Hydroalcoholic or methylene chloride solvent systems were used. The obtained yields ranged from 65% to 78%, whereas the entrapment efficiencies were between 68% and 82%. The results revealed an increase in the dissolution rate of the prepared particles up to 200% within 20 min. The prepared particles were investigated using differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The increased dissolution rate was attributed to hydrogen bond formation between celecoxib and each polymer together with the reduced size of the formed particles offering a greater overall surface area. It was concluded that spray-drying may be considered a successful one-step technique to improve the dissolution rate of celecoxib when using Kollicoat, PVA, or PEG as the carrier polymer.

Technology evaluation: Kollicoat IR

Introduction: Developments in industrial pharmacy are often linked to the discovery of pharmaceutical excipients. Although recently introduced as a material for immediate release coatings, Kollicoat IR already has other applications.Areas covered: In this review, the different properties and pharmaceutical applications of Kollicoat IR as an excipient are discussed. In the first part, the chemical structure and the physicochemical characteristics are examined. The second part is a presentation of the available Kollicoat IR products followed by a brief overview of the preclinical studies completed for its use as an instant release coating material.Expert opinion: Although the polymer was intended as an immediate release coating material for tablets, grafting PEG with polyvinyl alcohol to form this polymer provides physicochemical properties that lead to ever-broadening applications. Understanding its properties can lead to the development of a new use for Kollicoat IR. The addition of Kollicoat IR to an ethylcellulose or polyvinyl acetate tablet coat was successful at modifying the drug release rate. Designing a successful controlled release coat simply requires acknowledgment of the drug release mechanism from the mixture of polymers that includes Kollicoat IR. Moreover, the interaction between Kollicoat IR and poorly soluble drugs produces fast-dissolving solid dispersions prepared using hot stage extrusion, spray drying, or freeze drying.

Improvement of the in vitro release of omeprazole from suppository bases using Kollicoat IR

Solid dispersion of a slightly water soluble drug, omeprazole (OME), was prepared using different concentrations of Kollicoat IR by a spray drying technique. The physicochemical properties of the drug alone and its microparticles were investigated using differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD). The analyses showed that omeprazole transformed from the crystalline state to the amorphous state as confirmed by the disappearance of its melting peak and the characteristic of the crystalline peaks. Solid dispersion of the drug with this hydrophilic polymer was used in suppository formulations to investigate their role in enhancement drug release. The bases used in this study include hydrophilic base, polyethylene glycol (PEG), and lipophilic bases such as Suppocire AM and Witepsol H15. The release of omeprazole from a hydrophilic base was higher than that of a lipohilic base. Also, the release of drug from Supocire AM was superior to Witepsol H15. Incorporation of solid dispersion of drug using Kollicoat IR prepared by spray drying technique increases the release of OME from its suppository bases. The Kinetic study of the release of drug and its solid dispersion was carried out and the results indicated that the release of drug from different suppository bases is diffusion model.