Pelletized dosage forms can be prepared by different methods which, in general, are time consuming and labor intensive. The current study was carried out to investigate the feasibility of preparing the spherical pellets of omeprazole by sieving-spheronization. An optimized formulation was also prepared by extrusion-spheronization process to compare the physical parameters between these two methods. The omeprazole pellets were consisted of microcrystalline cellulose, polyvinylpyrrolidone K 30, sodium lauryl sulphate and polyethylene glycol 6000. The omeprazole delay release system was developed by coating the prepared pellets with aqueous dispersion of Kollicoat 30 DP. The moisture content, spheronization speed and residence time found to influence the final properties of omeprazole pellets prepared by extrusion-spheronization and sieving-spheronization. The Mann-Whitney test revealed that both methods produced closely similar characteristics of the pellets in terms of, friability (p=0.553), flowability (p=0.677), hardness (p=0.103) and density (bulk, p=0.514, tapped, p=0.149) except particle size distribution (p=0.004). The percent drug release from the coated formulation prepared by sieving-spheronization and extrusion spheronization was observed to be 84.12 ± 1.10% and 82.67 ± 0.96%, respectively. Dissolution profiles of both formulations were similar as indicated by values of f1 and f2, 1.52 and 89.38, respectively. The coated formulation prepared by sieving-spheronization and commercial reference product, Zimore ® also showed similar dissolution profiles (f1=1.22, f2=91.52). The pellets could be prepared using sieving-spheronization. The process is simple, easy, less time- and labor-consuming and economical as compared to extrusion-spheronization process.
The tableting properties of Labisia pumila herbal powder, which is well known for its therapeutic benefits was investigated. The herbal powder was compressed into tablets using a stainless steel cylindrical uniaxial die of 13-mm- diameter with compaction pressures ranging from 7 to 25 MPa. Two feed weights, 0.5 and 1.0 g were used to form tablets. Some empirical models were used to describe the compressibility behavior of Labisia pumila tablets. The strength and density of tablets increased with increase in compaction pressure and resulted in reduction in porosity of the tablets. Smaller feeds, higher forces and increase in compaction pressure, contributed to more coherent tablets. These findings can be used to enhance the approach and understanding of tableting properties of Labisia pumila herbal powder tablets.
The review focuses on the application of supercritical fluids as antisolvents in the pharmaceutical field and demonstrates the supercritical antisolvent method in the use of drug encapsulation. The main factors for choosing the solvent and biodegradable polymer to produce fine particles to ensure effective drug delivery are emphasized and the effect of polymer structure on drug encapsulation is illustrated. The review also demonstrates the drug release mechanism and polymeric controlled release system, and discusses the effects of the various conditions in the process, such as pressure, temperature, concentration, chemical compositions (organic solvents, drug, and biodegradable polymer), nozzle geometry, CO(2) flow rate, and the liquid phase flow rate on particle size and its distribution.
Orodispersible tablets disintegrate rapidly (within 3 minutes) in the oral cavity and release the medicament before swallowing. The mode of disintegrant addition might affect the properties of orodispersible tablets. The objective of this study was to formulate and evaluate orodispersible tablets by studying different modes of disintegration addition with varying concentrations of disintegrants. The wet granulation method was used to produce the orodispersible tablets. Two methods of disintegration addition were compared (i.e., intragranular, extragranular). Three disintegrants (i.e., cornstarch, sodium starch glycolate, crospovidone) were used at three levels (5%, 10%, and 15%) in the study. The formulations were tested for the powder flowability (angle of repose) and characterized physically (hardness, weight, thickness, friability, disintegration time). The mangosteen pericarp extract was used as a model active pharmaceutical ingredient to be incorporated into the optimum formulation. It was observed that the extragranular method produced granules with better flowability compared to that of the intragranular method. Crospovidone was found as the most efficient disintegrant among the three. The optimum formulation selected was one with the highest concentration of crospovidone (15%), which showed the fastest disintegration time. The mode of disintegrant addition into the orodispersible tablets formulation was found to show a marked difference in the disintegration, as well as other physical characteristics of the orodispersible tablets where the extragranular mode of addition showed better property, which caused the orodispersible tablets to disintegrate the fastest.
Nanoprecipitation is a simple and increasingly trending method for nanoparticles preparation. The self-assembly feature of poly (ethylene glycol)-poly (lactide-co-glycolic acid) (PEG-PLGA) amphiphilic copolymer into a nanoparticle and its versatile structure makes nanoprecipitation one of the best methods for its preparation. The aim of this study is to review currently available literature for standard preparation of PEG-PLGA nanoparticles using nanoprecipitation technique in order to draw conclusive evidenceto draw conclusive evidence that can guide researchers during formulation development. To achieve this, three databases (Web of Science, Scopus and PubMed) were searched using relevant keywords and the extracted articles were reviewed based on defined inclusion and exclusion criteria. Data extraction and narrative analysis of the obtained literature was performed when appropriate, along with our laboratory observations to support those claims wherever necessary. As a result of this analysis, reports that matched our criteria conformed to the general facts about nanoprecipitation techniques such as simplicity in procedure, low surfactants requirement, narrow size distribution, and low resulting concentrations. However, these reports showed interesting advantages for using PEG-PLGA as they are frequently reported to be freeze-dried and active pharmaceutical ingredients (APIs) with low hydrophobicity were reported to successfully be encapsulated in the particles.
We studied a model system of controlled drug release using beta-carotene and κ-carrageenan/NaCMC hydrogel as a drug and a device, respectively. Different concentrations of genipin were added to crosslink the beta-carotene loaded beads by using the dripping method. Results have shown that the cross-linked beads possess lower swelling ability in all pH conditions (pH 1.2 and 7.4), and swelling ratio decreases with increasing genipin concentration. Microstructure study shows that cross-linking has enhanced the stability and structure of the beads network. Determination of diffusion coefficient for the release of encapsulated beta-carotene indicates less diffusivity when beads are cross-linked. Swelling models using adaptive neuro fuzzy show that using genipin as a cross-linker in the kC/NaCMC hydrogels affects the transport mechanism. The model shows very good agreement with the experimental data that indicates that applying ANFIS modelling is an accurate, rapid and simple way to model in such a case for controlled release applications.
Microencapsulation of water-soluble drugs using coacervation-phase separation method is very challenging, as these drugs partitioned into the aqueous polymeric solution, resulting in poor drug entrapment. For evaluating the effect of ovalbumin on the microencapsulation of drugs with different solubility, pseudoephedrine HCl, verapamil HCl, propranolol HCl, paracetamol, and curcuminoid were used. In addition, drug mixtures comprising of paracetamol and pseudoephedrine HCl were also studied. The morphology, encapsulation efficiency, particle size, and in vitro release profile were investigated. The results showed that the solubility of the drug determined the ratio of ovalbumin to be used for successful microencapsulation. The optimum ratios of drug, ovalbumin, and gelatin for water-soluble (pseudoephedrine HCl, verapamil HCl, and propranolol HCl), sparingly water-soluble (paracetamol), and water-insoluble (curcuminoid) drugs were found to be 1:1:2, 2:3:5, and 1:3:4. As for the drug mixture, the optimum ratio of drug, ovalbumin, and gelatin was 2:3:5. Encapsulated particles prepared at the optimum ratios showed high yield, drug loading, entrapment efficiency, and sustained release profiles. The solubility of drug affected the particle size of the encapsulated particle. Highly soluble drugs resulted in smaller particle size. In conclusion, addition of ovalbumin circumvented the partitioning effect, leading to the successful microencapsulation of water-soluble drugs.
The objectives of the present work were to prepare castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulgator film and to assess the kinetic stability of the prepared cationic emulsion after subjecting it to thermal processing and freeze-thaw cycling. Presence of cryoprotectants (5%, w/w, sucrose +5%, w/w, sorbitol) improved the stability of emulsions to droplet aggregation during freeze-thaw cycling. After storing the emulsion at 4 degrees C, 25 degrees C, and 37 degrees C over a period of up to 6 months, no significant change was noted in mean diameter of the dispersed oil droplets. However, the emulsion stored at the highest temperature did show a progressive decrease in the pH and zeta potential values, whereas the emulsion kept at the lowest temperatures did not. This indicates that at 37 degrees C, free fatty acids were formed from the castor oil, and consequently, the liberated free fatty acids were responsible for the reduction in the emulsion pH and zeta potential values. Thus, the injectable castor oil-based nano-sized emulsion could be useful for incorporating various active pharmaceutical ingredients that are in size from small molecular drugs to large macromolecules such as oligonucleotides.
Modified-release multiple-unit tablets of loratadine and pseudoephedrine hydrochloride with different release profiles were prepared from the immediate-release pellets comprising the above two drugs and prolonged-release pellets containing only pseudoephedrine hydrochloride. The immediate-release pellets containing pseudoephedrine hydrochloride alone or in combination with loratadine were prepared using extrusion-spheronization method. The pellets of pseudoephedrine hydrochloride were coated to prolong the drug release up to 12 h. Both immediate- and prolonged-release pellets were filled into hard gelatin capsule and also compressed into tablets using inert tabletting granules of microcrystalline cellulose Ceolus KG-801. The in vitro drug dissolution study conducted using high-performance liquid chromatography method showed that both multiple-unit capsules and multiple-unit tablets released loratadine completely within a time period of 2 h, whereas the immediate-release portion of pseudoephedrine hydrochloride was liberated completely within the first 10 min of dissolution study. On the other hand, the release of pseudoephedrine hydrochloride from the prolonged release coated pellets was prolonged up to 12 hr and followed zero-order release kinetic. The drug dissolution profiles of multiple-unit tablets and multiple-unit capsules were found to be closely similar, indicating that the integrity of pellets remained unaffected during the compression process. Moreover, the friability, hardness, and disintegration time of multiple-unit tablets were found to be within BP specifications. In conclusion, modified-release pellet-based tablet system for the delivery of loratadine and pseudoephedrine hydrochloride was successfully developed and evaluated.
Khat (Catha edulis) is an evergreen tree/shrub that is thought to affect sexual motivation or libido. Its positive effect on sexual desire is more frequently observed in females than in males and occurs when khat is chewed. Thus, khat's effects on sexual behavior may depend on the release mode of its active constituent.
The susceptibility of probiotics to low pH and high temperature has limited their use as nutraceuticals. In this study, enhanced protection of probiotics via microencapsulation was achieved. Lactobacillus plantarum LAB12 were immobilised within polymeric matrix comprised of alginate (Alg) with supplementation of cellulose derivatives (methylcellulose (MC), sodium carboxymethyl cellulose (NaCMC) or hydroxypropyl methylcellulose (HPMC)). L. plantarum LAB12 encapsulated in Alg-HPMC(1.0) and Alg-MC(1.0) elicited improved survivability (91%) in simulated gastric conditions and facilitated maximal release (∼100%) in simulated intestinal condition. Alg-HPMC(1.0) and Alg-MC(1.0) significantly reduced (P 7 log CFU g-1. Alg-MC and Alg-HPMC improved the survival of LAB12 against simulated gastric condition (9.24 and 9.55 log CFU g-1, respectively), temperature up to 90 °C (9.54 and 9.86 log CFU g-1, respectively) and 4-week of storage at 4 °C (8.61 and 9.23 log CFU g-1, respectively) with sustained release of probiotic in intestinal condition (>9 log CFU g-1). These findings strongly suggest the potential of cellulose derivatives supplemented Alg bead as protective micro-transport for probiotic strains. They can be safely incorporated into new functional food or nutraceutical products.
In this research, the palm oil ester (POE)- based nanoemulsion formulation containing quercetin for pulmonary delivery was developed. The nanoemulsion formulation was prepared by high energy emulsification method and then further optimized using D-optimal mixture design. The concentration effects of the mixture of POE:ricinoleic acid (RC), ratio 1:1 (1.50-4.50 wt.%), lecithin (1.50-2.50 wt.%), Tween 80 (0.50-1.00 wt.%), glycerol (1.50-3.00 wt.%), and water (88.0-94.9 wt.%) towards the droplet size were investigated. The results showed that the optimum formulation with 1.50 wt.% POE:RC, 1.50 wt.% lecithin, 1.50 wt.% Tween 80, 1.50 wt.% glycerol and 93.90 % water was obtained. The droplet size, polydispersity index (PDI) and zeta potential of the optimized formulation were 110.3 nm, 0.290 and －37.7 mV, respectively. The formulation also exhibited good stability against storage at 4℃ for 90 days. In vitro aerosols delivery evaluation showed that the aerosols output, aerosols rate and median mass aerodynamic diameter of the optimized nanoemulsion were 99.31%, 0.19 g/min and 4.25 µm, respectively. The characterization of physical properties and efficiency for aerosols delivery results suggest that POE- based nanoemulsion containing quercetin has the potential to be used for pulmonary delivery specifically for lung cancer treatment.
Moringa oleifera leaves were selected as a model due to their hundreds of health benefits. On the other hand, the powder of these leaves has exhibited poor flowability, low tensile strength, bitter taste, poor dissolution rate, and lack of information regarding dosage. These are the common hurdles and limitations in the adaptation of herbal-based medications. Therefore, a comprehensive study was planned to introduce herbal-based medicines into mainstream medicines by standardization according to the U.S. Food and Drug Administration (FDA) and international pharmaceutical standards. A Simplex Lattice Design (SLD) of Design Expert 8.0 software was used to formulate different concentrations of superdisintegrant, binder/diluent, and sweeteners. An Instron Universal Testing machine coupled with a 13 mm stainless cylindrical die was used to manufacture tablets by means of direct compression method at 20 kN applied force. Therefore, selection of excipients was made on the basis of their tensile strength, flowability, and taste-masking properties. Optimum formulation was tested on rabbits for toxicity and growth rate. All formulated tablets were evaluated on standard parameters for orally disintegrating tablets described by the Food and Drug Authority (U.S.). The optimum formulation fulfills all standard parameters such as hardness, disintegration time, friability, and dissolution rate. The present formulation showed no toxicity when tested on rabbits. The present study provides a fundamental understanding of the tableting characteristics of natural medicines. The present study provides information that will help to overcome the challenges.
Efficient delivery of adequate active ingredients to targeted malignant cells is critical, attributing to recurrent biophysical and biochemical challenges associated with conventional pharmaceutical delivery systems. These challenges include drug leakage, low targeting capability, high systemic cytotoxicity, and poor pharmacokinetics and pharmacodynamics. Targeted delivery system is a promising development to deliver sufficient amounts of drug molecules to target cells in a controlled release pattern mode. Aptameric ligands possess unique affinity targeting capabilities which can be exploited in the design of high pay-load drug formulations to navigate active molecules to the malignant sites. This study focuses on the development of a copolymeric and multifunctional drug-loaded aptamer-conjugated poly(lactide-co-glycolic acid)-polyethylenimine (PLGA-PEI) (DPAP) delivery system, via a layer-by-layer synthesis method, using a water-in-oil-in-water double emulsion approach. The binding characteristics, targeting capability, biophysical properties, encapsulation efficiency, and drug release profile of the DPAP system were investigated under varying conditions of ionic strength, polymer composition and molecular weight (MW), and degree of PEGylation of the synthetic core. Experimental results showed increased drug release rate with increasing buffer ionic strength. DPAP particulate system obtained the highest drug release of 50% at day 9 at 1 M NaCl ionic strength. DPAP formulation, using PLGA 65:35 and PEI MW of ∼800 Da, demonstrated an encapsulation efficiency of 78.93%, and a loading capacity of 0.1605 mg bovine serum albumin per mg PLGA. DPAP (PLGA 65:35, PEI MW∼25 kDa) formulation showed a high release rate with a biphasic release profile. Experimental data depicted a lower targeting power and reduced drug release rate for the PEGylated DPAP formulations. The outcomes from the present study lay the foundation to optimize the performance of DPAP system as an effective synthetic drug carrier for targeted delivery.
There has been an explosion of probiotic incorporated based product. However, many reports indicated that most of the probiotics have failed to survive in high quantity, which has limited their effectiveness in most functional foods. Thus, to overcome this problem, microencapsulation is considered to be a promising process. In this study, Lactococcus lactis Gh1 was encapsulated via spray-drying with gum Arabic together with Synsepalum dulcificum or commonly known as miracle fruit. It was observed that after spray-drying, high viability (~10⁸ CFU/mL) powders containing L. lactis in combination with S. dulcificum were developed, which was then formulated into yogurt. The tolerance of encapsulated bacterial cells in simulated gastric juice at pH 1.5 was tested in an in-vitro model and the result showed that after 2 h, cell viability remained high at 1.11 × 10⁶ CFU/mL. Incubation of encapsulated cells in the presence of 0.6% (w/v) bile salts showed it was able to survive (~10⁴ CFU/mL) after 2 h. Microencapsulated L. lactis retained a higher viability, at ~10⁷ CFU/mL, when incorporated into yogurt compared to non-microencapsulated cells ~10⁵ CFU/mL. The fortification of microencapsulated and non-microencapsulated L. lactis in yogurts influenced the viable cell counts of yogurt starter cultures, Lactobacillus delbrueckii subs. bulgaricus and Streptococcus thermophilus.
The different states of water incorporated in wet granules were studied by a low-field benchtop 1H-NMR time-domain NMR (TD-NMR) instrument. Wet granules consisting different fillers [cornstarch (CS), microcrystalline cellulose (MCC), and D-mannitol (MAN)] with different water contents were prepared using a high-speed granulator, and then their spin-spin relaxation time (T2) was measured using the NMR relaxation technique. The experimental T2 relaxation curves were analyzed by the two-component curve fitting, and then the individual T2 relaxation behaviors of solid and water in wet granules were identified. According to the observed T2 values, it was confirmed that the molecular mobility of water in CS and MCC granules was more restricted than that in the MAN granule. The state of water appeared to be associated with the drying efficiency and moisture absorption capacity of wet granules. Thus, it was confirmed that the state of water significantly affected the wet granulation process and the characteristics of the resultant granules. In the final phase of this study, the effects of binders on the molecular mobility of water in granulation fluids and wet granules were examined. The state of water in granulation fluids was substantially changed by changing the binders. The difference was still detected in wet granules prepared by addition of these fluids to the fillers. In conclusion, TD-NMR can offer valuable knowledge on wet granulation from the viewpoint of molecular mobility of water.
Electrodeposition is commonly used to deposit ceramic or metal coating on metallic implants. Its utilization in depositing polymer microcapsule coating is currently being explored. However, there is no encapsulation of drug within polymer microcapsules that will enhance its chemical and biological properties. Therefore, in this study, ginseng which is known for its multiple therapeutic effects was encapsulated inside biodegradable poly(lactic-co-glycolic acid) (PLGA) microcapsules to be coated on pre-treated medical grade stainless steel 316L (SS316L) using an electrodeposition technique. Polyaniline (PANI) was incorporated within the microcapsules to drive the formation of microcapsule coating. The electrodeposition was performed at different current densities (1-3 mA) and different deposition times (20-60 s). The chemical composition, morphology and wettability of the microcapsule coatings were characterized through attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM) and contact angle analyses. The changes of electrolyte colors, before and after the electrodeposition were also observed. The addition of PANI has formed low wettability and uniform microcapsule coatings at 2 mA current density and 40 s deposition time. Reduction in the current density or deposition time caused less attachment of microcapsule coatings with high wettability records. While prolonging either one parameter has led to debris formation and melted microcapsules with non-uniform wettability measurements. The color of electrolytes was also changed from milky white to dark yellow when the current density and deposition time increased. The application of tolerable current density and deposition time is crucial to obtain a uniform microcapsule coating, projecting a controlled release of encapsulated drug.
It is generally accepted that the tablet elastic relaxation during compaction plays a vital role in undermining the final tablet mechanical integrity. One of the least investigated stages of the compaction process is the ejection stage.