Screening Of Excipients Research Articles

Optimizing rosemary oil nanoemulsion loaded with nelfinavir and epigallocatechin gallate: A Design Expert® endorsed approach for enhanced neuroAIDS management

This study focuses on optimizing the delivery of Nelfinavir (NFV), a vital protease inhibitor in antiretroviral therapy, and Epigallocatechin gallate (EGCG), a potent adjunctive anti- human immunodeficiency virus (anti-HIV) agent found in green tea. The challenge lies in NFV's low intrinsic dissolution rate, significant p-gp efflux, and high hepatic metabolism, necessitating frequent and high-dose administration. Our objective was to develop a nanoemulsion loaded with NFV and EGCG to enhance oral delivery, expediting antiretroviral effects for NeuroAIDS treatment. After meticulous excipient screening, we selected Tween 40 as the surfactant and polyethylene glycol 400 (PEG 400) as the co-surfactant. Employing a Quality by Design (QbD) approach with statistical multivariate methods, we optimized the nanoemulsion that exhibited a droplet size of 83.21 nm, polydispersity index (PDI) of 2.289, transmittance of 95.20 %, zeta potential of 1.495 mV, pH of 6.95, refractive index of 1.40, viscosity of 24.00 ± 0.42 mPas, and conductivity of 0.162 μS/cm. Pharmacokinetic studies demonstrated superior in vivo absorption of the optimized nanoemulsion compared to NFV and EGCG suspension. The optimized nanoemulsion showcased higher Cmax of NFV (9.75 ± 1.23 μg/mL) and EGCG (27.7 ± 1.22 μg/mL) in the brain, along with NFV (26.44 ± 1.44 μg/mL) and EGCG (313.20 ± 5.53 μg/mL) in the plasma. This study advocates for the potential of NFV and EGCG-loaded nanoemulsion in combination antiretroviral therapy (cART) for effective NeuroAIDS management.

Development of a fluorescence-based excipient screening for improved stability and shelf-life of recombinant chitin deacetylase

Chitin deacetylase (CDA) modifies chitin into chitosan by removing acetyl groups, but its inherent instability poses a challenge for successful crystallisation. Despite limited successes in crystallizing CDAs, prior attempts with recombinant chitin deacetylase (BaCDA) failed due to poor stability. To address this, we propose an enzyme buffer formulation as a cost-effective strategy to enhance stability, prolong shelf life, and increase the likelihood of crystallisation. Utilizing the high-throughput screening technique FTSA, we developed a screening method correlating BaCDA stability with its activity. The optimised formulation comprises 50 mM Tris-HCl buffer pH 7, 1 M NaCl, 20 % glycerol, and 1 mM Mg2+ as excipients. This formulation significantly improves BaCDA's thermostability (140.47 % increase) and enzyme activity (2.9-fold enhancement). BaCDA remains stable in the formulated buffer at −20 °C and −80 °C for 30 days and at 4 °C for 15 days. The current study has designed a high-throughput screening method approach to assess the stability of CDA enzyme formulations. The results of this study could contribute to the exploration of formulation elements that enhance the structural stability of CDA, thereby facilitating investigations into the enzyme's structure-function relationships.

Ternary solid dispersions of lacidipine: Enhancing dissolution and supersaturation maintenance through strategic formulation optimization

The study aimed to address the challenges related to insufficient dissolution and maintenance of supersaturation in binary solid dispersions. Lacidipine, categorized as a BCS class II drug, was employed as the model drug. A systematic screening of excipients was conducted to determine the most effective carriers for the formulations of the ternary solid dispersions, utilizing the solvent transfer method and equilibrium solubility measurements. Both binary and ternary solid dispersions were prepared via spray drying, and comprehensive physicochemical characterization confirmed the successful preparation of amorphous solid dispersions. In vitro dissolution tests, the ternary solid dispersion exhibited marked superiority over the binary solid dispersion in dissolution and maintenance of supersaturation. Furthermore, an exploration into the factors influencing the stability of ternary solid dispersions revealed their robust resistance under light-protected, room-temperature, and desiccated conditions. The formation of intermolecular hydrogen bonding within the molecules of the ternary solid dispersions significantly enhanced drug solubility and system stability. Strategic formulation optimization, coupled with judicious selection of suitable carrier types and ratios, may serve as a promising approach for designing supersaturated drug delivery systems.

Screening of Organic Small Molecule Excipients on Ternary Solid Dispersions Based on Miscibility and Hydrogen Bonding Analysis: Experiments and Molecular Simulation.

The preparation of solid dispersions by mixing insoluble drugs with polymers is the main way to improve the aqueous solubility of drugs. The introduction of organic small molecule excipients into binary solid dispersions is expected to further enhance drug solubility by regulating intermolecular hydrogen bonding within the system at the microscopic level. In this study, we used carbamazepine (CBZ) as the target drug and polyvinylpyrrolidone as the solid dispersion matrix and screened the third component from 13 organic small molecules with good miscibility in the solid dispersion based on the principle of similarity of solubility parameters. The hydrogen bonding parameters and dissociation Gibbs free energy of the 13 organic small molecule-CBZ dimer were calculated by quantum mechanical simulation, and the tryptophan (Try) was identified as the optimal third component of organic small molecule. The migration of CBZ in binary and ternary systems was also analyzed by molecular dynamics simulation. On this theoretical basis, the corresponding solid dispersions were prepared, characterized, and tested for solubility analysis, which verified that the drug solubility was stronger for the system with the addition of polar fractions and the Try was indeed the best third component of organic small molecule compound, which was consistent with the simulation predictions. This screening method may provide theoretical guidance for drug modification design and clinical studies.

A Rapid 3-Day Excipient Screening Methodology and its Application in Identifying Chemical Stabilizers for Solid Formulations with Mixed Mechanisms of Degradation.

This study outlines a practical approach for assessing chemical instability by heating the drug-excipient binary mixtures or multi-excipient formulations at 75°C for 3days before characterization. Differentiating itself from other excipient compatibility methods, our methodology necessitates a saturated aqueous slurry rather than arbitrarily fixed water content. This allows bulk and surface water in the excipient to contribute to drug degradation. The synergistic impact of surface water and elevated temperature expedites degradation kinetics, resulting in accelerated data generation. Among excipient compatibility methods available, our method is quantitative and merges with traditionally used methodologies. The devised nomograph enables extrapolation of shelf life at 20°C from experimental data obtained at 75°C. This methodology also helped identify stabilizers for the drug NVS-1 where traditional excipient compatibility programs had failed. Incorporation of monovalent salts, such as sodium/potassium chloride and sodium bicarbonate at 5% w/w, significantly enhanced the chemical stability of NVS-1, ensuring stable tablet formulations. Our hypothesis posits that stabilization is due to increased ionic strength in the slurry, which stabilizes an induced dipole within the polar NVS-1 drug. Additionally, the presence of ions in the moisture layer is anticipated to stabilize π-π stacking of two planar aromatic NVS-1 molecules. The expedited generation of experimental data allowed the identification of inorganic salts to supplement a standard excipient compatibility screening panel. Considering the economic implications of stability testing methodologies in effort, cost, and duration, a faster turnaround in chemical stability data enhances formulation selection. This ultimately facilitates the development of drug formulations with greater efficiency without delays.

Rapid screening of ternary amorphous formulations by a spray drying robot

Spray drying is commonly used for producing amorphous solid dispersions to improve drug solubility. The development of such formulations typically relies on comprehensive excipient and composition screening, which requires the preparation of many spray-dried powder samples. This is both labour-intensive and time-consuming when carried out manually. In the present work, the formulation screening task was automated by coupling a laboratory spray dryer operated in a semi-continuous mode with custom-made add-ons, allowing for rapid, computer-controlled production of formulation samples with systematically varying composition. The practical use of the spray drying robot in formulation development was demonstrated on a case study of poorly water-soluble model drugs simvastatin and ezetimibe. Six different polymers and several drug:polymer ratios were screened for the enhancement of dissolution properties. From a pool of 28 spray-dried samples, ternary compositions containing Eudragit L100-55 were identified as the most suitable ones for further processing and characterisation. The ability to populate the formulation design space rapidly and automatically made it possible to construct maps of physico-chemical properties such as glass transition temperature or dissolution rate. The spray drying robot thus enables the acceleration of early formulation development and a deeper understanding of composition-property relationships for multi-component spray dried powders.

Development of an amoxicillin-radix scutellaria extract formulation and evaluation of its pharmacokinetics in pigs

BackgroundA new antibacterial compound powder of amoxicillin (AMO)/Radix Scutellaria extract (RSE) was developed, and its pharmacokinetics were determined in pigs following oral administration.ResultsThe MIC ranges of AMO against Escherichia coli, Staphylococcus aureus and Streptococcus were 1–8 μg/mL, 0.5–4 μg/mL and 0.5–64 μg/mL, respectively. The MIC ranges of RSE against E. coli, S. aureus, and Streptococcus were greater than 2.5 mg/mL, 0.156–2.5 mg/mL, and greater than 2.5 mg/mL, respectively. For S. aureus, the combined drug susceptibility test showed that AMO and RSE had an additive or synergistic effect. The results of compatibility test, the excipient screening test and the drug quality control test showed that the formulation had stable quality and uniform properties under the test conditions. Two studies were conducted to investigate the pharmacokinetics of the compound product in pigs. First, the pharmacokinetics of the AMO-RSE powder were compared with those of their respective single products. The results showed no significant change in the main pharmacokinetic parameters when either component was removed from the compound formulation; thus, AMO and RSE have no pharmacokinetic interaction in pigs. Second, pigs were orally administered three different doses of AMO-RSE powder. The Cmax and AUC increased proportionally with increasing p.o. dose; thus, the λz, t1/2λ, MRT, and Tmax were unchanged for the doses of 10, 20, and 30 mg/kg AMO and the doses of 5, 10, and 15 mg/kg BCL, showing that AMO/baicalin in AMO-RSE powder showed linear pharmacokinetic characteristics in pigs.ConclusionsThe combined drug sensitivity test of AMO and RSE against S. aureus showed that the combination was additive or synergistic. Pharmacokinetic studies indicated that AMO and BCL do not interfere with each other in pigs when used in a compound formulation. The pharmacokinetic parameters remained unchanged regardless of the dose for p.o. administration, indicating linear pharmacokinetic properties over the tested dose range. The quality of the AMO-RSE powder was good and stable, providing a foundation for its clinical application in veterinary medicine. Further bioavailability, PK/PD and clinical trials are still needed to determine the final dosage regimen.

Stability of Monoclonal Antibodies as Solid Formulation for Auto-Injectors: A Pilot Study.

Drug adherence is a significant medical issue, often responsible for sub-optimal outcomes during the treatment of chronic diseases such as rheumatoid or psoriatic arthritis. Monoclonal antibodies (which are exclusively given parenterally) have been proven to be an effective treatment in these cases. The use of auto-injectors is an effective strategy to improve drug adherence in parenteral treatments since these pen-like devices offer less discomfort and increased user-friendliness over conventional syringe-based delivery. This study aims to investigate the feasibility of including a monoclonal antibody as a solid formulation inside an auto-injector pen. Specifically, the objective was to evaluate the drug stability after a concentration (to reduce the amount of solvent and space needed) and freeze-drying procedure. A preliminary screening of excipients to improve stability was also performed. The nano-DSC results showed that mannitol improved the stability of the concentrated, freeze-dried antibody in comparison to its counterpart without it. However, a small instability of the CH2 domain was still found for mannitol samples, which will warrant further investigation. The present results serve as a stepping stone towards advancing future drug delivery systems that will ultimately improve the patient experience and associated drug adherence.

Drug-Excipient Compatibility Study Through a Novel Vial-in-Vial Experimental Setup: A Benchmark Study.

Drug-excipient compatibility study (DECS) is one of the critical steps during pre-formulation studies to select the appropriate excipient to obtain a stable formulation/dosage form. As such, there is no recommended guideline for DECS. Further, the previously reported studies and protocols followed by various pharmaceutical industries are very lengthy and laborious. Therefore, to improve the existing study strategies and rapid screening of suitable excipients during formulation development, a novel vial-in-vial approach has been proposed. The devised approach was compared with the previously reported conventional approaches using six different drugs with multiple marketed formulations from different manufacturers for each drug. To validate the proposed novel approach, several reported strategies/methodologies have been executed such as exposure of formulations with and without primary packaging, crushed blend with and without water, and/or acetonitrile at accelerated stability condition of 40°C/75% RH for 3 to 6months and compared with the novel approach. Eventually, all the samples were subjected to HPLC analysis to evaluate the degradation behaviour. The results suggested that the novel approach demonstrated discriminating results with significant degradation as compared to the conventional approaches. Consequently, exercising this methodology for screening the excipients is expected to shorten the drug development cycle by many folds. Moreover, it has also been anticipated that the developed novel approach would prevent the occurrence of late-stage surprises during stability studies.

Thermodynamic Mechanism of Physical Stability of Amorphous Pharmaceutical Formulations

Hygroscopicity is an important factor affecting the physical stability of amorphous solid dispersions (ASDs) during long-term storage. In this work, the effects of temperature, relative humidity (RH), and polymeric excipients on the phase behavior of amorphous irbesartan (IRB) and oxaprozin (OXA) were systematically investigated. The ASDs were prepared by the solvent evaporation method. The water sorption in formulations was measured under the conditions of 25 °C, 60% RH, 25 °C, 90% RH, and 40 °C, 75% RH. The results showed that the hygroscopicity of formulations containing polyvinylpyrrolidone (PVP) was stronger than that containing poly(vinylpyrrolidone-co-vinyl acetate) (PVPVA 46) and the hygroscopicity increased with increasing temperature and RH. With increasing content of active pharmaceutical ingredients (APIs), the recrystallization phenomenon is significant at the same RH. PVP can better inhibit IRB recrystallization than PVPVA 46. In contrast, PVPVA 46 can better maintain the amorphous form of OXA than PVP. The thermodynamic phase diagrams of amorphous API/polymer formulations at 60% RH and anhydrous conditions were predicted using perturbed chain statistical associated fluid theory (PC-SAFT) and the Gordon–Taylor equation. Furthermore, the electrostatic potential (ESP) and binding energies between APIs and polymers were calculated with density functional theory (DFT), which explained the molecular interaction mechanism of ASDs. This work is expected to guide the screening of excipients and API loadings for designing ASDs and the selection of storage conditions.

In vitro screening of topical formulation excipients for epithelial toxicity in cancerous and non-cancerous cell lines.

Chemical excipients used in topical formulations may be toxic to living skin cells. Here, we compared the in vitro toxicity of some common solubilizing excipients against human melanoma cells, human keratinocytes (HaCaT) and primary skin fibroblasts (FB) as examples of cancerous, immortalized and primary human skin cells, often used as experimental models representative of in vivo conditions. Two distinct endpoint assays (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet (CV)) were used. The mechanism of cell death after excipient exposure was assessed through Reactive Oxygen Species (ROS) production, cell membrane integrity and cell cycle progression. Results showed that the surfactants, Labrasol®, Labrafil® and Transcutol®, were less toxic than Triton X-100 (a model irritant) in all cell types whereas the oil, Labrafac®, was non-toxic. The human melanoma WM164 cell line showed the greatest sensitivity toward cytotoxicity after chemical exposure, while the other cell lines were more resistant. The relative excipient cytotoxicity responses observed in the MTT and CV assays were comparable and similar trends were seen in their estimated 50 % inhibitory concentration (IC50) values. DNA fragmentation by flow cytometry after exposing the cells to IC50 concentrations of the excipients showed negligible apoptotic populations. ROS production was increased in all cell types after toxic exposure; however, ROS elevation did not lead to apoptosis. The toxicity profiles of each excipient are not only relevant to their use in formulating safe topical products but also in the potential synergistic efficacy in the topical treatment of melanoma.

High-throughput kinetic turbidity analysis for determination of amorphous solubility and excipient screening for amorphous solid dispersions

Many poorly water-soluble active pharmaceutical ingredients (APIs) rely on supersaturating formulations, such as amorphous solid dispersions (ASDs), to enhance oral bioavailability. ASDs kinetically trap amorphous solid drugs within polymer excipient matrices to maintain the amorphous drug states. The maximum solution concentration of the API in these formulations is known as the amorphous solubility. In early drug development with scarce material and time, high-throughput approaches to measuring amorphous solubility and screening excipient effects on crystallization risk offer significant benefits to preclinical formulation scientists. Here, we developed a high-throughput screening (HTS) workflow to quantify amorphous solubility and screen ASD excipients by automated kinetic turbidity analysis. Testing 20 model APIs with a wide range of biorelevant solubility, we demonstrated their apparent amorphous solubility determined by the HTS approach strongly correlated with quantification results using conventional liquid chromatography; while the real-time analysis significantly saved analytical time and experimental efforts. Furthermore, kinetic turbidity profiles elucidated distinct excipient effects on the precipitation process of APIs. These results were successfully translated to dissolution and precipitation behaviors of ASD formulations composed of the tested polymers. The high-throughput kinetic turbidity workflow presents a facile and information-rich approach for amorphous solubility screenings against excipients, and helps guide enabling formulation development.

Tadalafil Nanoemulsion Mists for Treatment of Pediatric Pulmonary Hypertension via Nebulization.

Oral tadalafil (TD) proved promising in treating pediatric pulmonary arterial hypertension (PAH). However, to ensure higher efficacy and reduce the systemic side effects, targeted delivery to the lungs through nebulization was proposed as an alternative approach. This poorly soluble drug was previously dissolved in nanoemulsions (NEs). However, the formulations could not resist aqueous dilution, which precluded its dilution with saline for nebulization. Thus, the current study aimed to modify the previous systems into dilutable TD-NEs and assess their suitability for a pulmonary application. In this regard, screening of various excipients was conducted to optimize the former systems; different formulations were selected and characterized in terms of physicochemical properties, nebulization performance, stability following sterilization, and biocompatibility. Results showed that the optimal system comprised of Capmul-MCM-EP:Labrafac-lipophile (1:1) (w/w) as oil, Labrasol:Poloxamer-407 (2:1) (w/w) as surfactant mixture (Smix) and water. The optimum formulation P2TD resisted aqueous dilution, exhibited reasonable drug loading (2.45 mg/mL) and globule size (25.04 nm), acceptable pH and viscosity for pulmonary administration, and could be aerosolized using a jet nebulizer. Moreover, P2TD demonstrated stability following sterilization and a favorable safety profile confirmed by both in-vitro and in-vivo toxicity studies. These favorable findings make P2TD promising for the treatment of pediatric PAH.

Selecting the most appropriate formulation excipient for manufacture of amorphous solid dispersions: a case study of lumefantrine

This work demonstrated the importance of pre-formulation studies and proposed a generalised scheme for excipient screening in the early stage of amorphous solid dispersion(ASD) system development by profiling the excipients’ capability to solubilise, amorphisise, and stabilise the chosen active pharmaceutical ingredient (API) in an effort to rank their suitability. Lumefantrine, an antimalarial active compound with both poor solubility and permeability, was used as a model API and solvent evaporation film casting was used to prepare the candidate ASD matrices in this work. 

FORMULATION AND EVALUATION OF MEDICATED CHEWING GUM OF EGCG (EPIGALLOCATECHIN GALLATE) ENRICHED EXTRACT OF CAMELLIA SINENSIS (GREEN TEA) FOR PERIODONTAL DISEASE

The aim of this study was the formulation and evaluation of medicated chewing gum of EGCG (epigallocatechin gallate) enriched extract of camellia sinensis. The extraction of marketed lipton green tea was done by infusion method and antibacterial activities of extract were done against P. gingivalis and S. mutan by well diffusion method. Chewing gum was prepared by softening of gum bases and then mixing with other formulation ingredients and optimization of the formulation by screening of different excipients. Performance evaluation was carried out by evaluating hardness, fracturability, adhesiveness, elasticity, cohesiveness, stringiness, chewiness, gumminess, in vivo drug release study. Precentage yield of extract in first step and second step were found to be 9.43, 11.65 respectively by infusion method. The EGCG obtained with second step of two step method was found significantly greater. In antibacterial activities, the glucan synthesis by the bacterial S. mutan glucosyl transferase was strongly inhibited by (-)-epigallocatechin gallate (EGCG) at concentrations of 50-200ug/ml, the main components of the green tea polyphenols and completely inhibited the growth and adherence of P. gingivalis onto the buccal epithelial cells. Optimized formulations MCG-6 showed hardness, adhesiveness, elasticity, gumminess, chewiness, resilience and cohesiveness values are similar to that of the reference (Nicogum). In vitro drug released of optimized formulation was found to be 77% within 15 min. The developed formulation of medicated chewing gum can be a better alternative to mouth dissolving and conventional tablet formulation. It may be proved as a promising approach to improve the bioavailability as well as to improve patient compliance.

Technology development to evaluate the effectiveness of viscosity reducing excipients

Addition of pharmaceutical excipients is a commonly used approach to decrease the viscosity of highly concentrated protein formulations, which otherwise could not be subcutaneously injected or processed. The variety of protein–protein interactions, which are responsible for increased viscosities, makes a portfolio approach necessary. Screening of several excipients to develop such a portfolio is time and money consuming in industrial settings.Responsible protein–protein interactions were investigated using the interaction parameter kD obtained from dynamic light scattering measurements in the studies presented herein. Together with in-silico calculated excipient parameter, kD could be used as a screening tool accelerating screening and formulation development as kD is suitable to high-throughput formats using small quantities of protein and low concentrations. A qualitative correlation between kD and high-concentration viscosity behavior could be shown in our case.

Study on the Effect of Polymer Excipients on the Dispersibility, Interaction, Solubility, and Scavenging Reactive Oxygen Species of Myricetin Solid Dispersion: Experiment and Molecular Simulation.

Although the preparation of amorphous solid dispersions can improve the solubility of crystalline drugs, there is still a lack of guidance on the micromechanism in the screening and evaluation of polymer excipients. In this study, a particular method of experimental characterization combined with molecular simulation was attempted on solubilization of myricetin (MYR) by solid dispersion. According to the analysis of the dispersibility and hydrogen-bond interaction, the effectiveness of the solid dispersion and the predicted sequence of poly(vinyl pyrrolidone) (PVP) > hypromellose (HPMC) > poly(ethylene glycol) (PEG) as the polymer excipient were verified. Through the dissolution, cell viability, and reactive oxygen species (ROS)-level detection, the reliability of simulation and micromechanism analysis was further confirmed. This work not only provided the theoretical guidance and screening basis for the miscibility of solid dispersions from the microscopic level but also served as a reference for the modification of new drugs.

In Vitro Evaluation of a Solid Supersaturated Self Nanoemulsifying Drug Delivery System (Super-SNEDDS) of Aprepitant for Enhanced Solubility.

Aprepitant (APR) belongs to Class II of the Biopharmaceutical Classification System (BCS) because of its low aqueous solubility. The objective of the current work is to develop self-nanoemulsifying drug delivery systems (SNEDDS) of APR to enhance its aqueous solubility. Preformulation studies involving screening of excipients for solubility and emulsification efficiency were carried out. Pseudo ternary phase diagrams were constructed with blends of oil (Imwitor® 988), cosolvent (Transcutol® P), and various surfactants (Kolliphor® RH40, Kolliphor® ELP, Kolliphor® HS15). The prepared SNEDDS were characterized for droplet size and nanoemulsion stability after dilution. Supersaturated SNEDDS (super-SNEDDS) were prepared to increase the quantity of loaded APR into the formulations. HPMC, PVP, PVP/VA, and Soluplus® were used as polymeric precipitation inhibitors (PPI). PPIs were added to the formulations at 5% and 10% by weight. The influence of the PPIs on drug precipitation was investigated. In vitro lipolysis test was carried out to simulate digestion of formulations in the gastrointestinal tract. Optimized super-SNEDDS were formulated into free-flowing granules by adsorption on the porous carriers such as Neusilin® US2. In vitro dissolution studies of solid super-SNEDDS formulation revealed an increased dissolution rate of the drug due to enhanced solubility. Consequently, a formulation to improve the solubility and potentially bioavailability of the drug was developed.

Hybrid Liquisolid Technique: A Novel Approach to Enhance the In-vitro Performance of Antidiabetic Drugs

Background: A combination of Glimepiride and Boswellia serrata extract reduces neuropathic diabetic complications by reducing the peroxidase level and improving the antioxidant level. The hybrid liquisolid method includes a combination of two methods, kneading and the liquisolid method, to enhance the drug’s in-vitro performance. Objective: The objective of this study was to enhance the in-vitro performance of antidiabetics drugs. Method: Tablets involving a fixed-dose combination of Glimepiride and Boswellia serrata extract were formulated by kneading method followed by liquisolid method. Screening of non-volatile solvents, carriers, and coating materials was carried out. The experiment was designed to optimize the formulation and the obtained model was validated concerning the design of the experiment. 3 level 2 factorial (32) design was applied by using Design expert software 11. Various pre-compression parameters were assessed to check the quality of the formulation. Results: Screening of excipients for kneading method, including Glimepiride with PVP K 30 (5%), and Boswellia serrata extract with Poloxamer 188 (13%), provided optimum drug release. For the liquisolid method, propylene glycol:PEG 400: Tween 80 (1:2:4) ratio for Glimepiride and PEG 400: Tween 80 (1:3) ratio for Boswellia serrata extract were selected. Common carrier and coating material for both drugs were selected to improve the in-vitro performance of the drug. Conclusion: This study enables an overall understanding of the impact of excipients on the quality of formulation, which may provide critical knowledge for the implementation of liquisolid systems.

Design of Experiments for Critical Material Attributes Assessment of Linagliptin and Metformin Fixed-dose Combination Tablets

Abstract: Aim of work: This study aimed to determine the amount of excipients in the critical material attributes of linagliptin and metformin sustained release (SR) fixed-dose combination (FDC) tablets using design of experiments (DoE). Methods: A 23 full factorial design with three center points was performed. For the screening of excipients, 3-factor responses (mannitol, sodium starch glycolate and pregelatinized starch for linagliptin; hydroxypropyl methylcellulose, sodium carboxymethyl cellulose (CMC) and hydroxypropyl cellulose for metformin), 2-levels and 1-center (n=3) point with three responses (friability, assay and dissolution) were applied to the DoE batch using Design-Expert. Results: Most excipients were an important factor in the friability, assay and dissolution results (P<0.05). In the screening of excipients, mannitol (40-60 mg) and pregelatinized starch (40-60 mg) with sodium starch glycolate (5 mg) for linagliptin and hydroxypropyl cellulose (15-23 mg) and CMC (40-55 mg) with hydroxypropyl methylcellulose (260 mg) for metformin were optimal. Conclusion: In summary, selection for the amount of excipients can be defined through levels of risk based on three responses. It can be concluded that the ranges of excipients leading to high quality (low friability and optimal ranges of assay and dissolution) for the screening of excipients were successfully observed by the DoE approach. Key words: Critical material attributes, Design of experiments, Linagliptin, Metformin, Quality by design.