Bulk Formulations Research Articles

Evaluation of size-based distribution of components in VYXEOS® liposomal formulation using asymmetric flow field-flow fractionation

VYXEOS® is the first FDA-approved dual-API liposomal formulation containing two different chemotherapeutics, daunorubicin and cytarabine at a 1:5 molar ratio. Analysis of bulk formulation does not provide insight to size-based distribution of APIs and excipients, therefore asymmetrical flow field-flow fractionation (AF4) was utilized for the size-based separation of VYXEOS® liposomes and collected size fractions were further analyzed for the concentrations of APIs, lipid excipients, and copper. Analysis results revealed a significant variation in API distribution across the size fractions, with the larger liposomes encapsulating a higher ratio of cytarabine to daunorubicin compared to the smaller liposomes, while lipid excipient composition was held constant across the size range. We attribute the size-based variation of API ratios to structural change during API loading and sequence of API loading. Cytarabine is first passively loaded into liposomes containing copper gluconate, and then daunorubicin is actively loaded using copper gradient where the daunorubicin is retained in the liposomes as a copper complex. This method can be extended to characterize various single and dual-API liposomal nanocarriers during drug product development and/or post market quality control.

Evaluation of a weight‐based process for real‐time accurate confirmation of oral liquid controlled drug balances

AbstractTo meet legislative requirements in Australia, the balance of controlled drugs (CDs) must be confirmed after completion of each transaction. This is particularly challenging for liquid CD formulations, and over the years, health organisations have implemented various methods of performing this task, including the use of visual aids or conversion of bulk formulations to individual unit doses. These methods have a number of limitations. Therefore, this study aimed to evaluate the accuracy and feasibility of a weight‐based method for confirming oral liquid CD balances packed in multidose containers. This study was conducted in a palliative care ward of a metropolitan hospital over a 41‐day period. Morphine mixture 5 mg/1 mL transactions and balance checks were confirmed using weight calculations of the product bottle. The weights were then converted to volume using a locally developed electronic application, which was recorded in the relevant CD registers. The acceptable tolerance per transaction (±0.1 mL) was determined prior to commencement based on 80 test transactions. Throughout the trial period, 407 transactions were undertaken, among which there were no CD discrepancies. Nine nurses provided feedback via an anonymous online survey after the trial, mostly reporting that the new method was more accurate. However, participants also reported that it took on average 3 min longer to complete each transaction. In conclusion, utilising a weight‐based method of confirming liquid CD balances may present a feasible method of meeting legislative requirements related to the recording and accountability of CDs. This project was exempt due to the local policy requirements that constitute research by the Eastern Health Office of Research and Ethics (Reference no: QA24‐100‐111698). The justification for this ethics exemption was as follows: the study conformed with the National Health and Medical Research Council (NHMRC) Ethical considerations in quality assurance and evaluation activities and did not directly affect patient care; written consent was not required from participants per local requirements, however staff were provided verbal and written project information and were informed their participation in the survey was voluntary and anonymous.

Simplified Approximations of Direct Cumulus Entrainment and Detrainment

Abstract In recent years, direct calculations of simulated cumulus entrainment and detrainment have facilitated new physical insights into these highly elusive but critically important processes. However, these calculations require substantial computational resources that may limit their widespread usage. To facilitate such calculations, two simplified approximations of direct cumulus entrainment and detrainment are examined herein. The first approximation, termed the “semidirect” method, follows a standard bulk approach but makes more realistic assumptions about the sources of entrained and detrained air near the cloud edges. In contrast, the second approximation (the “projection” method) uses the governing equations of motion to project whether grid points near the cloud edge will entrain or detrain as the mean cloud ascends by one grid point. Verification exercises using large-eddy simulations reveal that both methods generally agree better with corresponding direct entrainment/detrainment estimates than the traditional bulk formulation, with the projection method outperforming the semidirect method. The two methods can be used in a synergistic fashion, with the semidirect method helping to optimize the projection method, to suit a wide range of applications. Because the latter incorporates the essential dynamics of entrainment and detrainment at the local scale, it can be used to gain physical insight into the causal mechanisms regulating these complex processes.

Solubility of Poorly Soluble Drugs in Phosphatidylcholine-Based Drug Delivery Systems: Comparison of the Loading Capacity in the Bulk Formulation and Its Dispersed State.

The aim of this study was to determine the drug loading capacity of phosphatidylcholine-based formulations for four poorly water-soluble drug substances (clofazimine, fenofibrate, artemether, cannabidiol). Two self-dispersing lipid formulations were investigated, which consisted of soybean phospholipids, medium-chain triglycerides and ethanol with a different phospholipid-oil ratio. The direct loading of the bulk formulation was conducted with dual centrifugation, which proved to be a suitable method for screening experiments with the highly viscous formulations. To estimate possible precipitation after dispersion in the gastrointestinal fluids, the solubility of the drugs was investigated in the dispersed formulations. For this purpose, nanodispersions were prepared from the bulk formulations via high pressure homogenization and subsequently subjected to passive loading. A newly developed HPLC method with Charged Aerosol Detection allowed a simultaneous evaluation of the content of soybean lecithin and medium-chain triglycerides in the nanodispersions. When comparing the two phosphatidylcholine-based formulations, a high content of oil was advantageous with regard to a high loading capacity. Drug substances with melting points below 150 °C exhibited a high solubility in the phospholipid-based formulations. A surprisingly high solubility was observed for artemether and cannabidiol with up to 13.0% and 33.3% drug loaded to the formulations, respectively. In the dispersions, a similar solubility as in the bulk formulations was obtained for fenofibrate and cannabidiol. Clofazimine yielded a higher loading result in the nanodispersions than in the bulk formulation.

UV Spectrophotometric Method for Estimation of Voriconazole in Bulk Form

This study presents a validated UV spectrophotometric method for the precise estimation of voriconazole in bulk formulations. Voriconazole, an essential antifungal agent, demands accurate quantification for its pharmaceutical applications. The proposed method leverages the sensitivity of UV spectroscopy to determine voriconazole concentrations effectively.
 The method's validation adheres to regulatory guidelines, ensuring reliability and accuracy. Spectrophotometric analysis was performed within a specific wavelength range, demonstrating linearity, precision, accuracy, and robustness across different concentrations of voriconazole.
 Parameters such as specificity, sensitivity, and stability were evaluated to affirm the method's suitability for routine analysis.
 The results indicate the method's efficacy in quantifying voriconazole in bulk and semi-solid forms with high precision and sensitivity. This validated UV spectrophotometric method presents a valuable tool for pharmaceutical analysis, facilitating quality control and assurance in voriconazole formulations.
 Keywords: Voriconazole, UV spectrophotometry, Anti-fungal, semi-solid formulation, Beer’s Lambert’s law.

A New Colorimetric Development and Validation of Visible Method for Estimation of Atorvastatin in Bulk Formulation

A simple, sensitive, accurate, precise and economical visible Spectrophotometric method was developed and validated for the estimation of Atorvastatin in Bulk form. The method is based on the reaction of Atorvastatin with MBTH Reagent [3-Methyl-2-Benzothiazolinone Hydrazone] in the presence of ferric chloride giving greenish blue colour chromogen which shows maximum absorbance at 566nm against reagent blank. The Chromogen obeyed Beer’s law in the concentration range of 5-25 µg/ml for Atorvastatin. The results of the analysis have been validated statistically and recovery studies confirmed the accuracy of the proposed method.

Group transfer polymerization in bulk methacrylates

AbstractGroup transfer polymerization (GTP) is a polymerization method developed to obtain targeted (meth)acrylic polymers in solution at ambient temperatures. In this work, it is employed with methacrylic monomers to obtain low Ð polymers in bulk. In this regard, different initiator systems that exhibit different mechanisms are compared concerning the molecular weight, the polydispersity and double bond conversion of the resulting bulk polymers. The respective systems were chosen carefully to give a broad overview of earlier developed initiator‐catalyst combinations 1‐methoxy‐1‐(trimethylsiloxy)‐2‐methylprop‐1‐ene (MTS) & tetrabutylammonium cyanide (TBACN) and more recently investigated initiating systems MTS & trityl tetrakis(pentafluorophenyl)borate (TTPB) or dimethyl phenyl silane (DMPS) & tris(pentafluorophenyl)borate (BCF). The described initiating systems are applied as a two‐component (2K) system to ensure a homogeneous distribution of the respective initiator and catalyst in the bulk monomer. In addition to the 2K experiments, photochemical initiation is also applied to bulk formulations. Therefore, a photoacid generator (PAG) and MTS is used to trigger the polymerization reaction by irradiation with UV light. A highly controlled photopolymerization method in bulk was developed that way achieving a low polydispersity polymer with high double bond conversion.

Physical characteristics and stability profile of recombinant plasmid DNA within a film matrix

Plasmids are essential source material for production of biological drugs, vaccines and vectors for gene therapy. They are commonly formulated as frozen solutions. Considering the cost associated with maintenance of cold chain conditions during storage and transport, there is a significant need for alternative methods for stabilization of plasmids at ambient temperature. The objective of these studies was to identify a film-based formulation that preserved transfection efficiency of plasmids at 25 °C. A model plasmid, pAAVlacZ, was used for these studies. Transfection efficiency and agarose gel electrophoresis were utilized to assess bioactivity and changes in physical conformation of plasmid during storage. An amino acid, capable of sustaining a positive charge while supporting an alkaline environment within the film matrix, preserved transfection efficiency for 9 months at 25 °C. Addition of sugar and a plasticizer to the formulation preserved the plasmid in an amorphous state and improved handling properties of the film. The manner in which excipients were incorporated into bulk formulations and environmental humidity in which films were stored significantly impacted transfection efficiency of plasmid in the rehydrated solution. Taken together, these results suggest that plasmids can be stored for extended periods of time without refrigeration within a film matrix.

In situ polymerization of sodium alginate and polyethylene glycol nano-formulations of acetamiprid against khapra beetle, Trogoderma granarium (Everts) (Coleoptera: Dermestidae)

Nano-formulations have been identified as a novel method of integrated pest management due to their increased effectiveness. Acetamiprid is an insecticide belonging to the group of neonicotinoids that selectively binds and interacts with the insect nicotinic acetylcholine receptor site, causing convulsions, paralysis, and ultimately death. Our research describes nano-formulated acetamiprid in situ polymerized using sodium alginate (AL) and polyethylene glycol (PEG). Third instar larvae of the Trogoderma granarium were sprayed using a potter tower for bioassays. LC50 for bulk formulation was 1.48 μg/cm2 and for AL and PEG were 0.85 μg/cm2 and 0.93 μg/cm2, respectively. Data analysis demonstrated that AL was 1.76-fold and PEG was 1.57-fold more toxic than bulk acetamiprid. LT50 for bulk formulation, AL, and PEG were 2104, 9, and 23 min, respectively. The results indicated that AL and PEG were more active and rapidly induced toxicity than bulk acetamiprid, viz., 224.18-fold and 92.58-fold, respectively. In vitro experiments revealed that protein, carbohydrate, glycogen, and lipid contents of treated larvae were significantly decreased. Detoxifying enzymes activities (glutathione S-transferases) were also reduced by AL and PEG-nano-encapsulated formulations but the activity of α-β-esterase were significantly increased. Based on outcomes, nano-formulation can enhance effectiveness of acetamiprid in terms of toxicity.

Development of an UV spectroscopic method for Capsaicin quantification in dosage form and in a bulk formulation

A proper procedure must be created to make sure that capsaicin, whether in dosage form or in bulk, can be identified. The method development makes sure that the amount of a capsaicin can be simply determined. To determine validation parameters like accuracy, precision, LOD, LOQ, recovery study and range for capsaicin. In the present study a proper UV Spectroscopic method was developed and validated for determination of capsaicin. UV Spectrophotometric method was done at 280nm and samples were prepared with Methanol. The linearity demonstrated a correlation coefficient of 0.9922 various validation parameters like accuracy, precision, LOD, LOQ, recovery study and range were found to be within the specified range. The proposed method was simple, rapid, precise, accurate and sensitive and can be used for routine analysis of capsaicin.

Method development and validation of nifedipine and lignocaine by RP-HPLC

For the validation of the nifedipine and lignocaine assay by reverse phase high performance liquid chromatography, in both pure form and tablet dosage form, a straightforward, quick, and exact approach has been established. ACN, Methanol, and perchloric acid were used as the mobile phase in chromatography on a Kromasil 100-5-C18 (4.6 x 150 mm, 5 m) column at a flow rate of 1.0 ml/min. 210 nm was used for detection. Nifedipine and lignocaine had retention times of 3.30 and 5.820.02 min, respectively. In the concentration range of 10–50 mg/ml of nifedipine and 20–100 mg/ml of lignocaine, the approach yields linear responses. The method precision for the assay result was less than 2.0%RSD, and the Nifedipine and lignocaine individual assays should be between 98% and 102.0%, respectively. The technique is helpful for pharmaceutical and bulk formulation quality control.

Developing and Validating the Quantification of Zanamivir in Bulk Formulations using UV-Visible Spectrophotometry

Developing and Validating the Quantification of Zanamivir in Bulk Formulations using UV-Visible Spectrophotometry

COMPARISON OF ACID DEGRADANT PRODUCT WITH METABOLIC PATHWAY OF REMOGLIFLOZIN ETABONATE IN DEVELOPED AND VALIDATED RP-HPTLC METHOD

Forced degradation studies in tablet and bulk formulations of remogliflozin etabonate have been developed using a precise and sensitive high performance thin layer chromatographic method. The silica gel RP-18 F254S plates were used as the stationary phase and ACN: water: ammonia solution (8:2:0.5 V/V/V) was used as the mobile phase for estimation. The proposed method was successfully validated, showing the Rf of the drug as 0.72 at 229 nm. The method was observed to be linear in the range of 500-3000 ng band-1 and then degradation was estimated by forced degradation pathway. In the forced degradation studies, the drug was found to be highly susceptible to both acid and base, including oxidative conditions, providing an active metabolite when remaining in contact in stressed conditions for a short time (30 min), while in longer duration (36 h), the drug provided another metabolite which on characterization was found to be inactive and predicted to be reported in the metabolic pathway

Mixing Pathways in Simple Box Models

Abstract Tracer variance budgets can be used to estimate bulk mixing in a control volume. For example, simple, analytical, bulk formulations of salt mixing, defined here as the destruction of salinity variance, can be found for estuaries with a riverine source of freshwater and a two-layer exchange flow at the mouth using salinity as a representative tracer. For a steady case, the bulk salt mixing M can be calculated as , where Sin and Sout are the representative salinities in the estuarine exchange flow, and QR and Qin are the river and landward volume fluxes, respectively. The bulk salt mixing M can be considered as the sum of mixing pathways, where each pathway has a mixing of Q(ΔS)2, where Q is the volume transport and ΔS is the salinity difference across the pathway. For the estuary case, one mixing path is associated with the river inflow, and the other is associated with the inflow of salty, oceanic water. This concept of linking mixing to input–output pathways is extended, in simple box models, from estuaries to scenarios with multiple inputs/outputs, as might be found in a complex estuarine/fjord network, in a region on a continental shelf, or any other control volume with multiple exchanges. This approach allows for the estimation of the relative contributions of each input–output pathway to the total mixing within a control volume.

Development and Validation of RP-HPLC Method for Quantification of Total, Free and Entrapped Ritonavir in Lipid Nanocarriers and Drug content of Film Coated Fixed Dose Formulation

Abstract: Aim: The current study was aimed to develop and validate a simple isocratic, precise, sensitive, accurate and robust reverse phase HPLC analytical method for the quantification of total, free and entrapped ritonavir in lipid nanocarriers and drug content of the film-coated fixed-dose formulation. Materials and Methods: The method was developed by using Inertsil ODS-3V C18 column as stationary phase, orthophosphoric acid (OPA) in water (pH 3.0) and acetonitrile as mobile phase. Further, the method was validated following ICH Q2(R1) guidelines. Ritonavir loaded lipid nanocarriers were developed using hot-emulsion and probe-sonication method. A solid phase extraction (SPE) method was developed for the separation of free and entrapped ritonavir. Total ritonavir was extracted from lipid nanocarriers (LNCs) and film-coated tablets using methanol and analyzed with validated method. Results: The responses were found to be linear and precise over a range of 0.25 μg/mL to 16 μg/mL. The limit of detection (LOD) and limit of quantification (LOQ) of the RP-HPLC method were found to be 14.06 ng/mL and 42.60 ng/mL, respectively which emphasizes the sensitivity of the method. The recovery of ritonavir from LNCs was found to be within 3% of the total drug present in LNCs. Similar, amount of drug recovery was found from assay of marketed formulation i.e., > 97%. Conclusion: The SPE method is capable of separating free and entrapped ritonavir from LNCs. The developed HPLC method is sensitive, robust, economical and gives high recovery. The developed HPLC method can also be employed for routine quantitative analysis of ritonavir in bulk formulation. Key words: HPLC method, Ritonavir, Validation, SPE, NLC, Bulk formulation.

A Validated Stability Indicating RP-HPLC Method for Simultaneous Determination of Lopinavir and Ritonavir in Bulk and Tablet Dosage Form

A rapid and precise reverse phase high performance liquid chromatographic method has been developed for the validated of Lopinavir and Ritonavir in its pure form as well as in tablet dosage form. Chromatography was carried out on a Kromasil C18 (4.6 x 250mm, 5µm) column using a mixture of TEA buffer (pH 4.0), Methanol in proportion 65:35 v/v as the mobile phase at a flow rate of 1.0ml/min, the detection was carried out at 227nm. The retention time of the Lopinavir and Ritonavir were found to be 2.079, 4.045 min respectively. The method produce linear responses in the concentration range of 5-35µg/ml for both Lopinavir and Ritonavir. The method precision for the determination of assay was below 2.0% RSD. The method is useful in the quality control of bulk and pharmaceutical formulations. The optimized method was validated and proved to be suitable for the quality control of the mentioned drugs in their different pharmaceutical dosage forms, according to ICH guidelines. The developed method was found to be fairly precise, rapid and economical for simultaneous estimation of Lopinavir and Ritonavir when compared with the reported method.

Method stability indicating method development and validation for emtricitabina by UV spectroscopic and RP-HPLC methods

Emtricitabine (commonly called FTC, systematic name 2 & 3’-dideoxy-5-fluoro-3-thiacytidine) is a nucleoside reverse-transcriptase inhibitor (NRTI) for the prevention and treatment of HIV infection in adults and children. The UV analysis of the drug was carried out on the 240nm wavelength. A simple, sensitive and accurate RP-HPLC method has been developed& validated for the determination of Emtricitabine in bulk formulation. Present method shows high sensitivity with linearity 10 to 50µg/ml (r2 = 0.9991). Various parameters according to ICH guidelines are followed for validating and testing of this method. Detection limit and quantitation limit were found to be 0.1534 µg ml and 0.4649 µgml respectively. The results demonstrated that the procedure is accurate, specific and reproducible and also being simple, cheap and less time consuming and appropriate for the determination of Emtricitabine in bulk formulation.

Stability-indicating RP-HPLC method development and validation for estimation of Mupirocin calcium in bulk and in pharmaceutical formulation

BackgroundA simple, rapid, sensitive and selective stability-indicating (RP-HPLC) method is suggested for the determination of Mupirocin calcium in bulk drug and in pharmaceutical formulation. Mupirocin calcium was eluted from a PrincetoneSPHER-100 C8 (250 × 4.6 mm, 5 µm) column with mobile phase consisting of methanol and water (75:25 v/v) pH adjusted to 4 with acetic acid. The gradient was optimized with a flow rate of 1 mL/min and a wavelength of 221 nm.ResultThe complete analytical method validation was successfully carried out as per ICH guidelines. The retrieval study was carried out at 80% to 120% level of working concentration, and results were in the range of 99 to 101%. The linearity was proven in range of 4–24 µg/mL of working concentration with linear regression curve (R2 = 0.999) with limits of detection (LOD) and quantitation (LOQ) being 0.35 and 1.08 µg/mL, respectively. The retention time for Mupirocin calcium was 5.09 min. The method shows good recoveries and intra-day and inter-day relative standard deviations were less than 2%. Validation parameters as ruggedness and robustness were also determined as per ICH guidelines and were found to be satisfactory. For stability study, the drug was exposed to various stress conditions such as acid, base, oxidation and sunlight as per recommendations of ICH guidelines.ConclusionThe developed HPLC method could be successfully used for the estimation of Mupirocin calcium in bulk and in Pharmaceutical formulation. The high recovery and low relative standard deviation confirm the suitability of proposed method that can be employed for the routine analysis in bulk and Pharmaceutical formulation.

The Vertical Structure and Entrainment of Subglacial Melt Water Plumes

AbstractBasal melting of marine‐terminating glaciers, through its impact on the forces that control the flow of the glaciers, is one of the major factors determining sea level rise in a world of global warming. Detailed quantitative understanding of dynamic and thermodynamic processes in melt‐water plumes underneath the ice‐ocean interface is essential for calculating the subglacial melt rate. The aim of this study is therefore to develop a numerical model of high spatial and process resolution to consistently reproduce the transports of heat and salt from the ambient water across the plume into the glacial ice. Based on boundary layer relations for momentum and tracers, stationary analytical solutions for the vertical structure of subglacial non‐rotational plumes are derived, including entrainment at the plume base. These solutions are used to develop and test convergent numerical formulations for the momentum and tracer fluxes across the ice‐ocean interface. After implementation of these formulations into a water‐column model coupled to a second‐moment turbulence closure model, simulations of a transient rotational subglacial plume are performed. The simulated entrainment rate of ambient water entering the plume at its base is compared to existing entrainment parameterizations based on bulk properties of the plume. A sensitivity study with variations of interfacial slope, interfacial roughness and ambient water temperature reveals substantial performance differences between these bulk formulations. An existing entrainment parameterization based on the Froude number and the Ekman number proves to have the highest predictive skill. Recalibration to subglacial plumes using a variable drag coefficient further improves its performance.

RP-HPLC method development and validation for the estimation of Sofalcone in bulk drug and formulations with forced degradation studies

RP-HPLC method development and validation for the estimation of Sofalcone in bulk drug and formulations with forced degradation studies