Nanosimilars: A Scientific or A Regulatory Debate?

The paper highlights the necessity for a robust regulatory framework for assessing nanomedicines and their off-patent counterparts, termed as nanosimilar, which could be considered as 'similar' to the prototype nanomedicine,based on essential criteria describing the 'similarity'. The term 'similarity' should be focused on criteria that describe nanocarriers, encompassing their physicochemical, thermodynamic, morphological, and biological properties, including surface interactions and pharmacokinetics. Nanocarriers can be regarded as advanced self-assembled excipients (ASAEs) due to their complexity and chaotic behavior and should be evaluated by using essential criteria in order for off-patent nanomedicines be termed as nanosimilars, from a regulatory perspective. Collaboration between the pharmaceutical industry, regulatory bodies, and artificial intelligence (AI) startups is pivotal for the precise characterization and approval processes for nanomedicines and nanosimilars and embracing innovative tools and terminology facilitates the development of a sustainable regulatory framework, ensuring safety and efficacy. This crucial shift toward precision R&D practices addresses the complexity inherent in nanocarriers, paving the way for therapeutic advancements with economic benefits.

Regulations on excipients used in 3D printing of pediatric oral forms.

A promising solution to customize oral drug formulations for the pediatric population has been found in the use of 3D printing, in particular Fused Deposition Modeling (FDM) and Semi-Solid Extrusion (SSE). Although formulation development is currently limited to research studies, the rapid advances in 3D printing warn of the need for regulation. Indeed, even if the developed formulations include pharmaceutical excipients used to produce traditional oral forms such as tablets, the quantities of excipients used must be adapted to the process. Therefore, the aim of this literature review is to provide a synthesis of the available safety data on excipients mainly used in extrusion-based 3D printing for the pediatric population. A total of 39 relevant articles were identified through two scientific databases (PubMed and Science Direct). Then, groups of the main excipients were listed including their general information (name, chemical structure and pharmaceutical use) and a synthesis of the available safety data extracted from several databases. Finally, the role of the excipients in 3D printing, the amount used in formulations and the oral dose administered per form are presented.

Risks of dairy derived excipients in medications for lactose intolerant and cow milk protein allergic patients.

The use of lactose and cow milk protein (CMP) as potential allergens in pharmaceuticals and their ability to cause allergic reactions remains a significant concern in medicine. Lactose, a common pharmaceutical excipient due to its inert, inexpensive, and stable properties, is found in many prescription-only and over-the-counter medications. However, despite their widespread use, individuals with lactose intolerance (LI) or cow milk protein allergy (CMPA) may experience adverse reactions to these excipients. This study investigated the prevalence of lactose and other dairy-derived ingredients in pharmaceuticals marketed in Portugal. Using the Summary of Product Characteristics (SmPC) from the INFOMED database, various medications, including analgesics, antipyretics, non-steroidal anti-inflammatory drugs (NSAIDs), and antiasthmatics, were analyzed. Results showed a high prevalence of dairy-derived excipients, particularly in antiasthmatic drugs (62.6%) and NSAIDs (39%). Although CMP are not explicitly mentioned in SmPCs, the presence of lactose as an ingredient poses a risk of cross-contamination. The findings emphasize the need for healthcare professionals to be aware of potential allergens in medications and the importance of developing lactose-free alternatives to ensure the safety of patients with LI and CMPA. Further research is required to assess the safety and implications of lactose in medicines for these populations.

[Determination of fatty acid composition after saponification of common oil pharmaceutical excipients by supercritical fluid-evaporative light scattering method and its application in oil identification].

Oils and fats are commonly used in the pharmaceutical industry as solvents, emulsifiers, wetting agents, and dispersants, and are an important category of pharmaceutical excipients. Fatty acids with unique compositions are important components of oil pharmaceutical excipients. The Chinese Pharmacopoeia provides clear descriptions of the fatty acid types and limits suitable for individual oil pharmaceutical excipient. An unqualified fatty acid composition or content may indicate adulteration or deterioration. The fatty acid composition, as a key indicator for the identification and adulteration evaluation of oil pharmaceutical excipients, can directly affect the quality and safety of oil pharmaceutical excipients and preparations. Gas chromatography is the most widely used technique for fatty acid analysis, but it generally requires derivatization, which affects quantitative accuracy. Supercritical fluid chromatography (SFC), an environmentally friendly technique with excellent separation capability, offers an efficient method for detecting fatty acids without derivatization. Unlike other chromatographic methods, SFC does not use nonvolatile solvents (e. g., water) as the mobile phase, rendering it compatible with an evaporative light-scattering detector (ELSD) for enhanced detection sensitivity. However, the fatty acids in oil pharmaceutical excipients exist in the free and bound forms, and the low content of free fatty acids in these oil pharmaceutical excipients not only poses challenges for their detection but also complicates the determination of characteristic fatty acid compositions and contents. Moreover, the compositions and ratios of fatty acids are influenced by environmental factors, leading to interconversion between their two forms. In this context, saponification provides a simpler and faster alternative to derivatization. Saponification degrades oils and fats by utilizing the reaction between esters and an alkaline solution, ultimately releasing the corresponding fatty acids. Because this method is more cost effective than derivatization, it is a suitable pretreatment method for the detection of fatty acids in oil pharmaceutical excipients using the SFC-ELSD approach. In this study, we employed SFC-ELSD to simultaneously determine six fatty acids, namely, myristic acid, palmitic acid, stearic acid, arachidic acid, docosanoic acid, and lignoceric acid, in oil pharmaceutical excipients. Saponification of the oil pharmaceutical excipients using sodium hydroxide methanol solution effectively avoided the bias in the determination of fatty acid species and contents caused by the interconversion of fatty acids and esters. The separation of the six fatty acids was achieved within 12 min, with good linearity within their respective mass concentration ranges. The limits of detection and quantification were 5-10 mg/L and 10-25 mg/L, respectively, and the spiked recoveries were 80.93%-111.66%. The method proved to be sensitive, reproducible, and stable, adequately meeting requirements for the analysis of fatty acids in oil pharmaceutical excipients. Finally, the analytical method was successfully applied to the determination of six fatty acids in five types of oil pharmaceutical excipients, namely, corn oil, soybean oil, coconut oil, olive oil, and peanut oil. It can be combined with principal component analysis to accurately differentiate different types of oil pharmaceutical excipients, providing technical support for the rapid identification and quality control of oil pharmaceutical excipients. Thus, the proposed method may potentially be applied to the analysis of complex systems adulterated with oil pharmaceutical excipients.

Effects of Three Kinds of Carbohydrate Pharmaceutical Excipients-Fructose, Lactose and Arabic Gum on Intestinal Absorption of Gastrodin through Glucose Transport Pathway in Rats.

BACKGROUND: Some glucoside drugs can be transported via intestinal glucose transporters (IGTs), and the presence of carbohydrate excipients in pharmaceutical formulations may influence the absorption of them. This study, using gastrodin as probe drug, aimed to explore the effects of fructose, lactose, and arabic gum on intestinal drug absorption mediated by the glucose transport pathway. METHODS: The influence of fructose, lactose, and arabic gum on gastrodin absorption was assessed via pharmacokinetic experiments and single-pass intestinal perfusion. The expression of sodium-dependent glucose transporter 1 (SGLT1) and sodium-independent glucose transporter 2 (GLUT2) was quantified via RT‒qPCR and western blotting. Alterations in rat intestinal permeability were evaluated through H&E staining, RT‒qPCR, and immunohistochemistry. RESULTS: Fructose reduced the area under the curve (AUC) and peak concentration (Cmax) of gastrodin by 42.7% and 63.71%, respectively (P < 0.05), and decreased the effective permeability coefficient (Peff) in the duodenum and jejunum by 58.1% and 49.2%, respectively (P < 0.05). SGLT1 and GLUT2 expression and intestinal permeability remained unchanged. Lactose enhanced the AUC and Cmax of gastrodin by 31.5% and 65.8%, respectively (P < 0.05), and increased the Peff in the duodenum and jejunum by 33.7% and 26.1%, respectively (P < 0.05). SGLT1 and GLUT2 levels did not significantly differ, intestinal permeability increased. Arabic gum had no notable effect on pharmacokinetic parameters, SGLT1 or GLUT2 expression, or intestinal permeability. CONCLUSION: Fructose, lactose, and arabic gum differentially affect intestinal drug absorption through the glucose transport pathway. Fructose competitively inhibited drug absorption, while lactose may enhance absorption by increasing intestinal permeability. Arabic gum had no significant influence.

Mechanical Characterization of Vial Strain During Freezing and Thawing Operations Using Amorphous Excipients.

The purpose of this study was to investigate the mechanical stresses and strains acting on pharmaceutical glass tubing vials during freezing and thawing of model pharmaceutical formulations. Strain measurements were conducted inside of a laboratory-scale freeze-dryer using a custom wireless sensor. In both sucrose and trehalose formulations at concentrations between 5 % and 20 % w/v, the strain measurements initially increased before peaking in magnitude at temperatures close to the respective glass transition temperatures of the maximally freeze concentrated solutes, Tg'. We attribute this behavior to a shift in the mechanical properties of the frozen system from a purely elastic glass below Tg' to a viscoelastic rubber-like material above Tg'. That is, when the interstitial region becomes mechanically compliant at temperature above Tg'. The outputs were less predictable below 5 % w/v and tended to exhibit two separate peaks in strain output, one near the equilibrium melting temperature of pure ice and the other near Tg'. The peaks merged at concentrations between 4 and 5 % w/v where the largest strain magnitude was observed. The strain on primary packaging has traditionally been applied to evaluate the risk of damage or breakage due to, for example, crystallization of excipients. However, data collected during this study suggest there may be utility in formulation design or as a process analytical technology to minimize potentially destabilizing stresses and strains in the frozen formulation.

Facilitating direct compaction tableting of fine cohesive APIs using dry coated fine excipients: Effect of the excipient size and amount of coated silica.

The possibility of attaining direct compression (DC) tableting using silica coated fine particle sized excipients was examined for high drug loaded (DL) binary blends of APIs. Three APIs, very-cohesive micronized acetaminophen (mAPAP, 7 µm), cohesive acetaminophen (cAPAP, 23 µm), and easy-flowing ibuprofen (IBU, 53 µm), were selected. High DL (60 wt%) binary blends were prepared with different fine-milled MCC-based excipients (ranging 20- 37 µm) with or without A200 silica coating during milling. The blend flowability (flow function coefficient -FFC) and bulk density (BD) of the blends for all three APIs were significantly improved by 1 wt% A200 dry coated MCCs; reaching FFC of 4.28 from 2.14, 7.82 from 2.96, and > 10 from 5.57, for mAPAP, cAPAP, and IBU blends, respectively, compared to the uncoated MCC blends. No negative impact was observed on the tablet tensile strength (TS) by using dry coated MCCs despite lower surface energy of silica. Instead, the desired tablet TS levels were reached or exceeded, even above that for the blends with uncoated milled MCCs. The novelty here is that milled and silica coated fine MCCs could promote DC tableting for cAPAP and IBU blends at 60 wt% DL through adequate flowability and tensile strength, without having to dry coat the APIs. The effect of the silica amount was investigated, indicating lesser had a positive impact on TS, whereas the higher amount had a positive impact on flowability. Thus, the finer excipient size and silica amounts may be adjusted to potentially attain blend DC processability for high DL blends of fine APIs.

Pharmaceutical Compounding in Veterinary Medicine: Suspension of Itraconazole.

Itraconazole is a drug used in veterinary medicine for the treatment of different varieties of dermatophytosis at doses between 3-5 mg/kg/day in cats. Nevertheless, in Spain, it is only available in the market as a 52 mL suspension at 10 mg/mL. The lack of alternative formulations, which provide sufficient formulation to cover the treatment of large animals or allow the treatment of a group of them, can be overcome with compounding. For this purpose, it has to be considered that itraconazole is a weak base, class II compound, according to the Biopharmaceutics Classification System, that can precipitate when reaching the duodenum. The aim of this work is to develop alternative oral formulations of itraconazole for the treatment of dermatophytosis. Several oral compounds of itraconazole were prepared and compared, in terms of dissolution rate, permeability, and stability, in order to provide alternatives to the medicine commercialized. The most promising formulation contained hydroxypropyl methylcellulose and ß-cyclodextrin. This combination of excipients was capable of dissolving the same concentration as the reference product and delaying the precipitation of itraconazole upon leaving the stomach. Moreover, the intestinal permeability of itraconazole was increased more than two-fold.

Amelioration of tableting properties and dissolution rate of naproxen co-grinded with nicotinamide: preparation and characterization of co-grinded mixture.

OBJECTIVE AND SIGNIFICANCE: Reducing the dimensions, when other additives are present, shows potential as a method to improve the dissolution and solubility of biopharmaceutical classification system class II drugs that have poor solubility. In this investigation, the process involved grinding naproxen with nicotinamide with the aim of improving solubility and the rate of dissolution. METHODS: Naproxen was subjected to co-milling with urea, dimethylurea, and nicotinamide using a planetary ball mill for a duration of 90 min, maintaining a 1:1 molar ratio for the excipients (screening studies). The co-milled combinations, naproxen in its pure milled form, and a physical mixture were subjected to analysis using X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), and solubility assessment. The mixture displaying the highest solubility (naproxen-nicotinamide) was chosen for further investigation, involving testing for intrinsic dissolution rate (IDR) and Fourier-transform infrared spectroscopy (FTIR) after co-milling for both 90 and 480 min. RESULTS AND CONCLUSION: The co-milled combination, denoted as S-3b and consisting of the most substantial ratio of nicotinamide to naproxen at 1:3, subjected to 480 min of milling, exhibited a remarkable 45-fold increase in solubility and a 9-fold increase in IDR. XRPD analysis of the co-milled samples demonstrated no amorphization, while SEM images portrayed the aggregates of naproxen with nicotinamide. FTIR outcomes negate the presence of any chemical interactions between the components. The co-milled sample exhibiting the highest solubility and IDR was used to create a tablet, which was then subjected to comprehensive evaluation for standard attributes. The results revealed improved compressibility and dissolution properties.

Inconsistent excipient listings in DailyMed: implications for drug safety.

Excipients, or inactive ingredients, are a frequent cause of medication intolerance and allergy. Patients and clinicians concerned about medication allergies and sensitivities rely on the U.S. National Library of Medicine's DailyMed for accurate lists of excipients. Based on our anecdotal discovery of several examples of excipient omissions, we wished to examine the accuracy of DailyMed's listings more systematically in a sample of commonly prescribed medications. The objective of the study is to identify the frequency of inconsistency of excipient reporting within the DailyMed website. We performed a database audit of the Structured Product Labeling XML file provided by the drug manufacturer to the Food and Drug Administration and DailyMed for two randomly selected formulations of each of 50 commonly prescribed medications. For each of the 100 formulations, we compared the excipients listed in the "Description" to those in the "Ingredients and Appearance" sections in DailyMed. The Structured Product Labeling data file provided by the drug manufacturer contained internal inconsistencies of excipients in 39% of the formulations examined. Despite the use of Structured Product Labeling, the drug manufacturer's medication labels provided to the FDA and reported by DailyMed often contain conflicting information about inactive ingredients. Patients with allergies and excipient sensitivity should be aware of these discrepancies and consult multiple sections of the label to identify potential allergy-inducing inactive ingredients.

[Composite excipients for preparing concentrated water pills of personalized traditional Chinese medicine prescriptions by extruding-rounding method].

This study aims to optimize the composite excipients suitable for the preparation of concentrated water pills of personalized traditional Chinese medicine prescriptions by the extruding-rounding method and investigate the roles of each excipient in the preparation process. The fiber materials and powder materials were taken as the standard materials suitable as excipients in the preparation of personalized concentrated water pills without excipient. Water absorption properties and torque rheology were used as indicators for selecting the materials of composite excipients. The ratio of composite excipients was optimized by D-optimal mixture design. Moreover, to demonstrate the universal applicability of the optimal composite excipients, this study selected three traditional Chinese medicine prescriptions with low, medium, and high extraction rates to verify the optimal ratio. Finally, the effects of each selected excipient on the molding of personalized concentrated water pills were investigated with the four parameters of the pill molding quality as indicators. The optimized composite excipients were dextrin∶microcrystalline cellulose(MCC)∶low-substituted hydroxypropyl cellulose(L-HPC) at a ratio of 1∶2∶4. The composite excipients were used for the preparation of personalized concentrated water pills with stable process, good quality, and a wide range of application. Dextrin acted as a diluent and accelerated the speed of extruding. MCC mainly served as an adhesive, increasing the cohesion and viscosity of the pills. L-HPC as a water absorbent and disintegrating agent can absorb and hold the water of the concentrate and has a strong disintegration effect.

Understanding the Roles of Excipients in Moisture Management in Solid Dosage Forms.

Excipients are ubiquitous in pharmaceutical products, and often, they can also play a critical role in maintaining product quality. For a product containing a moisture-sensitive drug, moisture can be deleterious to the product stability during storage. Therefore, using excipients that interact with moisture in situ can potentially alleviate product stability issues. In this study, the interactive behavior of starch with moisture was augmented by coprocessing maize starch with sodium chloride (NaCl) or magnesium nitrate hexahydrate [Mg(NO3)2·6H2O] at different concentrations (5 and 10%, w/w). The effect of the formulation on drug stability was assessed through the degradation of acetylsalicylic acid, which was used as the model drug. The results showed that coprocessing of the starch with either NaCl or Mg(NO3)2·6H2O impacted the number of water molecule binding sites on the starch and how the sorbed moisture was distributed. The coprocessed excipients also resulted in lower drug degradation and lesser changes in tablet tensile strength during post-compaction storage. However, corresponding tablet formulations containing physical mixtures of starch and salts did not yield promising outcomes. This study demonstrated the advantageous concomitant use of common excipients by coprocessing to synergistically mitigate the adverse effects of moisture and promote product stability when formulating a moisture-sensitive drug. In addition, the findings could help to improve the understanding of moisture-excipient interactions and allow for the judicious choice of excipients when designing formulations containing moisture-sensitive drugs.

Lack of Effect of Antioxidants on Biopharmaceutics Classification System (BCS) Class III Drug Permeability.

The addition of antioxidants to pharmaceutical products is a potential approach to inhibit nitrosamine formation, particularly in solid oral dosage forms like tablets and capsules. The objective was to assess the effect of ten antioxidants on the permeability of four Biopharmaceutics Classification System (BCS) Class III drugs. Bi-directional drug permeability studies in the absence and presence of antioxidants were performed in vitro across MDCK-II monolayers. No antioxidant increased drug permeability, while the positive control sodium lauryl sulfate always increased drug permeability. Results support that any of the ten antioxidants, up to at least 10 mg, can be added to a solid oral dosage form without modulating passive drug intestinal permeability. Additional considerations are also discussed.

High throughput multidimensional liquid chromatography approach for online protein removal and characterization of polysorbates and poloxamer in monoclonal antibody formulations.

The majority of commercially available monoclonal antibody (mAb) formulations are stabilized with one of three non-ionic surfactants: polysorbate 20 (PS20), polysorbate 80 (PS80), or poloxamer 188 (P188). All three surfactants are susceptible to degradation, which can result in functionality loss and subsequent protein aggregation or free fatty acid particle formation. Consequently, quantitative, and qualitative analysis of surfactants is an integral part of formulation development, stability, and batch release testing. Due to the heterogeneous nature of both polysorbates and poloxamer, online isolation of all the compounds from the protein and other excipients that may disturb the subsequent liquid chromatography with charged aerosol detection (LC-CAD) analysis poses a challenge. Herein, we present an analytical method employing LC-CAD, utilizing a combination of anion and cation exchange columns to completely remove proteins online before infusing the isolated surfactant onto a reversed-phase column. The method allows high throughput analysis of polysorbates within 8 minutes and poloxamer 188 within 12 minutes, providing a separation of the surfactant species of polysorbates (unesterified species, lower esters, and higher esters) and poloxamer 188 (early eluters and main species). Accuracy and precision assessed according to the International Council for harmonisation (ICH) guideline were 96 - 109 % and ≤1 % relative standard deviation respectively for all three surfactants in samples containing up to 110 mg/mL mAb. Subsequently, the method was effectively applied to quantify polysorbate 20 and polysorbate 80 in nine commercial drug products with mAb concentration of up to 180 mg/mL.

Impact of Polyvinylpyrrolidone-Vinyl Acetate Copolymer and Sodium Starch Glycolate Excipients on Phenolic Extraction from Red Clover: Enhancing Biological Activity and Antioxidant Potential.

Adding certain excipients during the extraction process can enhance the concentration of target compounds, leading to potentially increased biological properties of the plant extract. This study explores the impact of PVP/VAC and SSG excipients on red clover bud extracts, aiming to enhance their concentration of target compounds and, consequently, their biological properties. The antioxidative potential was evaluated using DPPH, ABTS, and FRAP methods, and the chemical profile was determined using mass spectrometry. Antibacterial activity against various strains was determined through the minimal inhibitory concentration (MIC) method. The results revealed that the excipient-enriched samples exhibited significantly elevated antioxidant activities as well as phenolic and flavonoid contents compared to control samples. Notably, sample V1E3 demonstrated the highest antioxidant potential, with 52.48 ± 0.24 mg GAE/g dw (phenolic content), 463 ± 6.46 µg TE/g dw (ABTS), 12.81 ± 0.05 µg TE/g dw (DPPH), and 29.04 ± 1.16 mg TE/g dw (post-column ABTS). The highest flavonoid content was found in the S1E3 sample-24.25 ± 0.17 mg RU/g dw. Despite the increased antioxidant potential, no significant variance in antimicrobial activity was noted between the test samples and controls. This implies that excipients may hold the potential to enhance the biological properties of red clover extracts for pharmaceutical applications. These findings contribute valuable insights into optimizing extraction processes for improved functionality and application of plant-derived compounds in therapeutic formulations.

Exposure to potentially harmful excipients in medications among neonates at a state hospital in Malaysia.

OBJECTIVES: This study aimed to determine the incidence, types and predictors of Potentially Harmful Excipients (PHE) exposure among hospitalized neonates. METHODS: A prospective observational study was conducted from March to April 2022 in neonatal wards at a state hospital in Malaysia. The PHEs of interest were aspartame, benzalkonium chloride, benzyl alcohol, benzoic acid or benzoates, ethanol, parabens, polysorbate 80, propylene glycol, saccharin sodium, sorbitol and sulfites. Product information leaflets (PILs) and summaries of product characteristics (SPCs) were referred to obtain information on active pharmaceutical ingredient, strength, trade name as well as type and amount of the excipients. RESULTS: A total of 108 neonates were recruited and 97.2% of them were exposed to at least one PHE. Parabens (47.2%) and sulfites (27.5%) were the two most commonly administered PHEs. Benzyl alcohol is contraindicated in neonates but was administered to 8% of neonates in this study. The median daily dose of ethanol (24.11 mg/kg/day, IQR 19.73, 28.49) exceeded the acceptable daily intake (ADI) by four times. However, the dose was not available for all PHEs as this information is not always available in the PIL or SPC. Administration of cardiovascular drugs was associated with a higher risk of exposure to any PHE (OR 6.38, CI 2.75, 14.79, p-value < 0.001). CONCLUSION: The exposure of PHE among neonates in this study is high with certain PHEs exceeding the ADI. It highlights the need for certain strategies to be implemented to reduce such exposure in neonates.

Reexamining the diverse functions of arginine in biochemistry.

Arginine in a free-state and as part of peptides and proteins shows distinct tendency to form clusters. In free-form, it has been found useful in cryoprotection, as a drug excipient for both solid and liquid formulations, as an aggregation suppressor, and an eluent in protein chromatography. In many cases, the mechanisms by which arginine acts in all these applications is either debatable or at least continues to attract interest. It is quite possible that arginine clusters may be involved in many such applications. Furthermore, it is possible that such clusters are likely to behave as intrinsically disordered polypeptides. These considerations may help in understanding the roles of arginine in diverse applications and may even lead to better strategies for using arginine in different situations.

Near UV Photodegradation Mechanisms of Amino Acid Excipients: Formation of the Carbon Dioxide Radical Anion from Aspartate and Fe(III).

Carbon dioxide radical anion (•CO2-) is a powerful reducing agent that can reduce protein disulfide bonds and convert molecular oxygen to superoxide. Therefore, the generation of •CO2- can be detrimental to pharmaceutical formulations. Iron is among the most prevalent impurities in formulations, where Fe(III) chelates of histidine (His) can produce •CO2- upon exposure to near-UV light (Zhang and Schöneich, Eur. J. Pharm. Biopharm. 2023, 190, 231-241). Here, we monitor by spin-trapping in combination with electron paramagnetic resonance spectroscopy and/or high-performance liquid chromatography-mass spectrometry analysis the photochemical formation of •CO2- for a series of common amino acid excipients, including arginine (Arg), methionine (Met), proline (Pro), glutamic acid (Glu), glycine (Gly), aspartic acid (Asp), and lysine (Lys). Our results indicate that in the presence of Fe(III), Asp, and Glu produce significant yields of •CO2- under photoirradiation with near-UV light. Notably, Asp demonstrates the highest efficiency of •CO2- generation compared with that of the other amino acid excipients. Stable isotope labeling indicates that •CO2- exclusively originates from the α-carboxyl group of Asp. Mechanistic studies reveal two possible pathways for •CO2- formation, which involve either a ß-carboxyl radical or an amino radical cation intermediate.

The Past, Present, and Future of Oral Dosage Forms for Children.

The administration of medications to children has been a challenge for parents and caregivers for generations. Pharmaceutical companies have often overcome the difficulties of weight-based dosing and the -inability of most young children to swallow solid dosage forms by creating oral liquids. While oral liquids -offer advantages in terms of dose flexibility, swallowability, and ease of administration for young children and patients with enteral tubes, they have been plagued by issues such as taste, volume, and texture, to name a few. While the recommendations for broader use of oral syringes can help with the issue of measuring accuracy and incremental dosing, the issues of poor taste and frequently unacceptable volumes for doses remain a problem. New oral dosage forms which have begun to enter the United States marketplace have the potential to improve adherence and acceptability of oral medications for children, but come with their own unique challenges.