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Technical Review Article | Open Access | Published 2 July 2026
Analytical Methodology for Pharmaceutical Extractables and Leachables: A Comprehensive Approach for Containers and Closures
Sumeet Dwivedi¹*, Rajesh Kumar Chawla², Naresh Ambekar², Sweta S. Koka¹,Prerna Chaturvedi³ | EJPPS | 312 (2026) https://doi.org/10.37521/ejpps31208
Abstract
The control of extractables and leachables (E&L) from pharmaceutical packaging and delivery systems is paramount to ensuring patient safety and product quality. This manuscript provides a detailed, comprehensive analytical methodology for the identification, qualification, and quantification of E&L substances from containers and closures used across a wide range of pharmaceutical formulations, including oral liquids, nasal sprays, and injectables. The methodology is meticulously aligned with key international regulatory guidelines from bodies such as the International Council for Harmonisation (ICH), the U.S. Food and Drug Administration (FDA), and the United States Pharmacopeia (USP). The core framework encompasses a robust risk assessment, systematic controlled extraction studies, and the application of highly sensitive and orthogonal analytical techniques, including Gas Chromatography-Mass Spectrometry (GC-MS), Liquid Chromatography-Mass Spectrometry (LC-MS), and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). A critical component of the methodology involves the toxicological evaluation of identified compounds and the establishment of science-based acceptance thresholds, such as the Safety Concern Threshold (SCT) and the Qualification Threshold (QT). A detailed case study on a nasal spray formulation highlights the practical application of this methodology from initial sample preparation to data interpretation and regulatory submission. The manuscript also addresses common challenges faced during implementation, such as the analysis of low-level impurities and the absence of commercial reference standards and proposes practical solutions. Finally, it explores future perspectives for E&L analysis, including the integration of non-targeted screening and in silico toxicology.
Keywords: Extractables, Leachables, Pharmaceutical Packaging, Analytical Methodology, GC-MS, LC-MS, ICH, USP, FDA, Patient Safety, Qualification Threshold, Risk Assessment
Introduction
The primary packaging system for a pharmaceutical product serves as the first line of defense against physical damage, microbial ingress, and environmental degradation. However, the materials from which these systems are constructed—such as polymers, elastomers, and glass—are not inert. They can release chemical substances into the drug product over its shelf life, a phenomenon that poses significant risks to patient safety, product efficacy, and regulatory compliance. These impurities are broadly classified into extractables and leachables ¹,².
Extractables are compounds that can be forced from a material using aggressive solvents under exaggerated conditions of temperature and duration. They represent a "worst-case scenario" profile of all potential impurities that could migrate into the drug product ³. Leachables, on the other hand, are compounds that migrate from the packaging system into the drug product under normal storage conditions and are, therefore, a more direct measure of the actual risk to the patient.
The importance of E&L analysis is underscored by numerous regulatory guidelines. The U.S. FDA, European Medicines Agency (EMA), and ICH have issued comprehensive guidance ⁴,⁵, while the United States Pharmacopeia (USP) provides specific general chapters (e.g., <1663>, <1664>, <661.1>, and <661.2>) that define the requirements for E&L assessment ⁶,⁷. The primary objective of a robust E&L program is to identify and quantify these compounds and to ensure that they are present below a predefined, toxicologically acceptable level, a concept central to the Safety Concern Threshold (SCT) ⁸,⁹. This manuscript provides a detailed analytical methodology for the E&L analysis of pharmaceutical products, with a particular focus on the identification, calculation of acceptance thresholds, and a practical case study. The analytical strategy for assessing extractables and leachables (E&L) delineated in this manuscript has been formulated in accordance with the most recent internationally harmonized regulatory and pharmacopoeial standards. ISO 10993-18:2020 sets the rules for chemical characterization of extractables. It stresses the need for thorough chemical profiling, analytically justified worst-case extraction conditions, and linking analytical results to toxicological risk assessment.
The assessment of elemental impurities from container-closure systems and delivery devices adheres to the guidelines established in ICH Q3D(R2), taking into account route-specific permitted daily exposures (PDEs) and risk categorization based on patient safety. Validated inductively coupled plasma–mass spectrometry (ICP-MS) methods are used to carry out trace elemental analysis.
The development and validation of analytical methods for both targeted and non-targeted E&L studies adhere to the lifecycle approach outlined in ICH Q2(R2) and ICH Q14. This guarantees that analytical procedures are appropriate for their intended use, scientifically sound, and able to facilitate regulatory decision-making during product development and commercialization.
The methodology is also in line with current USP–NF standards, such as General Chapters <232> Elemental Impurities—Limits and Elemental Impurities—Procedures, which make sure that impurity control and analytical performance meet pharmacopeial standards.
METHODOLOGIES
A comprehensive E&L program is a structured, multi-phase process. It is a risk-based approach designed to efficiently identify and control potential impurities. The workflow can be broadly divided into four key stages: risk assessment, extractables study, leachables study, and toxicological evaluation.
The following sections provide a case study of an approach adopted in the evaluation of extractables and leachables.
Risk Assessment and Study Design
The extractables study design and chemical characterization strategy were aligned with ISO 10993-18:2020, emphasizing systematic identification, semi-quantification, and toxicological relevance of chemicals released from packaging materials under exaggerated conditions
A thorough risk assessment is the foundational step in any E&L program. It involves evaluating the potential for E&L based on:
Material of Construction: Certain materials, such as plastics, elastomers (rubber stoppers), and multi-layered packaging, are considered higher risk than glass.
Route of Administration: Injectables, nasal sprays, and inhalation products pose the highest risk due to direct contact with sensitive tissues.
Drug Product Formulation: The polarity and pH of the drug product can significantly influence the leaching process.
Storage Conditions: Higher temperatures and longer shelf lives increase the potential for leaching.
Based on this assessment, the scope and intensity of the subsequent analytical studies are determined. A high-risk scenario, such as a multi-dose nasal spray, would necessitate a more rigorous study than a low-risk scenario, such as a solid oral tablet in a blister pack.
Extractables Study: The "Worst-Case" Profile
The extractables study is designed to deliberately release the widest possible range of compounds from the packaging material.
Sample Preparation and Extraction Conditions
Packaging components are prepared by cutting them into small pieces to maximize the surface area-to-volume ratio. Extraction conditions were normalized using surface-area-to-volume (SA/V) ratios to ensure comparability across packaging components of different geometries. Packaging materials were extracted at an SA/V ratio of 6–20 cm²/mL under exaggerated conditions of 50–70°C for 72 h, consistent with ISO 10993-12 and USP <1663> recommendations. Extractions are performed using a range of solvents with varying polarities to simulate the drug product and to cover all potential extractables.
Aqueous solvents: Water for Injection (WFI), pH-buffered solutions.
Polar solvents: Ethanol, Isopropyl alcohol (IPA), or acetonitrile.
Non-polar solvents: Hexane, Toluene, or other hydrocarbons.
Solvent selection was based on polarity coverage to ensure representative extraction of potential leachables. Aqueous solvents simulated hydrophilic drug products, polar organic solvents targeted moderately polar additives and degradation products, while non-polar solvents facilitated extraction of hydrophobic antioxidants, plasticizers, and oligomers, in accordance with USP <1663>, <1664>, and ISO 10993-18:2020.
The extraction is carried out under elevated temperatures (e.g., 50-70°C) for an extended period (e.g., 72 hours). A negative control (blank solvent) is always prepared under identical conditions to identify any background impurities.
Procedural blanks consisting of extraction solvents subjected to identical time-temperature conditions were included with each extraction set to distinguish true material-derived extractables from background contaminants originating from solvents, laboratory ware, or analytical systems.
Analytical Techniques
The extracts are analyzed using complementary analytical techniques to ensure a comprehensive profile.
Gas Chromatography-Mass Spectrometry (GC-MS): This is the gold standard for volatile and semi-volatile organic compounds. GC provides excellent chromatographic separation, and MS provides a unique mass fragmentation pattern that can be used for identification.
Principle: The extract is injected into the GC, where compounds are vaporized and separated based on their boiling points and affinity for the stationary phase. The eluting compounds then enter the MS, where they are ionized, fragmented, and detected based on their mass-to-charge ratio (m/z).
Liquid Chromatography-Mass Spectrometry (LC-MS): This technique is essential for non-volatile, polar, and thermally labile compounds. High-resolution mass spectrometry (HRMS) is often coupled with LC to provide accurate mass and fragmentation data.
Principle: Compounds are separated on the LC column based on their interaction with the mobile and stationary phases. The eluting compounds are then ionized (e.g., Electrospray Ionization, ESI) and analyzed by a mass analyzer (e.g., TOF, Orbitrap), which provides highly accurate mass measurements.
Inductively Coupled Plasma-Mass Spectrometry (ICP-MS): We looked at elemental impurities that could come from packaging materials, elastomers, glass containers, and metal parts of devices. This was done according to ICH Q3D(R2) and USP–NF <232>/<233>. Risk assessment took into account the type of material used to build it, how it was given, the maximum daily dose (MDD), and how long the patient was exposed to it. Sample preparation and analysis were conducted utilizing ICP-MS, adhering to the requisite internal standards, system suitability criteria, and calibration methodologies as delineated in USP <233>. Results were articulated as daily patient exposure and juxtaposed with route-specific PDE values. Any elemental impurity surpassing the analytical evaluation threshold necessitated confirmatory analysis and toxicological assessment. ⁵.
System Suitability Testing:
Prior to analysis, system suitability tests were performed to verify instrument sensitivity, mass accuracy, chromatographic resolution, and signal stability. Acceptance criteria included consistent retention times, mass accuracy within ±5 ppm for HRMS, and response repeatability (%RSD ≤ 15%), in accordance with ICH Q2(R2).
Appropriate internal standards were incorporated into all analytical workflows to correct for variability arising from sample preparation, extraction efficiency, and instrumental response. Internal standards were selected based on chemical similarity and chromatographic behaviour relative to target analytes.
Non-Targeted HRMS Workflow for Extractables and Leachables
Data Acquisition Modes
Non-targeted high-resolution mass spectrometry (HRMS) analyses were performed using a combination of full-scan accurate-mass acquisition and data-dependent acquisition (DDA). Full-scan acquisition was conducted over a broad mass range to ensure comprehensive detection of unknown extractables and leachables, while DDA was employed to automatically trigger MS/MS fragmentation for features exceeding predefined intensity thresholds. Where applicable, data-independent acquisition (DIA) strategies were also considered to enhance MS/MS coverage of low-abundance features.
Feature Detection and Filtering
Raw HRMS data were processed using dedicated non-targeted data analysis software to extract molecular features based on accurate mass, retention time, and isotopic pattern. Feature filtering was applied to reduce analytical noise and false positives by excluding signals present in procedural blanks, background controls, or below predefined signal-to-noise thresholds. Only reproducible features detected consistently across replicate injections and relevant extraction conditions were retained for further evaluation.
Library Search and Identification Strategies
Tentative identification of retained features was performed using a tiered library-based approach. Accurate-mass measurements were matched against commercial and in-house spectral libraries (e.g., additive databases, polymer-related compound libraries, and publicly available MS/MS repositories). Isotopic pattern matching, predicted elemental composition, and fragmentation similarity scoring were used to refine candidate structures. Where available, retention time plausibility and known packaging material formulations were considered to support identification.
Confidence Levels for Identification
Compound identification confidence was assigned using a structured approach adapted from widely accepted HRMS identification frameworks. Level 1 identification required confirmation with an authentic reference standard based on matching retention time and MS/MS spectra. Level 2 identification corresponded to probable structure assignment supported by high-quality MS/MS spectral matching. Level 3 identification represented tentative candidate structures based on accurate mass and fragmentation patterns, while Level 4 denoted molecular formula assignment only. Features below Level 4 confidence were not reported unless toxicological relevance was suspected.
Reporting and Confirmation Thresholds
Only features exceeding the Analytical Evaluation Threshold (AET) were prioritized for reporting and identification. Compounds detected below the AET were documented but not subjected to full identification unless structural alerts or toxicological concerns were indicated. Features exceeding the AET required escalation to confirmatory analysis using targeted methods and, where feasible, reference standards. Quantitative confirmation was performed using validated targeted assays in accordance with ICH Q2(R2), and compounds exceeding qualification thresholds were subjected to formal toxicological risk assessment.
Leachables Study: The Real-World Profile
The leachables study is performed on the final drug product packaged in its intended container system. This study provides a direct measure of what compounds migrate into the product over time.
Study Design
The study is conducted under real-time (long-term) and accelerated storage conditions (e.g., 25°C/60% RH and 40°C/75% RH). Samples are analyzed at multiple time points, typically 0, 3, 6, 12, 24, and 36 months, to establish a leaching profile. The analytical methods used are the same as those in the extractables study but are validated for the specific drug product matrix.
Explanations, Calculation, and Acceptance thresholds
Compound Identification and Quantification
Once an analytical signal is obtained, the process of identification and quantification begins.
Tentative Identification: For GC-MS, identification is typically achieved by matching the mass spectrum of the unknown compound with a vast spectral library (e.g., NIST, Wiley). For LC-MS, accurate mass and isotopic pattern analysis are used to determine the molecular formula.
Confirmation: The identity of a compound is confirmed by comparing the retention time and mass spectrum with a certified reference standard.
Quantification: A calibration curve is generated using a series of known concentrations of the reference standard. If a reference standard is unavailable, a surrogate standard with a similar chemical structure and response factor can be used for semi-quantitative estimation.
Matrix Effect Mitigation
Matrix-induced ion suppression or enhancement was addressed using a combination of solid-phase extraction (SPE) clean-up, matrix-matched calibration, and the standard addition approach, depending on formulation complexity. These strategies ensured reliable quantification of leachables in complex pharmaceutical matrices in compliance with ICH Q2(R2) and USP <1225> principles.
Calculation of Acceptance Thresholds
The core of E&L risk assessment is the calculation of acceptance thresholds. The Safety Concern Threshold (SCT) is the level of daily exposure below which a leachable is considered to have a negligible safety risk [8]. The SCT values vary by route of administration:
Route of Administration | SCT (μg/day) ⁸,¹⁰ |
Injectables (Parenteral) | 0.15 |
Nasal Sprays | 5 |
Orally Inhaled | 0.15 |
Oral Liquids | 120 |
From the SCT, the Analytical Evaluation Threshold (AET) is calculated. The AET is a concentration level in the drug product:
AET (μg/mL) = SCT (μg/day) / MDD (mL/day), where MDD is the maximum daily dose of the drug product.
If a compound is detected at a concentration above the AET, it must be identified and quantified.
The Qualification Threshold (QT) is a higher threshold that, if exceeded, requires a formal toxicological qualification of the leachable, such as a review of existing toxicological data or a new safety study ¹¹.
Toxicological Evaluation
The final step is to assess the toxicological risk of the identified leachables. A toxicologist reviews the daily exposure level and compares it to the compound's Permitted Daily Exposure (PDE) or other established toxicological data ¹²⁻¹³.
Practical Applications and Case Study
Case Study: Nasal Spray with a Polypropylene Spray Pump
Background: A new nasal spray formulation, with a three-year shelf life, is being developed. The primary container is a glass bottle with a rubber stopper and a polypropylene (PP) spray pump with a metal spring. The risk is high due to the route of administration and the use of a plastic pump and elastomer stopper.
Extractables Study
Preparation: The PP pump and rubber stopper were extracted separately with water, 50% ethanol, and hexane at 60°C for 72 hours.
Analysis: GC-MS and LC-MS analysis of the extracts revealed several compounds. From the PP pump, BHT (Butylated Hydroxytoluene) and Irganox 1010 (an antioxidant) were identified. From the rubber stopper, a vulcanization accelerator, Zinc Diethyldithiocarbamate (ZDEC), was identified ¹⁴.
ICP-MS Extractables investigations were conducted in compliance with ISO 10993-18:2020, utilizing extraction conditions chosen to reflect analytically substantiated worst-case scenarios. Solvents of differing polarity were utilized for extraction, and extraction parameters were standardized using surface-area-to-volume ratios, temperature, and time in accordance with regulatory standards. Thorough chemical characterization was accomplished utilizing complementary analytical methods, such as GC-MS, LC-HRMS, and ICP-MS. Extractables identified were assessed for toxicological significance, and those surpassing defined analytical evaluation thresholds were prioritized for identification and risk assessment ¹⁵.
Leachables Study
Study Design: Compound Identification and Quantification
Analytical methods used for leachables quantification were validated in accordance with ICH Q2(R2), covering specificity, accuracy, precision, linearity, and limits of detection. Method development and ongoing performance verification followed the principles of ICH Q14 to ensure robustness and lifecycle management of analytical procedures ¹⁶⁻¹⁸.
The finished nasal spray product was stored at 25°C/60% RH (long-term) and 40°C/75% RH (accelerated). Samples were taken at 0, 3, 6, 12, 24, and 36 months.
Analysis: A validated LC-MS/MS method was used for Irganox 1010 and ZDEC, and a validated GC-MS method was used for BHT.
Findings (Hypothetical):
⮚ BHT concentration at 36 months (long-term): 0.05 μg/mL.
⮚ ZDEC concentration at 36 months (long-term): 0.008 μg/mL.
⮚ Irganox 1010 was not detected.
Toxicological Evaluation
MDD: The maximum daily dose for this nasal spray is 0.5 mL/day.
SCT for Nasal Sprays: 5 μg/day.
AET Calculation:
AET=5 μg/day/0.5 mL/day=10 μg/mL
Leachable Daily Exposure:
⮚ BHT: 0.05 μg/mL×0.5 mL/day=0.025 μg/day
⮚ ZDEC: 0.008 μg/mL×0.5 mL/day=0.004 μg/day
Comparison and Conclusion:
⮚ Both the BHT and ZDEC concentrations (0.05 μg/mL and 0.008 μg/mL, respectively) are well below the calculated AET of 10 μg/mL.
⮚ The daily exposure levels (0.025 μg/day and 0.004 μg/day) are also far below the SCT of 5 μg/day.
⮚ Based on these findings, the E&L from the nasal spray packaging do not pose a significant safety risk. This conclusion is documented and included in the stability section of the regulatory submission ¹⁹⁻²⁰.
The inclusion of normalized extraction parameters, analytical controls, system suitability criteria, internal standards, and matrix effect mitigation strategies enhances reproducibility, analytical robustness, and regulatory confidence in the proposed E&L methodology.
Challenges and Solutions in Implementation
Matrix Effects
The drug product matrix can suppress or enhance the analytical signal of leachables, leading to inaccurate quantification.
Solution: Use of matrix-matched calibration standards or the method of standard addition. Robust sample preparation techniques like solid-phase extraction (SPE) can also help isolate analytes from interfering compounds.
Lack of Reference Standards
Many E&L compounds, particularly degradation products or proprietary additives, lack commercially available reference standards. This makes accurate quantification difficult.
Solution: Employ a surrogate standard approach where a structurally similar compound with a known response factor is used. For identification, advanced mass spectrometry techniques such as HRMS with fragmentation analysis are critical for proposing a chemical structure and performing a toxicological assessment.
Non-Targeted Analysis
The number of potential leachables can be vast, making it impossible to create a targeted method for every single compound.
Solution: Use of non-targeted HRMS screening. This involves collecting comprehensive data on all detected ions, which can then be retrospectively analyzed against a database of known compounds or for unknown compounds using sophisticated data processing software.
Biologics and Combination Products
Biologic drug products and drug–device combination products present unique extractables and leachables (E&L) challenges due to their molecular complexity and sensitivity to low-level impurities. Common device-related leachables associated with biologics include silicone oil droplets, tungsten residues, and lubricants originating from syringes, cartridges, and delivery systems. Silicone oil, widely used as a lubricant in prefilled syringes, has been reported to induce protein aggregation, particle formation, and immunogenic responses through interfacial interactions. Tungsten residues, introduced during needle manufacturing, may catalyze protein oxidation or aggregation, particularly in monoclonal antibody formulations.
In addition, organic lubricants and processing aids can interact with proteins through hydrophobic or electrostatic interactions, potentially altering protein conformation and stability. Therefore, E&L assessment for biologics requires heightened sensitivity, orthogonal analytical approaches, and evaluation of both chemical and physical compatibility, consistent with USP <1663>, <1664>, and regulatory guidance for combination products ²¹⁻²².
Elastomers and Nitrosamine Risk
Elastomeric components such as rubber stoppers, seals, and plungers are recognized as high-risk sources of extractables due to the presence of curing agents, accelerators, antioxidants, and residual processing chemicals. Of particular regulatory concern is the formation and migration of nitrosamines, which may arise from secondary amines and nitrosating agents used in elastomer manufacturing.
Nitrosamine risk assessment in elastomeric closures requires targeted and non-targeted analytical strategies to detect both known nitrosamines and potential nitrosamine precursors. Analytical evaluation must consider low-level detection limits, worst-case extraction conditions, and toxicological thresholds aligned with ICH M7 principles. Consequently, elastomer E&L studies necessitate enhanced scrutiny, supplier material transparency, and robust risk-based justification to ensure patient safety ²³.
Parenteral Devices: Syringes and Cartridges
Parenteral drug products delivered via prefilled syringes, cartridges, and injection devices pose elevated E&L risk due to direct patient exposure and complex multi-material construction. These systems often comprise glass barrels, elastomeric plungers, silicone oil lubrication, metal needles, and polymeric components, each contributing potential extractables and leachables.
E&L evaluation for parenteral devices must account for cumulative exposure from multiple contact materials, prolonged contact time, and low permitted daily exposure limits. Particular emphasis is placed on particulate formation, elemental impurities, silicone oil migration, and interaction effects between device components and drug formulations. Accordingly, parenteral device assessments require stringent analytical sensitivity, comprehensive material characterization, and alignment with USP <1663>, <1664>, <232>/<233>, and applicable ISO standards ²⁴⁻²⁶.
Future Perspectives
The field of E&L analysis is continuously advancing with technological innovations and a growing understanding of drug-container interactions.
Integration of Data Science: The future of E&L analysis will heavily rely on data science and machine learning to analyze the massive datasets generated by HRMS. These tools can help identify patterns, predict leaching behavior, and link chemical structures to potential toxicological concerns ²⁷.
In Silico Toxicology: Computational models are being developed to predict the toxicity of E&L compounds based solely on their chemical structure. This can significantly reduce the need for costly and time-consuming in vivo and in vitro safety studies, especially for new or unknown leachables ²⁸.
E&L in Biologics: The focus is expanding to include biopharmaceutical products. The challenges are more complex due to the inherent sensitivity of proteins to impurities and the potential for leachables to cause aggregation or degradation of the active molecule ²⁹⁻³⁰.
Green Chemistry: There is a growing trend towards the use of more inert, sustainable, and less-leaching materials in pharmaceutical packaging to reduce the E&L burden from the outset.
Table 1. Safety Concern Threshold (SCT) by Route of Administration
Route of Administration | SCT (µg/day) | Toxicological Rationale | Regulatory Basis |
Parenteral (IV, IM, SC) | 1.5 | Highest systemic exposure; bypasses first-pass metabolism | USP <1664>, PQRI |
Ophthalmic | 1.5 | Direct tissue exposure, limited dilution | USP <1664> |
Inhalation | 1.5 | Rapid systemic absorption via lungs | PQRI OINDP |
Nasal | 5 | Partial mucosal absorption | PQRI |
Oral (solid/liquid) | 10 | First-pass metabolism reduces systemic burden | USP <1664> |
Topical / Dermal | 20–100* | Limited systemic absorption (product-dependent) | Risk-based assessment |
Note: Lower SCT applies to chronic use and vulnerable populations (pediatric, geriatric).
Table 2. Analytical Evaluation Threshold (AET) Calculation – General Equation
Parameter | Symbol | Description |
Safety Concern Threshold | SCT | Route-specific threshold (µg/day) |
Maximum Daily Dose | MDD | Maximum daily dose of drug product |
Extraction Dilution Factor | DF | Dilution during sample preparation |
Analytical Evaluation Threshold | AET | Reporting threshold for leachables |
AET Equation
Table 3. AET Calculation Examples Across Different Maximum Daily Doses (MDDs)
Assumptions: Route: Parenteral (SCT = 1.5 µg/day); Dilution Factor (DF) = 1
Product Type | MDD (mL/day) | AET (µg/mL) | Interpretation |
Low-dose injectable | 1 mL | 1.50 | Higher sensitivity required |
Moderate-dose injectable | 10 mL | 0.15 | Typical LC-MS detectability |
High-volume infusion | 100 mL | 0.015 | Requires HRMS |
Large-volume parenteral | 1000 mL | 0.0015 | Ultra-trace analysis needed |
Table 4. Technique-to-Analyte Mapping for E&L Studies
Analytical Technique | Primary Analytes | Typical Packaging Source |
GC-MS | Volatile & semi-volatile organics | Solvents, residual monomers |
GC-MS (HS) | Residual solvents | Elastomers, adhesives |
LC-MS | Non-volatile organics | Oligomers, antioxidants |
LC-HRMS (QTOF / Orbitrap) | Unknown extractables | Plastics, multilayer systems |
ICP-MS | Elemental impurities | Glass, metal components |
FT-IR | Polymer ID | Containers, closures |
NMR | Structural confirmation | Unknowns / leachables |
Table 5. Validation Parameters for E&L Analytical Methods
Parameter | Purpose | Typical Requirement |
Specificity | Distinguish analyte from matrix | No interference at AET |
Linearity | Quantitative accuracy | R² ≥ 0.99 |
Accuracy | Trueness of results | 80–120% recovery |
Precision | Repeatability | RSD ≤ 15% |
LOD | Detection capability | ≤ 30% of AET |
LOQ | Quantitation capability | ≤ AET |
Robustness | Method reliability | Minor changes acceptable |
Table 6. Acceptance Criteria for Extractables vs Leachables
Parameter | Extractables | Leachables |
Study Nature | Worst-case screening | Real-time assessment |
Acceptance Basis | Comparative profiling | SCT / AET |
Reporting Threshold | Technical threshold | AET |
Toxicological Review | Hazard identification | Mandatory |
Regulatory Impact | Informative | Decision-critical |
Table 7. Summary of a Comprehensive E&L Analytical Framework
Stage | Key Outcome |
Material characterization | Identify potential extractables |
Extractables profiling | Worst-case chemical space |
AET determination | Scientifically justified thresholds |
Leachables monitoring | Patient safety assurance |
Toxicological assessment | Regulatory acceptability |
Conclusion
The analytical methodology for pharmaceutical extractables and leachables is a critical component of product development and quality assurance. A comprehensive approach, starting with a robust risk assessment and leveraging a suite of modern analytical techniques, ensures that packaging systems do not compromise patient safety or product integrity. By adhering to international guidelines and applying sound scientific principles, companies can effectively identify and control E&L, ultimately securing regulatory approval and ensuring the safety of their products throughout their lifecycle. The systematic framework and practical case studies presented in this manuscript provide a clear roadmap for implementing a successful E&L program.
Acknowledgement
The authors express thanks to Brio Pharmaceuticals, Inc., Houston for support and providing the research facility to carry out the work.
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Author Information
Authors:
Sumeet Dwivedi¹*, Rajesh Kumar Chawla², Naresh Ambekar², Sweta S. Koka¹,Prerna Chaturvedi³
¹*Acropolis Institute of Pharmaceutical Education and Research, Indore, Madhya Pradesh, India
² Brio Pharmaceuticals Inc., 10863 Rockley Road, Houston, Texas, USA 77099
³ Chameli Devi Institute of Pharmacy, Indore, Madhya Pradesh, India
Corresponding Author: Sumeet Dwivedi
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