Performance evaluation of presepsin using a Sysmex HISCL-5000 analyzer and determination of reference interval.

BACKGROUND: Analytical evaluation of newly developed presepsin by a Sysmex HISCL-5000 (Sysmex, Japan) automated immune analyzer was performed. METHODS: For evaluation, sepsis patient samples were collected before treatment in an emergency department. Precision, linearity, limit of blank/limit of detection, method comparisons, and reference intervals were evaluated. Method comparisons were performed using a PATHFAST immune analyzer (LSI Medience Corporation, Japan). RESULTS: Precision using a 20x2x2 protocol for low (306 pg/mL) and high (1031 pg/mL) levels resulted in within-laboratory standard deviation (95% confidence interval [CI]) and coefficient of variation (CV) %, which were as follows: 15.3 (13.1-18.7), 5.5% and 47.7, (40.5-58.1), 6.4%, respectively. Linearity using patient samples and calibrators were measured from 201 to 16,177 and 188 to 30,000 pg/mL, respectively. The regression equation was y = -23.2 + 1.008x (SE = 162.4) for low levels and y = 779.9 + 1.006x (SE = 668) for high levels. Method comparison by Passing-Bablock analysis was as follows: y = -209.77 + 1.047x (Syx  = 335.3). The correlation coefficient (95% CI) was 0.869 (0.772-0.927) with statistical significance (p < 0.001). Reference intervals from 120 normal healthy subjects showed that 300 pg/mL was the cut off. Presepsin tended to show a higher value at higher ages and in males. Presepsin showed correlation with some parameters, and the correlation coefficient (p value) were as follows: hematocrit, 0.198 (0.03); eGFR (CKD-EPI), -0.240 (0.0129); MDRD-eGFR, -0.194 (0.048), respectively. CONCLUSION: Presepsin measurement by HISCL-5000 showed reliable performance. Further clinical studies are required for the diagnosis and prognosis of sepsis.

The role of mass spectrometry and related techniques in the analysis of extractable and leachable chemicals.

In addition to degradation products, impurities, and exogenous contaminants, industries such as pharmaceutical, food, and others must concern themselves with leachables. These chemicals can derive from containers and closures or migrate from labels or secondary containers and packaging to make their way into products. Identification and quantification of extractables (potential leachables) and leachables, typically trace level analytes, is a regulatory expectation intended to ensure consumer safety and product fidelity. Mass spectrometry and related techniques have played a significant role in the analysis of extractables and leachables (E&L). This review provides an overview of how mass spectrometry is used for E&L studies, primarily in the context of the pharmaceutical industry. This review includes work flows, examples of how identification and quantification is done, and the importance of orthogonal data from several different detectors. E&L analyses are driven by the need for consumer safety. These studies are expected to expand in existing areas (e.g., food, textiles, toys, etc.) and into new, currently unregulated product areas. Thus, this topic is of interest to audiences beyond just the pharmaceutical and health care industries. Finally, the potential of universal detector approaches used in other areas is suggested as an opportunity to drive E&L research progress in this arguably understudied, under-published realm.

How sensitive does chemical characterization of medical devices need to be? Calibration of analytical evaluation thresholds with the carcinogenic potency database.

Chemical characterization is a component of the safety evaluation of medical devices. An analytical evaluation threshold (AET) is recommended to calculate the required analytical sensitivity. There is a lack of consensus whether to use 1.5 or 120 µg/day in calculating the AET with the lower value often requiring sensitivities beyond analytical capabilities. The Carcinogenic Potency Database (CPDB) was reviewed to compare risks associated with using either value to calculate an AET. The TD50s for non-Cohort of Concern (non-COC) substances in the CPDB were used to extrapolate the doses to an excess cancer risk of 10-5 and calculate the total doses. The number of non-COC substances that would exceed this risk using an AET calculated using 1.5 µg/day or 120 µg/day were then compared. From the 199 substances evaluated, only two posed an excess risk at an AET calculated with 1.5 µg/day and only seven more with 120 µg/day. Furthermore, over 95 percent of non-COC substances would not pose an excess cancer risk using an AET calculated with 120 µg/day. Based on our evaluation, an AET based on 120 µg/day is protective and practical for chemical characterization of short and long-term medical devices.

Analytical evaluation of four faecal immunochemistry tests for haemoglobin.

Objectives: Faecal immunochemical tests (FIT) for haemoglobin (Hb) are being used in the investigation of colorectal cancer. These tests use antibodies raised to the globin moiety of human Hb. Here, four automated quantitative FIT systems (HM-JACKarc, NS-Prime, OC-Sensor PLEDIA and SENTiFIT 270) are evaluated analytically to confirm whether the performance of the systems meet the manufacturers' claims. Methods: Assessment of the analytical performance of the FIT systems was undertaken using Hb lysates, real patient samples and external quality assessment (EQA) samples. This analytical assessment focused on detection characteristics, imprecision, linearity, prozone effect, recovery and carryover. Results: All four methods demonstrated good analytical performance, with acceptable within- and between-run imprecision, good recovery of f-Hb and limited carryover of samples. They also all show good linearity across the range of concentrations tested. The results of EQA samples showed different variations from the target values (-52 to 45%), due to the absence of standardisation across the different methods. Conclusions: All four systems are fit for purpose and have an analytical performance as documented by their manufacturers.

How to choose a point-of-care testing for troponin.

BACKGROUND: Point-of-care (POC) cTn assays are needed when the central laboratory is unable to provide timely results to the emergency department. Many POC devices are available. The prospect of choosing them is daunting. In order to provide a quick decision-making reference for POC cTn device selection comparing them to the central laboratory, seven POC devices commonly employed by emergency department were evaluated. METHODS: Firstly, we reviewed all devices package inserts. Secondly, we evaluated several POC cTn assays for imprecision, linearity, and correlation with central laboratory assays according to CLSI EP protocols. The linear regression analyses were performed only for the detectable concentrations. Five cTnI devices (Alere Triage, BioMerieux Vidas, Mitsubishi Pathfast, ReLIA TZ-301, and Radiometer AQT90) were evaluated against a contemporary cTnI assay (Beckman Access II Accu TnI). Two cTnT assays (Radiometer AQT90 and Roche Cobas h232) were compared to a high-sensitivity (hs) cTnT method (Roche Cobas e601). RESULTS: For cTn levels around the 99th percentile upper reference limits (URLs) of the comparator assays, imprecision could not be assessed for the Alere, BioMerieux, and Cobas h232 as they gave undetectable readings due to a lack of assay sensitivity. Imprecision (CV) was unacceptably high for the ReLIA (33.3%). On account of this precision metric, these four assays were deemed unsuitable. Regression analyses showed acceptable linearity for all the POC devices. The correlation coefficients for ReLIA, BioMerieux, Cobas h232, and Radiometer cTnT were >0.95. Unlike the cTnT devices, the cTnI assays employ different capture and detection antibodies leading to non-commutable results. The POC cTn results were concordant with their comparator-Radiometer cTnT 90%, Pathfast cTnI 85%, and Radiometer cTnI 75%. CONCLUSION: Our study provides the procedure and essential data to guide selection of a POC cTn device. Of the point-of-care devices, methods evaluated Radiometer AQT90 (cTnI and cTnT) and Pathfast might be considered.

Clinical and Analytical Evaluation of the Anyplex II HPV HR Detection Assay within the VALGENT-3 Framework.

In 2012, VALidation of human papillomavirus (HPV) GENotyping Tests (VALGENT) was initiated to provide a formalized and uniform study framework for comparison and validation of HPV assays with genotyping capability. In VALGENT-3, the clinical and analytical performance of Anyplex II HPV HR detection (Anyplex) was compared to that of the Hybrid Capture 2 HPV DNA test (hc2) and the cobas 4800 HPV test (cobas). The panel comprises 1,300 stored samples that were obtained from women 25 to 64 years old who participated in the Slovenian cancer screening program, enriched with 300 samples from women with abnormal cervical cytology. The sensitivity and specificity of Anyplex were noninferior to those of hc2, with a relative sensitivity of 1.01 (95% confidence interval [CI], 0.97 to 1.04) for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and 1.01 (95% CI, 0.97 to 1.06) for CIN3+ and relative specificity of 1.02 (95% CI, 1.00 to 1.03) for a CIN grade of ≤1. The clinical sensitivity of Anyplex for CIN2+ and CIN3+ was comparable to that of hc2 (P values for McNemar test [pMcN] of 0.655 and 0.564, respectively), but its specificity was significantly higher (pMcN = 0.008). The sensitivity and specificity of Anyplex were also noninferior to those of cobas, with relative sensitivity of 1.01 (95% CI, 0.98 to 1.04) for CIN2+ and 1.01 (95% CI, 0.99 to 1.04) for CIN3+ and relative specificity of 1.00 (95% CI, 0.99 to 1.01) (pMcN value of >0.05 in all cases). Regardless of the clinical outcome (CIN2+ or CIN3+), age restriction (women ≥30 years old), or comparator test used, Anyplex consistently showed excellent clinical performance and can be considered validated for primary cervical cancer screening.

Capillarys 2 Flex Piercing: Analytical performance assessment according to CLSI protocols for HbA1c quantification.

HbA1c is used for monitoring diabetic balance. In this paper we report an assessment of the analytical performances of Capillarys 2 Flex Piercing (C2FP) for HbA1c measurement using CE (Capillary Electrophoresis). CLSI (Clinical and Laboratory Standard Institute) protocols are used for the evaluation of apparatus performances: precision, linearity, method comparison, trueness and common interferences. HbA1c CVs average in intra-assay was 1.6% between run imprecision CV ranged from 0.1 to 1.8%. The linearity was demonstrated between 4.7 and 15.0%. The comparison study revealed that Bland Altman plot mean difference was equal to -0.03 (CI 95% (-0.05 to -0.0003)) and Passing-Bablok regression intercept was -0.05, CI95%(-0.13 -  -0.05); slope: 1.00, CI95%[1.00-1.01]. A strong correlation (r > 0.99) was proved. No significant effects of hemoglobin variants were seen with CE on HbA1c measurement. No problem related to sample-to-sample carry over was noted. No interferences of LA1c and cHb were observed. CE allowed quantification of HbA1c even at low level of total hemoglobin (40 g/L) in contrast to HPLC. Furthermore, this analyzer offered the opportunity of quantifying the HbA2 simultaneously with HbA1c . This evaluation showed that C2FP is a convenient system for the control of diabetes and the detection of hemoglobinopathies.

Challenges Associated with Biological Safety Assessments for Drug-Device Combination Products.

Biological safety assessments for drug-device combination products involve evaluation of the drug container closure and the device constituent part. When the device constituent part is the drug delivery system as well as the drug container closure system, both device and drug-based packaging standards have been deemed applicable. Approaches used for the biological safety assessment of medical devices differ from those used for pharmaceutical packaging/delivery systems. One area of difference is the extent to which chemical characterization with toxicological assessment is used either in addition to, or in place of, biological in vivo or in vitro tests. Differences also exist in the way nonclinical studies are used to evaluate the safety of medical devices or drug delivery systems. The lack of alignment in standards and guidance has resulted in confusion over what combination of tests and methods of evaluation constitute a biological safety assessment that will meet regulatory expectations for a drug-device combination product. The intent of this article is to discuss the challenges created when the packaging or delivery system is also a device constituent part of a drug-device combination product. Suggestions are offered regarding approaches that may be useful for conducting suitable biological safety assessments for drug-device combination products.

Evaluation of analytical and clinical performance of the AFIAS Tn-I plus assay - a new point-of-care.

BACKGROUND: The objective of this evaluation was to determine the analytical and clinical performance of the AFIAS point-of-care (POC) Tn-I Plus assay (Boditech Med Inc). DESIGN AND METHODS: Limit of detection (LOD), limit of quantification (LOQ), repeatability, reproducibility, inter- and intra-individual CV were evaluated using the CLSI guidelines. The study was also designed to estimate the 99th percentile upper reference limit (URL) and to assess the diagnostic sensitivity and specificity. RESULTS: The precision repeatability CVs were 6.7-8.5% and reproducibility was 7.5-7.6%. The LOD and LOQ were consistent with the manufacturer's specified values of 0.010 ng/mL and 0.030 ng/mL, respectively. The 99th percentile URLs for males (aged 18-75 years) and females (aged 17-65 years) in serum were 0.0300 ng/mL (7.8% CV) and 0.0239 ng/mL (9.4% CV) respectively. Overall 99th percentile URL was 0.0296 ng/mL (8.2% CV). For the overall apparently healthy population, the percentage of measurable cardiac troponin I (cTn-I) values below the 99th percentile (i.e. 0.0296 ng/mL) and above the assay's LOD (= 0.010 ng/mL) was 47,68% (391/820 samples). The diagnostic sensitivity and specificity were 100% with 95% CI (97% - 100%) and 95.2% with 95% CI (93.6% - 96.5%), respectively. No significant differences were observed for the diagnosis of acute myocardial infarction (AMI) between AFIAS Tn-I plus and Abbott ARCHITECT High Sensitive Troponin-I. CONCLUSION: The clinical performance of AFIAS Tn-I Plus assay for AMI is comparable to the established Abbott ALINITY STAT High Sensitive Troponin-I. This assay is suitable for routine use in clinical laboratories.

Extractive electrospray ionization mass spectrometry for analytical evaluation and synthetic preparation of pharmaceutical chemicals.

Extraction electrospray ionization mass spectrometry (EESI-MS), due to the unique configuration of its ionization module, enables the effective ionization of trace molecules of interest in samples containing complex matrices with high sensitivity, high selectivity and high responding speed without requiring sample pretreatment, and allows high-energy molecular species to undergo specially designed reactions for advanced functionalization. The typical effects of operating conditions on the analytical performance of extraction electrospray ionization mass spectrometry for various pharmaceutical compounds, pharmaceutical preparations and herbal materials were systematically reviewed. The application prospect of extraction electrospray ionization in molecular functionalization for advanced drug discovery is also briefly introduced.

Simultaneous determination of 13 nitrosamine impurities in biological medicines using salting-out liquid-liquid extraction coupled with liquid chromatography tandem mass spectrometry.

Nitrosamine impurities are being detected in various pharmaceutical products recently. However, no analytical method is provided for biopharmaceuticals. In present work, a salting-out liquid-liquid extraction (SALLE) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for quantification of thirteen nitrosamine contaminations in antibody drugs. The method showed excellent linearity over the range of 0.5-5.0 µg/L with LOQ (limit of quantitation) of 0.5 µg/L for targeted nitrosamines. The method was demonstrated to be accurate (recovery in a range of 75.4-114.7 %) and precise (RSD ≤ 13.2 %) for all nitrosamines using spiked samples. Especially, we found that the satisfactory recoveries for N-nitrosomethyl-4-aminobutyric acid (NMBA, 78.0-96.0 %) and 1-methyl-4-nitrosopiperazine (MeNP, 90.0-109.0 %) were just obtained in the opposite condition (with and without formic acid, respectively). In conclusion, we provide a sensitive and reliable method for nitrosamine estimations to ensure the safety of biological medications.

A Practical Derivation of the Uncertainty Factor Applied to Adjust the Extractables/Leachables Analytical Evaluation Threshold (AET) for Response Factor Variation.

The analytical evaluation threshold (AET) establishes which chromatographic peaks, produced during organic extractables/leachables (E&L) screening, require toxicological safety risk assessment because the peaks are associated with compounds of potentially unacceptable toxicity. Thus, the AET protects patient safety as its proper application ensures that all potentially unsafe E&L are necessarily assessed. Generally, application of the AET involves the presumption that all organic E&L have the same detector response factor, an assumption that is not valid for any of the detection methods commonly used in E&L screening. Thus, the AET's ability to be protective is compromised for poorly responding compounds, as they will appear to be below the AET when in fact they are not. This unacceptable outcome is addressed by adjusting the AET with an uncertainty factor (UF) whose value is dictated by the magnitude of response factor variation, with a larger variation resulting in a larger UF and a lower adjusted AET. Although the concept of the UF is straightforward, setting a generally accepted, scientifically valid, and practical value for the UF has been challenging. In this article, a database of relative response factors obtained for nearly 1200 E&L via the most commonly applied chromatographic screening methods (gas chromatography/mass spectrometry [GC/MS], liquid chromatography/mass spectrometry with atmospheric pressure chemical ionization [LC/MS-APCI], and LC/MS with electrospray ionization [LC/MS-ESI]) is used to justify UFs for these methods, individually and as a combined practice, based on the practical principle of "the point of diminishing returns". Using this concept results in nearly 92% of the compounds in the database being properly flagged as above an AET adjusted with a UF = 3. Ninety-five percent (95%) coverage of the compounds can be achieved when a UF of 4 is applied to the combination of GC/MS and LC/MS methods or with other combinations of UF values applied to the various methods individually. Coverage is increased to 97% when a UF of 4 is individually applied to the GC/MS method and a UF of 10 is individually applied to the LC/MS methods. Furthermore, the available data suggest that application of both APCI and ESI ionization in LC/MS screening (as opposed to either method separately) provides the greatest coverage of E&L.

Clinical irrelevance of lower titer thyroglobulin autoantibodies in patients with differentiated thyroid carcinoma.

Objective: Thyroglobulin (Tg) is an established tumor marker for differentiated thyroid carcinoma (DTC) patients. However, Tg immunoassays can be subject to Tg autoantibody (TgAb) interference resulting in incorrect Tg values. Therefore, Tg measurement with liquid chromatography-tandem mass spectrometry (LC-MS/MS) could be promising in patients with TgAbs. In this study, we compared Tg IRMA and Tg-LC-MS/MS analytically in the presence of TgAbs. Furthermore, we compared the clinical interpretation of results obtained by both Tg assays in DTC patients with lower TgAbs titers (<10 U/mL) during 131I ablation therapy. Methods: Totally 118 DTC patients diagnosed between 2006 and 2014 in a University Medical Center were followed with the Tg-IRMA (Thermo Fischer Scientific) and ARCHITECT anti-Tg (Abbott Laboratories) assays. We re-analyzed their samples with a sensitive Tg-LC-MS/MS method (Labcorp, limit of quantification of 0.02 ng/mL). Passing-Bablok regression analysis was performed on samples obtained during 131I ablation therapy and follow-up. Results: In 304 samples with lower TgAb titers, a good analytical agreement was found between both Tg assays (slope of 1.09 (95% CI: 1.05-1.16)). Fifty-five samples with potentially interfering TgAbs showed higher Tg-LC-MS/MS values than Tg-IRMA (slope of 1.45 (95% CI: 1.12->>100)). In patients(n = 91) with lower TgAb titers at the time of 131I ablation therapy, the Tg assays showed a clinical concordance of 91.2, 87.9, and 98.9%, respectively, using a Tg cut-off value of 1.0, 2.0, and 5.0 ng/mL. Conclusions: In DTC patients with lower titer TgAbs, Tg-IRMA is still a reliable and useful tumor marker. In DTC patients with potentially interfering TgAbs, Tg-IRMA values decreased due to TgAb interference.

Best Practices for Technical Reproducibility Assessment of Multiplex Immunofluorescence.

Multiplex immunofluorescence (mIF) tyramide signal amplification is a new and useful tool for the study of cancer that combines the staining of multiple markers in a single slide. Several technical requirements are important to performing high-quality staining and analysis and to obtaining high internal and external reproducibility of the results. This review manuscript aimed to describe the mIF panel workflow and discuss the challenges and solutions for ensuring that mIF panels have the highest reproducibility possible. Although this platform has shown high flexibility in cancer studies, it presents several challenges in pre-analytic, analytic, and post-analytic evaluation, as well as with external comparisons. Adequate antibody selection, antibody optimization and validation, panel design, staining optimization and validation, analysis strategies, and correct data generation are important for reproducibility and to minimize or identify possible issues during the mIF staining process that sometimes are not completely under our control, such as the tissue fixation process, storage, and cutting procedures.

The Implications of Chromatographically Screening Medical Products for Organic Leachables Down to the Analytical Evaluation Threshold Adjusted for Response Factor Variation.

A drug product is chromatographically screened for organic leachables, derived from the product's packaging system, as leachables might adversely impact the health of a patient to whom the drug product is administered. Similarly, medical device and packaging system extracts are chromatographically screened for organic extractables as probable leachables. To be protective of patient health, the screening methods must produce recognizable responses for all potentially unsafe substances. To be efficient, the screening methods should provide a means of differentiating between the responses linked to likely to be safe substances and to potentially unsafe substances. The analytical evaluation threshold (AET) was established as a means of differentiating chromatographic peaks, based on concentration, that are unlikely to be unsafe (and thus do not need safety assessment) and that are possibly unsafe (and thus require safety assessment). Thus, the AET manages the competing objectives of protection and efficiency. Although the AET is based on concentration, it is applied based on response. As no chromatographic detection method applied to extractables and leachables screening produces a uniform response to all potential analytes (thus, the magnitude of the response differs across analytes), the objectives of protection or efficiency can be compromised by false negatives and positives. To ensure protection at the expense of efficiency, the AET can be adjusted to address response variation. This article addresses the practical issue that the protectiveness of the AET is affected both by response factor bias and variation and thus correction for only variation is incomplete and ineffective. The article illustrates the proper adjustment of the AET for bias and variation.

An Analytical Strategy Based on Multiple Complementary and Orthogonal Chromatographic and Detection Methods (Multidetector Approach) to Effectively Manage the Analytical Evaluation Threshold (AET).

To address patient safety, a drug product is chromatographically screened for organic leachables. Similarly, medical device and packaging system extracts are chromatographically screened for organic extractables as probable leachables. To protect patient health, the screening methods must respond to all potentially unsafe substances. To be efficient, analytes determined to be below the toxicologically relevant threshold are removed from consideration before the subsequent analytical tasks of identification and quantitation are performed. The analytical evaluation threshold (AET) was established for use as a toxicologically relevant threshold to differentiate between chromatographic peaks that are unlikely to be unsafe (and thus do not need safety assessment) and those that are possibly unsafe (and thus require safety assessment). In practice, the instrumental response associated with the AET is determined using surrogate standards. It is then assumed that the response strength for an unknown extractable is equivalent to that for the surrogate standard at the AET concentration (i.e., relative response factor = 1). It is an unfortunate reality that response factors vary for different compounds on nearly all detector systems. This complicates the application of the AET and can result in a failure to include potentially toxicologically relevant compounds in the identification phase of the analysis. To ensure protection, an uncertainty factor was built into the AET equation that adjusts the AET downward to address response variation. Although this mechanism does increase the protectiveness of the AET, it assumes that the available methodology and instrumentation is sufficiently sensitive to reach the new lowered AET value. However, in some cases, the response variation is so great and the resulting uncertainty factor so large that the revised AET is below the achievable sensitivity specifications of even state-of-the art, expertly operated instrumental technologies. The only option then remaining is to concentrate the samples, which can result in adverse effects on analysis quality-counteracting the perceived benefit of lowering the AET. This article demonstrates how an analytical strategy based on methods with multiple complementary and orthogonal detection techniques (a multidetector approach) mitigates the problem of response factor variation and thus eliminates the need for large uncertainty factors and the resulting lower AET values. The primary concept is that all analytes only need to be effectively detected by at least one of the combination of detectors applied, and it is this effective technique (combination of all detectors and chromatographic methods utilized) that is used to perform the AET assessment.

Analytical Evaluation of the Ideal Strategy for High-Throughput Flow Injection Analysis by Tandem Mass Spectrometry in Routine Newborn Screening.

The introduction of tandem mass spectrometry (MS/MS) to clinical laboratories and the advent of expanded newborn screening (NBS) were crucial changes to public health programs worldwide. Speed, robustness, accuracy, selectivity, and specificity of analysis are all requirements of expanded NBS and are needed to minimize false positive results risks, to possibly eliminate false negatives, and to improve the positive predictive value of NBS. In this study, we firstly evaluated the analytical performances of the RenataDX Screening System, a fully integrated flow-injection MS/MS (FIA-MS/MS) IVD system for high-throughput dried blood spot (DBS) analysis in a routine NBS laboratory. Since a choice of several commercial NBS kits is available, we sought to compare NeoBaseTM 2 (PerkinElmer®) and MassChrom® (Chromsystems) non-derivatized kits on the RenataDX platform by evaluating their analytical performances. Moreover, we verified the degree of correlation between data obtained by the two different NBS MS/MS kits by FIA-MS/MS of over 500 samples. Our data suggest that both methods correlate well with clinically insignificant differences that do not impact the NBS result. Finally, while NeoBase™ 2 offers an easier and faster sample preparation, MassChrom® provides a cleaner sample extract which empirically should improve instrument reliability.

Evaluation of an unmanned aerial vehicle as a new method of pesticide application for almond crop protection.

BACKGROUND: Unmanned Aerial Vehicles (UAVs), a new method of application to deliver pesticides, is rapidly being adopted for commercial use in crop protection in East Asia with increasing worldwide interest. Pest control in mature almond orchards with dense foliar canopies presents greater coverage challenges than field crops and smaller orchard or vineyard crops. We investigated the use of an electric hexacopter to provide acceptable spray deposition and canopy penetration to be considered credible for use in an almond pest control program. RESULTS: The performance of the aerial and ground methods at different spray volumes were compared by analyzing spray deposition on water sensitive papers, insecticide residues on filter papers and residues on whole unhulled almonds at three canopy elevations. Overall residue levels of chlorantraniliprole insecticide on whole unhulled almonds across all pooled canopy strata were similar between UAV applied at 46.8 L/ha and 93.5 L/ha and the comparative air blast sprayer treatments applied at 935 L/ha. However, significant interactions between canopy elevation and spray method showed distinct residue patterns between the two application methods. Penetration and spray deposition at the lower canopy were observed and validated for the UAV application. Pest efficacy was evaluated by measuring nut damage at harvest. CONCLUSION: This study presents promising data that support the potential innovative integration of UAV's into crop protection programs for large canopy crops such as almonds and may guide future research for developing relevant label recommendations.

Correcting the Analytical Evaluation Threshold (AET) and Reported Extractable's Concentrations for Analytical Response Factor Uncertainty Associated with Chromatographic Screening for Extractables/Leachables.

It is generally acknowledged that quantitation in extractables and leachables (E&L) can be variably reproducible and accurate, depending on the quantitation approach taken. This is especially true for "simple" quantitation, which is the practice of estimating an analyte's concentration based on its response relative to that of an internal standard that has been added to the sample in a known amount. Simple quantitation is prone to error and variation as it is based on the largely false premise that the response factors for all extractables, leachables, and internal standard candidates are the same. It has been proposed that this uncertainty (inaccuracy and variation) be accounted for by adjusting two key parameters in E&L assessment, the reported concentrations themselves and the analytical evaluation threshold (AET) via an uncertainty factor (UF). This paper examines quantitation variation and discusses the means of establishing and utilizing the UF to adjust the AET to lower values and to adjust reported concentrations to higher values, enabling an impact assessment performed with this data to be more protective of patient safety. Although adjustment of the AET lower with the UF is supported, flaws in the concept of using the UF to adjust reported concentrations upward are considered, and it is recommended that the UF not be used in this manner. Rather, E&L quantitation should be based on compound-specific relative response factors, collected and collated in an E&L database.

Reducing relative response factor variation using a multidetector approach for extractables and leachables (E&L) analysis to mitigate the need for uncertainty factors.

Characterization of Extractables and Leachables (E&Ls) is an important aspect of product quality in important fields such as pharmaceuticals, medical devices and food contact materials. The main goal of an E&L study is identification and quantification of those species which may leach from packaging materials used to contain pharmaceuticals or which may leach directly out of a medical device or food contact material and thus may result in patient exposure. It is common practice to perform relative quantitation of extractables and leachables using surrogate standards due to the large diversity of species observed and the lack of available reference standards. A key problem in obtaining accurate E&L results arises due to response factor (RF) variation. Different compounds at the same concentration give different signal intensities and thus have different RF values. Two key aspects of study quality are affected by this problem. First, the evaluation of the number of compounds which are above the toxicologically relevant threshold (analytical evaluation threshold, (AET)) can be affected (RF Problem 1: AET Underreporting). Second, quantitative accuracy is affected which can reduce the reliability of the margin of safety (MOS) calculations which serves as the basis of the toxicological evaluation (RF Problem 2: Quantitative Error). RF databases have been the main solution proposed for solving these problems but do not reduce the underlying RF variation and lack the scope required to address quantitative error for compounds not contained in the database. In the absence of other solutions, large uncertainty factors (UF) have been applied in the AET calculations to account for RF Problem 1: AET Underreporting. These UF factors have been assigned values of 4 for GCMS and up to 10 for LCMS. Large uncertainty factors have a number of unintended negative consequences including the need for large amounts of sample concentration (>10X) prior to analysis resulting in potential compound loss or degradation and increased matrix effects. To overcome these problems, this publication demonstrates a multidetector approach using an HPLC system coupled with a Quadrupole Time of Flight Liquid Chromatography Mass Spectrometer (QTOF-LCMS), Charged Aerosol Detector (CAD) and an Ultraviolet-Visible Detector (UV) and a dual detection Gas Chromatography Mass Spectrometry (GCMS) system using a Polyarc Reactor system with Flame Ionization Detection (FID). Herein, it is demonstrated that this combination of methods (the multidetector approach) allowed detection and accurate surrogate standard quantitation of 217 unique extractables spanning a wide range of chemical properties (Mw, logP, pKa and boiling point). The combination of optimized detector selection with appropriate standard selection was verified to provide positive detection for 94% of the compounds at the AET level and a high level of quantitative accuracy (± 20% for 85% of the compounds and ±40% for 91% of the compounds) while using only a UF of 2. Unlike the RF database approach, the multidetector approach is not limited to only those compounds contained in the database but is applicable to the majority of extractables.