Biomek 3000: the workhorse in an automated accredited forensic genetic laboratory

We have implemented and validated automated protocols for a wide range of processes such as sample preparation, PCR setup, and capillary electrophoresis setup using small, simple, and inexpensive automated liquid handlers. The flexibility and ease of programming enable the Biomek 3000 to be used in many parts of the laboratory process in a modern forensic genetics laboratory with low to medium sample throughput. In conclusion, we demonstrated that sample processing for accredited forensic genetic DNA typing can be implemented on small automated liquid handlers, leading to the reduction of manual work as well as increased quality and throughput.     

A simple method for validation and verification of pipettes mounted on automated liquid handlers

We have implemented a simple, inexpensive, and fast procedure for validation and verification of the performance of pipettes mounted on automated liquid handlers (ALHs) as necessary for laboratories accredited under ISO 17025. A six- or seven-step serial dilution of OrangeG was prepared in quadruplicates in a flat-bottom 96-well microtiter plate, manually using calibrated pipettes. Each pipette of the liquid handler (1-8) dispensed a selected volume (1-200 μL) of OrangeG eight times into the wells of the microtiter plate. All wells contained a total of 200 μL liquid. The absorbance was read, and the dispensed volume of each pipette was calculated based on a plot of volume and absorbance of a known set of OrangeG dilutions. Finally, the percent inaccuracy (%d) and the imprecision (%CV) of each pipette were calculated. Using predefined acceptance criteria, each pipette was then either approved or failed. Failed pipettes were either repaired or the volume deviation was compensated for by applying a calibration curve in the liquid-handler software. We have implemented the procedure on a Sias Xantus, an MWGt TheONYX, four Tecan Freedom EVO, a Biomek NX Span-8, and four Biomek 3000 robots, and the methods are freely available. In conclusion, we have set up a simple, inexpensive, and fast solution for the continuous validation of ALHs used for accredited work according to the ISO 17025 standard. The method is easy to use for aqueous solutions but requires a spectrophotometer that can read microtiter plates.     

Automated genomic and proteomic applications on the Biomek NX laboratory automation workstation

This technical paper describes the utilization of a new automated liquid handler from Beckman Coulter, Inc., the Biomek^® NX Laboratory Automation Workstation, for genomic and proteomic applications. For genomic applications, methodology for plasmid DNA purification using Promega Wizard^® SV 96 reagents was developed for the Biomek NX. A single plate of bacterial pellets can be processed to purified plasmid DNA without user interaction after initial setup. DNA quantity and quality were assessed by spectrophotometric analysis, restriction digestion, PCR (The PCR process is covered by patents owned by Roche Molecular Systems, Inc., and F. Hoffman La Roche, Ltd.), and capillary sequencing. Additionally, the plasmid preparation method was used to purify plasmid DNA from bacterial clones isolated in a bacterial two-hybrid screening procedure. In this case, the system quickly and efficiently prepared clones for rapid identification of target sequences. For proteomic applications, His-tag proteins were purified from bacterial cultures in a 96-well plate format. Following purification, a Bradford assay was used to determine the quantitative yields of the His-tag protein products in each of the aliquots from the purified samples. The AD 340 Automated Labware Positioner (ALP), an integrated absorbance reader, was used for absorbance measurements in the Bradford assay. Given the placement of this ALP on the deck of the Biomek NX, the entire process of protein purification and quantitation was performed in a complete walk-away automated format. Results obtained when purifying proteins, from both uninduced and induced bacterial cultures, on the worksurface of the Biomek NX will be described.     

Automated selection of transcription factor binding sites

Double-stranded DNA binding sites that bound with high affinity to the nuclear factor kappa B (NFκB) p50 homodimer were selected using a Tecan Genesis workstation. The adaptation of the Tecan to automated selection required the integration of multiple devices and modifications to standard selection protocols, and resulted in a significant increase in throughput. The sequences obtained by automated selection strongly correlated with the well-known family of natural NFκB double-stranded DNA binding sites and with previous manual selection experiments. In addition, the selection experiments better defined the contributions of residues outside of the well-known, decameric core binding site for NFκB.     

Robotic nucleic acid isolation using a magnetic bead resin and an automated liquid handler for biological agent simulants

The events that occurred following the mailing of Bacillus anthracis-laced envelopes through the postal system has highlighted the need to perform biological screening on large numbers of environmental samples. High-throughput screening that relies on integrated robotic systems to speed analysis has been undertaken to handle the surge in samples requiring testing in events involving weapons of mass destruction. These automated screening systems require DNA extraction methods capable of handling environmental samples that contain inhibitors and have target organisms at low concentrations. This study describes the development of a method for the detection of the biological warfare agent simulants Erwinia herbicola and Bacillus subtilis var. niger spores using paramagnetic bead-based resin with an automated liquid handler and environmental samples.     

A user-friendly robotic sample preparation program for fully automated biological sample pipetting and dilution to benefit the regulated bioanalysis

Biological sample dilution is a rate-limiting step in bioanalytical sample preparation when the concentrations of samples are beyond standard curve ranges, especially when multiple dilution factors are needed in an analytical run. We have developed and validated a Microsoft Excel-based robotic sample preparation program (RSPP) that automatically transforms Watson worklist sample information (identification, sequence and dilution factor) to comma-separated value (CSV) files. The Freedom EVO liquid handler software imports and transforms the CSV files to executable worklists (.gwl files), allowing the robot to perform sample dilutions at variable dilution factors. The dynamic dilution range is 1- to 1000-fold and divided into three dilution steps: 1- to 10-, 11- to 100-, and 101- to 1000-fold. The whole process, including pipetting samples, diluting samples, and adding internal standard(s), is accomplished within 1 h for two racks of samples (96 samples/rack). This platform also supports online sample extraction (liquid-liquid extraction, solid-phase extraction, protein precipitation, etc.) using 96 multichannel arms. This fully automated and validated sample dilution and preparation process has been applied to several drug development programs. The results demonstrate that application of the RSPP for fully automated sample processing is efficient and rugged. The RSPP not only saved more than 50% of the time in sample pipetting and dilution but also reduced human errors. The generated bioanalytical data are accurate and precise; therefore, this application can be used in regulated bioanalysis.     

Automation of Serological Diagnosis for Herpes B Virus Infections Using Robot-Assisted Integrated Workstations

A robot-assisted automated facility was established within a biosafety level 3 laboratory located on a university campus. A unique integration of a Genesis (TECAN) liquid handler into the SAGIAN Core System (Beckman-Coulter) enabled tube liquid handling and transfer of reagents from tubes to microplates. An automated enzyme immunoassay (ELISA) for detecting herpes B virus antibodies was developed. Repetition experiments of the automated ELISA and comparison to the manual ELISA demonstrated the efficacy and high reproducibility of the automated method. It is anticipated that research and education activities will benefit from the establishment of the automated diagnostic laboratory in an academic environment.     

Collecting Sample Weight Data On Various Liquid Handling Robots

Liquid-handling platforms often do not provide a mechanism for collecting weight data needed for instrument qualification and sample transfer confirmation. This paper discusses the development, implementation, and application of a system that facilitates liquid-handling confirmation required for Good Laboratory Practice (GLP) compliance and provides an avenue to track the amount of sample transferred for extraction.The Balance Data Collector (BDC) system was designed as a flexible generic balance tool to be used with Tecan Gemini© and Packard WinPrep® software. The BDC system provides a user interface for balance configuration, a pointer to a file for storing weight data, and an external interface through command-line arguments. BDC is currently used for instrument qualification and sample collection in bioanalytical applications. Instrument qualification includes refining instrument liquid classes and verifying pipetting accuracy and precision. For bioanalytical applications using 96-well plates, BDC collects individual aliquot weights of samples transferred during an assay.The BDC system provides the user with the capability to control a balance via liquid-handling programming platforms such as Tecan Gemini© and Packard WinPrep®. Integration of liquid-handling platforms and BDC reduces the time the scientist must spend recording weight data needed for GLP compliance and can be used to increase accuracy of calculated sample concentrations.     

A completely automated sample preparation instrument and consumable device for isolation and purification of nucleic acids

Molecular diagnostic analysis and life science studies are dependent on the ability to effectively prepare samples for analysis. We report the development of a system that enables robust sample preparation of nucleic acids. To enable completely automated sample preparation, a consumable cartridge and consumable module system were developed to emulate every step of the sample preparation process. This included enzyme and reagent addition, temperature-controlled incubations, noncontact mixing of enzymes and reagents, buffer exchanges, and sample elution. Using this system, completely automated methods were developed for the purification of viral RNA and DNA from plasma and whole blood and of bacterial genomic DNA from water and whole blood. Extracted nucleic acids were detected and quantified using real-time PCR. The data indicate that automated viral DNA extraction was more efficient than sample extractions performed using a manual process, whereas automated total RNA extraction from the same samples was equivalent to controls. Additionally, we found that the process for bacterial genomic DNA extraction from either water or whole blood was equivalent to the manual extraction processes. We conclude the instrument, consumable cartridge, and reagent system enables easy, cost-effective, and robust sample preparation regardless of the experience of the operator.     

Extraction of genomic DNA and detection of single nucleotide polymorphism genotyping utilizing an integrated magnetic bead-based microfluidic platform

This study presents a new magnetic bead-based microfluidic platform, which integrates three major modules for rapid leukocytes purification, genomic DNA (gDNA) extraction and fast analysis of genetic gene. By utilizing microfluidic technologies and magnetic beads conjugated with CD_15/45 antibodies, leukocytes in a human whole blood sample can be first purified and concentrated, followed by extraction of gDNA utilizing surface-charge switchable, DNA-specific, magnetic beads in the lysis solution. Then, specific genes associated with genetic diseases can be amplified by an on-chip polymerase chain reaction (PCR) process automatically. The whole pretreatment process including the leukocytes purification and gDNA extraction can be performed in an automatic fashion with the incorporation of the built bio-separators consisting of microcoils array within less than 20 min. The detection of single nucleotide polymorphism (SNP) genotyping of methylenetetra-hydrofolate reductase (MTHFR) C677T region associated with an increased risk of genetic diseases was further performed to demonstrate the capability of the proposed system. The extracted gDNA can be transported into a micro PCR chamber for on-chip fast nucleic acid amplification of detection genes with minimum human intervention. Hence, the developed system may provide a powerful automated platform for pretreatment of human leukocytes, gDNA extraction and fast analysis of genetic gene.     

Purifying genomic DNA from whole blood on automated, high-throughput, and moderate-throughput platforms

We describe three new automated methods for purifying genomic DNA from whole blood. The MagneSil^® Blood Genomic, Max Yield System uses MagneSil^® paramagnetic particles (PMPs) in a 96-well format to purify the maximal amount of DNA from a 200-μL blood sample. In contrast, the MagneSil^® ONE, Fixed Yield Blood Genomic System uses MagneSil^® Fixed Yield PMPs to purify a normalized amount of DNA from 60 μL of blood in a 96-well format. These methods are implemented on the Beckman Coulter Biomek^® FX automated workstation. The MagneSil^® KF Genomic System uses MagneSil^® PMPs to purify DNA from 1 to 15 samples of 200-μL blood using the moderate-throughput Thermo Electron KingFisher^® mL instrument.The MagneSil^® Blood Genomic System typically yields > 4 μg per 200 μL of whole blood, depending on the white blood cell content. The MagneSil^® ONE System is best suited where there is a requirement for purification of a narrow concentration range of DNA. This system purifies 1 μg (±50%) of DNA from 60 μL of blood. The MagneSil^® KF System purifies 2 to 6 μg of DNA from 200 μL of blood. DNA purified using all of these methods is suitable for PCR, STR, READIT^® SNP genotype analysis, and multiplexed PCR analysis.     

A Study of a High-Throughput Plasmid DNA Purification System

An automated process that incorporates Millipore's Plasmid Miniprep₉₆ Montáge™ Kit with the Apogent Discoveries PlateMate Plus® and Tango™ automated high-throughput dispensing systems has been developed for purifying plasmid DNA. To test the efficacy of this process, parameters such as the reproducibility and consistency of the purified DNA quantity and quality as well as the purification speed were analyzed. The purification time for two plates of the Plasmid Miniprep₉₆ Kit (192 samples) was approximately 60 minutes using a PlateMate Plus equipped with 96 disposable tips and the Tango system equipped with 96 RB (resin bead) syringes. High uniformity and consistency in DNA yields (determined by spectrophotometric analysis) and quality (determined by gel electrophoresis analysis) among the different wells were observed. The purified plasmid DNA samples sequenced at an exceptional level with an average PHRED Q > 20 of 819 ± 25.*Millipore and Montage are the trademarks of Millipore Corporation     

Flexible, Parameter-Controlled Nanoliter Pipetting on a Tecan xyz Platform

Cost pressure and rising throughput requirements are important drivers for assay miniaturization. Typical examples for the trend “smaller is better” are found in BioChip applications and in High Throughput Screening (HTS), which is evolving from the 96-well standard to high-density microplates with 384, 864, 1536 or more wells. These applications require the automated pipetting of liquids in the submicroliter volume range, a difficult task for traditional automated liquid handling systems based on syringe pumps. Tecan developed a new device for the accurate pipetting of volumes in the nanoliter range. Based on ink-jet printer technology, this device allows the exact control of the volume of the ejected droplets via a set of parameters. The integration of this new technology into Tecan's flexible xyz-platforms allows an easy use of this powerful technology for several applications. Results such as volume range, accuracy and precision are discussed.     

A magnetic bead-based DNA extraction and purification microfluidic device

This article introduces a novel magnetic bead-based DNA extraction and purification device using active magnetic mixing approach. Mixing and separation steps are performed using functionalised superparamagnetic beads suspended in cell lysis buffer in a circular chamber that is sandwiched between two external magnetic coils. Non-uniform nature of magnetic field causes temporal and spatial distribution of beads within the chamber. This process efficiently mixes the lysis buffer and whole blood in order to extract DNA from target cells. Functionalized surface of the magnetic beads then attract the exposed DNA molecules. Finally, DNA-attached magnetic beads are attracted to the bottom of the chamber by activating the bottom magnetic coil. DNA molecules are extracted from magnetic beads by washing and re-suspension processes. In this study, a circular PMMA microchamber, 25 μL in volume, 500 μm in depth and 8 mm in diameter was fabricated to purify DNA from spiked bacterial cell cultures into the whole blood sample using Promega Magazorb DNA extraction kit. The lysis efficiency was evaluated using a panel of Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacterial cells cultures into the blood sample to achieve approximately 100,000 copy levels inside the chip. Manufacturer’s standard extraction protocol was modified to a more simplified process suitable for chip-based extraction. The lysis step was performed using 5 min incubation at 56 °C followed by 5 min incubation at room temperature for binding process. Temperature rise was generated and maintained by the same external magnetic coils used for active mixing. The yield/purity and recovery levels of the extracted DNA were evaluated using quantitative UV spectrophotometer and real-time PCR assay, respectively. Real-time PCR results indicated efficient chip-based bacterial DNA extraction using modified extraction protocol comparable to the standard bench-top extraction process.     

Web浏览器历史数据自动分类取证系统

为提高取证的自动化程度,提出了一种基于页面自动分类技术的浏览器历史数据取证算法,并设计实现了一个原型系统。该系统在获取浏览器历史数据的基础上,自动对其进行特征提取、页面分类。实验结果表明该系统有效提高了取证人员的效率和准确度。     

A Fully Automated High-throughput Nucleic Acid Purification System Using Silica Coated Magnetic Bead Technology

The design of a fully automated high-throughput system for the purification of sequencing templates is described. Hardware, software, and chemistries have been optimized to suit the needs of high-throughput laboratories involved in genome sequencing projects. Using this system, up to 5760 samples (60 x 96-well plates) can be purified in less than 16 hours during a single unattended run. The system can also be configured to perform sequencing reaction setup for all 60 plates following template purification, extending total run times to < 24 hours. Final sequencing reactions are prepared in 384- well microplates.     

Automated Lab-on-a-Chip Analysis of DNA Fragments

The design of a fully automated system for the analysis of DNA fragments in 96-well plates is described. Microfluidic technology is used to integrate sample loading, electrophoretic analysis, and fragment detection onto a miniature lab-on-a-chip device. The microfluidic chip operates in an instrument platform that automates sample access, data collection, and data reporting. Each microfluidic chip provides sizing and concentration values for more than 1000 DNA samples.     

Automatable Verification of Sequential Consistency

Sequential consistency is a multiprocessor memory model of both practical and theoretical importance. Designing and implementing a memory system that efficiently provides a given memory model is a challenging and error-prone task, so automated verification support would be invaluable. Unfortunately, the general problem of deciding whether a finite-state protocol implements sequential consistency is undecidable. In this paper we identify a restricted class of protocols for which verifying sequential consistency is decidable. The class includes all real sequentially consistent protocols that are known to us, and we argue why the class is likely to include all real sequentially consistent protocols. In principle, our method can be applied in a completely automated fashion for verification of all implemented protocols.     

The 104-well microplate

The 96-well microplate is a ubiquitous tool in the laboratory; its use is so extensive that in a limited number of situations it can be restrictive. Consider the situation where 96 samples need analysis or a downstream process in which the 96-well format leaves no space for additional standards or controls in the upstream 96-well processing. Consequently, plates are split or sample number reduced thereby incurring additional cost for plates, reagents, standards, controls, sample tracking, data files, and time to analyze the entire plate. A simple solution is proposed with the development of a companion 8 × 13-array microplate. The 104-well microplate was developed within the American National Standards Institute/Society for Biomolecular Science standards as to plate geometry and dimension, including well spacing (9 mm) with the exception that the columns have been shifted 4.5mm to the left to accommodate the 13th column. The extra column allows for additional standards/controls without modifying chemistry, incorporating additional plates or changing to a 384-well plate. We show negligible difference (-0.0003 optical density) when comparing mean absorbance readings in 96- and 104-well format. We demonstrate use of the 104-well plate in a 96-well environment by incorporating it in an enzyme-linked immunosorbent assay on a standard liquid handler. Results from the assay show no difference between formats (y=1.039x-0.004, r=0.997). Although the 104 plate was not created to supplant the 96-well standard, we conclude that the 104 plate can be incorporated into the 96-well environment without significant change in existing systems.