Validation of a DNA IQ™-based extraction method for TECAN robotic liquid handling workstations for processing casework

OctoShaker: A versatile robotic biomechanical agitator for cellular and organoid research

Mechanical forces have increasingly been recognized as a key regulator in the fate of cellular development and functionality. Different mechanical transduction methods, such as substrate stiffness and magnetic bead vibration, have been experimented with to understand the interaction between the biophysical cues and cellular outcome. In the exploration and utilization of the intrinsic cellular mechanism, bio-shakers, traditionally invented for stirring liquid, have garnered more interest as a tool to provide precise mechanical stimuli to aid in this study. Nonetheless, despite the usefulness of current bio-shaking technology, each type of shaker often offers a single mode of motion, insufficient for generating complex force dynamics needed to resemble the actual physical condition that occurs inside living organisms. In this study, we present OctoShaker, a robotic instrument capable of creating a multitude of motions that could be sequenced or programmed to mimic sophisticated hemodynamics in vivo. We demonstrated the programmed motion of circular convection and investigated its influence on micro-particle distribution in 96-well culture microplates. Biological samples, including HeLa cells and organoids, were tested, and unique resultant patterns were observed. We anticipate the open-source dissemination of OctoShaker in diverse biological applications, encompassing biomechanical studies for cellular and organoid research, as well as other disciplines that demand dynamic mechanical force generation.

Comparative analysis of two Rapid DNA technologies for the processing of blood and saliva-based samples

Rapid DNA technologies recently gained significant momentum as a means to generate DNA profiles faster than with standard laboratory workflows. Initially developed for the analysis of buccal reference samples, applications are being considered for other types of forensic samples. In this study, an identical set of 150 blood and saliva-based samples was processed using two different Rapid DNA technologies, the Applied BioSystems™ RapidHIT™ ID System using the RapidINTEL™ sample cartridge and the ANDE™ 6C Rapid DNA Analysis™ System using the I-Chip. A subset of samples were subjected to alternative collection methods or sample pre-treatments to determine the optimal strategy for each instrument. An equivalent sample set was also processed using a conventional DNA analysis workflow. The sensitivity range of the two Rapid DNA technologies was comparable based on blood and saliva dilution series, with both technologies able to generate full profiles from samples typically yielding 5-10 ng of DNA when processed using conventional DNA analysis. The brand of cotton swabs used for Rapid DNA analysis had an impact on the results for both systems. Differences were observed in success rate between the two systems when processing blood (on fabrics, FTA paper or hard surfaces) and saliva-based samples (drink containers, FTA paper, chewing gum, cigarette butt filter paper) and depended on the sample type. Importantly, deviating from the manufacturer's instructions for sample collection and pre-treatment was more detrimental to the ANDE 6C results. The quality of DNA profiles, as assessed using heterozygote peak height ratios, interloci balance and artifact presence, confirmed the results to be reliable and acceptable for single source samples. Profiling results were obtained when samples were reprocessed using the same Rapid DNA technology or conventional DNA analysis. Secondary analysis using a substitute software (GeneMapper ID-X v1.5) to recover additional genetic information was shown to be feasible. Finally, a comparison between the Applied Biosystems™ RapidHIT™ ID System Software v1.3.1 and v1.3.2 was also performed. Findings of this study could assist those interested in using Rapid DNA technology for blood or saliva-based samples, in various settings and for different applications.

Manual Silica-Based DNA Extractions

There are several silica-based extraction methods that utilize silica-packed columns or silica-coated paramagnetic resin and are suitable for the needs of forensic DNA analysis and/or human identification. These rely on the use of chaotropic salts to alter the affinity of DNA such that it binds strongly to silica. A variety of samples can be successfully processed with these procedures, including buccal swabs, dried or liquid blood, saliva, semen, and other typical forensic-type samples. This chapter will describe the manual extraction process for Promega's DNA™ IQ System, as well as Qiagen's QIAamp® DNA Blood Mini Kit, QIAamp® DNA Mini Kit, and QIAamp® DNA Investigator Kit.

Approaches to automation of the preanalytical phase of large-scale research in the biobank of the National Medical Research Center for Therapy and Preventive Medicine of the Ministry of Health of Russia

Aim. To create and validate an algorithm for automatic aliquoting of serum and plasma samples for biobanking as part of a large-scale study.

Material and methods. Biobank of the National Medical Research Center for Therapy and Preventive Medicine is equipped with a Tecan automated aliquoting system. When compiling the aliquoting program (script), the following parameters were selected: the time spent on spotting one complete cryobox, with a capacity of 96 cryotubes, the optimal number of vacutainers and tips for a single loading of the device. The program was created to receive 12 aliquots of 0,5 ml of blood serum, plasma with ethylenediaminetetraacetic acid and plasma with sodium citrate in cryotubes per 1 ml from eight participants in total from each in one cycle of device loading. Automatic and manual spotting was assessed in terms of the time spent on sample preparation and the quality of the aliquots obtained.

Results. A methodology for conducting the preanalytical phase of a  large-scale study based on the automation of biosample aliquoting has been developed and validated. We created scripts for aliquoting serum and blood plasma at the automated Tecan Freedom EVO system. An experiment conducted on biomaterial from 64 participants showed, that with an expected flow of 32 participants per day, it took more than 2 hours for manual aliquoting, and for automatic aliquoting (4 launches of the aliquot robot for 24 vacutainers from 8 participants) — less than 1,5 hours with the complete exclusion of human errors.

Conclusion. Automated aliquoting has a following number of advantages in comparison with manual: it allows to guarantee standardization and efficiency of sample preparation, reduce the time and increase the accuracy of aliquoting of biomaterial, save space in long-term storage freezers due to the use of smaller cryotubes. The developed algorithm for creating aliquoting programs and calculating the optimal use of consumables can be used in other projects.

Establishing an integrated pipeline for automatic and efficient detection of trace DNA encountered in forensic applications

The analysis of trace DNA is a crucial component in forensic applications. Biological materials containing low-level DNA collected at crime scenes, such as fingerprints, can be valuable as evidence. Automatic detection of biological samples has been largely embraced in forensic applications to meet the increasing throughput requirements. However, the amount of DNA automatically retrieved from trace evidence often tends to be small and unstable, ultimately resulting in poor detection of DNA profiles. Thus, in this work, we introduced a robust DNA extraction and purification platform named Bionewtech® BN3200 (Bionewtech®, Shanghai, China) with the goal of constructing a rapid automatic detection system for trace DNA. The establishment of automatic detection system for trace DNA mainly encompassed two parts: assessing the sensitivity of automatic extraction platform and screening the optimal short tandem repeat (STR) typing kit. The sensitivity of Bionewtech® BN3200 platform based on Ultra-sensitive DNA Extraction kit was initially estimated, demonstrating that this extraction platform might contain large potential in the trace DNA extraction. For the amplification part, three sets of commercial multiplex STR typing kits were selected as candidates, and the amplified products were further genotyped on the Applied Biosystems 3500xl Genetic Analyzer. After comparation, SiFa™ 23 Plex Kit was determined as the most suitable amplification system for trace DNA. Eventually, the newly exploited trace DNA detection system was successfully implemented in the detection of fingerprints derived from glass surfaces with the five-seconds contact time. As a result, the DNA recovered from the fingerprints fluctuated approximately from 57.60 pg to 18.05 ng, in addition, over 70% of the total STR loci were detected in 75% of the fingerprint samples.

Casework direct kit as an alternative extraction method to enhance touch DNA samples analysis

Latent fingerprints are commonly found in crime scenes, and currently used in forensic analysis to obtain STR profiles from DNA recovered from finger contact. Analysis of STR profiles obtained from touch DNA has been very useful to elucidate crimes and the extraction method may be determinant for the recovery of genetic material collected from different surfaces. This study aimed to verify and compare the efficiency of two different extraction kits for processing touch DNA samples obtained from fingerprints deposited on computer keyboards, knife handles and exterior door handles and steering wheels of cars. One hundred and four experiments were conducted to simulate crime scenes and evaluate the efficiency of two extraction kits for touch DNA samples: the DNA IQ™ System and the Casework Direct Kit (both Promega Corporation). Each experiment was conducted with two individuals in order to obtain a mixture profile. The genetic material deposited was collected by double swab method (Sweet et al. 1997) and DNA quantification was conducted using Quantifiler Trio™ (ThermoFisher Scientific). Samples were amplified by PowerPlex® Fusion System kit (Promega). It was possible to obtain STR profiles for 32 (61.5%) out of the 52 extracted using DNA IQ and 51 (98.1%) out of the 52 extracted using the Casework Direct Kit. Samples extracted by DNA IQ had higher average of quantification values for long targets (>200bp) across all tested surfaces. That seems to be due to an incompatibility between the Quantifiler Trio and the Casework Direct Kit. Samples with positive quantification but without STR profile, as well as samples without quantification but with STR profiles were also observed. Statistical analysis showed that the Casework Direct Kit produced significantly more useful profiles than DNA IQ (p-value = 0.001), since these profiles had more STR markers with allelic correspondence to second donators present in the mixture. This study provides insights about the effect of different surfaces and extraction methods on recovery and generation of STR profiles. Limitations for the quantification step for these samples with a low quantity of DNA were highlighted as well. We concluded that the Casework Direct Kit was much more efficient for processing touch DNA samples than DNA IQ.

An automated and compartmented fluidic reactor device for multi-step sample-to-answer processes using magnetic particles

A benchtop device that combines segmented flow with magnetic particle separation and active resuspension capabilities for biotechnological applications, e.g. biomolecule purification.

Rapid DNA analysis for automated processing and interpretation of low DNA content samples

Background

Short tandem repeat (STR) analysis of casework samples with low DNA content include those resulting from the transfer of epithelial cells from the skin to an object (e.g., cells on a water bottle, or brim of a cap), blood spatter stains, and small bone and tissue fragments. Low DNA content (LDC) samples are important in a wide range of settings, including disaster response teams to assist in victim identification and family reunification, military operations to identify friend or foe, criminal forensics to identify suspects and exonerate the innocent, and medical examiner and coroner offices to identify missing persons. Processing LDC samples requires experienced laboratory personnel, isolated workstations, and sophisticated equipment, requires transport time, and involves complex procedures. We present a rapid DNA analysis system designed specifically to generate STR profiles from LDC samples in field-forward settings by non-technical operators. By performing STR in the field, close to the site of collection, rapid DNA analysis has the potential to increase throughput and to provide actionable information in real time.

Results

A Low DNA Content BioChipSet (LDC BCS) was developed and manufactured by injection molding. It was designed to function in the fully integrated Accelerated Nuclear DNA Equipment (ANDE) instrument previously designed for analysis of buccal swab and other high DNA content samples (Investigative Genet. 4(1):1–15, 2013). The LDC BCS performs efficient DNA purification followed by microfluidic ultrafiltration of the purified DNA, maximizing the quantity of DNA available for subsequent amplification and electrophoretic separation and detection of amplified fragments. The system demonstrates accuracy, precision, resolution, signal strength, and peak height ratios appropriate for casework analysis.

Conclusions

The LDC rapid DNA analysis system is effective for the generation of STR profiles from a wide range of sample types. The technology broadens the range of sample types that can be processed and minimizes the time between sample collection, sample processing and analysis, and generation of actionable intelligence. The fully integrated Expert System is capable of interpreting a wide range or sample types and input DNA quantities, allowing samples to be processed and interpreted without a technical operator.

NucleoSpin(®) XS Columns for DNA Concentration and Clean-Up

The phenol-chloroform (organic) extraction method continues to be a preferred method for extraction of DNA from forensic evidence samples that may contain low quantities of DNA and polymerase chain reaction (PCR) inhibitors. The aqueous extracts from the organic extraction of DNA require subsequent concentration and cleanup, which has traditionally been performed with microdialysis filter units, including the Centricon(®) and Microcon(®) centrifugal filter devices. Here, we describe the use of the NucleoSpin(®) XS silica columns as an alternative for the concentration and purification of the aqueous extracts from the organic extraction and for the removal of PCR inhibitors from existing DNA extracts.

Developmental validation of a fully integrated sample-to-profile rapid human identification system for processing single-source reference buccal samples

Short tandem repeat (STR) DNA typing is a global standard for human identification. Current practice involves highly trained forensic analysts, operating in a laboratory setting, using multiple instruments to process samples and analyze the data. Here, we report the developmental validation of a fully integrated and automated DNA profiling system, the RapidHIT® System, capable of producing up to five high quality STR profiles with full controls in approximately 90min using PowerPlex®16 HS RapidHIT chemistry. The system integrates all sample handling steps: starting from lysis of cells on buccal swabs or other buccal sample types through DNA extraction, normalization, amplification,capillary array electrophoresis, detection, and integrated software analysis. The results describe the developmental validation of the RapidHIT™ System for buccal samples processed with the DNA IQ™ extraction chemistry using a guandinium chaotropic agent and paramagnetic beads followed by amplification using a modified version of PowerPlex 16 HS chemistry (PowerPlex 16 HS RapidHIT chemistry), and capillary electrophoresis with manual review of genotyping data following interpretation guidelines. All processing from the buccal swab to generation and processing of the profile occurs on the RapidHIT platform.

RESULT

are concordant with traditional methods, with 88% first pass success rates for both the CODIS and PowerPlex 16 loci. Average peak height ratios were 0.89 for buccal swabs. The system produces full profiles from swabs with at least 176 ng of saliva DNA. Rapid DNA identification systems will significantly enhance capabilities for forensic labs, intelligence, defense, law enforcement, refugee and immigration applications, and kinship analysis.

Elimination of bioweapons agents from forensic samples during extraction of human DNA

Collection of DNA for genetic profiling is a powerful means for the identification of individuals responsible for crimes and terrorist acts. Biologic hazards, such as bacteria, endospores, toxins, and viruses, could contaminate sites of terrorist activities and thus could be present in samples collected for profiling. The fate of these hazards during DNA isolation has not been thoroughly examined. Our goals were to determine whether the DNA extraction process used by the Royal Canadian Mounted Police eliminates or neutralizes these agents and if not, to establish methods that render samples safe without compromising the human DNA. Our results show that bacteria, viruses, and toxins were reduced to undetectable levels during DNA extraction, but endospores remained viable. Filtration of samples after DNA isolation eliminated viable spores from the samples but left DNA intact. We also demonstrated that contamination of samples with some bacteria, endospores, and toxins for longer than 1 h compromised the ability to complete genetic profiling.

Dual-force aggregation of magnetic particles enhances label-free quantification of DNA at the sub-single cell level

We recently reported the 'pinwheel effect' as the foundation for a DNA assay based on a DNA concentration-dependent aggregation of silica-coated magnetic beads in a rotating magnetic field (RMF). Using a rotating magnet that generated a 5 cm magnetic field that impinged on a circular array of 5mm microwells, aggregation was found to only be effective in a single well at the center of the field. As a result, when multiple samples needed to be analyzed, the single-plex (single well) analysis was tedious, time-consuming and labor-intensive, as each well needed to be exposed to the center of the RMF in a serial manner for consistent well-to-well aggregation. For more effective multiplexing (simultaneous aggregation in 12 wells), we used a circular array of microwells and incorporated 'agitation' as a second force that worked in concert with the RMF to provide effective multiplexed aggregation-based DNA quantitation. The dual-force aggregation (DFA) approach allows for effective simultaneous aggregation in multiple wells (12 demonstrated) of the multi-well microdevice, allowing for 12 samples to be interrogated for DNA content in 140 s, providing a ∼35-fold improvement in time compared to single-plex approach (80 min) and ∼4-fold improvement over conventional fluorospectrometric methods. Furthermore, the increased interaction between DNA and beads provided by DFA improved the limit of detection to 250 fg μL(-1). The correlation between the DFA results and those from a fluorospectrometer, demonstrate DFA as an inexpensive and rapid alternative to more conventional methods (fluorescent and spectrophotometric).

X chromosomal recombination--a family study analyzing 26 X-STR Loci in Chinese Han three-generation pedigrees

The aim of this study is to investigate genetic linkage and recombination fractions of 26 X chromosomal (X-STR) loci with two multiplex PCR systems (MX15-STR and MX12-STR). MX15-STR (including DXS7133, DXS6801, DXS981, DXS6809, DXS7424, DXS6789, DXS9898, DXS7132, GATA165B12, DXS101, DXS10075, DXS6800, GATA31E08, DXS10074, and DXS10079) and MX12-STR (including DXS6854, DXS9902, DXS6800, GATA172D05, DXS7423, HPRTB, DXS6807, DXS6803, DXS6804, DXS6799, DXS8378, and DXS8377) were successful analyzed on 206 two-generation families with two or more children and 33 three-generation families with 72 grandsons. Segregation analysis and calculation of recombination fractions between pairs of markers were performed. Linkage analysis of pairs of markers showed that there existed significant linkage (maximum LOD scores >2.0) within the physical distance of 48.5 Mb. Recombination events could be observed within the clusters of closed linked makers spanning <1.0 Mb. These results indicate that close cluster X-STRs used and recombination fractions of the selected loci will be very useful for biostatistical calculations in complex kinship analysis.

Development of a fast PCR protocol enabling rapid generation of AmpFℓSTR® Identifiler® profiles for genotyping of human DNA

Background

Traditional PCR methods for forensic STR genotyping require approximately 2.5 to 4 hours to complete, contributing a significant portion of the time required to process forensic DNA samples. The purpose of this study was to develop and validate a fast PCR protocol that enabled amplification of the 16 loci targeted by the AmpFℓSTR^® Identifiler^® primer set, allowing decreased cycling times.

Methods

Fast PCR conditions were achieved by substituting the traditional Taq polymerase for SpeedSTAR™ HS DNA polymerase which is designed for fast PCR, by upgrading to a thermal cycler with faster temperature ramping rates and by modifying cycling parameters (less time at each temperature) and adopting a two-step PCR approach.

Results

The total time required for the optimized protocol is 26 min. A total of 147 forensically relevant DNA samples were amplified using the fast PCR protocol for Identifiler. Heterozygote peak height ratios were not affected by fast PCR conditions, and full profiles were generated for single-source DNA amounts between 0.125 ng and 2.0 ng. Individual loci in profiles produced with the fast PCR protocol exhibited average n-4 stutter percentages ranging from 2.5 ± 0.9% (THO1) to 9.9 ± 2.7% (D2S1338). No increase in non-adenylation or other amplification artefacts was observed. Minor contributor alleles in two-person DNA mixtures were reliably discerned. Low level cross-reactivity (monomorphic peaks) was observed with some domestic animal DNA.

Conclusions

The fast PCR protocol presented offers a feasible alternative to current amplification methods and could aid in reducing the overall time in STR profile production or could be incorporated into a fast STR genotyping procedure for time-sensitive situations.

Competition for DNA binding sites using Promega DNA IQ™ paramagnetic beads

The Promega DNA IQ™ system is easily amenable to automation and has been an integral part of standard operating procedures for many forensic laboratories including those of the Royal Canadian Mounted Police (RCMP) since 2004. Due to some failure to extract DNA from samples that should have produced DNA using our validated automated DNA IQ™-based protocol, the competition for binding sites on the DNA IQ™ magnetic beads was more closely examined. Heme from heavily blooded samples interfered slightly with DNA binding. Increasing the concentration of Proteinase K during lysis of these samples did not enhance DNA recovery. However, diluting the sample lysate following lysis prior to DNA extraction overcame the reduction in DNA yield and preserved portions of the lysates for subsequent manual or automated extraction. Dye/chemicals from black denim lysates competed for binding sites on the DNA IQ™ beads and significantly reduced DNA recovery. Increasing the size or number of black denim cuttings during lysis had a direct adverse effect on DNA yield from various blood volumes. The dilution approach was successful on these samples and permitted the extraction of high DNA yields. Alternatively, shortening the incubation time for cell lysis to 30 min instead of the usual overnight at 56 °C prevented competition from black denim dye/chemicals and increased DNA yields.

Forensic trace DNA: a review

DNA analysis is frequently used to acquire information from biological material to aid enquiries associated with criminal offences, disaster victim identification and missing persons investigations. As the relevance and value of DNA profiling to forensic investigations has increased, so too has the desire to generate this information from smaller amounts of DNA. Trace DNA samples may be defined as any sample which falls below recommended thresholds at any stage of the analysis, from sample detection through to profile interpretation, and can not be defined by a precise picogram amount. Here we review aspects associated with the collection, DNA extraction, amplification, profiling and interpretation of trace DNA samples. Contamination and transfer issues are also briefly discussed within the context of trace DNA analysis. Whilst several methodological changes have facilitated profiling from trace samples in recent years it is also clear that many opportunities exist for further improvements.