Background

In time-sensitive forensic scenarios—such as the "72-hour golden window" of investigations, mass disaster victim identification, and emergency diagnostics—the speed of DNA profiling is a critical factor. Conventional STR amplification protocols often require 60 to 90 minutes, creating a bottleneck in rapid response workflows. To address this, we developed the NHID FaSTR 25A system, an ultra-rapid multiplex kit designed for accelerated human identification.

Methods and Design

The NHID FaSTR 25A kit features a proprietary blend of high-performance, thermostable hot-start DNA polymerase and an optimized reaction buffer. This formulation enables extreme PCR cycling parameters, targeting 23 STR loci (encompassing core CODIS markers) and two sex-determining loci. Key features include:

1. Accelerated Workflow: Achievement of complete amplification in just 27 minutes on standard thermal cyclers (e.g., ABI 9700), representing a 50% time reduction compared to industry-standard rapid kits.
2. Enhanced Platform Compatibility: Optimized for rapid detection platforms (such as CapitalBio), further reducing amplification time to approximately 20 minutes.
3. Direct Amplification: Fully compatible with direct PCR protocols for common forensic samples, including buccal swabs and bloodstain cards.

Results

Validation studies confirm that the system achieves high-speed processing without compromising data quality. The kit demonstrates robust performance across inhibited and degraded DNA templates, maintaining a high sensitivity threshold of 0.0625 ng. Furthermore, the system ensures seamless integration with standard capillary electrophoresis platforms (e.g., ABI 3500/SeqStudio), enabling an end-to-end "Sample-to-Profile" workflow within 60 minutes.

Conclusion

The NHID FaSTR 25A system establishes a new paradigm for rapid, high-throughput STR analysis. By significantly compressing the amplification timeframe while maintaining forensic-grade sensitivity and multiplexing capabilities, this system provides an essential technical platform for rapid human identification in challenging and time-critical environments.

Keywords

Forensic STR; Rapid PCR; NHID FaSTR 25A; Time-Sensitive Investigation; Human Identification; Direct Amplification

Authors

• Wanli Bi (NuHigh Biotechnologies Co.,Ltd., China)
• Zhifeng Wang (NuHigh Biotechnologies Co.,Ltd., China)
• Dongke Fu (NuHigh Biotechnologies Co.,Ltd., China)