PCR 基因扩增仪（法医 DNA 分析系统）司法鉴定与刑事侦查合规应用介绍
作者：毕思特科技 来源：毕思特科技 浏览数：12 发布时间：2026/4/8 11:53:16
PCR 基因扩增仪（法医 DNA 分析系统）司法鉴定与刑事侦查合规应用介绍
【重要合规前置声明】本设备为法医 DNA 鉴定、司法鉴定专用核心实验室设备，仅面向具备法定法医物证鉴定资质的公安、检察、司法行政、司法鉴定等国家机关及授权鉴定机构定向研发、生产与销售，不向任何个人、无资质企业及非授权单位提供。本设备所有操作与应用，必须严格遵守《中华人民共和国刑事诉讼法》《中华人民共和国司法鉴定程序通则》《法庭科学 DNA 实验室规范》《法庭科学 DNA 检验规范》等国家法律法规与行业技术标准，必须在法定鉴定权限、授权检验范围内，由具备法医物证鉴定资质的专业人员规范操作，严禁任何无资质单位和个人违规开展 DNA 检验、侵犯公民个人遗传信息等违法违规行为。
产品概述
PCR 基因扩增仪（法医 DNA 分析系统），是一款基于聚合酶链式反应（PCR）核心原理打造的法医专用分子生物学核心设备，专为刑事案件现场提取的微量、严重降解、复杂基质的生物检材，进行 DNA 靶向片段的高效、特异性扩增深度定制。本设备通过高精度半导体温控系统，驱动耐热 DNA 聚合酶对特定基因序列进行指数级复制，可将检材中极微量的 DNA 模板扩增数十亿倍，为后续 STR 分型、DNA 序列分析、银染检测等司法鉴定环节提供充足、合格的检测靶标。
作为法医 DNA 检验全流程中的核心关键设备，其核心价值在于，能够从犯罪现场提取的极少量血迹、唾液斑、毛发、骨骼、牙齿、脱落上皮细胞等各类生物物证中，成功扩增出符合检验要求的 DNA 片段，获取可用于个体识别的完整 DNA 图谱，是解决刑事案件涉案人员同一认定、亲缘关系鉴定、未知名尸体身源查找、被拐人员身份确认等核心问题的关键技术支撑平台，也是各级公安刑事技术部门、司法鉴定机构法医 DNA 实验室的必备基础装备。
技术原理
本设备核心基于聚合酶链式反应（PCR）的核酸体外扩增原理工作，设备的温控精度、升降温速率、温度均匀性，是决定法医微量检材 DNA 扩增成功率、扩增特异性与结果重复性的核心关键，也是保障检验结果具备司法证据效力的科学基础。
设备通过高性能半导体热电温控模块，驱动 PCR 反应体系在三个关键温度节点之间，进行快速、精准、可重复的循环控温，完成 DNA 的指数级扩增：第一步为高温变性阶段，通过 94-95℃的高温环境，使双链 DNA 模板解链分离为单链，为引物结合提供模板；第二步为低温退火阶段，通过 50-65℃的精准温度控制，使特异性引物与单链 DNA 模板的目标序列精准互补结合，锁定扩增靶标；第三步为中温延伸阶段，通过 72℃的恒温环境，激活耐热 DNA 聚合酶的活性，使其以单链 DNA 为模板，沿引物方向合成新的 DNA 互补链，完成一次扩增循环。
每完成一次 “变性 - 退火 - 延伸” 的完整循环，目标 DNA 片段的数量理论上增加一倍，经过 25-40 次循环后，目标 DNA 片段可实现数十亿倍的指数级扩增，将原本无法检测的极微量 DNA 模板，放大至可进行 STR 分型、序列分析的检测水平。设备内置的智能控制系统，可对每一次循环的温度、时间、升降温速率进行精准闭环控制，确保所有反应孔内的扩增反应高度同步、均一，哪怕是严重降解、仅存 pg 级微量 DNA 的法医疑难检材，也能实现高效、特异性扩增，为后续司法鉴定提供稳定、可靠的扩增产物。
核心功能与合规实战价值
高精度快速半导体温控技术，保障疑难微量检材扩增成功率
设备采用行业领先的高性能半导体热电模块，可实现最高 4℃/ 秒的快速升降温速率，大幅缩短单次扩增循环时间，将传统数小时的扩增流程大幅压缩，显著提升法医实验室的案件检材处理效率。样品台温度均匀性≤±0.2℃，30-100℃范围内温度准确性≤±0.2℃，可确保 96 孔 / 25 孔反应体系内，所有反应孔的扩增环境高度一致，彻底避免了因温度不均导致的孔间扩增效率差异、非特异性扩增、扩增失败等问题，哪怕是现场提取的微量脱落细胞、陈旧骨骼、腐败组织等疑难降解检材，也能实现稳定、高效的特异性扩增，大幅提升疑难检材的 DNA 检验成功率，为案件侦破提供更多关键物证线索。
全场景灵活程序编辑能力，适配法医多元化遗传标记检测需求
设备具备极强的程序编辑灵活性，支持最多 40 个步骤的多级程序编辑，可实现 Touchdown PCR、Long PCR、多重嵌套 PCR 等多种高级扩增策略，完美适配法医 DNA 检验中多元化的检测需求。仪器内置存储空间可保存 120 组标准化扩增程序，同时支持通过 U 盘实现无限量程序下载与存储，便于实验室建立针对常染色体 STR、Y-STR、X-STR、线粒体 DNA 等不同遗传标记的标准化检验方法库，以及针对新鲜血斑、唾液斑、陈旧骨骼、微量脱落细胞等不同类型检材的专属扩增程序，实现一键调用、标准化操作，确保不同批次、不同类型检材的检验流程规范统一，完全符合司法鉴定机构的实验室认可与资质认定要求，保障检验结果的可重复性、可追溯性与司法有效性。
智能人性化防损设计，全方位保障珍贵法医检材安全
法医现场提取的生物检材多为微量、不可复现的珍贵物证，一旦损坏或污染将造成不可逆的证据灭失。设备针对法医检验场景做了专项优化设计，配备 5.7 英寸彩色液晶显示屏，可实时显示扩增温度曲线、程序进度与孔间温度状态，操作人员可全程监控扩增反应状态，及时处置异常情况。热盖采用高度无级可调、压力自适应设计，可完美兼容 0.2ml、0.5ml 各类规格的 PCR 单管与反应板，热盖温度支持 30-105℃宽范围可调，可确保管盖温度始终高于管内反应液温度，彻底杜绝反应液蒸发冷凝导致的体系浓度变化、扩增失败，避免珍贵检材的浪费。同时设备具备程序结束自动关闭热盖、4℃无限时样品保温、断电数据保护与程序恢复功能，哪怕是突发断电，也不会造成检材损坏与实验数据丢失，最大程度保障了法医珍贵检材的安全与实验流程的完整性。
高通量稳定运行设计，适配批量检材处理与 DNA 数据库建设
设备样品台兼容 0.2ml×25 孔与 0.5ml×25 孔双规格，兼顾了日常案件零星检材的快速检测与批量样本的高通量处理需求，整机采用工业级稳定设计，可支持 7×24 小时连续不间断运行，长期运行的温度精度、扩增稳定性无衰减，完美适配各级公安法医 DNA 实验室的案件检验、数据库建设双重需求。设备支持温度与时间的递增 / 递减功能，可满足法医实验室针对疑难检材的扩增条件优化、新遗传标记体系验证等科研需求，同时配备 USB2.0 与 RS232 双通讯接口，可实现扩增程序、实验数据的批量导出与溯源管理，契合法医 DNA 实验室的全流程信息化、规范化管理要求，为法医 DNA 数据库建设提供标准化、高质量的 DNA 扩增产物，支撑数据库的海量数据积累与跨区域串并案比对应用。
全流程可追溯管理，契合司法鉴定合规性核心要求
设备所有扩增程序、运行参数、温度曲线、实验时间等核心数据，均可完整记录、导出与存档，可与法医 DNA 实验室的 LIMS 实验室信息管理系统无缝对接，实现从检材受理、DNA 提取、扩增、分型到报告出具的全流程可追溯、可复核，完全符合《司法鉴定程序通则》对鉴定过程全程记录、可追溯的核心要求，确保每一份检验结果都具备完整的司法证据效力，可直接作为刑事诉讼、民事诉讼中的合法证据使用。
法定授权范围内的实战应用场景
本设备所有应用场景均严格遵守国家相关法律法规与司法鉴定技术规范，仅可由具备法医物证鉴定资质的机构与人员，在法定授权范围内规范操作，核心合规应用场景包括六大类：
严重暴力犯罪案件生物物证个体识别与同一认定
在严重暴力犯罪案件的侦办中，对现场提取的微量血迹、唾液斑、毛发、组织碎片、接触性脱落细胞等生物检材进行 DNA 提取与靶向扩增，获得完整的 STR 分型图谱，与涉案嫌疑人的 DNA 样本进行同一认定，或录入全国法医 DNA 数据库进行跨区域串并比对，直接锁定作案人员，为案件侦破提供核心的科学证据，还原案件事实，固定犯罪证据链。
失踪人员查找与未知名尸体身源司法鉴定
针对失踪人员查找、未知名尸体 / 尸骨身源认定工作，对现场提取的陈旧骨骼、牙齿、腐败组织等严重降解的生物检材，进行 DNA 提取与特异性扩增，通过常染色体 STR、Y-STR、线粒体 DNA 等多遗传标记系统分析，与失踪人员家属的 DNA 样本进行亲缘关系比对，科学、准确地确定未知名尸体的身源，为失踪人员查找、命案侦办、家属安抚提供客观的科学依据。
亲缘关系鉴定与被拐人员身份确认
在被拐儿童解救、寻亲团圆、抚养纠纷、遗产继承等民事与刑事案件中，通过扩增相关个体的 DNA 样本，分析 STR 等遗传标记的孟德尔遗传传递规律，科学判定父母与子女、全同胞、半同胞、祖孙等各类亲缘关系，为被拐儿童与亲生父母的亲缘确认、寻亲团圆提供核心科学证据，同时为民事纠纷中的亲缘关系判定提供合法有效的司法鉴定意见。
接触性犯罪案件微量脱落细胞 DNA 检验
在入室盗窃、抢劫、诈骗等接触性犯罪案件的侦办中，针对现场作案工具手柄、门窗把手、衣物纤维、眼镜架、饮料瓶、烟头等载体上附着的极微量脱落上皮细胞 DNA，进行高灵敏度扩增，成功获取嫌疑人的 DNA 分型图谱，为案件侦破提供关键线索，实现从 “无头案” 到 “有明确嫌疑人” 的侦查突破，是当前接触性犯罪案件侦办中最核心的技术支撑手段之一。
重大灾难事故遇难者大规模身份识别
在空难、火灾、地震、爆炸等重大突发灾难事故中，针对高度破坏、严重降解的遇难者遗体组织、骨骼、牙齿等检材，进行批量 DNA 提取与扩增，获得遇难者的 DNA 分型数据，通过与遇难者家属的 DNA 样本、遇难者生前生物样本进行比对，实现大规模遇难者的快速、准确身份识别，为事故善后处置、家属安抚提供科学、客观的依据。
法医 DNA 数据库标准化建设与批量样本处理
作为法医 DNA 实验室前端样本处理的核心设备，为各级公安法医 DNA 数据库、打拐 DNA 数据库、失踪人员 DNA 数据库，批量制备高质量、标准化的 DNA 扩增产物，支撑数据库的海量样本检验、数据入库与跨区域串并比对工作，实现 “从案到人、从人到案、从案到案” 的快速比对侦破，大幅提升刑事案件的侦办效率，构建全国一体化的 DNA 侦查技术防控体系。
核心技术参数
温控系统：采用半导体热电温控技术，最高升降温速率可达 4℃/ 秒，样品台温度控制范围为 0-100℃，温度控制精度高，适配各类 PCR 扩增程序的温控需求。
样品台性能：兼容 0.2ml×25 孔与 0.5ml×25 孔双规格反应体系，样品台温度均匀性≤±0.2℃，30-100℃范围内温度准确性≤±0.2℃，确保所有反应孔扩增反应的均一性与同步性。
程序控制能力：单组程序最多支持 40 个步骤编辑，支持温度与时间的递增 / 递减功能，可实现 Touchdown PCR、Long PCR、多重嵌套 PCR 等高级扩增策略；仪器内置可存储 120 组标准化程序，支持通过 U 盘实现无限量程序下载、存储与导出。
显示与通讯接口：配备 5.7 英寸彩色液晶显示屏，分辨率 320×240 像素，可实时显示温度曲线、程序进度与运行状态；配备 USB2.0 与 RS232 双通讯接口，支持程序导入导出、实验数据存档与实验室信息化系统对接。
热盖系统：热盖温度支持 30-105℃宽范围可调，热盖高度无级可调、压力自适应，完美兼容各类规格 PCR 管与反应板，具备程序结束自动关闭热盖功能，彻底杜绝反应液冷凝蒸发。
安全与辅助功能：具备程序结束后 4℃无限时样品保温功能、断电数据保护与程序恢复功能，支持热盖过温保护、样品台超温保护多重安全机制，保障实验安全与检材安全。
电源参数：输入功率 200-600W，适配常规实验室标准市电电源，满足实验室长期稳定运行的供电需求。
合规实战应用案例
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某市公安局刑事技术支队受理一起系列跨区域入室盗窃案件，犯罪嫌疑人在半年内流窜多地作案 30 余起，涉案金额巨大，犯罪嫌疑人反侦察意识极强，多数案发现场均未留下明显可辨识的痕迹物证，仅在多起案件现场的作案工具、门窗把手、被盗首饰盒上提取到了少量疑似嫌疑人接触遗留的微量脱落细胞检材，检材中 DNA 含量极低，属于疑难微量接触性检材。实验室检验人员使用本 PCR 基因扩增仪，针对该批微量检材优化了扩增程序，通过 Touchdown PCR 扩增策略，成功从 11 份疑难检材中扩增出完整的嫌疑人 STR 分型图谱，经检验获得了有效的 DNA 分型数据。技术人员将 DNA 分型录入全国法医 DNA 数据库进行比对，成功比中了有多次盗窃前科的嫌疑人赵某某，为案件锁定了核心嫌疑人。侦查人员根据 DNA 比对结果，成功抓获了犯罪嫌疑人赵某某，破获了该系列跨区域入室盗窃案件，带破省内同类案件 40 余起。本设备的高灵敏度扩增能力、精准的温控性能，成功实现了极微量脱落细胞检材的有效扩增，为案件的侦破提供了决定性的科学证据。
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某市江边发现一具未知名男性尸骨，尸体已高度腐败，仅存骨骼与牙齿，无任何可证明身份的随身物品，身源认定工作陷入僵局。法医提取了死者的股骨与牙齿检材，送往公安司法鉴定中心进行 DNA 检验。该检材属于陈旧尸骨，DNA 已发生严重降解，常规检验方法难以获得完整的 DNA 分型。检验人员使用本 PCR 基因扩增仪，针对骨骼降解检材优化了扩增循环参数与延伸程序，成功从牙齿与骨骼检材中扩增出完整的常染色体 STR 与 Y-STR 分型图谱。技术人员将分型数据录入失踪人员 DNA 数据库进行比对，同时与辖区内上报的失踪人员家属 DNA 样本进行亲缘比对，最终确认该未知名尸骨为辖区内失踪半年的男子王某某，成功完成了死者的身源认定。后续侦查人员根据身源认定结果，迅速查清了死者的社会关系与失踪前的活动轨迹，成功破获了该起刑事案件。本设备对严重降解检材的稳定扩增能力，为未知名尸体身源认定提供了关键的技术支撑，成为案件侦破的重要突破口。
Application Introduction of PCR Gene Amplification Instrument (Forensic DNA Analysis System) in Forensic Identification and Criminal Investigation
【Important Compliance Pre-Declaration】This equipment is the core laboratory equipment dedicated to forensic DNA identification and judicial authentication. It is only developed, produced and sold for state organs and authorized authentication institutions with legal forensic material evidence authentication qualifications, including public security organs, procuratorates, judicial administrative organs, and judicial authentication institutions, and will not be provided to any individual, unqualified enterprise or non-authorized unit. All operations and applications of this equipment must strictly abide by national laws, regulations and industry technical standards such as the Criminal Procedure Law of the People's Republic of China, General Rules for Judicial Authentication Procedures of the People's Republic of China, Forensic Science DNA Laboratory Specification, and Forensic Science DNA Inspection Specification. It must be operated in a standardized manner by professionals with forensic material evidence authentication qualifications within the scope of statutory authentication authority and authorized inspection. It is strictly prohibited for any unqualified unit and individual to carry out illegal and irregular acts such as DNA inspection without authorization and infringement of citizens' personal genetic information.
Product Overview
The PCR Gene Amplification Instrument (Forensic DNA Analysis System) is a core professional molecular biology equipment for forensic medicine built based on the core principle of Polymerase Chain Reaction (PCR). It is deeply customized for the efficient and specific amplification of DNA target fragments from trace, severely degraded and complex matrix biological samples extracted from criminal case scenes. Through the high-precision semiconductor temperature control system, the equipment drives the thermostable DNA polymerase to carry out exponential replication of specific gene sequences, which can amplify the trace amount of DNA template in the sample by billions of times, providing sufficient and qualified detection targets for subsequent judicial identification links such as STR typing, DNA sequence analysis and silver staining detection.
As the core key equipment in the whole process of forensic DNA inspection, its core value is that it can successfully amplify DNA fragments that meet the inspection requirements from various biological evidence such as a very small amount of blood stains, saliva stains, hair, bones, teeth, exfoliated epithelial cells extracted from the crime scene, and obtain a complete DNA map for individual identification. It is a key technical support platform to solve core problems such as the identification of involved persons in criminal cases, the identification of kinship, the search for the source of unknown corpses, and the identity confirmation of abducted persons. It is also a necessary basic equipment for forensic DNA laboratories of public security criminal technology departments and judicial authentication institutions at all levels.
Technical Principle
The core of the equipment works based on the in vitro nucleic acid amplification principle of Polymerase Chain Reaction (PCR). The temperature control accuracy, heating and cooling rate, and temperature uniformity of the equipment are the core keys to determine the success rate of DNA amplification, amplification specificity and result repeatability of forensic trace samples, and also the scientific basis to ensure that the inspection results have judicial evidence validity.
Through the high-performance semiconductor thermoelectric temperature control module, the equipment drives the PCR reaction system to carry out fast, accurate and repeatable cycle temperature control between three key temperature nodes to complete the exponential amplification of DNA: the first step is the high-temperature denaturation stage. Through the high-temperature environment of 94-95℃, the double-stranded DNA template is denatured and separated into single strands, providing a template for primer binding. The second step is the low-temperature annealing stage. Through the precise temperature control of 50-65℃, the specific primers are accurately and complementarily combined with the target sequence of the single-stranded DNA template to lock the amplification target. The third step is the medium-temperature extension stage. Through the constant temperature environment of 72℃, the activity of the thermostable DNA polymerase is activated, so that it synthesizes a new DNA complementary strand along the primer direction with the single-stranded DNA as the template, completing an amplification cycle.
Each complete cycle of "denaturation-annealing-extension" theoretically doubles the number of target DNA fragments. After 25-40 cycles, the target DNA fragments can achieve exponential amplification of billions of times, amplifying the originally undetectable trace DNA template to the detection level that can be used for STR typing and sequence analysis. The built-in intelligent control system of the equipment can carry out precise closed-loop control of the temperature, time and heating and cooling rate of each cycle, ensuring that the amplification reactions in all reaction wells are highly synchronized and uniform. Even for difficult forensic degraded samples with only pg-level trace DNA, efficient and specific amplification can be achieved, providing stable and reliable amplification products for subsequent judicial identification.
Core Functions and Compliance Practical Value
High-Precision and Fast Semiconductor Temperature Control Technology, Ensuring the Amplification Success Rate of Difficult Trace Samples
The equipment adopts industry-leading high-performance semiconductor thermoelectric modules, which can achieve a maximum heating and cooling rate of 4℃/s, greatly shortening the single amplification cycle time, significantly compressing the traditional amplification process of several hours, and greatly improving the processing efficiency of case samples in forensic laboratories. The temperature uniformity of the sample stage is ≤±0.2℃, and the temperature accuracy in the range of 30-100℃ is ≤±0.2℃, which can ensure that the amplification environment of all reaction wells in the 96-well/25-well reaction system is highly consistent, completely avoiding the problems of inter-well amplification efficiency difference, non-specific amplification and amplification failure caused by uneven temperature. Even for difficult degraded samples such as trace exfoliated cells, old bones and corrupt tissues extracted from the scene, stable and efficient specific amplification can be achieved, greatly improving the success rate of DNA inspection of difficult samples, and providing more key physical evidence clues for case detection.
Full-Scene Flexible Program Editing Capability, Adapting to the Needs of Forensic Diversified Genetic Marker Detection
The equipment has extremely strong flexibility in program editing, supporting up to 40 steps of multi-level program editing, and can realize a variety of advanced amplification strategies such as Touchdown PCR, Long PCR, and multiple nested PCR, which perfectly adapts to the diversified detection needs in forensic DNA inspection. The built-in storage space of the instrument can save 120 groups of standardized amplification programs, and supports unlimited program download and storage through U disk, which is convenient for the laboratory to establish a standardized inspection method library for different genetic markers such as autosomal STR, Y-STR, X-STR, mitochondrial DNA, as well as exclusive amplification programs for different types of samples such as fresh blood stains, saliva stains, old bones, and trace exfoliated cells. It can realize one-key call and standardized operation, ensuring that the inspection process of different batches and different types of samples is standardized and unified, fully complying with the laboratory accreditation and qualification certification requirements of judicial authentication institutions, and ensuring the repeatability, traceability and judicial validity of the inspection results.
Intelligent and Humanized Anti-Damage Design, Fully Ensuring the Safety of Precious Forensic Samples
Most of the biological samples extracted from the forensic scene are trace, non-reproducible precious physical evidence, and irreversible evidence loss will be caused once damaged or contaminated. The equipment is specially optimized for the forensic inspection scenario, equipped with a 5.7-inch color LCD screen, which can display the amplification temperature curve, program progress and inter-well temperature status in real time. The operator can monitor the amplification reaction status throughout the process and deal with abnormal situations in a timely manner. The hot cover adopts a stepless adjustable height and pressure adaptive design, which is perfectly compatible with PCR single tubes and reaction plates of various specifications of 0.2ml and 0.5ml. The temperature of the hot cover supports a wide range of adjustment from 30℃ to 105℃, which can ensure that the temperature of the tube cover is always higher than the temperature of the reaction liquid in the tube, completely eliminating the change of system concentration and amplification failure caused by evaporation and condensation of the reaction liquid, and avoiding the waste of precious samples. At the same time, the equipment has the functions of automatically closing the hot cover at the end of the program, unlimited sample insulation at 4℃, power-off protection and program recovery. Even in the case of sudden power failure, it will not cause sample damage and loss of experimental data, which maximally ensures the safety of precious forensic samples and the integrity of the experimental process.
High-Throughput Stable Operation Design, Adapting to Batch Sample Processing and DNA Database Construction
The sample stage of the equipment is compatible with dual specifications of 0.2ml×25 wells and 0.5ml×25 wells, taking into account the rapid detection of sporadic samples in daily cases and the high-throughput processing of batch samples. The whole machine adopts industrial-grade stable design, which can support 7×24 hours of continuous uninterrupted operation, and the temperature accuracy and amplification stability of long-term operation have no attenuation, which perfectly adapts to the dual needs of case inspection and database construction of forensic DNA laboratories of public security at all levels. The equipment supports the temperature and time increment/decrement function, which can meet the needs of amplification condition optimization for difficult samples and verification of new genetic marker systems in forensic laboratories. At the same time, it is equipped with USB2.0 and RS232 dual communication interfaces, which can realize batch export and traceability management of amplification programs and experimental data, which is in line with the requirements of whole-process informatization and standardized management of forensic DNA laboratories. It provides standardized and high-quality DNA amplification products for the construction of forensic DNA databases, and supports the massive data accumulation and efficient cross-regional comparison application of the database.
Whole-Process Traceable Management, Meeting the Core Requirements of Judicial Authentication Compliance
All core data such as amplification programs, operating parameters, temperature curves, and experimental time of the equipment can be completely recorded, exported and archived, and can be seamlessly connected with the LIMS laboratory information management system of the forensic DNA laboratory, realizing the whole process traceability and review from sample acceptance, DNA extraction, amplification, typing to report issuance, fully complying with the core requirements of the General Rules for Judicial Authentication Procedures for the whole process recording and traceability of the identification process, ensuring that each inspection result has complete judicial evidence validity and can be directly used as legal evidence in criminal proceedings and civil proceedings.
Practical Application Scenarios Within the Scope of Statutory Authorization
All application scenarios of this equipment strictly abide by the relevant national laws and regulations and judicial authentication technical specifications, and can only be operated in a standardized manner by institutions and personnel with forensic material evidence authentication qualifications within the scope of statutory authorization. The core compliant application scenarios include six categories:
Individual Identification and Matching of Biological Evidence in Serious Violent Crime Cases
In the investigation of serious violent crime cases, DNA extraction and targeted amplification are carried out on trace blood stains, saliva stains, hair, tissue fragments, contact exfoliated cells and other biological evidence extracted from the scene to obtain a complete STR typing map, which is matched with the DNA samples of the involved suspects, or entered into the national forensic DNA database for cross-regional serial comparison, directly locking the perpetrators, providing core scientific evidence for case detection, restoring the facts of the case, and fixing the criminal evidence chain.
Forensic Identification of Missing Persons Search and Unknown Corpse Source
For the search of missing persons and the identification of unknown corpses/remains, DNA extraction and specific amplification are carried out on severely degraded biological samples such as old bones, teeth and corrupt tissues extracted from the scene. Through the analysis of multiple genetic marker systems such as autosomal STR, Y-STR and mitochondrial DNA, the kinship comparison with the DNA samples of the families of missing persons is carried out to scientifically and accurately determine the source of the unknown corpse, providing an objective scientific basis for the search of missing persons, case investigation and family comfort.
Kinship Identification and Identity Confirmation of Abducted Persons
In civil and criminal cases such as the rescue of abducted children, family reunion, custody disputes and inheritance, by amplifying the DNA samples of relevant individuals, analyzing the Mendelian genetic transmission law of genetic markers such as STR, scientifically determining various kinship relationships such as parents and children, full siblings, half siblings, grandparents and grandchildren, providing core scientific evidence for the kinship confirmation and family reunion of abducted children and their biological parents, and providing legal and effective judicial authentication opinions for the determination of kinship in civil disputes.
DNA Inspection of Trace Exfoliated Cells in Contact Crime Cases
In the investigation of contact crime cases such as burglary, robbery and fraud, high-sensitivity amplification is carried out for the extremely trace amount of exfoliated epithelial cell DNA attached to the handles of crime tools, door and window handles, clothing fibers, spectacle frames, beverage bottles, cigarette butts and other carriers on the scene, successfully obtaining the DNA typing map of the suspect, providing key clues for case detection, realizing the investigation breakthrough from "headless case" to "clear suspect", which is one of the core technical support means in the current investigation of contact crime cases.
Large-Scale Identification of Victims in Major Disaster Accidents
In major sudden disaster accidents such as air crashes, fires, earthquakes and explosions, batch DNA extraction and amplification are carried out for the highly damaged and severely degraded victim remains tissues, bones, teeth and other samples to obtain the DNA typing data of the victims. Through comparison with the DNA samples of the victims' families and the biological samples of the victims before their death, rapid and accurate identification of large-scale victims is realized, providing a scientific and objective basis for the aftermath of the accident and family comfort.
Standardized Construction of Forensic DNA Database and Batch Sample Processing
As the core equipment for front-end sample processing in forensic DNA laboratories, it provides standardized and high-quality DNA amplification products for forensic DNA databases, anti-trafficking DNA databases, and missing person DNA databases at all levels of public security, supporting the massive sample inspection, data entry and cross-regional serial comparison of the database, realizing rapid comparison and detection of "from case to person, from person to case, from case to case", greatly improving the detection efficiency of criminal cases, and building a national integrated DNA investigation technology prevention and control system.
Core Technical Parameters
Temperature Control System: Adopting semiconductor thermoelectric temperature control technology, the maximum heating and cooling rate can reach 4℃/s, the temperature control range of the sample stage is 0-100℃, with high temperature control accuracy, adapting to the temperature control requirements of various PCR amplification programs.
Sample Stage Performance: Compatible with dual specification reaction systems of 0.2ml×25 wells and 0.5ml×25 wells, the temperature uniformity of the sample stage is ≤±0.2℃, and the temperature accuracy in the range of 30-100℃ is ≤±0.2℃, ensuring the uniformity and synchronization of the amplification reaction in all reaction wells.
Program Control Capability: A single program supports up to 40 steps of editing, supports temperature and time increment/decrement functions, and can realize advanced amplification strategies such as Touchdown PCR, Long PCR, and multiple nested PCR; the instrument has built-in storage for 120 groups of standardized programs, and supports unlimited program download, storage and export through U disk.
Display and Communication Interface: Equipped with a 5.7-inch color LCD screen with a resolution of 320×240 pixels, which can display the temperature curve, program progress and operating status in real time; equipped with USB2.0 and RS232 dual communication interfaces, supporting program import and export, experimental data archiving and docking with laboratory information system.
Hot Cover System: The temperature of the hot cover supports a wide range of adjustment from 30℃ to 105℃, the height of the hot cover is stepless adjustable and pressure adaptive, perfectly compatible with various specifications of PCR tubes and reaction plates, with the function of automatically closing the hot cover at the end of the program, completely eliminating the condensation and evaporation of the reaction liquid.
Safety and Auxiliary Functions: It has the function of unlimited sample insulation at 4℃ after the end of the program, power-off data protection and program recovery function, and supports multiple safety mechanisms such as hot cover over-temperature protection and sample stage over-temperature protection to ensure experimental safety and sample safety.
Power Supply Parameters: The input power is 200-600W, which adapts to the standard mains power supply of conventional laboratories and meets the power supply demand for long-term stable operation of the laboratory.
Compliance Practical Application Cases
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The Criminal Technology Detachment of the Municipal Public Security Bureau accepted a series of cross-regional burglary cases. The suspect fled to many places to commit more than 30 crimes within half a year, with a huge amount of money involved. The suspect had a strong sense of anti-investigation, and no obvious identifiable trace physical evidence was left at most of the crime scenes. Only a small amount of trace exfoliated cell samples suspected to be left by the suspect's contact were extracted from the crime tools, door and window handles, and stolen jewelry boxes at multiple crime scenes. The DNA content in the samples was extremely low, which belonged to difficult trace contact samples.
The laboratory inspectors used this PCR Gene Amplification Instrument, optimized the amplification program for this batch of trace samples, and successfully amplified the complete STR typing map of the suspect from 11 difficult samples through the Touchdown PCR amplification strategy, and obtained effective DNA typing data through inspection. The technicians entered the DNA typing into the national forensic DNA database for comparison, and successfully matched the suspect Zhao, who had many previous theft convictions, locking the core suspect for the case. According to the DNA comparison results, the investigators successfully arrested the criminal suspect Zhao, solved the series of cross-regional burglary cases, and uncovered more than 40 similar cases in the province. The high-sensitivity amplification capability and precise temperature control performance of this equipment successfully realized the effective amplification of extremely trace exfoliated cell samples, and provided decisive scientific evidence for the detection of the case.
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An unknown male skeleton was found by the river in a certain city. The body was highly corrupt, with only bones and teeth left, and no personal belongings to prove identity, so the work of body source identification fell into a deadlock. Forensic doctors extracted the femur and tooth samples of the deceased and sent them to the Public Security Judicial Authentication Center for DNA inspection. The sample was an old skeleton, and the DNA had been severely degraded, so it was difficult to obtain a complete DNA typing by conventional inspection methods.
The inspectors used this PCR Gene Amplification Instrument, optimized the amplification cycle parameters and extension program for the bone degraded samples, and successfully amplified the complete autosomal STR and Y-STR typing maps from the tooth and bone samples. The technicians entered the typing data into the missing person DNA database for comparison, and at the same time carried out kinship comparison with the DNA samples of the families of missing persons reported in the jurisdiction. Finally, it was confirmed that the unknown skeleton was Wang, a man who had been missing for half a year in the jurisdiction, and successfully completed the body source identification of the deceased.
Subsequent investigators quickly found out the social relations of the deceased and the activity track before the disappearance according to the results of body source identification, and successfully detected the criminal case. The stable amplification ability of this equipment for severely degraded samples provided key technical support for the identification of the source of unknown corpses, and became an important breakthrough in the detection of the case.