Accurate medical recordkeeping is a major challenge in many low-resource settings where well-maintained centralized databases do not exist, contributing to 1.5 million vaccine-preventable deaths annually. Here, we present an approach to encode medical history on a patient using the spatial distribution of biocompatible, near-infrared quantum dots (NIR QDs) in the dermis. QDs are invisible to the naked eye yet detectable when exposed to NIR light. QDs with a copper indium selenide core and aluminum-doped zinc sulfide shell were tuned to emit in the NIR spectrum by controlling stoichiometry and shelling time. The formulation showing the greatest resistance to photobleaching after simulated sunlight exposure (5-year equivalence) through pigmented human skin was encapsulated in microparticles for use in vivo. In parallel, microneedle geometry was optimized in silico and validated ex vivo using porcine and synthetic human skin. QD-containing microparticles were then embedded in dissolvable microneedles and administered to rats with or without a vaccine. Longitudinal in vivo imaging using a smartphone adapted to detect NIR light demonstrated that microneedle-delivered QD patterns remained bright and could be accurately identified using a machine learning algorithm 9 months after application. In addition, codelivery with inactivated poliovirus vaccine produced neutralizing antibody titers above the threshold considered protective. These findings suggest that intradermal QDs can be used to reliably encode information and can be delivered with a vaccine, which may be particularly valuable in the developing world and open up new avenues for decentralized data storage and biosensing.

中文翻译：

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通过微针贴片传递到皮肤的生物相容性近红外量子点记录了疫苗接种情况。

在许多资源匮乏的地方，准确的医疗记录保存是一项重大挑战，在这些地方，不存在维护良好的集中式数据库，每年造成150万人可通过疫苗预防的死亡。在这里，我们提出一种使用真皮中生物相容性，近红外量子点（NIR QDs）的空间分布对患者的病史进行编码的方法。量子点是肉眼看不见的，但暴露在近红外光下却可以检测到。通过控制化学计量和脱壳时间，对具有铜铟硒化物核和铝掺杂硫化锌壳的量子点进行调谐，使其在近红外光谱中发光。在通过有色人皮肤进行模拟日光照射（相当于5年）后，显示出对光漂白的最大抵抗力的制剂被封装在微粒中，以供体内使用。在平行下，在计算机上优化了微针的几何形状，并使用猪和人造人皮肤进行了离体验证。然后将含有QD的微粒包埋在可溶解的微针中，并在有或没有疫苗的情况下施用于大鼠。使用适用于检测NIR光的智能手机进行的纵向体内成像表明，微针递送的QD图案保持明亮，可以在应用后9个月使用机器学习算法进行准确识别。另外，灭活的脊髓灰质炎病毒疫苗的代码传递产生的中和抗体滴度高于被认为具有保护作用的阈值。这些发现表明，皮内QD可用于可靠地编码信息，并可与疫苗一起提供，