Circularly Polarised Luminescent Photography and Lanthanide Complexes for Advanced Intelligent Security Applications

用于高级智能安全应用的圆偏振发光摄影和稀土配合物

• 批准号: EP/X040259/1
• 负责人: Robert Pal
• 金额: $ 37.65万
• 依托单位: Durham University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX040259%2F1
• 关键词: Circularly; Polarised; Luminescent; Photography; Lanthanide

Counterfeiting is extremely detrimental to society. Authenticating products and documents is vital to global commerce, health and personal identity. A plethora of noticeable and concealed anti-counterfeiting measures and technologies have been developed to combat counterfeiting. Perhaps the most well-known class of anti-counterfeiting labels are luminescent security inks, which are commonly applied to bank notes and passports. Lanthanide complexes are widely used in luminescent security inks due to their unique and robust photophysical properties such as fingerprintlike emission profiles and long luminescent lifetimes. The proposed project will harness the phenomenon of Circularly Polarised Luminescence (CPL), where different enantiomers of the same chemical entity produce different handedness (left or right) of light. Lanthanide complexes can be engineered to emit CPL, which encodes chiral molecular fingerprints in luminescence spectra that cannot be decoded by conventional optical measurements. However, chiral CPL signals have not yet been exploited as an extra security layer in advanced security inks due to the lack of suitable handheld rapid 'ad-hoc' CPL detection technology.Over the past decade, we have led the way in the development of CPL active bright optical probes and dyes based on lanthanide luminescence (Dalton Trans., 2015 ,44, 4791-4803). Several Ln(III) complexes possess high thermal stability and resistance, with complete CPL fingerprint preservation, making them suitable candidates (Chem. Sci., 2018, 9, 1042-1049) to be used as extra layers in hidden Chameleon Security Inks (CSI).CSI's combine organic short-lived (ns) green/blue emitters and chiral (CPL active) red/green (terbium/europium) long-lived (ms) emitters embedded into transparent polymer matrices. They pave the way towards multi-layered: multi-coloured, -spectral, -helicity, high spatial and temporal resolution unclonable QR code generation with an unprecedented 5 layers of 'invisible to the naked eye' security. The wide-spread use of 'plastic' banknotes facilitates the introduction of 'hidden in plain sight' CSI features, when combined with the right instrument can facilitate ad-hoc verification further advancing security and authenticity. In 2020 our pioneering solid-state CPL spectrometer (Nat. Commun., 2020, 11, 1676) triggered a paradigm shift in CPL spectroscopy that has been hindered over the last 50 years due to its stagnant design that prevented its use and widespread application. For the first time, our novel CPL spectrometer allowed rapid time-resolved CPL spectroscopy to be exploited. Earlier this year (Nat. Commun., 2022, 13, 553) we constructed and validated the world's first CPL Laser Scanning Confocal Microscope (CPL-LSCM), which is uniquely capable of simultaneously recording left- and right-handed CPL allowing enantioselective differential chiral contrast (EDCC) imaging of emissive chiral molecules, yet again igniting and broadening the horizon of CPL research. In this project we set out to adapt and embed our patented CPL chiroptical separator unit into a hand-held, solid-state CPL photographic (CPLP) camera system. Once it is fully developed and validated it can be used for 'ad-hoc' time-resolved EDCC measurements. This could truly amplify the underlying potential of CPL and pave the way towards novel unclonable luminescent security inks. Harnessing the so far unexploited benefits of CPL detection would allow the broad communities of life and material sciences to adopt this facile technology. We forecast a potentially game-changing impact on a global scale that reaches further than the scientific benefits associated with this project and could generate immense commercial interest.

假冒伪劣行为对社会危害极大。认证产品和文件对于全球商业、健康和个人身份至关重要。为了打击假冒伪劣行为，人们开发了多种明显的和隐蔽的防伪措施和技术。也许最著名的一类防伪标签是发光安全油墨，通常应用于钞票和护照。镧系元素络合物因其独特而强大的光物理特性（例如指纹发射曲线和长发光寿命）而广泛用于发光安全油墨。拟议的项目将利用圆偏振发光（CPL）现象，即同一化学实体的不同对映体产生不同的旋光性（左旋或右旋）光。镧系元素配合物可以被设计为发射 CPL，它在发光光谱中编码无法通过传统光学测量解码的手性分子指纹。然而，由于缺乏合适的手持式快速“临时”CPL 检测技术，手性 CPL 信号尚未被用作高级安全油墨中的额外安全层。在过去的十年中，我们在开发基于镧系元素发光的 CPL 活性明亮光学探针和染料（Dalton Trans., 2015 ,44, 4791-4803）。几种 Ln(III) 配合物具有高热稳定性和耐热性，具有完整的 CPL 指纹保留，使其成为合适的候选者 (Chem. Sci., 2018, 9, 1042-1049)，可用作隐藏 Chameleon 安全油墨 (CSI) 中的额外层).CSI 结合了有机短寿命 (ns) 绿/蓝发射体和手性（CPL 活性）红/绿（铽/铕）长寿命 (ms)发射器嵌入透明聚合物基质中。它们为多层化铺平了道路：多色、光谱、螺旋性、高空间和时间分辨率的不可克隆 QR 码生成，具有前所未有的 5 层“肉眼不可见”安全性。 “塑料”纸币的广泛使用有助于引入“隐藏在显而易见的”CSI 功能，与正确的工具相结合可以促进临时验证，进一步提高安全性和真实性。 2020 年，我们开创性的固态 CPL 光谱仪 (Nat. Commun., 2020, 11, 1676) 引发了 CPL 光谱学的范式转变，而这种转变在过去 50 年来一直受到阻碍，因为其停滞的设计阻碍了其使用和广泛应用。我们的新型 CPL 光谱仪首次实现了快速时间分辨 CPL 光谱的开发。今年早些时候 (Nat. Commun., 2022, 13, 553)，我们构建并验证了世界上第一台 CPL 激光扫描共焦显微镜 (CPL-LSCM)，它具有独特的能力，可以同时记录左手和右手 CPL，从而实现对映选择性微分发射手性分子的手性对比 (EDCC) 成像，再次点燃并拓宽了 CPL 研究的视野。在这个项目中，我们着手将我们获得专利的 CPL 手性光学分离器单元改编并嵌入到手持式固态 CPL 摄影 (CPLP) 相机系统中。一旦完全开发和验证，它就可以用于“临时”时间分辨 EDCC 测量。这可以真正放大 CPL 的潜在潜力，并为新型不可克隆发光安全墨水铺平道路。利用 CPL 检测迄今为止尚未开发的优势将使生命和材料科学领域的广泛社区能够采用这种简便的技术。我们预测，该项目可能会在全球范围内产生改变游戏规则的影响，其影响将超出与该项目相关的科学效益，并可能产生巨大的商业利益。