Goessling Johannes W, Martínez-Pérez Paula, Rodriguez-Lorenzo Laura, Braga-Fernandes Pedro, Espiña Begoña, Lopez-Garcia Martin
ECOMARE and Centro de Estudos do Ambiente e do Mar (CESAM) and Department of Biology, University of Aveiro, Aveiro 3810-193, Portugal.
Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, Valencia46022, Spain.
ACS Appl Nano Mater. 2025 Apr 11;8(16):7911-7919. doi: 10.1021/acsanm.4c06526. eCollection 2025 Apr 25.
Photonic band gap-based sensors can detect small variations in the refractive index of surrounding media, facilitating the precise detection of changes in their environment. In this proof-of-concept study, we demonstrate that biosilica produced by single-cell microalgae called diatoms can work as a photonic crystal slab sensor. We exploited the pseudo photonic bandgap (pseudo-PBG) produced by the highly periodic nanoscale morphology to detect the presence of relevant chemical elements in solutions. We demonstrate that the pseudo-PBG of the natural system can be calibrated for refractive index changes in the environment using standard liquids. Subsequently, we demonstrate that the platform enables precise detection of minute refractive index variations, accurate to the second decimal place, caused by concentration changes induced by analytes, such as magnesium chloride and d-glucose. This underscores the potential of nanostructured biosilica as an advanced platform for photonic sensing. In addition, we show that it is possible to customize the working spectral region by surface functionalization using titanium dioxide nanoparticles that modify the effective refractive index of the biosilica and therefore change the spectral properties of the pseudo-PBG. The results highlight the precision of this natural, biogenic nanomaterial and propose sustainable alternatives for developing photonic nanomaterials tailored for sensing applications and beyond.
基于光子带隙的传感器能够检测周围介质折射率的微小变化，有助于精确检测其环境中的变化。在这项概念验证研究中，我们证明了由单细胞微藻硅藻产生的生物二氧化硅可以作为光子晶体平板传感器。我们利用高度周期性纳米级形态产生的伪光子带隙（pseudo-PBG）来检测溶液中相关化学元素的存在。我们证明，使用标准液体可以针对环境中的折射率变化对天然系统的伪光子带隙进行校准。随后，我们证明该平台能够精确检测由分析物（如氯化镁和d-葡萄糖）引起的浓度变化所导致的折射率微小变化，精确到小数点后第二位。这突出了纳米结构生物二氧化硅作为光子传感先进平台的潜力。此外，我们表明通过使用二氧化钛纳米颗粒进行表面功能化来定制工作光谱区域是可行的，二氧化钛纳米颗粒会改变生物二氧化硅的有效折射率，从而改变伪光子带隙的光谱特性。结果突出了这种天然生物源纳米材料的精度，并为开发用于传感应用及其他领域的光子纳米材料提出了可持续的替代方案。
