Garehbaghi Sanam, Richtera Lukas, Altintas Zeynep, Ashrafi Amir M
Central European Institute of Technology, Brno University of Technology, Brno 61200, Czech Republic.
Department of Chemistry and Biochemistry, Mendel University in Brno, Brno 61300, Czech Republic.
ACS Omega. 2025 Aug 24;10(35):40324-40334. doi: 10.1021/acsomega.5c05564. eCollection 2025 Sep 9.
The platinum nanozymes capped with tyrosine (Pt-Tyr NZ) were synthesized which demonstrated peroxidase and oxidase catalytic activities toward 3,3',5,5'-tetramethylbenzidine (TMB). The kinetic analyses revealed that Pt-Tyr NZ exhibited higher catalytic activity and substrate affinity for both HO and TMB compared to horseradish peroxidase (HRP), indicating its superior efficiency in biosensing applications. The synthesized Pt-Tyr NZ was reversibly conjugated with complementary DNA (cDNA), which can selectively hybridize with miRNA-21, a cancer biomarker, and after hybridization with miRNA-21, detaches from the surface of Pt-Tyr NZ. Upon cDNA conjugation, the catalytic activity of Pt-Tyr NZ decreased, but it was restored in the presence of miRNA-21, providing a one-step spectrophotometric biosensing method for miRNA-21 determination. Optimization of parameters affecting the sensitivity of the developed method for miRNA-21 detection was performed, including the tyrosine-to-platinum ratio in Pt-Tyr NZ synthesis, Pt-Tyr NZ concentration, and cDNA concentration for conjugation. The developed method was fully validated and showed promising results in terms of reproducibility (RSD = 1.26%, 95% confidence interval = 0.03, = 6), repeatability (RSD = 0.83%, = 5), and accuracy for spiked miRNA-21 determination in 10% filtered human serum samples (recovery rate = 109.7 ± 4.2%). It showed a linear dynamic range (LDR) from 37.1 to 185 nM, with a limit of detection (LOD) of 11.1 nM and a limit of quantification (LOQ) of 36.9 nM.
合成了以酪氨酸封端的铂纳米酶（Pt-Tyr NZ），其对3,3',5,5'-四甲基联苯胺（TMB）表现出过氧化物酶和氧化酶催化活性。动力学分析表明，与辣根过氧化物酶（HRP）相比，Pt-Tyr NZ对H₂O₂和TMB均表现出更高的催化活性和底物亲和力，表明其在生物传感应用中具有更高的效率。合成的Pt-Tyr NZ与互补DNA（cDNA）可逆结合，该cDNA可与癌症生物标志物miRNA-21选择性杂交，与miRNA-21杂交后从Pt-Tyr NZ表面脱离。cDNA结合后，Pt-Tyr NZ的催化活性降低，但在miRNA-21存在时恢复，为miRNA-21的测定提供了一种一步分光光度法生物传感方法。对影响所开发的miRNA-21检测方法灵敏度的参数进行了优化，包括Pt-Tyr NZ合成中的酪氨酸与铂比例、Pt-Tyr NZ浓度以及结合的cDNA浓度。所开发的方法经过了充分验证，在重复性（RSD = 1.26%，95%置信区间 = 0.03，n = 6）、可重复性（RSD = 0.83%，n = 5）以及在10%过滤人血清样品中加标miRNA-21测定的准确性（回收率 = 109.7 ± 4.2%）方面均显示出有前景的结果。它显示出从37.1到185 nM的线性动态范围（LDR），检测限（LOD）为11.1 nM，定量限（LOQ）为36.9 nM。
