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Abstract The concentration of dopamine (DA) and tyrosine (Tyr) reflects the condition of patients with Parkinson's disease, whereas moderate paracetamol (PA) can help relieve their pain. Therefore, real‐time measurements of these bioanalytes have important clinical implications for patients with Parkinson's disease. However, previous sensors suffer from either limited sensitivity or complex fabrication and integration processes. This work introduces a simple and cost‐effective method to prepare high‐quality, flexible titanium dioxide (TiO2) thin films with highly reactive (001)‐facets. The as‐fabricated TiO2film supported by a carbon cloth electrode (i.e., TiO2–CC) allows excellent electrochemical specificity and sensitivity to DA (1.390 µA µM−1 cm−2), Tyr (0.126 µA µM−1 cm−2), and PA (0.0841 µA µM−1 cm−2). More importantly, accurate DA concentration in varied pH conditions can be obtained by decoupling them within a single differential pulse voltammetry measurement without additional sensing units. The TiO2–CC electrochemical sensor can be integrated into a smart diaper to detect the trace amount of DA or an integrated skin‐interfaced patch with microfluidic sampling and wireless transmission units for real‐time detection of the sweat Try and PA concentration. The wearable sensor based on TiO2–CC prepared by facile manufacturing methods holds great potential in the daily health monitoring and care of patients with neurological disorders.
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This content will become publicly available on January 1, 2027
Catalytic TiO 2 with Self‐Assembled Monolayer for Highly Sensitive, Selective, and Non‐Invasive Monitoring of Sweat L‐Cysteine
Abstract L‐cysteine plays a significant role in numerous physiological processes in the human body health, and monitoring its level has important clinical implications. However, L‐cysteine tests are limited to invasive blood drawing and a time‐consuming laboratory process, which also fails to give real‐time and continuous results. This study introduces a flexible electrochemical sensor based on a self‐assembled monolayer (SAM) of 3‐mercaptopropyltrimethoxysilane (MPTS) molecular receptor and catalytic titanium oxide‐modified carbon cloth (MPTS/TiO2/CC). The MPTS and TiO2modification serve as the artificial antibody through thiol interactions and the charge transfer layer, respectively, which is further confirmed by density function theory (DFT) calculations. The flexible L‐cysteine sensor based on MPTS/TiO2/CC shows a wide linear range of up to 500 µmand an ultra‐low limit of detection of 0.046 µm. A sweat patch consisting of an electrochemical sensing unit, a laser‐fabricated microfluidic channel, and a miniaturized electrochemical workstation affords real‐time monitoring of L‐cysteine detection in dynamic environments and reveals the strong correlation between sweat and blood L‐cysteine concentrations. The introduction of molecular receptors and band alignment may offer a general way of designing sensitive, specific electrochemical sensors for point‐of‐care diagnosis.
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- PAR ID:
- 10694951
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 36
- Issue:
- 8
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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