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Although still commonly used in clinical practice to screen and diagnose prostate cancer, there are numerous weaknesses of prostate-specific antigen (PSA) testing, including lack of specificity and the inability to distinguish between aggressive and indolent cancers. A promising prostate cancer biomarker, alpha-methylacyl-CoA racemase (AMACR), has been previously demonstrated to distinguish cancer from healthy and benign prostate cells with high sensitivity and specificity. However, no accurate clinically useful assay has been developed. This study reports the development of a single use, disposable biosensor for AMACR detection. Human blood samples were used to verify its validity, reproducibility and reliability. Plasma samples from 9 healthy males, 10 patients with high grade prostatic intraepithelial neoplasia (HGPIN), and 5 prostate cancer patients were measured for AMACR levels. The average AMACR levels in the prostate cancer patients was 10 fold higher (mean(SD) = 0.077 (0.10)) than either the controls (mean(SD) = 0.005 (0.001)) or HGPIN patients (mean(SD) = 0.004 (0.0005)). At a cutoff of between 0.08 and 0.9, we are able to achieve 100% accuracy in separating prostate cancer patients from controls. Our results provide strong evidence demonstrating that this biosensor can perform as a reliable assay for prostate cancer detection and diagnosis.

A bimetallic Pt-Ru nanoparticle catalyst was prepared and characterized for the enhancement of hydrogen peroxide (H2O2) detection in biosensing applications. The particles were synthesized via sodium borohydride reduction, with low heat treatment, and characterized by TEM and HRTEM. The chemical composition analyses were performed by EDX. The bimetallic particle diameters ranged from 2 to 12 nm, with an average of 4.5 nm. The Pt-Ru catalyst exhibited an improved performance at low overpotential (+0.2 V versus Ag/AgCl reference electrode) in H2O2detection, suggesting a sensitivity value of 78.95 μA⋅mM-1(or 402.1 μA⋅mM-1⋅cm-2) which was 30% higher than that for the single Pt catalyst. The major contribution of this enhancement comes from the stronger oxygen adsorption on Ru metal. The Pt-Ru catalyst also showed a more stable signal at the high overpotential (+0.4 V versus Ag/AgCl), providing better accuracy in the detection of H2O2.

Cyanuric acid is often found to be the end product in the hydrolysis of waste melamine and in the TiO2-mediated photocatalytic decomposition of s-triazine-containing compounds used as herbicides or dyes. The photocatalytically recalcitrant nature of cyanuric acid on TiO2 may be closely related to its adsorption properties, including the tautomeric forms present on the surfaces and their bonding structures, which remain to be determined. In this paper, we present the optimized adsorption structures of the four tautomeric isomers (triketo, diketo, monoketo, and triol) of cyanuric acid on a model rutile-TiO2(110) surface and their vibrational absorptions. Experimentally, the adsorption structures of cyanuric acid and chloride on powdered TiO2 are analyzed on the basis of the theoretically obtained, characteristic infrared information. Cyanuric acid on TiO2 at 35 °C exists in triketo and hydroxylated forms, but the diketo becomes the predominant form on the surface at 250 °C, being bonded to a titanium site via one of its carbonyl groups and with a N-H···O hydrogen bonding interaction. Hydroxylation of cyanuric chloride occurs as it is adsorbed on TiO2 at 35 °C. Upon being heated to 200 °C, the surface is mainly covered with the diketo form of cyanuric acid after the adsorption of cyanuric chloride.

Acetone is generated upon mesityl oxide (MO) adsorption on TiO2 at 35°C. Water plays an important role in promoting MO decomposition to form acetone. It is suggested that diacetone alcohol plays a role in the transformation of MO to acetone. The thermal reaction of pinacol on TiO2 mainly produces pinacolone at a temperature higher than 100°C. However, acetone is mainly formed in the photocatalytic decomposition of pinacol on TiO2 in O2. Pinacolone is thermally transformed into 2,3‐dimethyl‐1,3‐butadiene in the absence of O2 and into pivalate in the presence of O2. Both the reactions of pinacolone occur above 200°C.

Aldol condensation of CH3CHO, forming crotonaldehyde (2-butenal, CH3CHCHCHO), readily occurs on TiO2 at 35 °C. At a higher coverage or at an elevated temperature, the crotonaldehyde can be oxidized to crotonate. Adsorption and thermal reactions of CH3CHBr2, BrCH2CH2Br, BrCH2CH2OH, and ClCH2CH2OH on TiO2 can produce crotonaldehyde, in contrast to CH2CHBr. CH3CHBr2 has the highest reactivity toward the crotonaldehyde formation among the halogenated compounds studied. The pathways of CH3CHBr2 + Ti–O–Ti → CH3CHO + 2Ti–Br and BrCH2CH2Br + Ti–O–Ti → Ti–O–CH2CH2Br + Ti–Br → CH3CHO +2 Ti–Br are proposed for the reactions of CH3CHBr2 and BrCH2CH2Br. The crotonaldehyde generated from the reactions of the four halogenated compounds on TiO2 has lower CO and CC stretching frequencies as compared to those of the crotonaldehyde directly from its adsorption on TiO2. This result is attributed to the presence of Br or Cl atoms near the crotonaldehyde adsorption sites and the change in the Ti ionic bonding environment. In addition, photoirradiation (325 nm) on ClCH2CH2OH on TiO2 can enhance the crotonaldehyde formation.