A simple and efficient post-labeling strategy based on dye-induced peeling of the aptamer molecules off single-walled carbon nanotubes was developed for electrochemical aptasensing of thrombin with a detection limit down to 3 pM.

We reported a reactive probe for HSO3(-), which showed a colorimetric and ratiometric fluorescence response to HSO3(-) with fast response (t1/2 = 20 s), good specificity and low detection limit (3.0 nM). The probe was cell membrane permeable and successfully used for visualizing trace SO2 derivatives in living cells.

The limit of detection (LOD) for any analytical procedure, the point at which analysis is just feasible, may be determined by a statistical approach based on measuring replicate blank (negative) samples or by an empirical approach, consisting of measuring progressively more dilute concentrations of analyte. The limit of quantitation (LOQ), or concentration at which quantitative results can be r...

A general, overarching theme in nanotechnology is the integration of multiple disparate fields to realize novel or expanded functionalities. Here, we present a graphene enabled, integrated optoelectromechanical device and demonstrate its utility for biomolecular sensing. We experimentally achieve an ultrawide linear dynamic sensing range of 5 orders of magnitude of protein concentration, an imp...

OBJECTIVES This study was designed to evaluate the analytical performance of the novel Lumipulse G1200 BRAHMS procalcitonin (PCT) immunoassay. DESIGN AND METHODS This analytical evaluation encompassed the calculation of the limit of blank (LOB), limit of detection (LOD), functional sensitivity, intra- and inter-assay imprecision, confirmation of linearity and a comparison with the Vidas BRAHM...

Losartan potassium, Valsartan , Telmisartan and Irbesartan are angiotensin-II-receptor antagonists (ARA II) group which used in treatment of hypertension alone or in combination with other drugs mainly Hydrochlorothiazide. RP- HPLC method was developed for the assay of three angiotensin-II-receptor antagonists (ARA-IIs) in presence of Hydrochlorothiazide. The method was performed by reversed ph...

A new optimization strategy for the SERS detection of mephedrone using a portable Raman system has been developed. A fractional factorial design was employed, and the number of statistically significant experiments (288) was greatly reduced from the actual total number of experiments (1722), which minimized the workload while maintaining the statistical integrity of the results. A number of con...

We describe a simple and selective method for analysing propranolol and a sensitive test for its control in urine. A flow-through fluorescence optosensor based on on-line immobilization in a non-ionic-exchanger (Amberlite XAD-7) solid support in a continuous flow was used in both cases. Determination was made in 5 mM H(2)PO(4)(-)/HPO(4)(2-) buffer solution at pH 6 at a working temperature of 20...

An ultrasensitive CO(2) sensor with a detection limit of 500 ppt was achieved using poly(ionic liquid)-wrapped single-walled carbon nanotubes as sensing materials. The sensor exhibited superior selectivity to CO(2) and was resistant to the interference of relative humidity.

Given the importance of protease's worldwide market, the determination of optimum conditions and the development of a standard protocol are critical during selection of a reliable method to determine its bioactivity. This paper uses quality control theory to validate a modified version of a method proposed by Charney and Tomarelli in 1947. The results obtained showed that using azocasein substr...