Biomedical SERS - the current state and future trends.

Surface enhanced Raman spectroscopy (SERS) is meeting the requirements in biomedical science being a highly sensitive and specific analytical tool. By employing portable Raman systems in combination with customized sample pre-treatment, point-of-care-testing (POCT) becomes feasible. Powerful SERS-active sensing surfaces with high stability and modification layers if required are available for testing and application in complex biological matrices such as body fluids, cells or tissues.

Role of Brown Adipose Tissue in Metabolic Health and Efficacy of Drug Treatment for Obesity.

(1) : Brown adipose tissue (BAT) is responsible for non-shivering thermogenesis, and its activation has become a new object as both a determinant of metabolic health and a target for therapy. This study aimed to identify the relationships between the presence of BAT, parameters that characterize metabolic health (glucose, lipids, blood pressure (BP)), and the dynamics of body mass index (BMI) during weight-reducing therapy. (2) : The study included 72 patients with obesity.

SERS as a tool for determination of structurally related compounds: The case of sulfanilamide class antibiotics.

Analysis of real objects based on surface-enhanced Raman spectroscopy (SERS) often utilizes new SERS substrates and/or complex analysis procedures, and they are optimized for only the determination of a single analyte. Moreover, analysis simplicity and selectivity are often sacrificed for maximum (sometimes unnecessary) sensitivity. Consequently, this trend limits the versatility of SERS analysis and complicates its practical implementation.

Cyclodextrin-assisted SERS determination of fluoroquinolone antibiotics in urine and blood plasma.

This paper describes the use of cyclodextrins (CDs) to improve the determination of fluoroquinolone antibiotics in human body fluids using surface-enhanced Raman spectroscopy (SERS). CDs were used to (i) prepare the CD-SERS substrate (synthesis and stabilization of silver nanoparticles), (ii) increase the sensitivity of the assay by enhancing the interaction between analyte molecules and the substrate, and (iii) improve the analysis accuracy by reducing the interaction between the substrate and endogenous components of body fluids. Two native CDs (α-CD and β-CD) and two of their derivatives with hydroxypropyl groups were tested, and the best results were obtained with CD-SERS substrate prepared using native β-CD.

Cyclodextrin-assisted surface-enhanced Raman spectroscopy: a critical review.

Numerous approaches have been proposed to overcome the intrinsically low selectivity of surface-enhanced Raman spectroscopy (SERS), and the modification of SERS substrates with diverse recognition molecules is one of such approaches. In contrast to the use of antibodies, aptamers, and molecularly imprinted polymers, application of cyclodextrins (CDs) is still developing with less than 100 papers since 1993. Therefore, the main goal of this review is the critical analysis of all available papers on the use of CDs in SERS analysis, including physicochemical studies of CD complexation and the effect of CD presence on the Raman enhancement.

Copper nanoparticles for SERS-based determination of some cephalosporin antibiotics in spiked human urine.

Copper nanoparticles (CuNPs) were prepared through a wet chemistry method to be used as substituents for noble-metal-based materials in the determination of cephalosporin antibiotics in urine using surface-enhanced Raman spectroscopy (SERS). The synthesis of the CuNPs was optimized to maximize the analytical signal, and microwave heating was used to increase the reaction rate and improve the homogeneity of the CuNPs. Ceftriaxone (CTR), cefazolin (CZL), and cefoperazone (CPR) were used as the analytes of interest.

Determination of methotrexate in spiked human urine using SERS-active sorbent.

This report is dedicated to determination of anticancer drug methotrexate (MTX) in human urine using surface-enhanced Raman spectroscopy (SERS). Aluminum oxide loaded with silver nanoparticles (AO-Ag) was proposed as SERS-active sorbent and used for solid-phase extraction (SPE) of the analyte and its SERS-based determination (SPE-SERS protocol). MTX has strong SERS signal only in alkaline media that challenges its determination in urine due to strong background signal caused by creatinine.

Liquid-liquid extraction-assisted SERS-based determination of sulfamethoxazole in spiked human urine.

The determination of antibiotic levels in body fluids is of great importance in the field of personalized medicine and therapeutic drug monitoring. We report on the determination of sulfamethoxazole (SMX), an antibacterial drug of the sulfanilamide class, in spiked human urine. The protocol is based on the combination of surface-enhanced Raman spectroscopy (SERS) and liquid-liquid extraction (LLE-SERS analysis).

Application of Aluminum Hydroxide for Improvement of Label-Free SERS Detection of Some Cephalosporin Antibiotics in Urine.

This report is dedicated to development of surface-enhanced Raman spectroscopy (SERS) based analysis protocol for detection of antibiotics in urine. The key step of the protocol is the pretreatment of urine before the detection to minimize background signal. The pretreatment includes extraction of intrinsic urine components using aluminum hydroxide gel (AHG) and further pH adjusting of the purified sample.

SERS detection of ceftriaxone and sulfadimethoxine using copper nanoparticles temporally protected by porous calcium carbonate.

The authors describe a new composite based on SERS-active copper nanoparticles (CuNPs; 10 ± 2 nm) incorporated into calcium carbonate microspheres (CaCO-CuNPs; 3.4 ± 0.3 μm).

Sample pretreatment and SERS-based detection of ceftriaxone in urine.

The aim of the work is the development of the procedure for ceftriaxone (antibiotic drug of cephalosporin class) detection in urine using surface-enhanced Raman spectroscopy (SERS). Hydroxylamine stabilized silver nanoparticles were used as SERS-active material. Additional urine pretreatment steps were developed in order to eliminate the influence of creatinine on the ceftriaxone SERS signal.