Analytical techniques for multiplex analysis of protein biomarkers

Introduction: The importance of biomarkers for pharmaceutical drug development and clinical diagnostics is more significant than ever in the current shift toward personalized medicine. Biomarkers have taken a central position either as companion markers to support drug development and patient selection, or as indicators aiming to detect the earliest perturbations indicative of disease, minimizing therapeutic intervention or even enabling disease reversal. Protein biomarkers are of particular interest given their central role in biochemical pathways. Hence, capabilities to analyze multiple protein biomarkers in one assay are highly interesting for biomedical research. Areas covered: We here review multiple methods that are suitable for robust, high throughput, standardized, and affordable analysis of protein biomarkers in a multiplex format. We describe innovative developments in immunoassays, the vanguard of methods in clinical laboratories, and mass spectrometry, increasingly implemented for protein biomarker analysis. Moreover, emerging techniques are discussed with potentially improved protein capture, separation, and detection that will further boost multiplex analyses. Expert commentary: The development of clinically applied multiplex protein biomarker assays is essential as multi-protein signatures provide more comprehensive information about biological systems than single biomarkers, leading to improved insights in mechanisms of disease, diagnostics, and the effect of personalized medicine

Perspectives of Molecularly Imprinted Polymer-Based Drug Delivery Systems in Ocular Therapy

Although the human eye is an easily accessible sensory organ, it remains a challenge for drug administration due to the presence of several anatomical and physiological barriers which limit the access of drugs to its internal structures. Molecular imprinting technology may be considered the avant-garde approach in advanced drug delivery applications and, in particular, in ocular therapy. In fact, molecularly imprinted polymers hold the promise to compensate for the current shortcomings of the available arsenal of drug delivery systems intended for ocular therapy. The present manuscript aims to review the recent advances, the current challenges and most importantly to raise awareness on the underexplored potential and future perspectives of molecularly imprinted polymer-based drug delivery systems intended for the treatment of eye diseases

Zein Nanoparticles Uptake and Translocation in Hydroponically Grown Sugar Cane Plants

The main objective of this study was to investigate the uptake and translocation of positively charged zein nanoparticles (ZNPs) in hydroponically grown sugar cane plants. Fluorescent ZNPs (spherical and measuring an average diameter 135 ± 3 nm) were synthesized by emulsion-diffusion method from FITC-tagged zein. Fluorescent measurement following digestion of plant tissue indicated that sugar cane roots had a significant adhesion of ZNPs, 342.5 ± 24.2 μg NPs/mg of dry matter, while sugar cane leaves contained a very limited amount, 12.9 ± 1.2 μg NPs/mg dry matter for high dose(1.75 mg/ml) after 12 h. Confocal microscopy studies confirmed presence of fluorescent ZNPs in the epidermis and endodermis of the root system. Given their ability to adhere to roots for extended periods of time, ZNPs are proposed as effective delivery systems for agrochemicals to sugar cane plants, but more studies are needed to identify effect of nanoparticle exposure to health of the plant

Zein Nanoparticles Uptake by Hydroponically Grown Soybean Plants

In the interest of developing and characterizing a polymeric nanoparticle pesticide delivery vehicle to soybeans, zein nanoparticle (ZNP) uptake by the roots and biodistribution to the leaves of soybean plants was measured. Zein was tagged with fluorescein isothiocyanate (FITC) and made into nanoparticles (135 ± 3 nm diameter. 0.202 ± 0.034 PDI and 81 ± 4 mV zeta-potential at pH 6) using an emulsion-diffusion method. After 10 days of hydroponic exposure, association between particles and roots of plants was found to vary based on bulk nanoparticle concentration. While 0.37 mg NP/mg dry weight were detected in roots immersed in 0.88 mg NP/mL nanoparticle suspension, 0.58 mg NP/mg dry weight associated with roots immersed in a high dose nanoparticle suspension of 1.75 mg NP/mL at 10 days. Nanoparticle root uptake followed second order kinetics. A small amount of increased fluorescence was detected in the hydroponically exposed plant\u27s leaves, suggesting that either small amounts of particles or other fluorescent contaminants of zein were up taken by the roots and biodistributed within the plant. To the authors\u27 knowledge, this is the first study in which the uptake and time-dependent association between polymeric nanoparticles and soybeans are quantified

Toxicity and biouptake of lead and arsenic by Daphnia pulex

Cataracts are responsible for half of the world blindness, surgery being the only viable treatment. Lutein, a naturally occurring carotenoid in the eye, has the potential to reduce cataract progression by protecting the eye from photo-oxidative stress. To restore the eye\u27s natural line of defense against photo-oxidative stress, a formulation was developed using zein and poly(lactic-co-glycolic acid) nanoparticles (NPs) embedded in an optimized bioadhesive thermosensitive gel for the delivery of lutein via topical application. Cataracts were induced in Crl:WI rats via selenite injection at 13 days post-partum, followed by 7 days of treatment with free lutein or lutein-loaded NPs administered orally or topically. Cataract severity was significantly reduced in rats treated with topical applications of lutein-loaded NPs compared to the positive control, while no significant differences were observed in rats treated with other lutein formulations including oral and topically applied free lutein

A chiral electrochemical system based on l-cysteine modified gold nanoparticles for propranolol enantiodiscrimination: Electroanalysis and computational modelling

Enantioselective electrochemical sensors seem to hold the promise for a fast and easy alternative for the chiral probing of bioactive molecules. However, the underlying mechanism responsible for the chiral recognition is rarely known, and suitable investigational tools are dearly missed. Therefore, as a proof-ofconcept, our study is focused on investigating the interaction mechanism of the enantiomers of a chiral drug molecule, namely propranolol (PRNL) with the surface of bare and L-cysteine (L-Cys) modified gold nanoparticles employing various electrochemical techniques (differential pulse voltammetry and electrochemical impedance spectroscopy) and computational modeling (molecular dynamics simulations). If the strong surface adsorption of PRNL antipodes on bare gold nanoparticles may not be exploited for enantioselective recognition, upon the functionalization of the nanostructures with L-Cys, the almost two fold increase in the oxidation current is also accompanied by a cathodic shift (~40 mV) of the peak potential for the S( )-enantiomer. This peak potential shift seems to be the consequence of a favored orientation of the surface adsorbed S( )-enantiomer towards electron transfer and/or a weaker interaction with the chiral selector and thus a higher free energy of the transient diastereoisomeric complex, in comparison with its R(þ)-antipode. Computational modeling highlighted the H-bond donor and acceptor atoms of both the chiral selector (L-Cys) and adsorbates (PRNL enantiomers) responsible for the recorded enantioselective electrochemical signal. Correlations between the observed electrochemical signal and enantioselective molecular interactions occurring at the surface of the electrode may lead the way towards a more rational design of future chiral electrochemical sensing platforms