Surface plasmon resonance study of the interaction of a beta-cyclodextrin polymer and hydrophobically modified poly(N-isopropylacrylamide)

Cyclodextrin Host-Guest Recognition in Glucose-Monitoring Sensors

Diabetes mellitus is a prevalent chronic health condition that has caused millions of deaths worldwide. Monitoring blood glucose levels is crucial in diabetes management, aiding in clinical decision making and reducing the incidence of hypoglycemic episodes, thereby decreasing morbidity and mortality rates. Despite advancements in glucose monitoring (GM), the development of noninvasive, rapid, accurate, sensitive, selective, and stable systems for continuous monitoring remains a challenge. Addressing these challenges is critical to improving the clinical utility of GM technologies in diabetes management. In this concept, cyclodextrins (CDs) can be instrumental in the development of GM systems due to their high supramolecular recognition capabilities based on the host-guest interaction. The introduction of CDs into GM systems not only impacts the sensitivity, selectivity, and detection limit of the monitoring process but also improves biocompatibility and stability. These findings motivated the current review to provide a comprehensive summary of CD-based blood glucose sensors and their chemistry of glucose detection, efficiency, and accuracy. We categorize CD-based sensors into four groups based on their modification strategies, including CD-modified boronic acid, CD-modified mediators, CD-modified nanoparticles, and CD-modified functionalized polymers. These findings shed light on the potential of CD-based sensors as a promising tool for continuous GM in diabetes mellitus management.

Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin

Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD) have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid) have been evaluated. The sorption properties of granular activated carbon (GAC) were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (< 10¹ m²/g), CDI-X copolymers (< 10¹ m²/g), and granular activated carbon (GAC ~10³ m²/g). The sorption capacities for the copolymers sorbents are listed in descending order, as follows: GAC > CDI-3 copolymer ≈ MDI-3 copolymer. The sorption capacity for the aromatic adsorbates with each sorbent are listed in descending order, as follows: 2,4-dichlorophenol > 2,4-dichlorophenoxy acetic acid > pentachlorophenol. In general, the differences in the sorption properties of the copolymer sorbents with the chlorinated organics were related to the following factors: (i) surface area of the sorbent; (ii) CD content and accessibility; and (iii) and the chemical nature of the sorbent material.

Supramolecular assembly of cyclodextrin-based nanoparticles on solid surfaces for gene delivery

In this work, a new approach for surface-mediated gene delivery based on inclusion complex formation between the solid surface and delivery vehicles is presented. beta-Cyclodextrin (CD) molecules form high-affinity inclusion complexes with adamantane. This complexation ability was used to specifically immobilize beta-CD-modified poly(ethylenimine) (CD-PEI) nanoparticles on adamantane- (AD-) modified self-assembled monolayers. To investigate the nanoparticle/surface interaction, CD-PEI-based and PEI-based nanoparticles were passed through a surface plasmon resonance flow cell containing the monolayers. CD-PEI nanoparticles are specifically immobilized on the chip surface by cyclodextrin-adamantane inclusion complex formation. Minimal nanoparticle adsorption was detected with PEI-based nanoparticles or on control surfaces. Competition studies with free cyclodextrins reveal that the multivalent interactions between CD-PEI nanoparticles and the adamantane-modified surface results in significantly higher binding affinity than single cyclodextrin-adamantane complexes. Immobilized nanoparticles were characterized by atomic force microscopy and quantified by fluorescence assay. Thus, the ability of CD-PEI nanoparticles to form inclusion complexes can be exploited to attain specific, high-affinity loading of delivery vehicles onto solid surfaces.

Survey of the year 2005 commercial optical biosensor literature

We identified 1113 articles (103 reviews, 1010 primary research articles) published in 2005 that describe experiments performed using commercially available optical biosensors. While this number of publications is impressive, we find that the quality of the biosensor work in these articles is often pretty poor. It is a little disappointing that there appears to be only a small set of researchers who know how to properly perform, analyze, and present biosensor data. To help focus the field, we spotlight work published by 10 research groups that exemplify the quality of data one should expect to see from a biosensor experiment. Also, in an effort to raise awareness of the common problems in the biosensor field, we provide side-by-side examples of good and bad data sets from the 2005 literature.