Cooperation effect of 4-vinylbenzeneboronic acid/methacrylic acid on affinity of capecitabine imprinted polymer for drug carrier

A selective dual-signal electrochemical paper-based device using imprinted sensors for voltammetric and impedance analysis of 4-NQO and carcinoembryonic antigen (CEA)

BACKGROUND

Carcinoembryonic Antigen (CEA) and 4-nitroquinoline-N-oxide (4-NQO) are cancer markers that play a crucial role in tumor risk assessment and early cancer diagnosis. Therefore, it is in demand to develop a fast, accurate, simple, and cost-effective method to detect these cancer markers for quick and early stage-cancer diagnosis and treatment.

RESULTS

Herein, we report a dual signaling approach for direct and indirect signal transduction of cancer biomarker binding on molecularly imprinted-electrodes integrated on an ePAD, enabling sensitive and selective quantitative analysis of 4-NQO and CEA. Multiple test zones on a single device based on artificial recognition sites using core-shell Cu-MOF@MIP were developed to create a selective "Dual-signal-ePAD". An effective and facile imprinting method on a Cu-MOF surface based on the synthesized of 4-VPBA/MAA/TRIM polymer. It resulted in a novel MIP useable as a high-performance sensing tool for the ultrasensitive and specific quantification of the target cancer biomarkers. Multiple tests consisted of voltammetric analysis of 4-NQO via oxidation of the analyte on a WE1, and impedance analysis of CEA via the molecular interaction with the imprinted WE2.

SIGNIFICANCE

The proposed device provides enhanced electrochemical signal amplification due to its high conductivity, electrocatalytic activity, and the target-specific recognition sites for accurate determination of 4-NQO and CEA targets. The Dual-signal-ePAD exhibits good voltammetric and EIS response, oxidation currents of 4-NQO at -0.06 V and RCT of CEA, resulting in high selectivity and sensitivity with a linear response range covering the concentration range of clinical interest for both analytes. Dual-signal ePAD is a good candidate for clinical screening and POCT.

Artificial antibody-antigen-directed immobilization of α-amylase to hydrolyze starch for cascade reduction of 2-nitro-4-methylphenol to 2-amino-4-methylphenol

Nitrophenol is a hazardous substance that poses a threat to the environment and human health, and its treatment has attracted widespread attention. The purpose of this study is to establish an environmentally friendly α-amylase system for the hydrolysis of starch to reduce nitrophenol to aminophenol through cascade reactions. The α-amylase system was obtained through artificial antibody-antigen-directed immobilization, including the synthesis of artificial antibodies, synthesis of artificial antigens, and affinity assembly. In this process, catechol and protocatechuic aldehyde were used to prepare artificial antibodies and artificial antigens respectively through polymerization and Schiff base reactions. Then, artificial antibodies captured the catechol in the artificial antigen structure to form immobilized α-amylases. Compared with free α-amylase, the immobilized α-amylase showed a good reusability and excellent regenerative ability. Subsequently, the immobilized α-amylase were used in the reaction of catalyzing starch hydrolysis to synthesize 2-amino-4-methylphenol, and the yield of 2-amino-4-methylphenol was 58.88 ± 0.19 %. After 5 consecutive catalytic reactions, a yield of 47.61 ± 1.27 % can still be achieved.

Design of pH-responsive molecularly imprinted polymer as a carrier for controlled and sustainable capecitabine release

A molecularly imprinting polymer (MIP) carrier with pH-responsivity was designed to construct a drug delivery system (DDS) focusing on controlled and sustainable capecitabine (CAPE) release. The pH-responsive characteristic was achieved by the functionalization of SiO2 substrate with 4-formylphenylboronic acid, accompanied by the introduction of fluorescein isothiocyanate for the visualization of the intracellular localization of the nanocarrier. Experimental results indicated that CAPE was adsorbed onto the drug carrier with satisfactory encapsulation efficiency. The controlled release of CAPE was realized based on the break of borate ester bonds between -B(OH)2 and cis-diols in the weakly acidic environment. Density functional theory computations were conducted to investigate the adsorption/release mechanism. Moreover, in vitro experiments confirmed the good biocompatibility and ideal inhibition efficiency of the developed DDS. The MIP can act as an eligible carrier and exhibits the great potential in practical applications for tumor treatment.

In Vivo Applications of Molecularly Imprinted Polymers for Drug Delivery: A Pharmaceutical Perspective

Molecularly imprinted polymers (MIPs) have been proven to be a promising candidate for drug delivery systems (DDS) due to their ability to provide a sustained and controlled drug release, making them useful for treating a wide range of medical conditions. MIP-based DDS offer many advantages, including the administration of a smaller drug doses, due to the higher drug payload or targeted delivery, resulting in fewer side effects, as well as the possibility of attaining high concentrations of the drug in the targeted tissues. Whether designed as drug reservoirs or targeted DDS, MIPs are of great value to drug delivery as conventional drug formulations can be redesigned as DDS to overcome the active pharmaceutical ingredient's (APIs) poor bioavailability, toxic effects, or other shortcomings that previously made them less efficient or unsuitable for therapy. Therefore, MIP design could be a promising alternative to the challenging research and development of new lead compounds. Research on MIPs is primarily conducted from a material science perspective, which often overlooks some of their key pharmaceutical requirements. In this review, we emphasize the specific features that make MIPs suitable for clinical use, from both a material science and a biopharmaceutical perspective.

Chitosan-glucuronic acid conjugate coated mesoporous silica nanoparticles: A smart pH-responsive and receptor-targeted system for colorectal cancer therapy

Glycosylated pH-sensitive mesoporous silica nanoparticles (MSNs) of capecitabine (CAP) were developed for targeting colorectal cancer. The MSNs possessed an average pore diameter of 8.12 ± 0.43 nm, pore volume of 0.73 ± 0.21 cm3/g, and particle size of 245.24 ± 5.75 nm. A high loading of 180.51 ± 5.23 mg/g attributed to the larger pore volume was observed. The surface of the drug-loaded MSNs were capped with chitosan-glucuronic acid (CHS-GCA) conjugate to combine two strategies viz. pH-sensitive, and lectin receptor mediated uptake. In vitro studies demonstrated a pH-sensitive and controlled release of CAP which was further enhanced in the presence of rat caecal content. Higher uptake of the (CAP-MSN)CHS-GCA was observed in HCT 116 cell lines. The glycosylated nanoparticles revealed reduction in the tumors, aberrant crypt foci, dysplasia and inflammation, and alleviation in the toxic features. This illustrated that the nanoparticles showed promising antitumor efficacy with reduced toxicity and may be used as a effective carrier against cancer.