Development of a label-free, sensitive gold nanoparticles-poly(adenine) aptasensing platform for colorimetric determination of aflatoxin B1 in corn.

In this work, a sensitive colorimetric bioassay method based on a poly(adenine) aptamer (polyA apt) and gold nanoparticles (AuNPs) was developed for the determination of aflatoxin B1 (AFB1). The polyA apt, adsorbed on the AuNPs, especially can bind to the analyte while deterring non-specific interactions. This nano aptasensor uses cationic polymer poly(diallyl dimethyl ammonium chloride) (PDDA), as an aggregating agent, to aggregate gold nanoparticles.

Vancomycin and nisin-modified magnetic FeO@SiO nanostructures coated with chitosan to enhance antibacterial efficiency against methicillin resistant Staphylococcus aureus (MRSA) infection in a murine superficial wound model.

Background: The objective of this research was to prepare some FeO@SiO@Chitosan (CS) magnetic nanocomposites coupled with nisin, and vancomycin to evaluate their antibacterial efficacy under both in vitro and in vivo against the methicillin-resistant Staphylococcus. aureus (MRSA).

Methods: In this survey, the FeO@SiO magnetic nanoparticles (MNPs) were constructed as a core and covered the surface of MNPs via crosslinking CS by glutaraldehyde as a shell, then functionalized with vancomycin and nisin to enhance the inhibitory effects of nanoparticles (NPs).

On chip synthesis of a pH sensitive gefitinib anticancer drug nanocarrier based on chitosan/alginate natural polymers.

In this research, using a microfluidic chip, a nanocarrier for the anticancer drug gefitinib was synthesized. Chitosan and alginate natural polymers were utilized for the synthesis of the nanocarrier. The synthesis of the nanocarrier comprises the interaction of secondary amine functional groups of gefitinib molecules with carboxylate functional groups of alginate polymer to form the primary nucleus followed by the formation of the nanocarrier through the self-assembly of chitosan and alginate polymers on a fabricated microfluidic chip.

Preparation and characterisation of self-emulsifying drug delivery system (SEDDS) for enhancing oral bioavailability of metformin hydrochloride using hydrophobic ion pairing complexation.

Aim: The aim of this study was preparation of a self-emulsifying drug delivery system (SEEDS) containing metformin hydrochloride.

Methods: Hydrophobic ion paired complexes were prepared by electrostatic interaction between metformin and sodium lauryl sulphate (SLS). The nanodroplets were optimised using two-level full factorial methodology and their morphology were examined.

A novel label-free colorimetric polyA aptasensing approach based on cationic polymer and silver nanoparticles for detection of tobramycin in milk.

In this study, a novel colorimetric bioassay method was developed for the sensitive determination of tobramycin (TOB). To detect TOB, silver nanoparticles (AgNPs) were decorated with TOB-specific aptamers (apt), and positively charged poly diallyl dimethyl ammonium chloride (PDDA) was used. As long as tobramycin is not present in the assay system, PDDA can coalesce with the aptamer, and AgNPs would remain stable (λmax = 400 nm) in the dispersed system against PDDA-induced aggregation.

Nano optical and electrochemical sensors and biosensors for detection of narrow therapeutic index drugs.

For the first time, a comprehensive review is presented on the quantitative determination of narrow therapeutic index drugs (NTIDs) by nano optical and electrochemical sensors and biosensors. NTIDs have a narrow index between their effective doses and those at which they produce adverse toxic effects. Therefore, accurate determination of these drugs is very important for clinicians to provide a clear judgment about drug therapy for patients.

A novel label-free colorimetric aptasensor for sensitive determination of PSA biomarker using gold nanoparticles and a cationic polymer in human serum.

In this colorimetric assay for sensitive detection of prostate specific antigen (PSA) tumor marker, adsorbed non-thiolated poly-Adenine aptamer (polyA Apt) on the gold nanoparticles (AuNPs) surface was used. By incubating the AuNPs and the PSA specific aptamer prior to target addition, polyA Apt adsorbed on the gold nanoparticles and could bind the target while preventing non-specific interactions. Adsorbed polyA Apt on the AuNPs prevents aggregation of them by poly(diallyldimethylammoniumchloride) (PDDA).

Two colorimetric ampicillin sensing schemes based on the interaction of aptamers with gold nanoparticles.

Two kinds of aptasensors for ampicillin (AMP) are described. The assay strategies include the use of gold nanoparticles (AuNPs) that were modified with (a) a thiolated aptamer (T-Apt), and (b) a non-thiolated polyadenine aptamer (polyA Apt). The AuNPs and the aptamers were brought to interaction prior to addition of AMP.