A unique "turn-on" fluorescence signalling strategy for highly specific detection of ascorbic acid using carbon dots as sensing probe.

Carbon dots (CDs) that showed strong blue fluorescence were successfully synthesised from sodium alginate via furnace pyrolysis. The single step pyrolytic synthesis was simple to perform while yielded CDs with high photostability, good water solubility and minimum by-products. In order to design the probe with "turn-on" sensing capability, the CDs were screened against a series of metal cations to first "turn-off" the fluorescence.

One-pot synthesis of carbon dots using two different acids and their respective unique photoluminescence property.

Carbon dots, a new class of nanomaterial with unique optical property and have great potential in various applications. This work demonstrated the possibility of tuning the emission wavelength of carbon dots by simply changing the acid type used during synthesis. In particular, sulfuric and phosphoric acids and a mixture of the two were used to carbonize the same starting precursor, sucrose.

Integrated miniature fluorescent probe to leverage the sensing potential of ZnO quantum dots for the detection of copper (II) ions.

Quantum dots are fluorescent semiconductor nanoparticles that can be utilised for sensing applications. This paper evaluates the ability to leverage their analytical potential using an integrated fluorescent sensing probe that is portable, cost effective and simple to handle. ZnO quantum dots were prepared using the simple sol-gel hydrolysis method at ambient conditions and found to be significantly and specifically quenched by copper (II) ions.

Synthesis of fluorescent carbon dots via simple acid hydrolysis of bovine serum albumin and its potential as sensitive sensing probe for lead (II) ions.

Carbon dots have great potential to be utilised as an optical sensing probe due to its unique photoluminescence and less toxic properties. This work reports a simple and novel synthesis method of carbon dots via direct acid hydrolysis of bovine serum albumin protein in a one-pot approach. Optimisation of the important synthetic parameters has been performed which consists of temperature effect, acid to protein ratio and kinetics of reaction.

Molecularly imprinted polymers as optical sensing receptors: correlation between analytical signals and binding isotherms.

Despite the increasing number of usage of molecularly imprinted polymers (MIPs) in optical sensor application, the correlation between the analytical signals and the binding isotherms has yet to be fully understood. This work investigates the relationship between the signals generated from MIPs sensors to its respective binding affinity variables generated using binding isotherm models. Two different systems based on the imprinting of metal ion and organic compound have been selected for the study, which employed reflectance and fluorescence sensing schemes, respectively.

An enzyme-modulated oxygen-producing micro-system for regenerative therapeutics.

This study suggests the idea of treating oxygen as a drug in a biological environment and demonstrates that it will exhibit a dosage-dependent trend. To accomplish this, a micro-system was fabricated, having hydrogen peroxide as the oxygen-generating source, which was decomposed using catalase, a common enzyme found in nearly all living organisms. The relevance of the proposed micro-system was justified using cell viability assays under well-controlled and fixed conditions.

Novel microencapsulation of potential drugs with low molecular weight and high hydrophilicity: hydrogen peroxide as a candidate compound.

Microencapsulation of drugs into solid biodegradable polymeric microspheres via solvent evaporation technique remains challenging especially with those having low molecular weight and high hydrophilicity nature. This paper presents an efficient encapsulation protocol for this group of drugs, demonstrated using hydrogen peroxide as a model compound that is encapsulated into poly(lactic-co-glycolic acid) microspheres. Hydrogen peroxide can be employed as antiseptic agent or its decomposed form into oxygen can be useful in various pharmaceutical applications.

Fluorescence sensor using a molecularly imprinted polymer as a recognition receptor for the detection of aluminium ions in aqueous media.

This paper describes the investigation of a molecularly imprinted polymer (MIP) as a sensing receptor for Al(3+) ion detection by using an optical approach. Al(3+) ion was adopted as the template molecule and 8-hydroxyquinoline sulfonic acid ligand as the fluorescence tag. The polymer was synthesised using acrylamide as monomer, 2-hydroxyethyl methacrylate as co-monomer and ethylene glycol dimethracylate as cross-linker.