Photopolymerization as a promising method to sense biorecognition events

Sustained release of 3D printed bupropion hydrochloride tablets bearing Braille imprints for the visually impaired

3D printing has been introduced as a novel approach for the design of personalized dosage forms and support patient groups with special needs that require additional assistance for enhanced medication adherence. In this study liquid crystal display (LCD) is introduced for the development of sustained release bupropion.HCl printed tablets. The optimization of printing hydrogel inks was combined with the display of Braille patterns on the tablet surface for blind or visually impaired patients. Due to the high printing accuracy, the Braille patterns could be verified by blind patients and provide the required information. Further characterization revealed the presence of BUP in amorphous state within the photopolymerized resins. The selection of poly(ethylene glycol) (PEG)-diacrylate (PEGDA) of different molecular weights and the presence of surfactants or solubilizers disrupted the resin photopolymerization, thus controlling the BUP dissolution rates. A small batch scale-up study demonstrated the capacity of LCD to print rapidly a notable number of tablets within 24 min.

Influence of PEGDA Molecular Weight and Concentration on the In Vitro Release of the Model Protein BSA-FITC from Photo Crosslinked Systems

Novel 3D printing techniques enable the development of medical devices with drug delivery systems that are tailored to the patient in terms of scaffold shape and the desired pharmaceutically active substance release. Gentle curing methods such as photopolymerization are also relevant for the incorporation of potent and sensitive drugs including proteins. However, retaining the pharmaceutical functions of proteins remains challenging due to the possible crosslinking between the functional groups of proteins, and the used photopolymers such as acrylates. In this work, the in vitro release of the model protein drug, albumin-fluorescein isothiocyanate conjugate (BSA-FITC) from differently composed, photopolymerized poly(ethylene) glycol diacrylate (PEGDA), an often employed, nontoxic, easily curable resin, was investigated. Different PEGDA concentrations in water (20, 30, and 40 wt %) and their different molecular masses (4000, 10,000, and 20,000 g/mol) were used to prepare a protein carrier with photopolymerization and molding. The viscosity measurements of photomonomer solutions revealed exponentially increasing values with increasing PEGDA concentration and molecular mass. Polymerized samples showed increasing medium uptake with an increasing molecular mass and decreasing uptake with increasing PEGDA content. Therefore, the modification of the inner network resulted in the most swollen samples (20 wt %) also releasing the highest amount of incorporated BSA-FITC for all PEGDA molecular masses.

Radical polymerization reactions for amplified biodetection signals

This review summarizes various radical polymerization chemistries for amplifying biodetection signals and compares them from the practical point of view.

Using photo-initiated polymerization reactions to detect molecular recognition

Radical polymerization reactions initiated by light can be used to provide signal amplification in molecular binding assays.