Synthesis and Characterization of Dual-Sensitive Fluorescent Nanogels for Enhancing Drug Delivery and Tracking Intracellular Drug Delivery

Abstract

Here, dual-sensitive fluorescent branched alginate-polyethyleneimine copolymer (bAPSC) nanogels were synthesized from thiolated alginate and stearoyl-derivatized branched polyethyleneimine. The formation of bAPSC conjugates was confirmed through proton nuclear magnetic resonance and Fourier transform infrared spectroscopy, whereas dynamic light scattering was used to measure the particle size and ζ potential of the nanogels. The fluorescent properties of the nanogels were confirmed through fluorescent spectroscopy and microscopy. In addition to the excitation-dependent fluorescence behavior, the fluorescence emission intensity of bAPSC was altered by both pH and γ-irradiation. This intensity was higher at a lower pH than at a higher pH, and it slightly decreased after γ-irradiation. The drug loading and encapsulation efficiency of bAPSC were 25.9% and 11.2%, respectively. An in vitro drug release study revealed that the synthesized nanogels release their doxorubicin (Dox) contents in a time-dependent manner, and the drug release was higher after 96 h of incubation. Approximately 43.74% and 88.36% of Dox was released after 96 h of incubation at pH 5.5 in the absence and presence of glutathione (GSH), respectively. However, relatively lower drug release, approximately 21.6% and 16%, was observed in the presence and absence of GSH at pH 7.4, respectively. Fluorescence microscopy confirmed that Dox-loaded bAPSC nanogels were internalized by HeLa cells, and drug distribution was easily tracked using fluorescent materials without additional probing agents. Moreover, cellular cytotoxicity and hemolysis results revealed less cytotoxicity and hemocompatibility of the synthesized nanogels, confirming that they are the most favorable alternative drug carriers for drug delivery systems.

Mixed Lanthanide Oxide Nanoparticles Coated with Alginate-Polydopamine as Multifunctional Nanovehicles for Dual Modality: Targeted Imaging and Chemotherapy

“…At each interval time, 3 mL of the released medium was collected and the absorbance was measured at 481 nm. Moreover, to keep the volume in the dialysis system constant, an equal amount of fresh buffer solution was replenished continuously according to previous protocols. , The amount of DOX released was compared with that of a pre-established calibration curve. The measurement was performed three times, and the cumulative release was analyzed based on the following formula: …”

“…Moreover, to keep the volume in the dialysis system constant, an equal amount of fresh buffer solution was replenished continuously according to previous protocols. 62,63 The amount of DOX released was compared with that of a pre-established calibration curve. The measurement was performed three times, and the cumulative release was analyzed based on the following formula: cumulative release (%) the concentration of drug release the concentration of drug load 100 = × (4)…”

Fluorescent Submicron-Sized Poly(heptafluoro-n-butyl methacrylate) Particles with Long-Term Stability

“…All measurements were performed at 20 ± 0.1 • C. The light scattering autocorrelation functions were obtained for scattering angles between 20 • and 150 • with an angular step of 5 • . The diffusion coefficients were obtained directly from the autocorrelation functions by using CONTIN algorithm for multiexponential decay analysis [25] built into the ALV-Correlator software (version 3.0).…”

“…Authors [24] reported that spectroscopic characteristics of dye-doped silica nanoparticles indicate a much higher photostability and brightness in comparison to the nanoparticles with free uncoupled dyes. As an alternative to solid fluorescent NPs, alginate gel-based systems were proposed [25].…”

Organic Fluorescent Dye-based Nanomaterials: Advances in the Rational Design for Imaging and Sensing Applications

“…As a branched polymer, PEI has been shown as an efficient base for nanogels synthesis that can be used for drug delivery. Alginate copolymer with hydrophobically modified PEI was shown to readily encapsulate doxorubicin, and the release is dependent on the environment pH and redox nature [58]. The obtained nanogels are also fluorescent, which adds another function of tracking the drug delivery.…”