Doxorubicin Loaded Poloxamer Thermosensitive Hydrogels: Chemical, Pharmacological and Biological Evaluation

Abstract

(1) Background: doxorubicin is a potent chemotherapeutic agent, but it has limitations regarding its side effects and therapy resistance. Hydrogels potentially deal with these problems, but several characterizations need to be optimized to better understand how hydrogel assisted chemotherapy works. Poloxamer 407 (P407) hydrogels were mixed with doxorubicin and physico-chemical, biological, and pharmacological characterizations were considered. (2) Methods: hydrogels were prepared by mixing P407 in PBS at 4 °C. Doxorubicin was added upon solutions became clear. Time-to-gelation, hydrogel morphology, and micelles were studied first. The effects of P407-doxorubicin were evaluated on MC-38 colon cancer cells. Furthermore, doxorubicin release was assessed and contrasted with non-invasive in vivo whole body fluorescence imaging. (3) Results: 25% P407 had favorable gelation properties with pore sizes of 30–180 µm. P407 micelles were approximately 5 nm in size. Doxorubicin was fully released in vitro from 25% P407 hydrogel within 120 h. Furthermore, P407 micelles strongly enhanced the anti-neoplastic effects of doxorubicin on MC-38 cells. In vivo fluorescence imaging revealed that hydrogels retained fluorescence signals at the injection site for 168 h. (4) Conclusions: non-invasive imaging showed how P407 gels retained drug at the injection site. Doxorubicin P407 micelles strongly enhanced the anti-tumor effects.

Enhanced Transdermal Delivery of Pranoprofen Using a Thermo-Reversible Hydrogel Loaded with Lipid Nanocarriers for the Treatment of Local Inflammation

“…The pH value of this formulation was 6.5, which is suitable for skin administration and suggests a non-irritating effect. Regarding the morphological structure (Figure 2), SEM micrographs of PF-NLCs-F127 hydrogel revealed the typical porous structure that characterizes Pluronic gels [29]. Moreover, PF-NLCs of nanometric size and spherical shape dispersed inside the hydrogel without showing aggregation (none was observed).…”

Stereomicroscope with Imaging Analysis: A Versatile Tool for Wetting, Gel Formation and Erosion Rate Determinations of Eutectic Effervescent Tablet

“…In this study, as observed under the stereomicroscope, the carbonation reaction of eutectic effervescent tablets gradually occurred upon immersion in the medium. This is explained by gelling capabilities of P407, which can retard the breakdown of the eutectic effervescent tablet [54]. For the results of mathematical model fitting, all formulations exhibited the tendencies of Peppas-Sahlin in which the R 2 values were close to 1.0.…”

Pre‐clinical and clinical applications of thermoreversible hydrogels in biomedical engineering: a review

“…192 Several poloxamers are commercially available, differing in composition and molar mass (MM). 34,[192][193][194] The most commonly used poloxamer in TRG-related studies is poloxamer 407 (Pluronic® F127, MM ≈ 12.6 kg mol −1 and EG 70 wt%), 6,[43][44][45][46][47][48][49][50][51][52][53][54][55][56]195,196 as this poloxamer gels at lower temperatures and concentrations compared to the other members of the family. 34 More specifically, it has been reported that poloxamer 407 gels at 12.6 w/v% in phosphate buffered saline (PBS), when purified appropriately, while gelation is not observed when the concentration is reduced to 11.6 w/v%.…”

“…without any polymer additives that would act as gelation modifiers, were applied in vivo have been reported in the literature. 6,[43][44][45][46][47][48][49][50][51][52][53][54][55][56]195,196 Most of the studies have used solutions of poloxamer 407 at 20 w/w% and higher, due to the higher stability and strength of the gel; however, a few studies have attempted the application at 15 w/w%. In TE, the gel was used to replace the nucleus pulposus, which acts as a shock absorber, in the intervertebral disc in dogs, and it was proven to be effective in resisting the strain applied for at least a period of 3 months.…”