Magneto-conducting multifunctional Janus microbots for intracellular delivery of biomolecules.

Although several advances have been made in the field of medicine during the last few decades, yet targeted delivery of biomolecules is still a significant challenge. Thus, the present study illustrates the fabrication of dual nature magneto-conducting Fe3 O4 -SU8 derived carbon-based Janus microbots that could deliver biomolecules efficiently inside cells. These microsystems possess dual properties, that is, the half part is magneto-conducting, and another half is only conducting for sufficing the therapeutic payloads efficiently under electromagnetic stimulations. These microbots are intrinsically fluorescent, which can help to trace them intracellularly without using any dye. UV photolithography was employed to design these low aspect ratio microbots (feature size âˆ¼2.5 µm diameter and 3.7 µm length) for attaining better control over locomotion with minimum magnetic field intensity. Interestingly, Janus microbots achieved a higher speed in the electric field (44 µm/s) as compared to the magnetic field (18 µm/s). Moreover, in vitro studies show a higher microbots uptake by HeLa cells in the presence of an external electric field as compared to without electrical field stimulation.

Magnetic nanofibers based bandage for skin cancer treatment: a non-invasive hyperthermia therapy.

BACKGROUND: The treatment of non-melanoma skin cancer and deadliest malignant melanoma skin cancer are the fifth and ninth most expensive treatments in Medicare, respectively. Moreover, the recurrence of cancer after currently available therapies, that is, surgery or radiotherapy, reduces the patient's life expectancy. AIMS: In view of this, we fabricated magnetic nanofibrous mat-based bandage to treat skin cancer non-invasively using an external alternating current (AC) magnetic field induced hyperthermia. METHODS: The Fe3 O4 nanoparticles incorporated polycaprolactone (PCL) fibers based bandages were fabricated using the electrospinning technique. The efficacy of the bandage was investigated in vitro using parental/doxorubicin hydrochloride (Dox)-resistant HeLa cells and in vivo using BALB/c mouse model in the presence of an external AC magnetic field (AMF). RESULTS: The PCL-Fe3 O4 fibrous mat-based bandages dissipate heat energy locally on the application of an external AMF and increase the surrounding temperature in a controlled way up to 45°C in a few mins. The in vitro study confirms the elevated temperature could kill parental and Dox-resistant HeLa cells significantly. As the activity of Dox enhanced at a higher temperatures, more than 85% of parental HeLa cells were dead when cells incubated with Dox contained fibrous mat in the presence of AMF for 10 minutes. Further, we confirm the full recovery of chemically induced skin tumors on BALB/c mice within a month after five hyperthermic doses for 15 minutes. Also, there was no sign of inflammation and recurrence of cancer post-therapy. CONCLUSION: The present study confirms the PCL-Fe3 O4 nanofibrous based bandages are unique and compelling to treat skin cancer.

A Composite of Hyaluronic Acid-Modified Graphene Oxide and Iron Oxide Nanoparticles for Targeted Drug Delivery and Magnetothermal Therapy.

Graphene oxide (GO) nanoparticles have been developed for a variety of biomedical applications as a number of different therapeutic modalities may be added onto them. Here, we report the development and testing of such a multifunctional GO nanoparticle platform that contains a grafted cell-targeting functionality, active pharmaceutical ingredients, and particulates that enable the use of magnetothermal therapy. Specifically, we demonstrate the ability to covalently attach hyaluronic acid (HA) onto GO, and the resultant nanoparticulates (GO-HA) exhibited low inherent toxicity toward two different breast cancer cell lines, BT-474 and MDA-MB-231. Doxorubicin (Dox) and paclitaxel (Ptx) were successfully loaded onto GO-HA with high and moderate efficiencies, respectively. A GO-HA-Dox/Ptx system was significantly better than the GO-Dox/Ptx system at specifically killing CD44-expressing MDA-MB-231 cells but not BT-474 cells that do not express CD44. Further, modified iron oxide nanoparticles were loaded onto the GO-HA-Dox system, enabling the use of magnetic hyperthermia. Hyperthermia in combination with Dox treatment through the GO-HA system showed significantly better performance in reducing viable tumor cell numbers when compared to the individual systems. In summary, we showcase a multifunctional GO nanoparticle system that demonstrates improved efficacy in killing tumor cells.

Magnetic hyperthermia adjunctive therapy for fungi: in vitro studies against Candida albicans.

The poor penetration of anti-fungal agents into the cornea through the intact epithelium layer makes it difficult to treat acute fungal corneal infections. Herein, we developed Amphotret (amphotericin B) antifungal drug contained polycaprolactone-Fe3O4 (PCL-FO) magnetic nanofibers (MNFs) using the electrospinning technique. These MNFs generate heat in the presence of AC magnetic field (AMF) and release drug upon heating. MNFs were compatible with human mesenchymal stem cells (hMSCs) and HeLa cells, which exhibited unaltered proliferation, ruling out any toxicity from the systems. Hyperthermia induced via MNFs from 42 °C to 50 °C compromised the viability of Candida albicans cells. Further, the efficacy of the systems was increased in the presence of both heat and drug simultaneously in vitro, leading to near 100% loss in viability of C. albicans cells at 50 °C with simultaneous drug release from MNFs. Thus, we propose magnetic hyperthermia as adjunctive therapy for fungal keratitis.