Herein, a cost-effective and prompt approach to develop ionic material-based combination nanodrugs for cancer therapy is presented. A chemotherapeutic (phosphonium) cation and photodynamic therapeutic (porphyrin) anion are combined using a single step ion exchange reaction. Afterward, a nanomedicine is prepared from this ionic materials-based combination drug using a simplistic strategy of reprecipitation. Improved photophysical characteristics such as a slower nonradiative rate constant, an enhanced phosphorescence emission, a longer lifetime, and a bathochromic shift in absorbance spectra of porphyrin are observed in the presence of a chemotherapeutic countercation. The photodynamic therapeutic activity of nanomedicines is investigated by measuring the singlet oxygen quantum yield using two probes. As compared to the parent porphyrin compound, the synthesized combination material showed a 2-fold increase in the reactive oxygen species quantum yield, due to inhibition of face-toface aggregation of porphyrin units in the presence of bulky chemotherapeutic ions. The dark cytotoxicity of combination therapy nanomedicines in the MCF-7 (cancerous breast) cell line is also increased as compared to their corresponding parent compounds in vitro. This is due to the high cellular uptake of the combination nanomedicines as compared to that of the free drug. Further, selective toxicity toward cancer cells was acquired by functionalizing nanomedicine with folic acid followed by incubation with MCF-7 and MCF-10A (noncancerous breast). Light toxicity experiments indicate that the synthesized ionic nanomedicine shows a greater cell death than either parent drug due to the improved photophysical properties and effective combination effect. This facile and economical strategy can easily be utilized in the future to develop many other combination ionic nanomedicines with improved photodynamics.

Combination nanodrugs are promising therapeutic agents for cancer treatment. However, they often require the use of complex nanovehicles for transportation into the tumor site. Herein, a new class of carrier-free...

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Herein, metal-free heteroatom doped carbon-based materials are being reviewed for supercapacitor and energy applications. Most of these low-cost materials considered are also derived from renewable resources. Various forms of carbon that have been employed for supercapacitor applications are described in detail, and advantages as well as disadvantages of each form are presented. Different methodologies that are being used to develop these materials are also discussed. To increase the specific capacitance, carbon-based materials are often doped with different elements. The role of doping elements on the performance of supercapacitors has been critically reviewed. It has been demonstrated that a higher content of doping elements significantly improves the supercapacitor behavior of carbon compounds. In order to attain a high percentage of elemental doping, precursors with variable ratios as well as simple modifications in the syntheses scheme have been employed. Significance of carbon-based materials doped with one and more than one heteroatom have also been presented. In addition to doping elements, other factors which play a key role in enhancing the specific capacitance values such as surface area, morphology, pore size electrolyte, and presence of functional groups on the surface of carbon-based supercapacitor materials have also been summarized.

In this study, we have evaluated the effect of potassium hydroxide (KOH) on the energy storage performance of metal-free carbon-based materials prepared from molasses. Molasses are a renewable-resource biomass and economical by-product of sugar refinement, used here as a carbon precursor. Two co-doped carbon materials using molasses were synthesized via a time and cost-efficient microwave carbonization process, with ammonium polyphosphate as a phosphorus and nitrogen doping agent. The phosphorus and nitrogen co-doped carbon (PNDC) samples were prepared in the presence and absence of a chemical activating agent (KOH), to study the role of chemical activation on PNDCs. Physical characterizations were performed to gain insight into the composition, pore size and topographical data of each material. Electrochemical characterization via cyclic voltammetry in 1 M sulfuric acid (H2SO4) as well as in 6 M KOH as electrolytes, revealed high current density and specific capacitance for the chemically activated material (PNDC2) compared to one without chemical activation (PNDC1). The capacitance value of 244 F/g in KOH electrolyte was obtained with PNDC2. It is concluded that addition of KOH prior to carbonization increases the surface functionality, which significantly enhances the electrochemical properties of the PNDC material such as current density, stability, and specific capacitance.