Validated LC-MS/MS method for simultaneous determination of doxorubicin and curcumin in polymeric micelles in subcellular compartments of MCF-7/Adr cells by protein precipitation-ultrasonic breaking method.

A specific and sensitive LC-MS/MS with protein precipitation- ultrasonic breaking method has been developed and validated for simultaneous determination of doxorubicin (DOX) and curcumin (Cur) in DOX and Cur co-loaded hyaluronic acid-vitamin E succinatemicelles [(DOX + Cur)-polymeric micelles (PMs)] in subcellular compartments of resistant MCF-7/Adr cells. Sequential extraction of four subcellular protein fractions (cytosolic, membrane/organelle, nucleic and cytoskeleton) was performed directly from MCF-7/Adr cells after incubation with (DOX + Cur)-PMs. An ultrasonic breaking-methanol precipitation method was used for extraction of the fractions, and the micelle breaking efficiency with methanol was 98.1 and 97.6% for DOX and Cur, respectively. The analytes were analyzed using positive electrospray ionization coupled with multiple reaction monitoring. The calibration curves were linear over a concentration range of 0.5-400 ng/mL for DOX and 2-2000 ng/mL for Cur, and the recovery for the two analytes were >85% with negligible matrix effect. The intra-day and inter-day precision was <10.80% and relative error was within ±7.70%. The developed method was successfully applied for subcellular determination of DOX and Cur in MCF-7/Adr cells. Moreover, Cur and (DOX + Cur)-PMs had a marked promoting effect on the distribution of DOX in the nucleic protein fraction.

[Preparation characterization and antitumor activity in vitro of berberine hydrochloride polymeric micelles].

With polyethylene glycol vitamin E succinate (TPGS) as the carrier materials, and berberine hydrochloride ( BER) as model drug, we formed berberine hydrochloride (BER) -loaded TPGS nanomicells (BER-PMs) using filming-rehydration method to improve its solubility and in vitro anti-tumor effect. The transmission electron microscope (TEM) was used to observe the particle appearance; particle detector was used to detect the diameter and Zeta potential; and ultracentrifugation was utilized to determine the encapsulation efficiency (EE) and drug-loading (DD); dynamic dialysis method was used to study the in vitro release behavior of BER-PMs, and the anti-tumor activity against MCF-7 cells was determined by MTT method. Results showed that the average particle size of BER-PMs was (12.45 ± 1.46) nm; particle size was uniform and spherical; drug loading and encapsulation efficiency were (5.7 ± 0.22)% and (95.67 ± 5.35)%, respectively. Zeta potential was (-1.12 ± 0.23) mV; release rate within 24 h was 37.20% and 41.14% respectively in pH 7.4 and pH 6.5 phosphate buffer in vitro; compared with BER, BER-PMs can significantly inhibit MCF-7 cell proliferation (P < 0.05), promote cell apoptosis and improve the anti-tumor activity of BER in vitro. Therefore, the formed berberine hydrochloride micelle can more effectively promote the apoptosis of MCF-7 cell, and improve the drug's in vitro anti-tumor effect.

Synergistically Improved Anti-tumor Efficacy by Co-delivery Doxorubicin and Curcumin Polymeric Micelles.

P-gp mediated drug efflux has been recognized as a major obstacle limiting the success of cancer chemotherapy. To overcome this issue, doxorubicin (DOX) and curcumin (Cur; P-gp inhibitor and apoptosis inhibitor) co-encapsulated pegylated polymeric micelles ((DOX+Cur)-PMs) were designed, prepared and characterized to simultaneously deliver chemotherapeutic drug and multidrug resistance (MDR) modulator to tumor sites. The (DOX+Cur)-PMs were spherical nano-size particle, with a loading content of 6.83%, and high colloidal stability. Co-delivery micelles exhibited excellent cytotoxicity by reversing MDR, promoting cellular uptake and enhancing cellular apoptosis in MCF7/Adr cells. The tumor growth inhibitory effect of (DOX+Cur)-PMs in 4T1-bearing mice was more effective compared with the combination solution of DOX and Cur and even DOX-PMs. In conclusion, simultaneous delivery of DOX and Cur by (DOX+Cur)-PMs has been demonstrated to be a promising approach for overcoming MDR and improving antitumor efficacy.