Essential oils are easy to cause oxidative damage, chemical transformation or polymerization, and have some intrinsic problems, such as instability, low water solubility and low bioavailability, which restrict their application in the fields of product development. Nanostructured lipid carriers(NLCs) can overcome some of the restrictions of other colloidal carriers, such as emulsions, liposomes, polymer nanoparticles and solid lipid nanoparticles. NLC is an efficient and stable delivery system for bioactive substances. With unique lipid properties(mixture of solid and liquid lipid), it can overcome the disadvantages of essential oils and protect them from adverse environments, thus improving the stability, bioavailability and safety of essential oils, and achieve sustained release and controlled release. In EOs-NLCs system, essential oils, as special liquid lipid with biological activities and medicinal properties, can fully play the role of medicine-adjuvant integration by changing the structural characteristics of mixed lipid. Based on the development of nanocarriers system, this paper introduces the composition and structural characteristics of EOs-NLCs, and clarifies how to improve the stability of essential oils based on the effects of NLCs on physical and chemical properties, physical stability and release of active components of essential oils. In addition, it also introduces the application of the system in the fields of pharmaceutical, food, cosmetics and skin care products. This review aims to provide some references for improving the stability of essential oils and their applications by using NLCs.
Drug Carriers ; Emulsions ; Lipids ; Liposomes ; Nanostructures ; Oils, Volatile ; Particle Size

Liposome is an ideal drug carrier with many advantages such as excellent biocompatibility, non-immunogenicity, and easy functionalization, and has been used for the clinical treatment of many diseases including tumors. For the treatment of tumors, liposome has some passive targeting capability, but the passive targeting effect alone is very limited in improving the drug enrichment in tumor tissues, and active targeting is an effective strategy to improve the drug enrichment. Therefore, active targeting liposome drug-carriers have been extensively studied for decades. In this paper, we review the research progresses on active targeting liposome drug-carriers based on the specific binding of the carriers to the surface of tumor cells, and summarize the opportunities, challenges and future prospects in this field.
Drug Carriers/therapeutic use* ; Drug Delivery Systems ; Humans ; Liposomes/therapeutic use* ; Neoplasms/drug therapy*

Liposomes and nanoparticles have been used as drug carriers to increase solubility, prolong drug duration in vivo, target drug delivery, reduce toxicity and combat multi-drug resistance. With major advances in the preparation techniques, preparation material, and surface modifiers in recent years, liposomes and nanoparticles delivery systems have achieved success in fields including cancer therapy, overcoming biological barriers, and biological drugs and vaccine carriage.
Drug Carriers ; Drug Delivery Systems ; methods ; Humans ; Liposomes ; Nanoparticles ; Vaccines ; administration & dosage ; chemistry

To develop different methods for determining siRNA content and the entrapment efficiency of siRNA loaded liposomes, SYBR Gold electrophoresis method and Ribogreen fluorospectrophotometry method were used respectively. SYBR Gold electrophoresis method has a good linear relation in a range at 0.2-2.0 micromol x L(-1) (R = 0.9930), and the recovery at the high, middle and low concentrations were 96.35%, 96.92%, and 100.74%, respectively (n = 3). The intra-day and inter-day RSD were far below 5% (n = 5). Ribogreen fluorospectrophotometry method has a good linear relation in a range at 10-50 nmol x L(-1) (R = 0.9971), and the recovery at the high, middle and low concentrations were 98.22%, 99.88% and 99.64%, respectively (n = 3). The intra-day and inter-day RSD were far below 5% (n = 5). The content and the entrapment efficiency of three batches of siRNA cationic liposomes were 98.52%, 97.85% and 99.20%, 96.45%, respectively, with these two methods. And there is no significant difference by ANOVA. Both of the two methods are accurate, sensitive, convenient method for determination of the siRNA content and the entrapment efficiency of siRNA loaded cationic liposomes.
Drug Carriers ; Drug Delivery Systems ; Electrophoresis ; Liposomes ; chemistry ; RNA, Small Interfering ; analysis ; Spectrometry, Fluorescence

To establish an HPLC method for determining components in monocrotalinum liposomes. The results showed a good linear relationship in monocrotalinum liposomes within the concentration range between 1.6-102.4 mg x L(-1) (r = 0.999 8), with RSDs of intra-day precision, inter-day precision, stability and reproducibility of 0.61%, 0.92%, 1.7%, 1.6%, respectively. The recovery rate of monocrotaline was (99.96 +/- 0.50)%. These data indicated that the HPLC method could accurately determine components in monocrotalinum liposomes. Meanwhile, the microcolumn centrifugation method was established to determine the entrapment efficiency of components in monocrotalinum liposomes. As a result, the recovery rate and the blank liposome recovery of free components were (94.44 +/- 0.77)%, (95.86 +/- 0.68 )%, respectively. According to the parallel determination of the entrapment efficiency of three monocrotaline liposomes, their RSD was 4.0%. The data indicated that the microcolumn centrifugation method was an accurate and feasible method for determining the entrapment efficiency of monocrotaline liposomes.
Chromatography, High Pressure Liquid ; methods ; Drug Carriers ; chemistry ; Drug Compounding ; Liposomes ; chemistry ; Monocrotaline ; chemistry

The optimal prescription of tanshinone Ⅱ_A(TSN)-glycyrrhetinic acid(GA) solid lipid nanoparticles(GT-SLNs) was explored and evaluated in vivo and in vitro, and its effect on acne after oral administration was investigated. The preparation processing and prescription were optimized and verified by single factor and response surface methodology. The in vitro release of GA and TSN in GT-SLNs was determined by ultra-performance liquid chromatography(UPLC). The effect of GT-SLNs on acne was investigated by the levels of sex hormones in mice, ear swelling model, and tissue changes in sebaceous glands, and the pharmacokinetics was evaluated. The 24-hour cumulative release rates of GA and TSN in SLNs were 65.87%±5.63% and 36.13%±2.31% respectively. After oral administration of GT-SLNs and the mixture of GA and TSN(GT-Mix), the AUC_(0-t) and AUC_(0-∞) of TSN in GT-SLNs were 1.98 times and 4.77 times those in the GT-Mix group, respectively, and the peak concentration of TSN in the GT-SLNs group was 17.2 times that in the GT-Mix group. After intragastric administration of GT-SLNs, the serum levels of testosterone(T) and the ratio of testosterone to estradiol(T/E2) in the GT-SLNs group significantly declined, and the sebaceous glands of mice were atrophied to a certain extent. The results demonstrated that obtained GT-SLNs with good encapsulation efficiency and uniform particle size could promote the release of GA and TSN. GT-SLNs displayed therapeutic efficacy on acne manifested by androgen increase, abnormal sebaceous gland secretion, and inflammatory damage.
Abietanes ; Acne Vulgaris/drug therapy* ; Animals ; Drug Carriers ; Glycyrrhetinic Acid ; Liposomes ; Mice ; Nanoparticles ; Particle Size ; Testosterone

Currently, the first-line drugs for invasive fungal infections (IFI), such as amphotericin B, fluconazole and itraconazole, have drawbacks including poor water solubility, low bioavailability, and severe side effects. Using drug delivery systems is a promising strategy to improve the efficacy and safety of traditional antifungal therapy. Synthetic and biomimetic carriers have greatly facilitated the development of targeted delivery systems for antifungal drugs. Synthetic carrier drug delivery systems, such as liposomes, nanoparticles, polymer micelles, and microspheres, can improve the physicochemical properties of antifungal drugs, prolong their circulation time, enhance targeting capabilities, and reduce toxic side effects. Cell membrane biomimetic drug delivery systems, such as macrophage or red blood cell membrane-coated drug delivery systems, retain the membrane structure of somatic cells and confer various biological functions and specific targeting abilities to the loaded antifungal drugs, exhibiting better biocompatibility and lower toxicity. This article reviews the development of antifungal drug delivery systems and their application in the treatment of IFI, and also discusses the prospects of novel biomimetic carriers in antifungal drug delivery.
Antifungal Agents/therapeutic use* ; Drug Delivery Systems ; Amphotericin B/therapeutic use* ; Liposomes/chemistry* ; Nanoparticles ; Drug Carriers

OBJECTIVETo prepare the novel liposomes composed of hydrogenated soybean phosphatidylcholine (HSPC) and soybean phosphatidylcholine (SPC) containing the total alkaloids from seed of Strychnos nux-vomica, and to compare the pharmaceutical properties of the novel liposomes with the corresponding HSPC or SPC liposomes.

METHODThe total alkaloids were extracted from seeds of S. nux-vomica. and further purified. Novel liposomes containing the total alkaloids were prepared by ammonium sulfate transmembrane gradients and stealth liposome technique. Pharmaceutical properties such as encapsulation efficiency (EE), size, zeta potential and drug release profile of novel liposomes and corresponding HSPC or SPC liposomes were compared intensively.

RESULTFor novel liposomes, HSPC-SPC (1:3) was the best ratio which has the highest EE. At the drug/lipid weight ratio of 1:6, the EE of novel, SPC and HSPC liposomes were (73.6 +/- 2.9)%, (62.9 +/- 1.8)% and (54.7 +/- 1.0)% (n = 3), respectively. Compared with the corresponding SPC or HSPC liposomes, the size of novel liposomes was obviously decreased but the zeta potential was not different. The results of drug release showed that the novel liposomes were more stable than the SPC liposomes in the presence of rat plasma

CONCLUSIONTaken together, high encapsulation efficiency improved stability in blood, and relative low price of phospholipids of the novel liposomes, indicate that the novel liposomes may act as promising carriers for anti-tumor traditional Chinese medicine.

Alkaloids ; chemistry ; Animals ; Drug Carriers ; chemistry ; Liposomes ; chemistry ; Rats ; Seeds ; chemistry ; Strychnos nux-vomica ; chemistry

Polyethylene glycol (PEG) is extensively used to increasing the in vivo and in vitro stability of liposomes. However, PEGylated liposomes also produce some negative effects with further research, such as low cellular uptake, poor "endosomal escape" of pH sensitive liposome (PSL) and accelerated blood clearance (ABC) phenomenon, and this situation is referred as the "PEG dilemma". "PEG dilemma" posed severe challenges for the targeted delivery of PEGylated liposomes-loaded anticancer drugs, effective intracellular release of PEGylated PSL-encapsulated gene and protein drugs, and repeated administration of PEGylated liposomes. Therefore, it is urgent to solve the "PEG dilemma". This review focused on the definition, classification of "PEG dilemma", and discussed several possible approaches to overcome "PEG dilemma".
Antineoplastic Agents ; chemistry ; Drug Carriers ; chemistry ; Liposomes ; chemistry ; Polyethylene Glycols ; chemistry

AIMTo compare sonoporation effect of two phospholipids-based vectors-liposomes and microbubbles on cultured cell membrane.

METHODSA breast cancer cell line SK-BR-3 was exposed to ultrasound alone, 2% or 5% liposome + ultrasound and 2% or 5% microbubble + ultrasound, separately. Immediately after the experiment and 24 h after ultrasound exposure, atomic-force microscopy (AFM) scanning was used to observe the membrane change of SK-BR-3 cells.

RESULTSAfter ultrasound exposure, normal SK-BR-3 cells more or less lost their natural shape, showing elliptic outline with obtuse curved boundary. In groups added with phospholipids-based microbubbles, more obtuse curved boundary of cells was observed. The membrane pores of SK-BR-3 cells had apparent changes after ultrasound exposure. With AFM technique, membrane pores under ultrasound alone or ultrasound with liposomes conditions were enlarged, the diameter of some pores exceeding 1 microm. But all the membrane pores in these conditions returned to normal appearance after 24 hours. In ultrasound with 2% microbubble condition, most membrane pores were about 1 - 3 microm in size and returned to normal appearance after 24 h. In ultrasound with 5% microbubble condition, however, pores of most cell membrane porosity was about 2 - 4 pm and did not totally return to normal appearance after 24 h.

CONCLUSIONAt 2% concentration, phospholipids-based microbubble could enhance ultrasonic sonoporation effect and produce reparable membrane pores on SK-BR-3 cells, which appeared to be a promising vehicle for drug and gene delivery.

Cell Membrane Permeability ; Drug Carriers ; Liposomes ; Microbubbles ; Phospholipids ; chemistry ; Porosity ; Sonication ; instrumentation ; Technology, Pharmaceutical