Research Progress on Application of Borneol As Permeation Enhancer in Functional Cosmetics

Borneol, as a traditional natural permeation enhancer, has been widely used to promote the transdermal absorption of active ingredients. In this review, the mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described. The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced. The application of borneol as a natural ingredient added to functional cosmetics was summarized, and its effects on skin-spot treatment, acne skin care, eczema skin care, skin repair and anti-oxidation were introduced. Finally, the possible problems in the application of borneol in cosmetics were put forward, and the application prospect of borneol in the development of cosmetics was given.

Research Progress on Application of Borneol as Permeation Enhancer in Functional Cosmetics

Borneol,as a traditional natural permeation enhancer,has been widely used to promote the transdermal absorption of active ingredients.The mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described.The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced.The application of borneol as a natural ingredient added to functional cosmetics was summarized,and its effects on skin-spot treatment,acne skin care,eczema skin care,skin repair and anti-oxidation were introduced.Finally,the possible problems in the application of borneol in cosmetics were put forward,and the application prospect of borneol in the development of cosmetics was given。

Novel chemical permeation enhancers for transdermal drug delivery

Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration,with advantages of prolonged therapeutic action,decreased side effect,easy use and better patient compliance.However,development of transdermal products is primarily hindered by the low permeability of the skin.To overcome this barrier effect,numerous new chemicals have been synthesized as potential permeation enhancers for transdermal drug delivery.In this review,we presented an overview of the investigations in this field,and further implications on selection or design of suitable permeation enhancers for transdermal drug delivery were also discussed.

Potential of Essential Oils as Alternative Permeation Enhancers for Transdermal Delivery

Transdermal drug delivery plays a significant part in the drug delivery system when compared to other routes of drug administration.The function of the stratum corneum(SC)is a barrier.Recently,numerous methods have been thrived to improve the perforation of drugs across the skin.The most effective method is to use enhancers since these agents enhance skin permeability.Natural penetration enhancers like essential oils demonstrate higher enhancement activity and are more widely accepted than synthetic penetration enhancers.High potential in the expansion and interaction with the SC intercellular lipids has led to an increasing interest in these oils as penetration enhancers.This article gives an overview of a few essential oils,including their mode of action and important parameters for permeation improvement.The present work can provide essential oils as alternative enhancers,and this could be useful in transdermal administration.

Effect of paracellular permeation enhancers on intestinal permeability of two peptide drugs,enalaprilat and hexarelin, in rats

Transcellular permeation enhancers are known to increase the intestinal permeability of enalaprilat,a 349 Da peptide,but not hexarelin(887 Da).The primary aim of this paper was to investigate if paracellular permeability enhancers affected the intestinal permeation of the two peptides.This was investigated using the rat single-pass intestinal perfusion model with concomitant blood sampling.These luminal compositions included two paracellular permeation enhancers,chitosan(5 mg/mL) and ethylenediaminetetraacetate(EDTA,1 and 5 mg/mL),as well as low luminal tonicity(100 mOsm) with or without lidocaine.Effects were evaluated by the change in lumen-to-blood permeability of hexarelin and enalaprilat,and the blood-to-lumen clearance of ^(51)chromium-labeled EDTA(CL_(Cr-EDTA)),a clinical marker for mucosal barrier integrity.The two paracellular permeation enhancers increased the mucosal permeability of both peptide drugs to a similar extent.The data in this study suggests that the potential for paracellular permeability enhancers to increase intestinal absorption of hydrophilic peptides with low molecular mass is greater than for those with transcellular mechanism-of-action.Further,the mucosal blood-to-lumen flux of ^(51)Cr-EDTA was increased by the two paracellular permeation enhancers and by luminal hypotonicity.In contrast,luminal hypotonicity did not affect the lumen-to-blood transport of enalaprilat and hexarelin.This suggests that hypotonicity affects paracellular solute transport primarily in the mucosal crypt region,as this area is protected from luminal contents by a constant water flow from the crypts.

Rod-like mesoporous silica nanoparticles facilitate oral drug delivery via enhanced permeation and retention effect in mucus

The physiochemical characteristics of nanoparticles affect their in vitro and in vivo performance significantly,such as diameter,surface chemistry,and shape.This paper disclosed the effect of enhanced permeation and retention(EPR)in mucus caused by nanoparticle shape on improving oral absorption.The spherical and rod-like mesoporous silica nanoparticles(MSNs)were used to evaluate shape effect of EPR in mucus.Fenofibrate was loaded in MSNs as model drug.The in vitro release of fenofibrate from MSNs was dependent on nanoparticle shapes,but faster than that of raw drug.The drug release slowed down with the increase of aspect ratio due to longer channels in rod-like MSNs with higher aspect ratio.However,in vivo study showed that the oral bioavailability of fenofibrate was the highest after loading in rod-like MSNs with aspect ratio of 5.The in vitro study of mechanisms revealed that superior mucus diffusion ability of rod-like MSNs with aspect ratio of 5 was conductive to higher bioavailability.Meanwhile,more rod-like MSNs with higher aspect ratio were able to diffuse into mucus and reside there compared to spherical and short counterparts,which demonstrated higher aspect ratio was beneficial to EPR effect of nanoparticles in mucus.This study provides significant implication in rational oral drug carrier design.

Ionic liquids in transdermal drug delivery system: Current applications and future perspectives

The transdermal drug delivery(TDD) shows considerable advantages over other administration pathways.However, conventional enhancing permeation methods face a series of challenges owing to barrier function provided by the skin, of which enhancing abilities either are so strong that it results in toxicity and irritation, or too weak to achieve desirable therapeutical effects. To address these issues, it is an urgent need to develop a novel method to overcome the limitations of current measures. Fortunately, in the preceding decades, ionic liquids(ILs) have been extensively studied and increasingly applied in pharmaceutical drug delivery due to their unique physicochemical and biological properties. What is more, tunability of structure resolves the challenges in processing active pharmaceutical ingredient(API) formulation, such as polymorphism and poor solubility of drugs. Thus, the presence of ILs provides an ample design space for the transdermal drug delivery system(TDDS). This review discusses the shortcomings of conventional enhancing permeation methods and introduces the application of ILs in transdermal delivery from three aspects: i) ILs are applied as enhancers to weaken the barrier function of the stratum corneum(SC). ii) As counterions, ILs are combined with API to modify the physicochemical properties of drugs. iii) ILs assist in the design of transdermal preparation for perfecting formulation. This review comprehensively introduces the major breakthroughs made in the applications of ILs, which can serve as guidance to provide novel ideas for formulation scientists who hit the bottleneck in the development of TDD.

Oral delivery of proteins and peptides:Challenges, status quo and future perspectives

Proteins and peptides(PPs)have gradually become more attractive therapeutic molecules than small molecular drugs due to their high selectivity and efficacy,but fewer side effects.Owing to the poor stability and limited permeability through gastrointestinal(GI)tract and epithelia,the therapeutic PPs are usually administered by parenteral route.Given the big demand for oral administration in clinical use,a variety of researches focused on developing new technologies to overcome GI barriers of PPs,such as enteric coating,enzyme inhibitors,permeation enhancers,nanoparticles,as well as intestinal microdevices.Some new technologies have been developed under clinical trials and even on the market.This review summarizes the history,the physiological barriers and the overcoming approaches,current clinical and preclinical technologies,and future prospects of oral delivery of PPs.

The complexation of insulin with sodium N-[8-(2-hydroxybenzoyl)amino]-caprylate for enhanced oral delivery:Effects of concentration, ratio, and pH

Permeation enhancers(PEs),such as N-[8-(2-hydroxybenzoyl)amino]-caprylate(SNAC),have been reported to improve the oral absorption of various macromolecules.However,the bioavailabilities of these formulations are quite low and variable due to the influences of enzymes,pH and other gastrointestinal barriers.In this study,we revealed that SNAC could interact with insulin to form tight complexes in a specific concentration(insulin≥ 40μg/mL)-,ratio(SNAC/insulin≥ 20:1)-and pH(≥ 6.8)-dependent manner,thus contributing to a significantly high efficacy of oral insulin delivery.Specifically,absorption mechanism studies revealed that the SNAC/insulin complexes were internalized into the cells by passive diffusion and remained intact when transported in the cytosol.Furthermore,the complexes accelerated the exocytosis of insulin to the basolateral side,thereby enhancing its intestinal mucosal permeability.Eudragit;S100-entrapped SNAC/insulin microspheres were then prepared and exhibited an apparent permeability coefficient(P;) that was 6,6-fold higher than that of the insulin solution.In diabetic rats,hypoglycemic activity was sustained for more than 10 h after the microspheres were loaded into entericcoated capsules.Further pharmacokinetic studies revealed an approximately 6.3% oral bioavailability in both the fasted and fed states,indicating a negligible food effect.Collectively,this study provides insight into the interaction between PEs and payloads and presents an SNAC-based oral insulin delivery system that has high oral bioavailability and patient-friendly medication guidance.