Ascorbyl Phosphate Research Articles

Effect of sodium ascorbyl phosphate on promotion of osteoblast differentiation and its application to treatment of periodontal disease

Effect of sodium ascorbyl phosphate on promotion of osteoblast differentiation and its application to treatment of periodontal disease

Fabrication and characterization of hyaluronic acid microneedles to enhance delivery of magnesium ascorbyl phosphate into skin.

This study investigated the in vitro transdermal delivery of magnesium ascorbyl phosphate (MAP) through porcine ear skin treated with hyaluronic acid (HA) microneedles (MNs). In this study, the micro-molding method was used to fabricate HA MNs. HA solution (10% w/v) containing 3% of MAP was placed onto a poly(dimethyl siloxane) mold to fill the microchannels under vacuum followed by drying in a desiccator. Scanning electron microscopy was performed to record the dimensions of the MNs. Skin microporation was demonstrated by dye binding. Histological skin sections revealed the shape of microchannels under hematoxylin-eosin staining. The actual depth of the microchannels and drug distribution pathways were studied by confocal microscopy. In vitro permeation on Franz diffusion cells were performed to determine the rate and extent of drug delivery into and across the skin. SEM captured individual MNs from the array, and the length of each MN was found to be ~400μm. The 10 × 10 MN array prepared, resulted in the formation of 95 to 100 microchannels after 2mins of treatment. In addition, the histological evaluations showed the formation of microchannels in the skin, complementary in shape to the MNs. The depths of the formed microchannels amounted to ~125μm as determined by confocal microscopy. The application of the current MN technology enhanced the delivery of MAP into skin (96.8 ± 3.9μg/cm2) compared to the passive delivery strategy of MAP (44.9 ± 16.3μg/cm2). HA MNs markedly enhanced the in vitro transdermal delivery of MAP into and across skin.

Intramelanocytic Acidification Plays a Role in the Antimelanogenic and Antioxidative Properties of Vitamin C and Its Derivatives.

Although vitamin C (VC, L-ascorbic acid) has been widely used as a skin lightening agent for a long time, the mechanism by which it inhibits melanogenesis remains poorly understood. It is well-documented that the intramelanocytic pH is an important factor in regulating tyrosinase function and melanosome maturation. The activity of tyrosinase, the rate-limiting enzyme required for melanin synthesis, is generally minimal in an acidic environment. Given that VC is an acidic compound, we might speculate that the intracellular acidification of melanocytes induced by VC likely reduces melanin content through the suppression of tyrosinase activity. The results of this study reveal that treatment of melanocytes with VC or its derivatives, magnesium ascorbyl phosphate (MAP) and 3-O-ethyl-L-ascorbic acid (AAE), resulted in significant decreases in the tyrosinase activity and melanin content and in the levels of intracellular reactive oxygen species (ROS), indicating that VC and its derivatives possess antimelanogenic and antioxidative activities. Western blotting analysis indicated that VC, MAP, and AAE exert their antimelanogenic activity by inhibiting the tyrosinase activity rather than by downregulating the expression of melanogenic proteins such as tyrosinase, premelanosome protein 17 (Pmel17) and microphthalmia-associated transcription factor (MITF). Further, we found that the reduced tyrosinase activity of melanocytes treated with VC or its derivatives could be reactivated following intracellular neutralization induced by ammonium chloride (NH4Cl) or concanamycin A (Con A). Finally, we examined the expression of sodium-dependent VC transporter-2 (SVCT-2) using western blotting and qPCR, which revealed that there was a significant increase in the expression of SVCT-2 in melanocytes following treatment with VC. VC-mediated intracellular acidification was neutralized by phloretin (a putative SVCT-2 inhibitor) in a dose-dependent manner. Taken together, these data show that VC and its derivatives suppress tyrosinase activity through cytoplasmic acidification that potentially results from enhanced VC transmembrane transport via the VC transporter SVCT-2.

Co-Spray-Dried Urea Cross-Linked Hyaluronic Acid and Sodium Ascorbyl Phosphate as Novel Inhalable Dry Powder Formulation

The pathogenesis and progression of several lung disorders is propagated by inflammatory and oxidative processes, which can be controlled by adjunctive inhaled therapies. The present study aimed to develop an inhalable dry powder formulation consisting of co-spray-dried urea-crosslinked hyaluronic acid and sodium ascorbyl phosphate (SD HA-CL–SAP), a novel combination which was recently shown to possess anti-inflammatory, antioxidant, and wound healing properties. Native HA and SAP were co-spray dried (SD HA–SAP) and evaluated as control formulation. Yield (Y%) and encapsulation efficiency (EE%) were 67.0 ± 4.8% and 75.5 ± 7.2% for SD HA–SAP, 70.0 ± 1.5% and 66.5 ± 5.7% for SD HA-CL–SAP, respectively. Both formulations were shown to be suitable for lung delivery in terms of morphology, particle size (median volumetric diameter ∼ 3.4 μm), physical and thermal stability, in vitro aerosol performance - respirable fraction: 30.5 ± 0.7% for SD HA–SAP and 35.3 ± 0.3% for SD HA-CL–SAP. SAP release was investigated using Franz cells and air-interface Calu-3 cell model (>90% of SAP transported within 4 h). The innovative SD HA-CL–SAP formulation holds potential as inhalable dry powder for the treatment of inflammatory lung disorders.

Ascorbic acid derivative-loaded modified aspasomes: formulation, in vitro, ex vivo and clinical evaluation for melasma treatment

Vitamin C (L-Ascorbic acid) has many favourable effects on the skin such as antioxidant, anti-aging and whitening effects. Its instability and low permeability limit its pharmaceutical use in cosmetic and dermatological products. Instead, Mg ascorbyl phosphate (MAP), an ascorbic acid derivative, has the same effect with higher stability is being used. In this work, a vesicular system, aspasomes, containing MAP was developed and evaluated. Aspasomes are multilayered vesicles formed by amphiphiles molecules, Ascorbyl palmitate (ASP), in combination with cholesterol and charged lipids for drug encapsulation. Here, we investigated the use of lecithin instead of the charged lipid dicetyl phosphate for aspasomes development. Nine formulations were prepared and evaluated for their entrapment efficiency, particle size, polydispersity index (PDI) and zeta potential. Their entrapment efficiency ranged from 33.00 ± 2.27 to 95.18 ± 1.06, while their particle size was from 373.34 ± 60.85 to 464.37 ± 93.46 nm with acceptable PDI (from 0.212 ± 0.068 to 0.351 ± 0.061) and zeta potential (from −37.52 ± 2.42 to −50.36 ± 1.82). Three formulations were selected and evaluated for their drug release, permeation and retention into skin. One formulation was selected to be formulated as aspasomal topical cream and gel. The aspasomal cream was found to have enhanced drug permeation and skin retention over the aspasomal gel as well as the aspasomes formulation. MAP aspasomal cream was evaluated clinically as an effective treatment for melasma against 15% trichloroacetic acid (TCA) and the results recorded that the aspasomal cream showed the greatest degree of improvement regarding the hemi-MASI scores with 35% of patients rating it as excellent treatment. The study showed that MAP aspasomal cream can be considered a novel treatment of melasma which is free of side effects. Its efficacy as a monotherapy is superior to that of chemical peeling using 15% TCA.

A novel fluorescence immunoassay based on AgNCs and ALP for ultrasensitive detection of sulfamethazine (SMZ) in environmental and biological samples

A novel indirect competitive fluorescence immunoassay based on the quenching of I- to silver clusters (AgNCs) was developed for the highly selective and ultrasensitive detection of sulfamethazine (SMZ). In this system, alkaline phosphatase (ALP) was labeled on the secondary antibody (Ab2). And after a competition step, magnesium ascorbyl phosphate could be catalyzed to produce ascorbic acid under the catalysis of ALP. Subsequently, I2 was introduced and further reduced to I- in the presence of ascorbic acid, triggering the fluorescence quenching of AgNCs dispersed in isopropanol (IPA) buffer. More importantly, trace I- could lead to an obvious reduction in fluorescence signal, indicating the sensitivity of this method would be greatly improved. Under the optimal condition, this improved method for the SMZ detection has a lower detection of limit (LOD, 0.05000 μg/L) with a wider range (0.1400–71.71 μg/L). After an evaluation, the fluorescence ELISA proposed in this work has satisfactory accuracy and reliability (recoveries, 84.18–118.6%; CV, 2.03–7.64%), illustrating good performance and great potential for the detection of trace SMZ in environmental and biological samples.

In vitro characterization of physico-chemical properties, cytotoxicity, bioactivity of urea-crosslinked hyaluronic acid and sodium ascorbyl phosphate nasal powder formulation

An innovative lyophilized dry powder formulation consisting of urea-crosslinked hyaluronic acid (HA-CL) and sodium ascorbyl phosphate (SAP) – LYO HA-CL – SAP- was prepared and characterized in vitro for physico-chemical and biological properties. The aim was to understand if LYO HA-CL – SAP could be used as adjuvant treatment for nasal inflammatory diseases. LYO HA-CL – SAP was suitable for nasal delivery and showed to be not toxic on human nasal septum carcinoma-derived cells (RPMI 2650 cells) at the investigated concentrations. It displayed porous, polygonal particles with unimodal, narrow size distribution, mean geometric diameter of 328.3 ± 27.5 µm, that is appropriate for nasal deposition with no respirable fraction and 88.7% of particles with aerodynamic diameter >14.1 µm. Additionally, the formulation showed wound healing ability on RPMI 2650 cells, and reduced interleukin-8 (IL-8) level in primary nasal epithelial cells pre-induced with lipopolysaccharide (LPS). Transport study across RPMI 2650 cells showed that HA-CL could act not only as carrier for SAP and active ingredient itself, but potentially also as mucoadhesive agent. In conclusion, these results suggest that HA-CL and SAP had anti-inflammatory activity and acted in combination to accelerate wound healing. Therefore, LYO HA-CL – SAP could be a potential adjuvant in nasal anti-inflammatory formulations.

Influence of Emollient on the Preparation and stability of Sodiun Ascorbyl Phospate Cream

As a type of cosmetic preparation products, cream dosage form is widely used with the addition of active substances having antioxidant activities, such as vitamin C and its derivatives. Sodium ascorbyl phosphate (SAP) can be used in topical formulation due to its more stable properties than ascorbic acid. However, it is difficult to deliver SAP into the dermis in a suficient dose. To overcome the problem, occasionally we can add a penetration enhancer. In some literature, emollients that often added in cosmetic preparations also have another effect as a penetration enhancer. The purpose of this research was to observe wether emollient addition could influence the penetration of SAP in the cream formulation or not. SAP was formulated into four formulations with three different emollients: dimethicone (F1), capric triglyceride (F2), and isopropyl myristate (F3) and a formulation without the addition of emollients (F4). The diffusion test was performed by Franz's diffusion cell method using male wistar rat’s abdominal membrane as a standard model of the skin barrier. The result of stability test showed that SAP cream was stable at room temperature but unstable on freeze thaw condition described by significant different values for all formulas. Nonetheless, the diffusion test showed that F2 with the capric triglyceride as emollient had the highest ability to pass SAP through the membrane, followed by isopropyl miristate. We concluded that emollient addition could influence the penetration of the cream of SAP.Keywords: vitamin c, ascorbic acid, sodium ascorbyl phospate, emollient, penetration enhancer

Новая композиция твердофазных модификаций гиалуроновой кислоты протеиногенными аминокислотами HR-2 увеличивает метаболическую активность фибробластов без выраженных пролиферативных эффектов

Гетерополисахарид гиалуронан, являясь ключевым компонентом внеклеточного матрикса, играет важную роль в поддержании определенных физико-химических условий в тканях. Кроме того, гиалуронан может модулировать состояние клеток через взаимодействие с рецепторами и эндоцитоз, однако, эти эффекты недостаточно изучены. Благодаря своим уникальным свойствам, гиалуронан нашел широкое применение в разных областях биомедицины, в частности, активно используется в качестве микроимплантатов в дерму для коррекции возрастных изменений кожи. Вместе с тем, нативный гиалуронан нестабилен при инъекции и подвергается быстрой деградации в ткани, что существенно ограничивает продолжительность вызываемых им эффектов. В данной работе исследуется новая композиция на основе гиалуронана - HR-2, которую отличают ковалентные сшивки между цепями, введенные путем разработанной авторами одностадийной технологии твердофазной модификации полисахаридов. Сшивки препятствуют быстрой деградации гиалуронана. Авторами предложена концепция функционирования гиалуронана в ткани в качестве депо протеиногенных аминокислот и витаминов в целях поддержания биосинтетической активности клеток. Ранее было показано, что сшитый по данной технологии гиалуронан более стабилен в дерме, в связи с чем его действие в качестве депо может быть пролонгировано. В данной работе исследуется влияние на эндотелиоцитоподобные клетки и фибробласты препарата HR-2, представляющего собой новую композицию гиалуроната натрия и сополимера гиалуроновой кислоты с аскорбилфосфатом магния с добавлением глицина, пролина, лизина. В работе проводится сравнение с немодифицированным гиалуронатом натрия. Установлено, что композиция HR-2 в сравнительно высоких концентрациях дозозависимо увеличивает активность дегидрогеназ в фибробластах, что может свидетельствовать о метаболическом их стимулировании. Это отличает препарат HR-2 от нативной гиалуроновой кислоты, ингибирующей в этих же концентрациях метаболическую активность фибробластов. Оба препарата - и HR-2, и нативная гиалуроновая кислота - в малых концентрациях вызывают гормезис-подобный, стимулирующий метаболизм эндотелиоцитов эффект. Цитотоксичность композиции HR-2 ниже нативной гиалуроновой кислоты на обоих клеточных типах. Следует также отметить, что не выявлено достоверного пролиферативного действия обоих препаратов. Полученные в работе новые сведения могут быть использованы для оптимизации режимов применения препаратов гиалуроновой кислоты в биомедицине, с целью достижения максимального терапевтического эффекта и снижения нежелательных последствий его применения. Hyaluronan (HA) is a linear heteropolysaccharide, a key component of the extracellular matrix. It plays an important role in maintaining certain physicochemical conditions in tissues. In addition, hyaluronan can modulate the state of cells through interaction with receptors and endocytosis; however, these effects are not well understood. Due to its unique properties, hyaluronan is widely used in various fields of biomedicine, in particular, as microimplant for correction of age-related skin changes. However, native hyaluronan is unstable when injected and undergoes rapid degradation in the tissue, which significantly limits duration of its effects. In this study, we evaluated a new hyaluronan-based composition, HR-2, which is distinguished by covalent cross-links between the chains. Those cross-links were incorporated using a one-stage technology of solid-phase modification of polysaccharides developed by the authors. The cross-links prevent the rapid degradation of hyaluronan. The authors proposed a concept of injecting hyaluronan into tissue as a depot of proteinogenic amino acids and vitamins in order to maintain the biosynthetic activity of cells. Previously it was shown that hyaluronan produced with this technology was more stable in the dermis, and, therefore, its performance as a depot can be prolonged. In this work, we studied the effect on endotheliocyte-like cells and fibroblasts of HR-2, which is a new composition of sodium hyaluronate and a copolymer of hyaluronic acid with magnesium ascorbyl phosphate supplemented with glycine, proline, and lysine. The study compared HR-2 with unmodified sodium hyaluronate. We found that the composition of HR-2 in relatively high concentrations dose-dependently increased dehydrogenase activities in fibroblasts, that might indicate their metabolic stimulation. This differs HR-2 from native hyaluronic acid, which inhibits the metabolic activity of fibroblasts when added in similar concentrations. Low concentrations of both drugs, HR-2 and native hyaluronic acid, exerted a hormesis-like effect on endotheliocyte metabolism. Cytotoxicity of the HR-2 formulation was lower than of native hyaluronic acid in both cell types. It should also be noted that no reliable proliferative effects of both drugs have been identified. The new information obtained in this study can help optimizing the use of hyaluronic acid drugs in biomedicine to achieve the best therapeutic effect and reduce undesirable consequences of its use.

Formulation and Characterization of Native and Crosslinked Hyaluronic Acid Microspheres for Dermal Delivery of Sodium Ascorbyl Phosphate: A Comparative Study.

The present work evaluates for the first time the use of urea-crosslinked hyaluronic acid (HA-CL), a novel derivative of native hyaluronic acid (HA), to produce microspheres (MS) by emulsification-solvent evaporation, for dermal delivery of sodium ascorbyl phosphate (SAP). As the term of comparison, HA MS were prepared. A pre-formulation study—investigation of the effects of polymers solutions properties (pH, viscosity) and working conditions—led to the production of optimized HA-CL MS and HA-CL—SAP MS with: almost unimodal size distributions; mean diameter of 13.0 ± 0.7 and 9.9 ± 0.8 µm, respectively; spherical shape and rough surface; high yield, similar to HA MS and HA–SAP MS (≈ 85%). SAP was more efficiently encapsulated into HA-CL MS (78.8 ± 2.6%) compared to HA MS (69.7 ± 4.6%). Physical state, thermal properties, relative moisture stability of HA-CL MS and HA-CL–SAP MS were comparable to those of HA MS and HA–SAP MS. However, HA-CL–SAP MS exhibited an extended drug release compared to HA–SAP MS, despite the same kinetic mechanism—contemporaneous drug diffusion and polymer swelling/dissolution. Therefore, HA-CL formulation showed a greater potential as microcarrier (for encapsulation efficiency and release kinetic), that could be improved, in future, using suitable excipients.

Combination of urea-crosslinked hyaluronic acid and sodium ascorbyl phosphate for the treatment of inflammatory lung diseases: An in vitro study

This in vitro study evaluated, for the first time, the safety and the biological activity of a novel urea-crosslinked hyaluronic acid component and sodium ascorbyl phosphate (HA-CL – SAP), singularly and/or in combination, intended for the treatment of inflammatory lung diseases. The aim was to understand if the combination HA-CL – SAP had an enhanced activity with respect to the combination native hyaluronic acid (HA) – SAP and the single SAP, HA and HA-CL components. Sample solutions displayed pH, osmolality and viscosity values suitable for lung delivery and showed to be not toxic on epithelial Calu-3 cells at the concentrations used in this study. The HA-CL – SAP displayed the most significant reduction in interleukin-6 (IL-6) and reactive oxygen species (ROS) levels, due to the combined action of HA-CL and SAP. Moreover, this combination showed improved cellular healing (wound closure) with respect to HA – SAP, SAP and HA, although at a lower rate than HA-CL alone. These preliminary results showed that the combination HA-CL - SAP could be suitable to reduce inflammation and oxidative stress in lung disorders like acute respiratory distress syndrome, asthma, emphysema and chronic obstructive pulmonary disease, where inflammation is prominent.

EFFECTIVNESS OF GLUTATHIONE (GSH) 2%, TOCOPHERYL ACETATE 1%, AND MAGNESIUM ASCORBYL PHOSPHATE 3% COMBINATION CREAM COMPARED WITH HYDROQUINONE 4% CREAM AS A SKIN LIGHTENING AGENT: A RANDOMISED STUDY

Black spots and brown spots interfere with aesthetic appearance. For this reason, there are various skin lightening products on the market, such as glutathione, vitamin C, and E. The combination of glutathione, vitamin C, and E, which is a natural antioxidant, is expected to have an equivalent effect with hydroquinone (standard therapy), but with minimal side effects. The aim of this study was to determine the score of skin brightness using Chroma Meter on the subjects before the topical glutathione (GSH) 2%, 1% tocopheryl acetate 1%, and 3% magnesium ascorbyl phosphate 3% combination therapy compared with hydroquinone 4% cream after 6 weeks of administration. A double-blind, pre- and post-treatment randomized controlled clinical trial was conducted on 34 patients at the Dermatology and Venereology clinic of Hasanuddin University Hospital in Makassar, by applying combination cream and hydroquinone on the patient's right arm twice daily. Measurement of skin brightness and erythema using Chroma Meter performed weekly. The results of the study using Wilcoxon Signed Rank and Mann-Whitney test found that the L* (brightness) score in combination cream group was significantly higher than in the hydroquinone cream group (p

A novel magnesium ascorbyl phosphate graphene-based monolith and its superior adsorption capability for bisphenol A

In this study, a non-shell graphene-based monolith (GBM) with huge surface area was synthesized by chemical reduction of Graphene oxide (GO) using magnesium ascorbyl phosphate (MAP), and tested as an adsorbent for trace Bisphenol A (BPA) removal. The properties of MAP-GBM was characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller N2 specific surface area (BET), X-ray powder diffraction, Fourier transform-infrared (FTIR), Raman, and X-ray photoelectron spectroscopies. BPA adsorption was investigated in batch and column adsorption experiments. The data showed that MAP-GBM was a three-dimensional (3D) graphene material with macrostructure and most CC double bonds were recovered. Adsorption isotherms and kinetics of BPA on MAP-GBM followed the Langmuir model and fitted well with a pseudo-second-order kinetic model, respectively, and the adsorption process was endothermic. The saturated adsorption capacity of MAP-GBM was 324 mg/g for BPA, which was 2.43 times of that of ascorbic acid-GBM. A MAP-GBM adsorption column completely removed BPA from solution at low concentration (50 μg/L) for ∼450 mL.This efficiency is much higher than traditional adsorbents such as activated carbon, which could be ascribed to the unique 3D porous structure, hydrogen bonding, and π-π interaction characteristics of this MAP-GBM. The material can be easily regenerated by simply immersing in methanol for 24 h, and the adsorption efficiency remain as high as 88% after five regenerations. These findings demonstrated that MAP-GBM is a promising adsorbent for the effective and cost-efficient removal of low concentration endocrine-disrupting chemicals.

Anti- and pro-oxidative activity measured directly as the extent of 8-oxoguanine production

An electrochemical method was developed for the evaluation of antioxidant activity based on the ability to inhibit 8‐oxoguanine production. It consists of a sequence of successive potential hold and scan steps, in which superoxide anion radical is generated by the reduction of dioxygen in a potential hold step in a buffer solution containing guanine and antioxidant, immediately followed by a potential scan step, in which 8-oxoguanine is detected and its amount determined. The effect of 11 antioxidants, among them simple alcohols for comparison, was investigated in pH 7 and pH 9 phosphate buffers saturated with guanine. The plots of 8-oxoguanine peak height, expressed as percent of the peak current in the absence of antioxidants, versus antioxidant concentration showed an exponential decay character. The decay parameter may be used as a measure of antioxidant activity. It is directly related to the IC50 coefficient used in other methods Only simple alcohols displayed single decay character. Other studied substances showed multi-exponential decay at pH 7, most investigated antioxidants were unable to entirely inhibit the generation of 8-oxoguanine, but led to a steady state of 8-oxoguanine level. At pH 9, many antioxidants, particularly polyphenolics and ascorbyl phosphate, showed pure pro-oxidant activity.

A novel thermo-mechanical system enhanced transdermal delivery of hydrophilic active agents by fractional ablation

The Tixel is a novel device based on a thermo-mechanical ablation technology that combines a sophisticated motion and a temperature control. The fractional technology is used to transfer a very precise thermal energy to the skin thereby creating an array of microchannels, accompanying by no signs of pain or inconvenience. This study aimed to evaluate the effect of the Tixel on the skin permeability of three hydrophilic molecular models: verapamil hydrochloride, diclofenac sodium, and magnesium ascorbyl phosphate. Tixel’s gold-platted stainless steel tip heated to a temperature of 400°C was applied on skin for 8ms or 9ms at a protrusion of 400μm (the distance in which the tip protrudes beyond the distance gauge). The experiments were carried out partly in vivo in humans using a fluorescent dye and a confocal microscopy and partly in vitro using porcine skin and a Franz diffusion cell system. The results obtained in this study have shown that (a) no significant collateral damage to the skin tissue and no necrosis or dermal coagulation have been noted, (b) the microchannels remained open and endured for at least 6h, and (c) the skin permeability of hydrophilic molecules, which poorly penetrate the lipophilic stratum corneum barrier, was significantly enhanced by using Tixel’s pretreatment.

Efficacy of Trichloro-Acetic Acid Peel Alone Versus Combined Topical Magnesium Ascorbyl Phosphate for Epidermal Melasma.

To compare the efficacy in terms of reduction in melasma area and severity index (MASI) score by more than 10 of a combination of 20% trichloro-acetic acid peel plus 5% topical magnesium ascorbyl phosphate versus 20% trichloroacetic acid peel alone in the treatment of epidermal melasma. Randomized controlled trial. Department of Dermatology, Lady Reading Hospital (LRH), Peshawar, from May 2012 to May 2013. Patients aged 18 - 65 years, with Fitzpatrick skin type III-V were divided into two equal groups having 74 patients each. Detailed history was taken and Wood's lamp examination done to rule out mixed and dermal melasma. Melasma area and severity index (MASI) score was calculated for every patient. Priming was done for all patients with tretinoin cream applied once daily at night for 2 weeks, and to use a broad spectrum sun block cream before sun exposure. Patients in group Awere subjected to combined treatment, i.e. trichloro-acetic acid peel 20% (weekly) plus magnesium ascorbyl phosphate cream (applied once daily), while patients in group B were subjected to trichloro-acetic acid peel 20% (weekly) alone. Treatment was continued for 6 weeks. After completion of treatment, MASI score was recalculated. Proportion of patients with significant MASI score reduction was compared using chi-square test with significance at p < 0.05. Male and female patients were 11 (14.9%) and 63 (85.1%), respectively in group A, whereas 13 (17.6%) and 61 (82.4%) in group B. The mean age in group Awas 30.28 ±8.08 years, and 29.36 ±6.84 years in group B. Significant MASI score reduction in group Awas seen in 60 (81.1%) patients and in group B 49 (66.2%, p= 0.040). Combination of trichloro-acetic acid peel and topical magnesium ascorbyl phosphate cream was significantly more effective than trichloro-acetic acid peel alone in treatment of melasma.

A fluorescence turn on assay for alkaline phosphatase based on the Cu2+ catalyzed Fenton-like reaction

A fluorescence turn-on assay was established for ALP (alkaline phosphatase) based on Cu2+ catalyzed Fenton-like reaction and Graphene Oxide (GO). GO was utilized to quench the fluorescence of fluorescein (FAM) labeled single strand DNA (F-DNA). ALP can remove the phosphate group in sodium ascorbyl phosphate (SAP), and convert it into reducing ascorbate. Highly reactive hydroxyl radicals (·OH) were generated in the presence of ascorbate and Cu2+ through the Fenton-like reaction. The reactive radicals generated in situ caused the cleavage of F-DNA into small fragments. When GO was added, the fluorescence emission of the sample without ALP was quenched and fluorescence emission recovered in the presence of ALP. The intensity of the recovered fluorescence was directly related to the concentration of ALP in the assay solution, and a sensitive and selective facile ALP assay is therefore established.

Effects of Magnesium Ascorbyl Phosphate on the Expression of Inflammatory Biomarkers after Treatment of Cultured Sebocytes with Propionibacterium acnes or Ultraviolet B Radiation.

Vol. 28, No. 1, 2016 129 Received February 5, 2015, Revised March 21, 2015, Accepted for publication March 30, 2015 Corresponding author: Weon Ju Lee, Department of Dermatology, Kyungpook National University School of Medicine, 130 Dongdeok-ro, Jung-gu, Daegu 41944, Korea. Tel: 82-53-420-5838, Fax: 82-53-426-0770, E-mail: weonju@knu.ac.kr This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 2. Hachem JP, Crumrine D, Fluhr J, Brown BE, Feingold KR, Elias PM. pH directly regulates epidermal permeability barrier homeostasis, and stratum corneum integrity/cohesion. J Invest Dermatol 2003;121:345-353. 3. Devillers AC, de Waard-van der Spek FB, Mulder PG, Oranje AP. Treatment of refractory atopic dermatitis using 'wet-wrap' dressings and diluted corticosteroids: results of standardized treatment in both children and adults. Dermatology 2002;204:50-55. 4. Fluhr JW, Elias PM. Stratum corneum pH: formation and function of the acid mantle. Exog Dermatol 2002;1:163175. 5. Hachem JP, Roelandt T, Schurer N, Pu X, Fluhr J, Giddelo C, et al. Acute acidification of stratum corneum membrane domains using polyhydroxyl acids improves lipid processing and inhibits degradation of corneodesmosomes. J Invest Dermatol 2010;130:500-510. 6. Holleran WM, Takagi Y, Uchida Y. Epidermal sphingolipids: metabolism, function, and roles in skin disorders. FEBS Lett 2006;580:5456-5466. 7. Akiyama H, Yamasaki O, Tada J, Kubota K, Arata J. Antimicrobial effects of acidic hot-spring water on Staphylococcus aureus strains isolated from atopic dermatitis patients. J Dermatol Sci 2000;24:112-118. 8. Devillers AC, Oranje AP. Efficacy and safety of 'wet-wrap' dressings as an intervention treatment in children with severe and/or refractory atopic dermatitis: a critical review of the literature. Br J Dermatol 2006;154:579-585. 9. Hatano Y, Man MQ, Uchida Y, Crumrine D, Scharschmidt TC, Kim EG, et al. Maintenance of an acidic stratum corneum prevents emergence of murine atopic dermatitis. J Invest Dermatol 2009;129:1824-1835. 10. Lee HJ, Yoon NY, Lee NR, Jung M, Kim DH, Choi EH. Topical acidic cream prevents the development of atopic dermatitisand asthma-like lesions in murine model. Exp Dermatol 2014;23:736-741.

Efficacy of transdermal magnesium ascorbyl phosphate delivery after ultrasound treatment with microbubbles in gel-type surrounding medium in mice

Liquid microemulsions appropriate for topical application were obtained by increasing their viscosity through the addition of thickening agents. The present study first assessed the usefulness of ultrasound (US) plus US contrast agent, microbubbles (MBs), in agarose gel for enhancing transdermal drug delivery. The effect of US plus MBs in agarose gel on the penetration of the skin by magnesium ascorbyl phosphate (MAP) was explored both in vitro and in vivo. In the in vitro experiments, the stability of MBs was investigated by examining the penetration of MAP by the model drug, Evans blue, in two media: an agarose phantom and pig skin. The penetration depth in the agarose phantom and pig skin increased by 40% and 195%, respectively, when treated with US plus MBs in 0.1% agarose solution combined with MAP (UMB1), and by 48% and 206%, respectively, when treated with US plus MBs in 0.15% agarose solution and MAP (UMB2). The skin-whitening effects in C57BL/6J mice in the UMB1 and UMB2 groups over a 4-week experimental period were significantly increased by 63% and 70%, respectively, in the fourth week. The findings of this study suggest that the survival of MBs with US is affected by the viscosity of the surrounding medium, and that in mice, treatment with US plus MBs in a suitable agarose gel can increase skin permeability and enhance transdermal MAP delivery.

Determination of Whiteners in Cosmetics by Microdialysis and High-Performance Liquid Chromatography

A simple method was developed for the determination of hydrophilic whitening agents (ascorbyl glucoside, magnesium ascorbyl phosphate, arbutin, hydroquinone, and kojic acid) in bleaching cosmetics by high performance liquid chromatography with electrochemical detection. The samples were prepared using microdialysis and were separated within ten minutes using isocratic elution. Linear calibration was achieved for concentrations between 0.10 and 10.00 micromolar. The limits of detection were from 0.6 to 2.0 nanomolar; the recoveries were between 91.43 and 108.04 percent, and the relative standard deviation was less than 6.88 percent. This method was used to determine whitening compounds in several cosmetics with on-line microdialysis and the zero net flux method. The procedure was fast, simple, selective, and suitable for routine analysis.