Dorsal preservation rhinoplasty versus dorsal hump reduction: a randomized prospective study, functional and aesthetic outcomes.

PURPOSE: To compare the functional and esthetic outcomes of dorsal preservation rhinoplasty (DPR) and conventional dorsal hump reduction (DHR) in primary rhinoplasty using patient-reported outcome measures (PROMs) and cone beam computed tomography (CBCT). METHODS: In our randomized prospective double-blinded clinical trial, 50 patients had dorsal nasal hump surgery between October 2021 and November 2022 in our tertiary referral center. All surgeries were done by the same surgeon. Patients were randomly assigned to two groups: Group (A): 25 patients had DPR, and group (B): 25 patients underwent DHR. Pre-operative and post-operative evaluations were conducted using standardized cosmesis and health nasal outcomes survey (SCHNOS), surgeons' rhinoplasty evaluation questionnaire (SREQ), and the CBCT. RESULTS: Following an average of 7.22 ± 2.07 months, patients in both groups reported significantly higher levels of satisfaction, as measured by the SCHNOS score (p < 0.001) and the average of three SREQ scores (p < 0.001). These results align with the radiological analysis, which denoted an overall improvement in the average of both sides' internal nasal valve angle and cross-sectional area after surgery with (p = 0.001) and (p = 0.085), respectively, for the DPR group and with (p = 0.281) and (p = 0.014), respectively, for the DHR group. There was no statistically significant difference in outcomes between both groups (p > 0.05). CONCLUSION: Dorsal preservation is a viable alternative to conventional dorsal hump reduction in primary rhinoplasty. There was no difference in the functional and esthetic outcomes between both techniques, which were verified by radiological investigation.

Tissue engineered periosteum: Fabrication of a gelatin basedtrilayer composite scaffold with biomimetic properties for enhanced bone healing.

The periosteum, a vascularized tissue membrane, is essential in bone regeneration following fractures and bone loss due to some other reasons, yet there exist several research gaps concerning its regeneration. These gaps encompass reduced cellular proliferation and bioactivity, potential toxicity, heightened stiffness of scaffold materials, unfavorable porosity, expensive materials and procedures, and suboptimal survivability or inappropriate degradation rates of the implanted materials. This research used an interdisciplinary approach by forming a new material fabricated through electrospinning for the proposed application as a layer-by-layer tissue-engineered periosteum (TEP). TEP comprises poly(ε-caprolactone) (PCL), PCL/gelatin/magnesium-doped zinc oxide (vascular layer), and gelatin/bioactive glass/COD liver oil (osteoconductive layer). These materials were selected for their diverse properties, when integrated into the scaffold formation, successfully mimic the characteristics of native periosteum. Scanning electron microscopy (SEM) was employed to confirm the trilayer structure of the scaffold and determine the average fiber diameter. In-vitro degradation and swelling studies demonstrated a uniform degradation rate that matches the typical recovery time of periosteum. The scaffold exhibited excellent mechanical properties comparable to natural periosteum. Furthermore, the sustained release kinetics of COD liver oil were observed in the trilayer scaffold. Cell culture results indicated that the three-dimensional topography of the scaffold promoted cell growth, proliferation, and attachment, confirming its non-toxicity, biocompatibility, and bioactivity. This study suggests that the fabricated scaffold holds promise as a potential artificial periosteum for treating periostitis and bone fractures.

Fabrication of green composite hand knitted silk mesh reinforced with silk hydrogel.

Soft tissue defects like hernia and post-surgical fistula formation can be resolved with modern biomaterials in the form of meshes without post-operative complications. In the present study hand knitted silk meshes were surface coated with regenerated silk fibroin hydrogel and pure natural extracts. Two phytochemicals (Licorice extract (LE) and Bearberry extract (BE)) and the two honeybee products (royal jelly (RJ) and honey (HE)) were incorporated separately to induce antibacterial, anti-inflammatory, and wound healing ability to the silk hydrogel coated knitted silk meshes. Meshes were dip coated with a blend of 4 % silk hydrogel (w/v) and 5 % extracts. Dried modified meshes were characterized using SEM, DMA, GC-MS and FTIR. Antimicrobial testing, in-vitro cytotoxicity, in-vitro wound healing and Q-RT-PCR were also performed. SEM analysis concluded that presence of coating reduced the pore size up to 47.7 % whereas, fiber diameter was increased up to 17.9 % as compared to the control. The presence of coating on the mesh improved the mechanical strength/Young's modulus by 1602.8 %, UTS by 451.7 % and reduced the % strain by 51.12 %. Sustained release of extracts from MHRJ (62.9 % up to 72 h) confirmed that it can induce antibacterial activity against surgical infections. Cytocompatibility testing and gene expression results suggest that out of four variables MHRJ presented best cell viability, % wound closure and expression of wound healing marker genes. In-vivo analyses in rat hernia model were carried out using only MHRJ variant, which also confirmed the non- toxic nature and wound healing characteristics of the modified mesh. The improved cell proliferation and activated wound healing in vitro and in vivo suggested that MHRJ could be a valuable candidate to promote cell infiltration and activate soft tissue and hernia repair as a biomedical implant.

Silk Meshes Coated with Chitosan-Bioactive Phytochemicals Activate Wound Healing Genes In Vitro.

Meshes from natural silk are hand knitted and surface functionalized to facilitate hernia repair and other load bearing, tissue applications. Purified organic silk is - hand knitted and then coated with chitosan (CH)/bacterial cellulose (BC) blend polymer using four phytochemicals such as pomegranate (PG) peel, Nigella sativa (NS) seed, Licorice root (LE), and Bearberry leaf extracts (BE) separately. Characterizations using GCMS analysis shows the presence of bioactive chemicals in the extracts. Scanning electron microcopy (SEM) shows that the surface is coated with the composite polymer t. Fourier transform infrared spectroscopy (FTIR) shows significant elements found in CH, BC, and phytochemicals in plant extracts with no chemical changes. Tensile strength of the coated meshes is higher to support tissue as implants. The release kinetics suggest sustained release of phytochemical extracts. In vitro studies confirmed the noncytotoxic, biocompatible, wound healing potential of the meshes. Furthermore, gene expression analysis of 3-wound healing genes shows marked increase in the in vitro cell cultures due to the presence of extracts. These results suggest that the composite meshes can efficiently support hernia closure while facilitating wound/tissue healing and combating bacterial infections. Therefore, these meshes can be good candidates for fistula and cleft palate repair.

Graphene oxide reinforced silk fibroin nanocomposite as an electroactive interface for the estimation of dopamine.

The fabrication of 2D materials and polymer-based nanocomposites deposited on flexible conductive interfaces has unblocked new horizons to expedite reaction kinetics for developing highly selective and sensitive electrochemical biosensors. Herein, we developed a novel biosensing platform, comprising graphene oxide and a silk fibroin-based nanocomposite, drop-cast on a carbon cloth electrode. The fabricated interface was expected to be a robust and miniaturized sensing platform for precise detection of dopamine (DA). Characterization was performed by SEM, EDX, FTIR, XRD, UV-visible spectroscopy, contact angle measurement, fluorescence spectroscopy, particle size, and zeta potential analysis. CV, EIS, DPV, and chronoamperometry demonstrated the superior electrochemical properties of the working interface and revealed its enhanced active surface area, increased conductivity, and accelerated electron transfer rate. The designed interface exhibited low LoD (0.41 µM), admirable stability, good sensitivity (2.46 µA µM-1 cm-2), wide linearity ranging from 100-900 µM, excellent reproducibility, and superb selectivity against dopamine even in the presence of possible interfering analytes. These findings endorse the feasibility of the practical execution of such an integrated system in real sample analysis.

Coblation tonsillectomy versus laser tonsillectomy: a systematic review and meta-analysis of randomized controlled trials.

AIM: This systematic review and meta-analysis of randomized controlled trials (RCTs) evaluated coblation versus laser (carbon dioxide and diode) tonsillectomy, with regard to various surgical and clinical outcomes. METHODS: We searched PubMed, CENTRAL, Scopus, and Web of Science for relevant from inception until March 2021. We evaluated risk of bias using the Cochrane Collaboration Tool. We summarized the outcomes as risk ratio (RR) or mean difference/standardized mean difference (MD/SMD) with 95% confidence interval (CI). We conducted subgroup analysis based on the day of postoperative pain (day 1, day 7, and day 14) and type of postoperative hemorrhage (reactionary and secondary). In addition, we conducted subgroup analysis according to the type of laser. RESULTS: Five RCTs were analyzed. Three and two RCTs were evaluated as having "some concerns" and "low risk of bias", respectively. Coblation tonsillectomy correlated with lower intraoperative blood loss (MD = -5.08 ml, 95% CI [- 7.33 to - 2.84], P < 0.0001) and lower operative time (MD = - 4.50 min, 95% CI [- 6.10 to - 2.90], P < 0.0001) compared with the laser tonsillectomy. However, there was no significant difference between both groups regarding the postoperative pain score (SMD = - 0.27, 95% CI [- 0.72 to 0.17], P = 0.27) and rate of postoperative hemorrhage (RR = 0.95, 95% CI [0.27-3.40], P = 0.23). Subgroup analysis reported similar insignificant difference between both groups according to the day of postoperative pain and type of postoperative hemorrhage. CONCLUSIONS: Coblation tonsillectomy correlated with a significant reduction in intraoperative blood loss and operative time compared with the laser technique. Nevertheless, these effects do not seem clinically meaningful in surgical practice.

Development of Iron Sequester Antioxidant Quercetin@ZnO Nanoparticles with Photoprotective Effects on UVA-Irradiated HaCaT Cells.

BACKGROUND: Solar ultraviolet radiation A (UVA, 320-400 nm) is a significant risk factor leading to various human skin conditions such as premature aging or photoaging. This condition is enhanced by UVA-mediated iron release from cellular iron proteins affecting huge populations across the globe. PURPOSE: Quercetin-loaded zinc oxide nanoparticles (quercetin@ZnO NPs) were prepared to examine its cellular iron sequestration ability to prevent the production of reactive oxygen species (ROS) and inflammatory responses in HaCaT cells. METHODS: Quercetin@ZnO NPs were synthesized through a homogenous precipitation method, and the functional groups were characterized by Fourier transform infrared (FTIR) spectroscopy, whereas scanning electron microscopy (SEM) described the morphologies of NPs. MTT and qRT-PCR assays were used to examine cell viability and the expression levels of various inflammatory cytokines. The cyclic voltammetry (CV) was employed to evaluate the redox potential of quercetin-Fe3+/quercetin-Fe2+ complexes. RESULTS: The material characterization results supported the loading of quercetin molecules on ZnO NPs. The CV and redox potential assays gave Fe-binding capability of quercetin at 0.15 mM and 0.3 mM of Fe(NO3)3. Cytotoxicity assays using quercetin@ZnO NPs with human HaCaT cells showed no cytotoxic effects and help regain cell viability loss following UVA (150 kJ/m2). CONCLUSION: Quercetin@ZnO NPs showed that efficient quercetin release action is UV-controlled, and the released quercetin molecules have excellent antioxidant, anti-inflammatory, and iron sequestration potential. Quercetin@ZnO NPs have superior biocompatibility to provide UVA protection and medication at once for antiphotoaging therapeutics.

Bi-layered α-tocopherol acetate loaded membranes for potential wound healing and skin regeneration.

With an increase in the demand for skin regeneration products, there is a noticeable increase in developing materials that encourage, wound healing and skin regeneration. It has been reported that antioxidants play an important role in anti-inflammatory reactions, cellular proliferation and remodeling phase of wound healing. While consideration all these factors, a novel α-tocopherol acetate (vitamin E) (VE) loaded bi-layered electrospun membrane, based on lower polycaprolactone (PCL) layer and upper polylactic acid (PLA) layer, was fabricated through electrospinning. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), in-vitro degradation studies, swelling studies and VE release studies were performed to evaluate structural, physical and in-vitro behavior of membranes. Biological properties of membranes were evaluated through cell proliferation assay, cell adhesion studies, live/dead cell assay and CAM assay. SEM images showed that the average diameter of nanofibers ranged from 1 to 6 µm, while addition of VE changed the diameter and morphology of fibers. Bi-layered membranes showed significant swelling behavior through water uptake, membranes loaded with 30% VE showed 8.7% and 6.8% degradation in lysozyme and H2O2 respectively. 20% and 30% VE loaded membranes followed Korsmeyer-Peppas and first order drug release kinetics followed by non-fickian drug release kinetics. Membranes showed non-toxic behavior and supported cell proliferation via alamar blue assay, cell adhesion via SEM, cell viability via live/dead assay and wound healing by scratch assay. CAM assay showed that membranes having VE supported angiogenesis and showed significant formation of blood vessels making it suitable for skin regeneration and wound healing. Results showed that large surface area of nanofibers, porous structure and biocompatible nature are suitable for targeted clinical applications.

Fabrication and performance evaluation of blood compatible hemodialysis membrane using carboxylic multiwall carbon nanotubes and low molecular weight polyvinylpyrrolidone based nanocomposites.

This study focused to optimize the performance of polyethersulfone (PES) hemodialysis (HD) membrane using carboxylic functionalized multiwall carbon nanotubes (c-MWCNT) and lower molecular weight grade of polyvinylpyrrolidone (PVP-k30). Initially, MWCNT were chemically functionalized by acid treatment and nanocomposites (NCs) of PVP-k30 and c-MWCNT were formed and subsequently blended with PES polymer. The spectra of FTIR of the HD membranes revealed that NCs has strong hydrogen bonding and their addition to PES polymer improved the capillary system of membranes as confirmed by Field Emission Scanning Electron Microscope (FESEM) and leaching of the additive decreased to 2% and hydrophilicity improved to 22%. The pore size and porosity of NCs were also enhanced and rejection rate was achieved in the establish dialysis range (<60 kDa). The antifouling studies had shown that NCs membrane exhibited 30% less adhesion of protein with 80% flux recovery ratio. The blood compatibility assessment disclosed that NCs based membranes showed prolonged thrombin and prothrombin clotting times, lessened production of fibrinogen cluster, and greatly suppressed adhesion of blood plasma than a pristine PES membrane. The results also unveiled that PVP-k30/NCs improved the surface properties of the membrane and the urea and creatinine removal increased to 72% and 75% than pure PES membranes. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 513-525, 2019.

Prevalence of diabetic comorbidities and knowledge and practices of foot care among diabetic patients: a cross-sectional study.

BACKGROUND: Diabetes mellitus with comorbid complications constitute a major public health problem worldwide. The aim of this study was to evaluate the risk of comorbid complications with glycosylated hemoglobin levels and diabetes duration. Also assessed were patients' diabetic foot-care knowledge and practices. PATIENTS AND METHODS: This was a quasiexperimental study. A total of 360 type 2 diabetes mellitus patients were interviewed at a government health care center in Riyadh, Saudi Arabia. Diabetic complications and HbA1c-level data were collected from hospital records. A standard questionnaire was used to assess their diabetic foot-care knowledge and practice. RESULTS: Of the type 2 diabetes mellitus patients, 32.5% had highly uncontrolled glycosylated hemoglobin (HbA1c) levels (≥8.6%) and 62.8% had had diabetes >10 years. The patients had comorbid complications, such as hypertension (61.4%), dyslipidemia (58.6%), retinopathy (23.3%), heart disease (14.4%), and severe foot complications (3.9%). The majority of highly uncontrolled HbA1c-level patients had retinopathy (OR 8.90, P=0.0001), foot complications (OR 8.09, P=0.0001), dyslipidemia (OR 2.81, P=0.010), and hypertension (OR 2.0, P=0.028) compared to the controlled HbA1c-level (<7%) group. Patients with diabetes >10 years also had higher prevalence of foot complications (OR 2.92, P=0.0001), retinopathy (OR 2.17, P=0.011), and hypertension (OR 1.67, P=0.033). From patient responses, physicians examined only 34.2% of patient feet and 36.7% of patients received physicians advice for foot care. About 70% of patients had knowledge of diabetic foot care; however, only 41.7% of patients always examined their feet, 41.4% washed feet with warm water, 31.4% carefully dried between the toes, and 33.1% were using foot-moisturizing substances. CONCLUSION: The prevalence of comorbid complications was higher in the Saudi population compared to other international studies. Also, foot-care practice was not satisfactory. Therefore, there is need of improvement and increased awareness among physicians and patients to check regularly for proper care of the diabetic foot to avoid diabetic foot-related complications.

Electrospun nanofibers and spin coated films prepared from side-chain copolymers with chemically bounded platinum (II) porphyrin moieties for oxygen sensing and pressure sensitive paints.

Pressure sensitive paints (PSP) containing oxygen probes were primarily used to measure air pressure. In this perspective, a polymerizable methacrylate-derived tetraphenylporphinato platinum(II) (PtTPP-MA) monomer was copolymerized with acrylic/vinyl monomers to produce four different copolymers. Octafluoropentyl methacrylate (OCFPM) and pentafluorophenyl acrylate (PFPA) were used as fluorinated monomers. Methyl methacrylate (MMA) and styrene (S) were used as non-fluorinated monomers. The structures and physical properties of the polymers were confirmed by 1H NMR, 19F NMR, GPC, and DSC. Experimental conditions were optimized to get fine nanofibers. Pressure sensing electrospun membranes and spin coated films were fabricated. Nanofibers showed fast response and good sensitivity towards gaseous oxygen. The influence of types of substrate and polymer natures on response time, oxygen sensitivity, and pressure responses were deliberated. Among our synthesized copolymers, poly(PS-co-PFPA-co-OCFPM-co-PtTPPMA) (Polymer P3) showed fast response time and good pressure sensitivity both as spin coated films and nanofibers.

Synthesis of antibacterial poly(o-chloroaniline)/chromium hybrid composites with enhanced electrical conductivity.

Electrically conductive polyorthochloroaniline/chromium nanocomposites (POC/Cr NCs) were prepared by in situ chemical oxidative polymerization of orthochloroaniline in the presence of Cr nanoparticles (Cr NPs). The load percentage of Cr nanofiller was varied in POC matrix to investigate the effect of Cr nanoparticles on the properties of the nanocomposites. The composition, structure, and morphology of POC and its composites were examined by Scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-visible spectroscopic analysis. The antibacterial potential of POC and its composites was evaluated by the disc diffusion method against Escherichia coli and Bacillus subtilis. The results showed the improved antibacterial potential with the increase in the load percentage of nanofiller. The electrical conductivity of polymer and its composites was measured and correlated with the load percentage. The results showed that electrical conductivity of the composites was enhanced with the increase in load percentage of Cr nanoparticles.

Synthesis of ethylene diamine-based ferrocene terminated dendrimers and their application as burning rate catalysts.

Ferrocene-based derivatives are widely used as ferrocene-based burning rate catalysts (BRCs) for ammonium perchlorate (AP)-based propellant. However, in long storage, small ferrocene-based derivatives migrate to the surface of the propellant, which results in changes in the designed burning parameters and finally causes unstable combustion. To retard the migration of ferrocene-based BRCs in the propellant and to increase the combustion of the solid propellant, zero to third generation ethylene diamine-based ferrocene terminated dendrimers (0G, 1G, 2G and 3G) were synthesized. The synthesis of these dendrimers was confirmed by 1H NMR and FT-IR spectroscopy. The electrochemical behavior of 0G, 1G, 2G and 3G was investigated by cyclic voltammetry (CV) and the burning rate catalytic activity of 0G, 1G, 2G and 3G on thermal disintegration of AP was examined by thermogravimetry (TG) and differential thermogravimetry (DTG) techniques. Anti-migration studies show that 1G, 2G and 3G exhibit improved anti-migration behavior in the AP-based propellant.

Sustained release of hydrophilic drug from polyphosphazenes/poly(methyl methacrylate) based microspheres and their degradation study.

Drug delivery system is referred as an approach to deliver the therapeutic agents to the target site safely in order to achieve the maximum therapeutic effects. In this perspective, synthesis of three new polyphosphazenes and their blend fabrication system with poly(methyl methacrylate) is described and characterized with (1)H NMR, (31)P NMR, GPC and DSC. Furthermore, these novel blends were used to fabricate microspheres and evaluated for sustain release of hydrophilic drug (aspirin as model drug). Microspheres of the two blends showed excellent encapsulation efficacy (about 93%), controlled burst release (2.3% to 7.93%) and exhibited sustain in vitro drug release (13.44% to 32.77%) up to 218 h. At physiological conditions, the surface degradation of microspheres and diffusion process controlled the drug release sustainability. Furthermore, it was found that the degree of porosity was increased with degradation and the resulting porous network was responsible for water retention inside the microspheres. The percentage water retention was found to be interrelated with degradation time and percentage drug release.

Review on synthesis of ferrocene-based redox polymers and derivatives and their application in glucose sensing.

The interest in glucose biosensors persisted over many years and persistent efforts have been made to develop long term stable glucose biosensors with precision, smart analytical performance, good linearity and resistance to communal interferences. In this regard, ferrocene-based polymers and derivatives (FBPDs) for the development of glucose biosensor (GBs) as redox mediators have acquired utmost attention of the scientists, especially in the second generation biosensors, as a large number of innovative molecules have been synthesized. Most of the FBPDs are considered as active components in the development of GBs, due to their ease of modification, biocompatibility, stability, large surface area, good electrical conductivity and especially excellent redox properties. This review provides a brief description of synthesis, analytical performance and glucose sensing application of ferrocene-based dendrimers, polythiophenes, polypyrroles, polyethylenimine, chitosan and carbon nano tubes (CNTs). Moreover, the analytical performance of ferrocene-based glucose biosensors (FBGBs) is summarized and the problems associated with the construction of GBs and the future trends are discussed.

Immunophenotyping of Non-Hodgkin's lymphomas in Sudan.

INTRODUCTION: Non-Hodgkin's lymphomas (NHLs) are heterogeneous group of malignant lymphoproliferative disorders. STUDY OBJECTIVES: This was a retrospective study aimed to classify NHLs into B cell and T cell types; in addition to demonstrate the histological patterns and correlate it with gender, age and site of the biopsy. METHODS: The study was conducted in Histopathology Department, National Heath Laboratory, during the period 2007-2010. Formalin fixed paraffin wax embedded tissue blocks which were diagnosed as NHLs by routine Haematoxylin and Eosin (H&E) stain during the period 2000-2008 were used. Haematoxylin and Eosin (H&E) stain were done. Immunohistochemistry stains performed according to Dako cytomation protocol 2007. Lymphoid markers which were used in this study are CD45 (LCA), CD20 (B cell marker), CD3 (T cell marker), CD15 and CD 30. Epithelial marker which was used is CK MNF116. The total number of samples collected was 66; two of them were excluded because of poor processing. Another two specimens were excluded because they are non-reactive with lymphoid markers. The remaining 62 specimens were confirmed to be NHLs and classified into B cell and T cell types. RESULTS: The study showed that B cell NHLs represented 87.1% while T cell NHLs were 12.9%. The Male: Female ratio was 1.6:1. The major affected age group was (47-67) years (38.1% of all specimens). The most frequent histological grade was intermediate grade NHLs (27% of all specimens). The most common site of NHLs in this study is the lymph node (40% of all specimens) followed by stomach (19.4%). CONCLUSION: Extranodal locations are the most common sites affected with T cell NHLs. In conclusion; this study confirmed the fundamental role of immunohistochemistry in diagnosis and classification of NHLs.

Statistical and Graphical Assessment of Circumferential and Radial Hardness Variation of AISI 4140, AISI 1020 and AA 6082 Aluminum Alloy.

Hardness homogeneity of the commonly used structural ferrous and nonferrous engineering materials is of vital importance in the design stage, therefore, reliable information regarding material properties homogeneity should be validated and any deviation should be addressed. In the current study the hardness variation, over wide spectrum radial locations of some ferrous and nonferrous structural engineering materials, was investigated. Measurements were performed over both faces (cross-section) of each stock bar according to a pre-specified stratified design, ensuring the coverage of the entire area both in radial and circumferential directions. Additionally the credibility of the apparatus and measuring procedures were examined through a statistically based calibration process of the hardness reference block. Statistical and response surface graphical analysis are used to examine the nature, adequacy and significance of the measured hardness values. Calibration of the apparatus reference block proved the reliability of the measuring system, where no strong evidence was found against the stochastic nature of hardness measures over the various stratified locations. Also, outlier elimination procedures were proved to be beneficial only at fewer measured points. Hardness measurements showed a dispersion domain that is within the acceptable confidence interval. For AISI 4140 and AISI 1020 steels, hardness is found to have a slight decrease trend as the diameter is reduced, while an opposite behavior is observed for AA 6082 aluminum alloy. However, no definite significant behavior was noticed regarding the effect of the sector sequence (circumferential direction).

Determination of vancomycin in human plasma using high-performance liquid chromatography with fluorescence detection.

A high-performance liquid chromatographic (HPLC) method with fluorescence detection for the quantification of vancomycin in human plasma was developed and validated. The method includes an extraction of vancomycin by deproteinization with acetonitrile. The analyses were carried out at 258 nm as the emission wavelength while exciting at 225 nm on a reversed-phase column (30 cm x 4 mm i.d. x 10 microm Waters Associates microBondapak C18) using a mobile phase composed of methanol and phosphate buffer at pH 6.3. Vancomycin was quantitatively recovered from human plasma samples (>96%) with high values of precision. The separation was completed within 27 min. The calibration curve was linear over the range from 5 to 1,000 ng/mL with the detection and quantification limits of 2 ng/mL and 5 ng/mL, respectively. This method is suitable for the routine assay of plasma samples.