Green Method for Evaluation of Marbofloxacin Tablets by HPLC and Evaluation of Interchangeability With UV and Turbidimetric Methods

BACKGROUND

Marbofloxacin (MAR) is a veterinary antimicrobial, marketed in injectable solution, oral suspension, and tablets. MAR has no monograph for tablet evaluation in official compendiums. High Performance Liquid Chromatography (HPLC) methods present in the literature for evaluating MAR in tablets do not follow the principles of green and sustainable analytical chemistry.

OBJECTIVE

A green, clean, and sustainable method by HPLC was developed and validated to evaluate the content and stability of MAR in tablets, in addition to comparing it with other methods available in the literature.

METHOD

A C8, 5 µm, 4.6 × 150 mm (ACE®) column, purified water with 0.2% formic acid-ethanol (70:30, v/v) as the mobile phase, and a flow rate of 0.7 mL/min at 296 nm were used.

RESULTS

The method was linear over a concentration range of 1-10 μg/mL, selective for tablet matrix and forced degradation, precise with relative standard deviations (RDS) less than 5%, accurate with recovery of 99.99%, and robust to changes in the mobile phase, flow rate, wavelength, equipment, and column brand. The retention time for MAR was approximately 3.1 min.

CONCLUSIONS

The method can be used in routine analysis of MAR in tablets in chemical-pharmaceutical laboratories. Furthermore, it can be used to verify the stability of MAR-based products and proved to be interchangeable with spectrophotometric method in the UV region and turbidimetric microbiological method.

HIGHLIGHTS

A green method for evaluation of marbofloxacin tablets by HPLC was developed and validated. Additionally, it has been shown to be interchangeable with UV and turbidimetric methods.

Moxifloxacin: Physical-chemical and Microbiological Analytical Methods in the Context of Green Analytical Chemistry

Moxifloxacin (MOX) is a fourth-generation fluoroquinolone used in the form of tablets, infusion solutions and ophthalmic solutions. It does not have a physical-chemical or microbiological analytical method described in an official compendium. However, the literature shows some analysis methods for pharmaceuticals and biological matrices. In this context, the objective is to show the analytical methods present in the literature for the investigation of MOX by physical-chemical and microbiological techniques, as well as discussing them according to the requirements of current pharmaceutical analyses and green analytical chemistry. Among the physical-chemical methods present in the literature for MOX evaluation, 33% are HPLC, 21% are UV-Vis and 17% are capillary electrophoresis. On the other hand, among the microbiological methods, all of them are based on diffusion in agar. There is still scope in the literature to incorporate new and improved analytical methods for MOX evaluation, which adopt the concepts of green and sustainable analytical chemistry, either by using less (or not using) toxic organic solvents, reducing waste generation or even reducing the analysis time according to the intended objectives.

Cyclodextrin inclusion complex of a multi-component natural product by hot-melt extrusion

This study aimed to investigate whether hot-melt extrusion (HME) processing can promote molecular encapsulation of a multi-component natural product composed of volatile and pungent hydrophobic substances (ginger oleoresin (OR)) with cyclodextrins. 6-Gingerol and 6-shogaol, the biomarkers of ginger OR, were quantified by HPLC. Phase-solubility studies were performed using β-cyclodextrin (βCD) and hydroxypropyl-β-cyclodextrin (HPβCD) for ginger OR complexation. Solid complexes were then prepared by thermal (HME)- and solvent (slurry (SL))-based methods. Morphology, thermal behavior, solubility, in vitro dissolution, and in vivo anti-inflammatory activity were evaluated. HPβCD gave rise to AL-type complexes with ginger OR, whereas βCD led to materials with limited solubility. Ginger OR was complexed with HPβCD by HME without significant change in gingerol and shogaol content. Additionally, thermogravimetric analysis (TGA) suggested higher volatile retention in HME complexes than in SL ones. Shogaol and gingerol solubility and dissolution significantly increased from SL and HME complexes compared with ginger OR. In turn, 1:2 OR/HPβCD HME complex showed higher 6-shogaol solubility than SL, associated with a gradual release. The carrageenan-induced pleurisy test showed that the anti-inflammatory activity of ginger OR was maintained after complexation with HPβCD. The complexes significantly decrease the levels of IL-1β and inhibit cell migration. HME complex showed performance equivalent to the positive control and superior to the SL material. Taken together, these results indicate that HME can be useful for promoting the molecular encapsulation of complex natural products that contain volatile and thermolabile substances. HME complexes showed better in vivo and in vitro performance than complexes prepared using the solvent-based method.

A new, ecological and stability-indicating method by HPLC for the quantification of moxifloxacin in tablets

Introduction:

A new, ecological, and stability-indicating method by HPLC was developed for the quantification of moxifloxacin in tablets. A C18 column at 33°C, purified water acidified with 0.2% phosphoric acid and ethanol (74:26,v/v), flow rate at 1.0 mLmin-1, injection volume of 5 µL, and detection at 290 nm was used.

background:

Moxifloxacin (MOX), a fluoroquinolone antimicrobial, does not present a physical-chemical analytical method for tablets form described in an official compendium. On the other hand, the literature shows some methods for evaluating MOX by HPLC. However, they bring opportunities for improvement.

Method:

The method was linear (2-12 μgmL-1), selective, accurate (100.86%), precise (RSD<2%), and robust.

Result:

The retention time for moxifloxacin in tablets was approximately 4.4 minutes.

method:

A Inertsil ODS-4 (150 x 4.6 mm, 5 μm, GL SciencesTM) column at 33 °C, purified water acidified with 0.2 % phosphoric acid and ethanol (74: 26, v/v) as mobile phase, flow rate at 1.0 mL min-1, injection volume of 5 µL and detection at 290 nm were used.

Conclusion:

To sum up, a method based on the principles of green analytical chemistry was successfully developed and validated for the quantification of moxifloxacin in tablets.

other:

Keywords: HPLC, green analytical chemistry, method validation, tablets, fluoroquinolone, moxifloxacin.

Overview of Analytical Methods for Evaluating Tinidazole

BACKGROUND

Tinidazole (TIN) has amoebicidal, giardicidal, antifungal, and antimicrobial activities. It is marketed in the form of tablets. Analytical methods to assess the quality of TIN-based products are essential for correct pharmacotherapy.

OBJECTIVE

The objective of this review is to show an overview of the existing analytical methods for evaluating TIN, according to the quality control (QC) analysis routine and green analytical chemistry (GAC).

RESULTS

Official compendia show a method for evaluating TIN in tablets by nonaqueous titration, which has limitations (materials on the mg scale using solvents considered not recommended and harmful). The literature shows some analytical methods for evaluating TIN, both physicochemical and microbiological. The most used physicochemical method is UV (41%), and second is HPLC (28%). Among the microbiological methods, agar diffusion and turbidimetric methods are equally divided. The most studied matrix is TIN tablets (73%), and the most used solvent is methanol.

CONCLUSIONS

The literature shows space for the development of analytical methods according to GAC for evaluating TIN, optimizing time, resources, and materials, reducing waste generation, and opting for less aggressive reagents, solvents, and diluents.

HIGHLIGHTS

This review shows the status of analytical methods, both physicochemical and microbiological, for the analysis of TIN in pharmaceutical matrix, in the context of routine analysis of the chemical-pharmaceutical industries and of GAC.

Review of Analytical Methods for Evaluating Azithromycin in the Context of Green Analytical Chemistry

BACKGROUND

Azithromycin (AZT) is an antimicrobial available in different pharmaceutical forms and many people can have access to this medicine. Therefore, the existence of adequate and reliable analytical methods for evaluating the quality of AZT and AZT-based products is essential.

OBJECTIVE/METHODS

The purpose of this review is to discuss the analytical methods for evaluating AZT present in the literature and official compendia in the context of Green Analytical Chemistry (GAC).

RESULTS

Among the methods found in the literature for evaluating AZT, the most used method is HPLC (62%) followed by TLC (14%) and the microbiological method by agar diffusion (14%). Even pharmacopoeias recommend the analysis of AZT by HPLC or agar diffusion. Acetonitrile and methanol account for 35% of the most used solvents in the analyses, followed by buffer.

CONCLUSION

AZT lacks analytical methods in the context of GAC. Both physical-chemical and microbiological methods can contemplate the environmentally friendly way to analyze AZT and AZT-based products, depending only on the chosen conditions. Ethanol, purified water, acetic acid instead of methanol, acetonitrile, buffer, formic acid in the physical-chemical methods are excellent alternatives. However, in the microbiological method, turbidimetry is a great option instead of agar diffusion.

Tools to Evaluate the Eco-efficiency of Analytical Methods in the Context of Green and White Analytical Chemistry: A Review

BACKGROUND

The release of a product in the consumer market requires an analysis by quality control. This sector makes use of reliable analytical methods, by high performance liquid chromatography (HPLC), spectrophotometry in the ultraviolet and visible regions (UV-Vis), spectrophotometry in the infrared region (IR) or thin layer chromatography (TLC), for example, to reach a result. The analysis conditions of most of these analytical methods currently still use toxic reagents, generate a greater amount of waste, sample preparation has more steps, the need for instrumentation and consumables in greater quantity, generating a cost and impact on health and the environment greater than if there were adoption of the Green Analytical Chemistry (GAC) and the White Analytical Chemistry (WAC).

OBJECTIVE/METHODS

The objective of this review is to show the relationship of analytical choices for current pharmaceutical analyzes with the GAC and the WAC.

RESULTS

Analytical methods can be evaluated for greenness and whiteness using tools such as the National Environmental Method Index (NEMI), Eco-Scale Assessment (ESA), Analytical Greenness Metric (AGREE) and Green Analytical Procedure Index (GAPI).

CONCLUSION

The use of NEMI, ESA, AGREE and GAPI tools brings the objective evidence needed to discuss the greenness and whiteness of an analytical method, leaving the subjective level. Furthermore, semi or quantitative data facilitate the choice of an analytical method and its conditions, when the target is the concern with eco-efficiency.

Fast and new microbiological method for evaluating the potency of marbofloxacin-based tablets

Background

Marbofloxacin (MAR) is an antimicrobial belonging to the fluoroquinolone class and is marketed in the form of tablets. It does not present a microbiological monograph in official compendia to evaluate the potency of the final product. Furthermore, the literature is scarce in this context.

Objective

The objective is to develop and validate a microbiological method by turbidimetry to evaluate the potency of MAR-based tablets, based on the principles of green analytical chemistry.

Methods

Purified water and ethanol (90:10, v/v) as diluents to prepare the MAR solutions at concentrations of 0.25; 0.8 and 2.56 µg/mL, BHI broth as culture media, E. coli ATCC 25922 at 10% and incubation in a shaker at 37 °C for 4 hours were used in the method.

Results

The method was linear in the range of 0.25 to 2.56 µg/mL, selective against the sample adjuvants, precise (intraday RSD 2.26%, interday RSD 3.49% and between analysts RSD 3.59%), accurate with recovery of 100.20% and robust against changes in culture medium volume in tube, shaker rotation and incubation temperature in the shaker. The potency of MAR tablets was 96.98% using the proposed method.

Conclusions

The turbidimetric method developed is a new, fast and optimized option to the routine quality control of MAR in tablets, since it allows the evaluation of the drug's potency in the final product and can be used to complement the results of the physico-chemical analysis, in addition to being a green and sustainable alternative.

Highlights

The work shows an ecological and green alternative to the routine microbiological pharmaceutical analysis of MAR tablets.

Analytical Aspects for Evaluation of Pharmaceutical Products: A MiniReview

Background:

The pharmaceutical industry is in constant development, aiming to increase its portfolio, optimizing time, product quality and efficacy along with patient safety. The main goal of developing and validating an analytical method is to achieve a balance between costs and risks within the wide array of technical possibilities in order to assure that the method is capable of meeting its expectations, ensuring effective quality control.

Objective:

The objective of this mini-review is to discuss the analytical aspects of development and validation for analysis of pharmaceutical products, focusing on the complete evaluation package in a systematic way to demonstrate the optimal performance of the method.

Methods/Results:

Validation results are obtained following strict protocols, typically starting with the assessment of selectivity/specificity parameters, followed by parameters such as linearity and precision. Moreover, accuracy, detection limit, quantification limit and method robustness are also evaluated.

Conclusion:

This paper may serve as a guide for the pharmaceutical-chemical laboratory, conceptualizing quality and current analytical needs, according to Green Analytical Chemistry, for the development and validation of reliable methods, ensuring clarity to the analyst and assisting in decision making.

Status of Physicochemical and Microbiological Analytical Methods of Gatifloxacin: A Review

Background

Gatifloxacin (GAT), an antimicrobial of the fourth generation of fluoroquinolones, has a broad spectrum of action with activity against Gram-positive and Gram-negative, aerobic and anaerobic organisms, including mycobacteria.

Objective

The objective of this review is to discuss about (i) characteristics, (ii) properties, and (iii) analytical methods of gatifloxacin.

Results

Among the methods described in the literature for the evaluation of GAT, the most frequent was HPLC (50%) for both the analysis of pharmaceutical and biological matrixes. GAT has no monograph described in official compendia. Methods for evaluating GAT in pharmaceutical matrixes were the most found in the literature, 79%. Acetonitrile (42%), methanol (20%), and buffer solution (16%) were the most used diluents. GAT, being an antimicrobial, must be analyzed by physical-chemical and microbiological methods, since the evaluation of potency is essential. In this context, the literature is scarce (4%).

Conclusions

There is a gap in the literature for environmentally friendly methods for evaluating GAT. Faster, more optimized and dynamic microbiological methods, as well as physicochemical methods, use less aggressive solvents with fewer steps and less waste. Currently, pharmaceutical analyses require reliable analytical methods, but also safe for both the analyst and the environment.

Highlights

This review shows the status of analytical methods, both physicochemical and microbiological, for the analysis of GAT in pharmaceutical and biological matrixes, also addressing its context in green and sustainable analytical chemistry.

An Overview of Analytical Methods for the Quantification of Marbofloxacin in Pharmaceutical, Biological and Food Matrices

BACKGROUND

Marbofloxacin (MAR), a second-generation fluoroquinolone, is used in veterinary medicine in the form of tablets. It has a broad spectrum of action, low toxicity, and limited development of bacterial resistance. The analytical methods available in the literature become more important since MAR in tablets does not have a monograph in official compendiums.

OBJECTIVE

Thus, the purpose of this review is to display them according to the analyzed matrix and place them according to the conditions used in the scope of green analytical chemistry, in addition to discussing possible gaps and opportunities for the development of new methods.

RESULTS

MAR, being an antimicrobial, presents both physical-chemical (93%) and microbiological (7%) methods in the literature. Among the methods found, 53% are for analysis of food matrices using preferably HPLC and TLC-MS. 27% are for analysis of biological matrices and 20% are for analysis of pharmaceutical matrices, and in both HPLC is preferably used.

CONCLUSIONS

Therefore, there is still a gap in the literature in relation to other options of analytical methods for the analysis of MAR, which are faster, such as microbiological turbidimetry, sustainable, such as miniaturized methods, and ecologically correct, such as those that do not usetoxic organic solvents.

HIGHLIGHTS

A review of the status of analytical methods available in the literature for assessing the quality of MAR and MAR-based products were exhibited and discussed, as well as new opportunities for analysis according to green analytical chemistry.

Miniaturized Microbiological Method to Determine the Potency of Rifaximin in Tablets

BACKGROUND

Rifaximin, a semi-synthetic antimicrobial, does not present microbiological method described in official compendia, and there is a lack of literature on this topic. The quality control of antimicrobials is extremely important to evaluate the real potency of pharmaceutical products.

OBJECTIVE

A miniaturized turbidimetric method for determining the potency of rifaximin in tablets was developed and validated by turbidimetry, according to the international guidelines.

METHOD

Escherichia coli ATCC 10536 IAL 2393, brain heart infusion (BHI) broth, inoculum at 8%, rifaximin in purified water with 20% ethanol at 5, 10, and 20 μg/mL and 530 nm were used.

RESULTS

The method was considered selective for rifaximin, as the adjuvants did not show activity; linear with correlation coefficients 0.9998 for standard and 0.9999 for sample; accurate with 99.73% recovery; precise with RSD less than 3%; and robust in the face of small variations in (i) rifaximin volume, (ii) proportion of ethanol, (iii) inoculum volume.

CONCLUSIONS

The method is considered adequate and safe to evaluate the potency of rifaximin in tablets, contemplating speed, low cost, low waste generation, and ease of operation.

HIGHLIGHTS

This work usescurrent, sustainable, and green analytical chemistry and can be used in the routine analyses of rifaximin by laboratories and the pharmaceutical industry around the world.

Eco-Friendly Pharmaceutical Analysis of Rifaximin in Tablets by HPLC-MS and Microbiological Turbidimetry

Rifaximin, an antimicrobial used for the treatment of various diseases, lacks analytical methods in official compendia for evaluation of the final product. This paper presents an eco-friendly protocol for rifaximin tablets by high performance liquid chromatography coupled with mass spectrometry (HPLC-MS). The method was completely validated according to the International Conference on Harmonization guidelines and developed following the concept of Quality by Design. The separation was achieved using a C18 column, purified water +0.1% glacial acetic acid and ethyl alcohol, 52:48 (v/v), as mobile phase, 0.9 mL min-1 at 290 nm and ambient room temperature. Mass spectral analyses were performed using electrospray ionization (ESI) ion source and ion trap mass analyzer. The method was linear over the concentration range of 5-50 μg mL-1. The sample was subjected to acidic, basic, neutral, oxidative and photolytic degradation. Degradation products did not interfere in the quantification of the rifaximin, so the method can be considered indicative of stability. Degradation products were also evaluated individually by microbiological method using Escherichia coli. The validated method could be used promisingly as green analytical strategies for detection and quantification of rifaximin in tablets.

Short-Stability Study of Rifaximin-Based Samples

BACKGROUND

Rifaximin is an oral antimicrobial with a daily dose ranging from 600 to 800 mg. It is classified as Class IV in the Biopharmaceutic Classification System. Thus, rifaximin-based samples were developed by complexation to β-cyclodextrin using a phase solubility diagram, and malaxation and decreasing particle size using wet milling.

OBJECTIVE

Concomitant to the pharmaceutical technology, a stability studywas undertaken with the objective of verifying the integrity of the drug.

METHODS

The stability of the new samples were studied for 6 months, without interruption, under controlled conditions of temperature and humidity in a climatic chamber. They were analyzed simultaneously by HPLC and microbiological turbidimetry at zero, 3, and 6 months.

RESULTS

Two of the samples follow second reaction order and one follows zero reaction order. Microbiological analysis proved to be important in assessing the potency of rifaximin in one of the samples, and its results were more consistent than the results by HPLC.

CONCLUSIONS

The rifaximin-based samples were stable under controlled temperature and humidity conditions and the physical-chemical and microbiological methods were able to evaluate their behavior during the 6-month study.

HIGHLIGHTS

It is worth considering the development of these products, since the design process of formulation and pharmaceutical technology is financially more attractive than the development of new drugs that require high levels of investment in research and development, innovation of public policies, and regulatory actions.

A Clean, Sustainable and Stability-Indicating Method for the Quantification of Ceftriaxone Sodium in Pharmaceutical Product by HPLC

Ceftriaxone sodium is a widely used antimicrobial, which is only available as a lyophilized powder. The presence of methods for evaluating the quality of this product is very important and helps to ensure its effectiveness, in addition to contributing to the fight against bacterial resistance. Therefore, a clean and sustainable high-performance liquid chromatography (HPLC) method has been developed for evaluating ceftriaxone stability in pharmaceutical product. A Zorbax SB C18 (150 × 4.6 mm, 5 μm) column was maintained at 25°C; the mobile phase consisted of purified water acidified with 0.2% orthophosphoric acid and ethanol (87: 13, v/v) at a flow rate of 0.9 mL min-1. The detection wavelength was set at 260 nm. The method was linear over a concentration range of 20-120 μg mL-1, precise with relative standard deviations <2%, robust in the event of minor changes to the original method conditions, accurate with recovery between 98% and 102% and specific to degradation products. The retention time for ceftriaxone sodium was ~4.6 minutes. This work shows an ecologically correct option by HPLC method for the evaluation of ceftriaxone sodium in pharmaceutical product, as well as its stability, which addresses the requirements of the current green and sustainable analytical chemistry.

A New and Ecological Method to Quantify Vancomycin in Pharmaceutical Product by Infrared Spectrometry

Vancomycin, an antimicrobial, does not present quantitative method by infrared spectrometry in the literature for the evaluation of a pharmaceutical product. This technique is considered a clean alternative because in the main, there is no solvent involved and the generation of waste is reduced. So, the aim of this study was to develop and validate a new, ecological, low cost and fast method by infrared spectrometry using KBr and band between 1450–1375 cm–1. It was linear in the range of 1.0–2.0 mg/150 mg, with a correlation coefficient of 0.9994. Selective when the spectra of vancomycin reference and sample were compared. Precise by repeatability (2.29%) and intermediate precision (3.12%). Accurate with average recovery of 99.37% and robust when strength and compression time of the pellets and KBr brand were varied. Considering all the methods found in literature, there is not one using infrared spectrometry for quantitative purpose, so the method developed and validated could be considered an innovation and clean alternative. This is due to the fact that it is fast, easy to handle, low cost, and non-toxic as well as generating minimal waste. The method can be applied in the routine analysis of vancomycin dosage form and is an important option for the current and sustainable pharmaceutical analysis.

A New and Ecological Method to Quantify Vancomycin in Pharmaceutical Product by Infrared Spectrometry

Vancomycin, an antimicrobial, does not present quantitative method by infrared spectrometry in the literature for the evaluation of a pharmaceutical product. This technique is considered a clean alternative because in the main, there is no solvent involved and the generation of waste is reduced. So, the aim of this study was to develop and validate a new, ecological, low cost and fast method by infrared spectrometry using KBr and band between 1450-1375 cm-1. It was linear in the range of 1.0-2.0 mg/150 mg, with a correlation coefficient of 0.9994. Selective when the spectra of vancomycin reference and sample were compared. Precise by repeatability (2.29%) and intermediate precision (3.12%). Accurate with average recovery of 99.37% and robust when strength and compression time of the pellets and KBr brand were varied. Considering all the methods found in literature, there is not one using infrared spectrometry for quantitative purpose, so the method developed and validated could be considered an innovation and clean alternative. This is due to the fact that it is fast, easy to handle, low cost, and non-toxic as well as generating minimal waste. The method can be applied in the routine analysis of vancomycin dosage form and is an important option for the current and sustainable pharmaceutical analysis.

An Ecological and Miniaturized Biological Method for the Analysis of Daptomycin Potency

BACKGROUND

Physicochemical and microbiological methods are found in the literature for the analysis of daptomycin, an antimicrobial.

OBJECTIVE

This paper brings a miniaturized turbidimetric microbiological method for analysis of daptomycin in lyophilized powder.

METHODS

The method was performed using 96-well microplates, 4-h incubation, 2, 4 and 8 μg/mL, 7% Staphylococcus aureus ATCC 6538 IAL 2082, and BHI broth.

RESULTS

Linearity was proven by obtaining analytical curves with a correlation coefficient greater than 0.99 and statistical evaluation by ANOVA. The method was also selective, since the standard and sample analytical curves were parallel, proving that the excipient does not interfere with daptomycin analysis. Intraday, interday and inter-analyst precision presented RSDs of 2, 2.27, and 1.08%, respectively. Accuracy was assessed by the recovery test, where known quantities of standard solution are added to the sample and an average recovery value of 100.73% (RSD = 0.71%) was obtained. The present method was robust when minor changes were made in the parameters of used antimicrobial volume, inoculum volume and incubation time.

CONCLUSIONS

This work is an innovative and ecological proposal and has advantages such as (i) less waste generation, (ii) miniaturized quantities of sample, culture media and inoculum, (iii) no need to use formaldehyde as in the traditional turbidimetric method, (iv) lower volume of glassware used and (v) shorter incubation time compared to other methods as agar diffusion requiring approximately 24 h.

HIGHLIGHTS

This work is focuses on a current, innovative and sustainable theme for pharmaceutical analysis around the world.

Turbidimetric Method: A Multi-Advantageous Option for Assessing the Potency of Ceftriaxone Sodium in Powder for Injection

BACKGROUND

Ceftriaxone sodium, an antimicrobial used in parenteral form, does not have a microbiological method by turbidimetry described in the literature. For drugs from antimicrobial class, the existence of a microbiological method for assessing their potency is essential. Not only are the results from the physical-chemical methods enough, but microbiological analyzes are also necessary.

OBJECTIVE AND METHODS

Thus, this paper reports the development and validation of an efficient, accurate, reproducible, fast, and low-cost microbiological assay by turbidimetry to quantify ceftriaxone sodium in powder for injection. Water was used as the diluent to prepare the ceftriaxone solutions. BHI broth as used as culture media for the growth of the S. aureus ATCC 6538 at 9%.

RESULTS

The method was linear in the range of 100-196 µg/mL, selective against the sample adjuvants and the forced degradation test, precise (intraday RSD 4.53%, interday RSD 3.85% and between analysts tcalculated 0.14 < 2.23 tcritical), accurate with recovery of 100.33% and robust against minor changes in the volume of culture medium used, wavelength, incubation time, and inoculum concentration.

CONCLUSIONS AND HIGHLIGHTS

The turbidimetric method developed in this paper is a convenient and valuable alternative to the routine quality control of ceftriaxone sodium in powder for injection, since it allows a reliable quantification and can be used to complement the physical-chemical analysis.

Determination of dexamethasone acetate in CETETH 20-based in liquid crystalline systems using HPLC

Dexamethasone acetate (DEX), a potent anti-inflammatory, is used primarily in the treatment of inflammatory and autoimmune diseases. It was incorporated in CETETH 20 (polyoxyethylene 20 cetyl alcohol)-based liquid crystalline systems to enhance the purpose of the drug. Concomitant with the pharmaceutical technology performed, a HPLC method was developed and validated for the quantification of dexamethasone acetate in CETETH 20-based liquid crystalline systems for the evaluation of the drug in the new matrix. The method was performed using a C18 column with acetonitrile:methanol:water (35:35:30, v/v/v) as the mobile phase at a flow rate of 0.8 mL min^-1 at 239 nm. The method was linear in the range of 1-25 μg mL^-1 ; the limit of quantification and limit of detection were 0.05 and 0.16 μg mL^-1 , respectively; the accuracy of the method was 99.92% (relative standard deviation < 1%), and it presented intra-day and inter-day precision with deviations less than 1%. In this context, the method was successfully used to determine the incorporation efficiency of DEX in CETETH 20-based liquid crystalline systems and can be easily used by pharmaceutical companies and laboratories around the world.

Cephalothin: Review of Characteristics, Properties and Status of Analytical Methods

BACKGROUND

Cephalothin (CET), a first generation cephalosporin, is the most efficient cephalosporin against resistant microorganisms. Many studies found in literature and pharmacopeias proposes analytical methods and, as most commonly, HPLC and microbiological assays.

OBJECTIVE

This paper shows a brief review of analytical method to quantify CET with a green analytical chemistry approach.

METHODS

The research data were collected from the literature and official compendia.

RESULTS

Most of the analytical methods to determine CET were performed by HPLC and agar diffusion in pharmaceuticals, blood, urine or water. Other analytical methods were found, as UV, Vis, iodometry, fluorimetry, IR/Raman, electrochemical among others, but, in less quantity. One important aspect is that these methods use organic and toxic solvents like methanol and acetonitrile, and only about 4% of the methods found uses water as solvent.

CONCLUSIONS

In this way, researches about analytical methods focused on green analytical chemistry for CET are of great importance and very relevant to optimize its analysis in pharmaceutical industries and to guarantee the quality of the product. More than just the development of new techniques it is possible to enhance of the ones that already exists applying the green analytical chemistry principles. In this way, it will be possible to reduce the environment impacts caused by these analytical procedures.

HIGHLIGHTS

This work shows a brief review of literature and pharmacopeias of analytical methods to quantify CET. Its quality control can be updated to meet the needs of current analytical chemistry and to fit into sustainable and eco-friendly analyzes.

Turbidimetric Method: A New, Ecological, and Fast Way to Evaluate of Vancomycin Potency

Background

Vancomycin, an antimicrobial, has many microbiological methods in literature, but it was not found any that follows the green chemistry principles.

Objective

The aim of this work was to develop and validate a new microbiological analytical method with a green view to determine the vancomycin potency in lyophilized powder using less quantity of diluents and culture medium, minimizing the costs and reducing the time of analysis.

Methods

The objective will be achieved using the microbiological method by turbidimetry.

Results

Water was used as the diluent to prepare the vancomycin solution. BHI broth as used as culture media for the growth of the S. aureus ATCC 25923. The method was linear in the range of 30, 39 and 50.7 µg/mL. It was selective, with vancomycin reference and sample absorbance values very similar. The precision of the method was proved at intraday (RSD 4.42 %), interday (RSD 3.56 %) and intermediate levels (RSD 2.03%). It was accurate with mean recovery of 100.71 % and robust when changes were performed in three parameters of the method and analyzed by the F-Test and t-Test.

Conclusions

The method for evaluating the potency of vancomycin in pharmaceutical product was successfully developed and validated.

Highlights

The method can be applied to routine quality control of vancomycin product as an alternative that contemplates the green analytical chemistry and the current pharmaceutical analyzes.

A Review of Analytical Methods for the Determination of Hypericin in Foods, Herbal, Biological and Pharmaceutical Matrices

Aims:

A review of analytical methods for the determination of hypericin in foods, herbal, biological and pharmaceutical matrices.

Background:

Hypericin (HYP) is a naturally-occurring pigment obtained from some plants of the genus Hypericum. Although HYP has been known for many years, it has recently attracted attention due to its varied biological properties, such as anti-inflammatory and antidepressant activity and it is also an efficient photosensitizer.

Objective:

The objective of this review is to provide insights into the physicochemical properties of HYP, as well as to report the analytical methods existing in the literature and official compendia for different matrices.

Methods:

The survey data were collected by Google Scholar® and Scopus® using keys terms.

Result:

Analytical methods involving HYP are mainly concerned with the quality control of pharmaceutical preparations, foods, beverages, biological samples and drug delivery systems using different types of analysis methods. Some difficulties have also been identified due to the physicochemical properties of HYP. It presents great solubility in alkaline solutions, organic bases and common polar organic solvents.

Conclusion:

It can be analyzed by thin layer chromatography, spectrophotometry in the ultraviolet region, but the most commonly used method is by HPLC. HYP presents monographs in the American, British and European Pharmacopoeias, however, the methods of analysis are not yet harmonized.

Current Status of Vancomycin Analytical Methods

BACKGROUND

The glycopeptide antibiotics are a class of antimicrobial drugs that are an important alternative for cases of bacterial infections resistant to penicillins, besides being able to be used to treat infections in people allergic to pencilin. They have great activity against Gram-positive microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA), by inhibiting the cell wall synthesis.

OBJECTIVE

There are many analytical methods in the literature for determination of antimicrobial glycopeptide vancomycin in different matrixes that are very effective; however, all of them use toxic solvents, contributing to the generation of waste, causing damage to the environment and to the operator, as well as increased costs of analysis.

RESULTS

The most prevailing method found was high performance liquid chromatography (HPLC), followed by microbiological assays and, in less quantity, spectrometric methods. The chromatographic methods use organic solvents that are toxic, such as acetonitrile and methanol, and buffer solutions, that can damage the equipment and the column. In the microbiological assays the disc diffusion methods are still in the majority. The spectrophotometric methods were based in the UV-Vis region using buffer solutions as a diluent.

CONCLUSIONS

All these methods can become greener, following green analytical chemistry principles, which could bring benefits both to the environment and the operator, and reduce costs.

HIGHLIGHTS

In this paper, a literature review regarding analytical methods for determination of vancomycin was carried out with a suggestion of greener alternatives.

Bioanalytical method by HPLC-FLD for curcumin analysis in supplemented athletes

In sports, curcumin, a substance derived from the rhizome of Curcuma longa (turmeric) plant with antioxidant effect 8 times greater than vitamin E, has attracted the attention of scientists because of its potent antioxidant action, since in athletes subjected to intense exercise the—endogenous mechanisms of neutralization of reactive species are saturated. However, the pharmacokinetic characteristics of curcumin do not favor its medicinal use due to its low absorption, accelerated metabolism and rapid systemic elimination. Thus, the determination of plasma levels in supplemented patients is a crucial step in their pharmacodynamic evaluation. Therefore, the objective of this work was to develop and validate an analytical method by HPLC-FLD for curcumin evaluation in plasma of supplemented athletes. Luna column (C18; 150 × 4 mm; 3 µm), acetonitrile: acetic acid pH 3.2 (45:55 to 60:40) as mobile phase, flow rate of 1 mL min⁻¹, excitation at 429/285 nm and emission at 529 nm and injection of 10 µL were the chromatographic conditions used. Plasma samples were extracted using ethylacetate and methanol (95: 5, 500 µL) and estradiol (30 µg mL⁻¹) as internal standard, with subsequent stirring (3 min) and centrifugation (8 min) (triple extraction). The organic fraction was evaporated under N₂ (20 min) and the dried residue reconstituted in acetonitrile. The method was linear between 44 and 261 ng mL⁻¹, showing intra-day (2.05.6%) and inter-day (4.0–5.1%) precision with accuracy and selectiveness (curcumin t_R = 8.7 min and internal standard t_R = 13.9 min with relative recovery of 83.2%). So, it can be successfully used for curcumin evaluation in plasma samples from supplemented athletes, as well as being an alternative and advantageous method to UV–Vis and MS/MS in bioavailability studies.

Atorvastatin: A Review of Analytical Methods for Pharmaceutical Quality Control and Monitoring

Background: Atorvastatin, a lipid-regulating drug, was the best-selling drug in the world in the early 2000s. Thus, monitoring of this drug is important because it is accessible to a large portion of the population. In addition, its quality control is fundamental to provide quality medicines. Method of analysis can be the first step in the rational use of pharmaceuticals. Objective/Methods: In this context, a critical review of analytical methods present in the literature and official compendia for the pharmaceutical quality control of atorvastatin was made. Results: Among the analytical methods most used in the evaluation of atorvastatin, HPLC is highlighted, followed by HPLC coupled to MS, and spectrophotometry in UV. Tablets are the most studied pharmaceutical samples, and plasma is the most studied biological matrix. In the literature, studies with atorvastatin-based pharmaceutical products are more common than biological materials. Acetonitrile is the organic solvent most commonly used in the methods surveyed to evaluate atorvastatin. Conclusions: Currently, awareness of the impact that the analytical choice has on the health of the operator and the environment is growing. Therefore, the suitability of existing methods for the determination of atorvastatin can be made to adhere to the current analytical chemistry. In this way, the analytical, environmental, and human consciousness will remain united. Highlights: Although the literature shows interesting methods from an economic and environmental point of view, such as UV, Vis miniaturized, and TLC, they can still be improved to meet the requirements of the current sustainable analytical chemistry.

Submission of Rifaximin to Different Techniques: Characterization, Solubility Study, and Microbiological Evaluation

Rifaximin, an oral antimicrobial drug, is marketed as 200-mg tablets. The daily dose ranges from 600 mg (1 tablet 3 times a day) to 800 mg (2 tablets twice a day). It is used for a wide range of ages, from adults to children, since it is indicated for the treatment of hepatic encephalopathy, travelers' diarrhea, irritable bowel syndrome, Clostridium difficile, ulcerative colitis, and acute diarrhea. The success of pharmacotherapy will depend on correct fulfillment of drug administration; however, it becomes difficult when the tablets are large and the doses are frequent. Rifaximin belongs to class IV according to the Biopharmaceutic Classification System (BCS), meaning that it is both poorly soluble and poorly permeable. Thus, in this study, solubility of rifaximin was improved by its complexation to β-cyclodextrin by (i) phase solubility diagram, (ii) malaxation, and (iii) decreasing particle size by wet milling. Improved solubility provides lower doses and facilitates compliance with pharmacotherapy. The products formed were analyzed by spectrophotometry in the infrared region (FT-IR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Also, their solubility and microbiological activity were determined. The products obtained in all techniques were more soluble than the free drug; they presented higher thermal stability and antimicrobial potency was approximately 100% with all the formulations. It is important to highlight that the treatment failure not only affects the quality of life of the patients, but also contributes significantly to the economic burden of the health system. Therefore, these findings are extremely interesting, both from a technological and financial point of view.

New and miniaturized method for analysis of enrofloxacin in palatable tablets

Enrofloxacin is an antimicrobial for oral use, from the fluoroquinolones of second-generation class, and it is the first fluoroquinolone used in veterinary for the treatment of bacterial infections. The development of trustworthy analytical methods has extreme importance for the assurance of safety, quality and therapeutic efficiency of pharmaceuticals. Previous articles in the literature describe several analytical methods for evaluation of enrofloxacin, but they do not use spectrophotometry in the visible region, nor use a miniaturized method or ecologically correct. In this work an analytical method for quantification of enrofloxacin in palatable tablets for veterinary prescriptions was developed and validated by spectrophotometry in the visible region. This method used a spectrophotometer UV-Vis BMG LabTechSpectrostar Nano, solution of iron chloride 0.5% as complexing agent, microplates and the analyses were conducted at 430 nm. The validation was conducted following international guides and showed linearity between the concentrations of 100 and 200 μg/ mL, selectivity, precision (intraday RSD 0.52%, interday RSD 0.44% and interanalyst RSD 0.56%), accuracy of 98.51% and robustness to time of analysis variation and wavelength. Therefore, the developed method approached the required parameters of validation and can be considered suitable for quantification of enrofloxacin in palatable tablets. The method also involves characteristics in green analytical chemistry for the current pharmaceutical analysis. This work contemplates a miniaturized, clean, innovator, fast and low cost method by spectrophotometry in the visible region for quantification of enrofloxacin in palatable tablets.

Quantitative analysis of cefazolin sodium in lyophilized powder by infrared spectrophotometry: Green, low cost, fast and effective

Cefazolin sodium is a broad-spectrum antibiotic used in the treatment of infectious diseases in humans and in the surgical prophylaxis. Thus, since a considerable number of people have access to this drug, it is of great interest of quality control. The aim of this study was development and validation of a green method by Fourier-Transform Infrared (FT-IR) transmission spectrophotometry for the quantification of cefazolin sodium in lyophilized powder. This technique is widely used in the pharmaceutical industry due to its ease of execution, low cost, safety and high precision and accuracy. It has been employed in the quality control routine of numerous pharmaceuticals in order to identify them and quantify their active principles. The proposed method was completely validated according ICH guidelines, showing selectivity, accuracy, precision, robustness and linearity. It was linear over the concentration range of 0.4-1.7 mg with correlation coefficient 0.999, limits of detection and quantification of 0.017 mg and 0.052 mg, respectively, precise, accurate and robust when changes in the time, pressure and mark of potassium bromide were carried out during the preparation of the pellets. The proposed method was successfully applied to the qualitative and quantitative quality control of cefazolin sodium in lyophilized powder. In addition, the method is considered green, clean and sustainable since it uses only a single reagent; it is a fast, low-cost and environmentally friendly method.

Evolution of green chemistry and its multidimensional impacts: A review

The growing process of industrialization was a milestone for world economic evolution. Since the 1940s, social movements have revolutionized green chemistry and provided shifts in industrial positions and sustainable processes with advances in environmental impact and awareness of companies and population. Paul Anastas and John Warner, in the 1990s, postulated the 12 principles of Green Chemistry, which are based on the minimization or non-use of toxic solvents in chemical processes and analyzes, as well as, the non-generation of residues from these processes. One of the most active areas of Research and Development in Green Chemistry is the development of analytical methodologies, giving rise to the so-called Green Analytical Chemistry. The impacts of green chemistry on pharmaceutical analyzes, environmental, population, analyst and company are described in this review and they are multidimensional. Every choice and analytical attitude has consequences both in the final product and in everything that surrounds it. The future of green chemistry as well as our future and the environment is also contemplated in this work.

Review for Analytical Methods for the Determination of Sodium Cephalothin

Infections are the second leading cause of global morbidity and mortality, therefore it is highly important to study the antimicrobial agents such as cephalosporins. Cephalothin, an antimicrobial agent that belongs to the class of cephalosporins, has bactericidal activity and it is widely used in the Brazilian health system. In literature, some analytical methods are found for the identification and quantification of this drug, which are essential for its quality control, which ensures maintaining the product characteristics, therapeutic efficacy and patient's safety. The aim of this article is to review the available information on analytical methods for cephalothin. Thus, this study presents a literature review on cephalothin and the analytical methods developed for the analysis of this drug in official and scientific papers. It is essential to note that most of the developed methods used toxic and hazardous solvents, which makes necessary industries and researchers choose to develop environmental-friendly techniques, which will contribute to the harmonization of science, human, and environmental health.

Development of differentiated pharmaceutical packaging for greater autonomy and quality of life for physically and visually impaired patients

20–45% of the world population present special needs, permanent or provisional. This index is higher than that presented by the WHO, which determines that 10% of a country's population has some kind of disabled, in times of peace. This work proposes, focused on Assistive Technology, to seek solutions to daily problems encountered during the distribution of toothpaste for the toothbrushing of persons with visual impairment or with reduced mobility, through the development of a device that assists in the autonomy and independence of the individual, allowing their well-being and social inclusion. For this, an innovative packaging for toothpaste with important characteristics for the support was proposed, such as the presence of a pump valve and an adapter that guides the user to locate the exit of a predefined quantity of the toothpaste, without the need to handle the bristles of the brush, avoiding contaminations. The developed packaging material allows the user independence in day-to-day activities, which strengthens their self-esteem and quality of life, leading, consequently, to family well-being.

A New Green Method for the Quantitative Analysis of Enrofloxacin by Fourier-Transform Infrared Spectroscopy

Background: A green analytical chemistry method was developed for quantification of enrofloxacin in tablets. The drug, a second-generation fluoroquinolone, was first introduced in veterinary medicine for the treatment of various bacterial species. Objective: This study proposed to develop, validate, and apply a reliable, low-cost, fast, and simple IR spectroscopy method for quantitative routine determination of enrofloxacin in tablets. Methods: The method was completely validated according to the International Conference on Harmonisation guidelines, showing accuracy, precision, selectivity, robustness, and linearity. Results: It was linear over the concentration range of 1.0-3.0 mg with correlation coefficients >0.9999 and LOD and LOQ of 0.12 and 0.36 mg, respectively. Conclusions: Now that this IR method has met performance qualifications, it can be adopted and applied for the analysis of enrofloxacin tablets for production process control. The validated method can also be utilized to quantify enrofloxacin in tablets and thus is an environmentally friendly alternative for the routine analysis of enrofloxacin in quality control. Highlights: A new green method for the quantitative analysis of enrofloxacin by Fourier-Transform Infrared spectroscopy was validated. It is a fast, clean and low-cost alternative for the evaluation of enrofloxacin tablets.

Flucloxacillin: A Review of Characteristics, Properties and Analytical Methods

Bacterial resistance is a growing and worrying factor. The high reproducibility of these resistant microorganisms tends to influence the development of new drugs and research related to product quality control. Among the existing antimicrobials, flucloxacillin (FLU) was designed for oral and injectable administration with bactericidal activity. FLU sodium is the form used in pharmaceutical formulations. It is an antimicrobial resistant against penicillinase, an enzyme responsible for cleaving the beta-lactam ring of penicilins, which leads to inactivity of the drug. Qualitative and quantitative analyzes are essential to ensure quality of pharmaceuticals and health of the population. It is important that quality control is effective and appropriate, only then we can win the battle against microbial resistance. In this work, we want to highlight tthe characteristics of FLU as an important antibiotic and methods for the determination of FLU in pharmaceutical products and biological matrices. Among the analytical methods described in the literature for the determination of FLU, high performance liquid chromatography (HPLC) stands out. Anyway, this method uses toxic solvents (e.g. acetonitrile) long columns, which provide long runs, as well as produces large amounts of waste. Currently, the priority changed to develop ecologically correct, conscious and sustainable methods. This new view on analytical methods should be applied to FLU analyzes and used to develop and improve existing methods.

Quality of Ceftriaxone Sodium in Lyophilized Powder for Injection Evaluated by Clean, Fast, and Efficient Spectrophotometric Method

Ceftriaxone sodium, an antimicrobial agent that plays an important role in clinical practice, is successfully used to treat infections caused by most Gram-positive and Gram-negative organisms. Since there are few rapid analytical methods for ceftriaxone analysis to use in the pharmaceutical routine, the aim of this research was to develop a new method able to quantify this cephalosporin. Therefore, a sensitive, rapid, simple UV spectrophotometric method for the determination and quantification of ceftriaxone sodium was proposed. The UV detector was set at 241 nm. Beer's law obeyed the concentration range of 10-20 µg mL-1. Statistical comparison of the results with a well-established reported method showed excellent agreement and proved that there is no significant difference in the accuracy and precision. Intra- and interday variability for the method were less than 2% relative standard deviation. The proposed method was applied to the determination of the examined drugs in pharmaceutical formulations and the results demonstrated that the method is equally accurate, precise, and reproducible as the official methods.

DEVELOPMENT AND VALIDATION OF AN ECOLOGICAL, NEW AND RAPID STABILITY-INDICATING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY FOR QUANTITATIVE DETERMINATION OF AZTREONAM IN LYOPHILIZED POWDER FOR INJECTION

Aztreonam is a monocyclic synthetic antimicrobial with bactericidal activity against Gram-negative bacteria, the first agent from the monobactam family to be therapeutically approved. It was developed and validated analytical method using high performance liquid chromatography with UV detection at 292 nm to quantify the aztreonam. Furthermore, assessing stability through stress tests was carried out. The chromatographic separation was carried out by reverse phase on an Agilent C18 column (250 x 4.6 mm, 5 µm) with a mobile phase composed of water:ethanol (70:30, v/v) adjusted to pH 2.5 with acetic acid, pumped isocratically at a flow rate of 0.5 mL/min. The validation parameters linearity, selectivity, precision, accuracy, robustness, limits of detection and quantification were determined. The method proposed provides linear response within the concentration range of 45-95 µg/mL for aztreonam. Results obtained were found to be satisfactory. The proposed method is linear, accurate, precise, selective, and robust being able to quantify the aztreonam in raw material and in pharmaceutical preparations. The validated method was suitable for applications in quality control laboratories.

Synthetic detergents: 100 years of history

In the year 2016 the synthetic detergents complete 100 years and in this story they evolved as cleaners. They are already part of the routine of thousands of people worldwide. For a higher power of cleaning of the detergent, today, are added phosphates, the main responsible for environmental problems. After 100 years of synthetic detergents, the effect of the combination of various cleaners on the environment is a gap. Legislation and guidelines about the other components of the formula of cleaners still missing. Even the term biodegradable can be best placed on the diversity of products currently entitled biodegradable. A lot attitudes can still be taken to continuously improve the relationship between the parties involved, animals, plants, waters and men, so that in another 100 years continues to exist this interaction with the environment without destroying it. The marketing used by synthetic detergent companies evolved a lot over the years and showed maturity to deal with changes in theories and strategies for promotion and even with the constant social reform that its consumer lived, accompanying them intelligently to be able to capture their changing needs and desires, and so assemble the best way to connect to them. This paper focuses on the subject synthetic detergents as well as (i) types and applications, (ii) threats, (iii) sustainability, (iv) legislation, (v) packaging and (vi) marketing strategies.

Quantification of Rifaximin in Tablets by Spectrophotometric Method Ecofriendly in Ultraviolet Region

Rifaximin is an oral nonabsorbable antibiotic that acts locally in the gastrointestinal tract with minimal systemic adverse effects. It does not have spectrophotometric method ecofriendly in the ultraviolet region described in official compendiums and literature. The analytical techniques for determination of rifaximin reported in the literature require large amount of time to release results and are significantly onerous. Furthermore, they use toxic reagents both for the operator and environment and, therefore, cannot be considered environmentally friendly analytical techniques. The objective of this study was to develop and validate an ecofriendly spectrophotometric method in the ultraviolet region to quantify rifaximin in tablets. The method was validated, showing linearity, selectivity, precision, accuracy, and robustness. It was linear over the concentration range of 10-30 mg L(-1) with correlation coefficients greater than 0.9999 and limits of detection and quantification of 1.39 and 4.22 mg L(-1), respectively. The validated method is useful and applied for the routine quality control of rifaximin, since it is simple with inexpensive conditions and fast in the release of results, optimizes analysts and equipment, and uses environmentally friendly solvents, being considered a green method, which does not prejudice either the operator or the environment.

Recent Advances in the Study of the Inclusion Complex Darunavir-β-Cyclodextrin by LC-MS

Darunavir is a protease inhibitor used in the treatment of human immunodeficiency virus (HIV) infection. This work proposes a LC-MS method indicative of stability for the determination of darunavir in the complex darunavir-β-cyclodextrin, a recent advance for the use of antiretroviral. The method was completely validated according to the International Conference on Harmonization guidelines, showing accuracy, precision, selectivity, robustness, and linearity. The separation was achieved on a 250 mm × 4.6 mm CN Luna column with water +0.1% glacial acetic acid-acetonitrile +0.1% glacial acetic acid, 60 + 40 (v/v) at phase at a flow rate of 1.0 mL/min. UV detection was performed at 268 nm at 25°C. Mass spectral analyses were performed with electrospray ionization ion source and ion trap mass analyzer. The method was linear over the concentration range of 10-60 μg/mL with correlation coefficients at 1.000 and LODs and LOQ of 1.13 and 3.43 μg/mL, respectively. The drug for HIV infection was subjected to acid, basic, oxidative, and neutral degradation and photolysis. Degradation products were identified by LC-MS and LC-tandem MS; therefore, the method can be regarded as indicative of stability. The validated method is very useful to the routine quality control for quantification of darunavir in inclusion complex darunavir-β-cyclodextrin.

Increasing doxycycline hyclate photostability by complexation with β-cyclodextrin

Doxycycline hyclate (DOX) is a highly photosensitive drug, a feature that limits the stability of the corresponding dosage forms. The main objectives of this work were the preparation and characterization of an inclusion complex of DOX with β-cyclodextrin (βCD) and to investigate if this approach could improve the photostability of the drug. Guest-host interactions were investigated using nuclear magnetic resonance, which were afterwards combined with molecular modeling methods to study the complex formation and its three-dimensional structure was proposed. A freeze-drying method was applied to obtain the complex in the solid state, which was further confirmed by thermal and spectroscopic techniques. To evaluate the complexation effect on DOX integrity, the photostability of the inclusion complex was studied, with a significant decrease in the photodegradation of DOX being found in aqueous solution upon complexation. Finally, the photoprotection produced by the complexation was evaluated by means of an antimicrobial assay. Overall, the presented results suggest that the formulation of DOX complexed with βCD constitutes an interesting approach for the preparation of pharmaceutical dosage forms of DOX with enhanced stability properties.