Formulation, gastrointestinal transit studies and absorption of amphotericin B-containing solid lipid nanoparticles in rats

Successful delivery of pharmaceuticals orally requires a firm understanding of how dosage forms behave during their passage through the gastrointestinal (GI) tract. In this study, the GI transit time and absorption of amphotericin B (AmB) solid lipid nanoparticles (SLN) were investigated in rats, using paracetamol (PAR) and sulphapyridine (SP) as indirect markers. A high encapsulation efficiency of 91.2% was obtained for the AmB SLNs. The SLNs were exhaustively characterised with regards to size, zeta potential (ZP), viscosity, density, migration propensity within agarose gel, in vitro drug release and morphology, to ensure similar disposition in the GI tract after simultaneous oral administration. Freeze-drying did not significantly alter the size or ZP of the AmB SLNs, and in vitro drug release from fresh and freeze-dried SLNs were identical. AmB, PAR and sulphasalazine (SSZ) (the latter being the prodrug of SP) were individually formulated into SLNs using beeswax and theobroma oil as the lipid matrix. The z-averages, polydispersity indices and ZPs of the SLNs ranged from 206.5-224.8 nm, 0.161-0.218 and |61.90|-|71.90| mV, respectively. Gel electrophoresis studies indicated a similar movement propensity among the three SLNs as their migration distances were identical (22.2-22.4 mm) within agarose gel. Scanning electron and atomic force microscopy studies revealed that all three SLNs were spherical in morphology and with similar surface characteristics. The SLNs were assessed for changes in size and surface charge on exposure to simulated GI fluids using dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA). On contact with the fluids, the particles had a slight increase in size due to ingress of the dissolution media. NTA results were found to be more beneficial than DLS as the latter was biased towards larger particles that were present possibly due to aggregation. After incubation in simulated gastric fluid followed by simulated intestinal fluid (mimicking gastric emptying), all the SLNs were found to be less than 350 nm in size and neutral in charge, which are optimal attributes for intestinal absorption. Time-of-flight secondary ion mass spectroscopic (ToF-SIMS) analyses revealed minimal drug amounts on the surfaces of the particles indicating that drug location was in the core of the SLNs. A developed and validated high-performance liquid chromatography (HPLC) method for simultaneous assay of the drugs in rat plasma using piroxicam as internal standard was found to be sensitive, accurate and precise, with drug recovery from plasma exceeding 92% in each case. A pilot GI transit study conducted in rats showed that the HPLC method was appropriate for the study. In the main study, the effects of food on the transit and absorption of the AmB SLNs were investigated. The presence of food slowed the transit of the SLNs in the GI tract. The gastric transit time of the AmB SLNs was estimated indirectly using PAR and was obtained as 1.71-2.25 hr. Caecal arrival time (CAT) of the AmB SLNs was estimated using SP detection in plasma as SSZ metabolism to produce SP occurs predominantly by the activity of colonic flora. In both fasted and fed states, CAT was 1.80-1.90 hr whereas transit time through the small intestine was 1.65-1.79 hr. A delayed rate of AmB absorption was observed in the fed state however, the extent of absorption was not affected by food. The percentage AmB absorption during the fasted state in the stomach, small intestine and colon were not significantly different from absorption within the respective regions in the fed state. In both states however, absorption was highest in the colon and appeared to be a summation of small intestinal absorption plus absorption proper within the colon. The study indicated that, AmB SLNs irrespective of food status were slowly but predominantly taken up via the lymphatic route and the small intestine was the most favourable site for their absorption. The data obtained indicate that it is possible to enhance the bioavailability of AmB through its incorporation into SLNs. Further enhancement of AmB bioavailability can be achieved through appropriate formulation interventions aimed at slowing transit of the SLNs in the small intestine. Finally, being a lipid-based system, the SLNs may have a potential to reduce the nephrotoxic effects of AmB

Formulation, gastrointestinal transit studies and absorption of amphotericin B-containing solid lipid nanoparticles in rats

Successful delivery of pharmaceuticals orally requires a firm understanding of how dosage forms behave during their passage through the gastrointestinal (GI) tract. In this study, the GI transit time and absorption of amphotericin B (AmB) solid lipid nanoparticles (SLN) were investigated in rats, using paracetamol (PAR) and sulphapyridine (SP) as indirect markers. A high encapsulation efficiency of 91.2% was obtained for the AmB SLNs. The SLNs were exhaustively characterised with regards to size, zeta potential (ZP), viscosity, density, migration propensity within agarose gel, in vitro drug release and morphology, to ensure similar disposition in the GI tract after simultaneous oral administration. Freeze-drying did not significantly alter the size or ZP of the AmB SLNs, and in vitro drug release from fresh and freeze-dried SLNs were identical. AmB, PAR and sulphasalazine (SSZ) (the latter being the prodrug of SP) were individually formulated into SLNs using beeswax and theobroma oil as the lipid matrix. The z-averages, polydispersity indices and ZPs of the SLNs ranged from 206.5-224.8 nm, 0.161-0.218 and |61.90|-|71.90| mV, respectively. Gel electrophoresis studies indicated a similar movement propensity among the three SLNs as their migration distances were identical (22.2-22.4 mm) within agarose gel. Scanning electron and atomic force microscopy studies revealed that all three SLNs were spherical in morphology and with similar surface characteristics. The SLNs were assessed for changes in size and surface charge on exposure to simulated GI fluids using dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA). On contact with the fluids, the particles had a slight increase in size due to ingress of the dissolution media. NTA results were found to be more beneficial than DLS as the latter was biased towards larger particles that were present possibly due to aggregation. After incubation in simulated gastric fluid followed by simulated intestinal fluid (mimicking gastric emptying), all the SLNs were found to be less than 350 nm in size and neutral in charge, which are optimal attributes for intestinal absorption. Time-of-flight secondary ion mass spectroscopic (ToF-SIMS) analyses revealed minimal drug amounts on the surfaces of the particles indicating that drug location was in the core of the SLNs. A developed and validated high-performance liquid chromatography (HPLC) method for simultaneous assay of the drugs in rat plasma using piroxicam as internal standard was found to be sensitive, accurate and precise, with drug recovery from plasma exceeding 92% in each case. A pilot GI transit study conducted in rats showed that the HPLC method was appropriate for the study. In the main study, the effects of food on the transit and absorption of the AmB SLNs were investigated. The presence of food slowed the transit of the SLNs in the GI tract. The gastric transit time of the AmB SLNs was estimated indirectly using PAR and was obtained as 1.71-2.25 hr. Caecal arrival time (CAT) of the AmB SLNs was estimated using SP detection in plasma as SSZ metabolism to produce SP occurs predominantly by the activity of colonic flora. In both fasted and fed states, CAT was 1.80-1.90 hr whereas transit time through the small intestine was 1.65-1.79 hr. A delayed rate of AmB absorption was observed in the fed state however, the extent of absorption was not affected by food. The percentage AmB absorption during the fasted state in the stomach, small intestine and colon were not significantly different from absorption within the respective regions in the fed state. In both states however, absorption was highest in the colon and appeared to be a summation of small intestinal absorption plus absorption proper within the colon. The study indicated that, AmB SLNs irrespective of food status were slowly but predominantly taken up via the lymphatic route and the small intestine was the most favourable site for their absorption. The data obtained indicate that it is possible to enhance the bioavailability of AmB through its incorporation into SLNs. Further enhancement of AmB bioavailability can be achieved through appropriate formulation interventions aimed at slowing transit of the SLNs in the small intestine. Finally, being a lipid-based system, the SLNs may have a potential to reduce the nephrotoxic effects of AmB

Lyophilized drug-loaded solid lipid nanoparticles formulated with beeswax and theobroma oil

Solid lipid nanoparticles (SLNs) have the potential to enhance the systemic availability of an active pharmaceutical ingredient (API) or reduce its toxicity through uptake of the SLNs from the gastrointestinal tract or controlled release of the API, respectively. In both aspects, the responses of the lipid matrix to external challenges is crucial. Here, we evaluate the effects of lyophilization on key responses of 1:1 beeswax–theobroma oil matrix SLNs using three model drugs: Amphotericin B (AMB), paracetamol (PAR), and sulfasalazine (SSZ). Fresh SLNs were stable with sizes ranging between 206.5–236.9 nm. Lyophilization and storage for 24 months (4–8 °C) caused a 1.6- and 1.5-fold increase in size, respectively, in all three SLNs. Zeta potential was >60 mV in fresh, stored, and lyophilized SLNs, indicating good colloidal stability. Drug release was not significantly affected by lyophilization up to 8 h. Drug release percentages at end time were 11.8 ± 0.4, 65.9 ± 0.04, and 31.4 ± 1.95% from fresh AMB-SLNs, PAR-SLNs, and SSZ-SLNs, respectively, and 11.4 ± 0.4, 76.04 ± 0.21, and 31.6 ± 0.33% from lyophilized SLNs, respectively. Thus, rate of release is dependent on API solubility (AMB < SSZ < PAR). Drug release from each matrix followed the Higuchi model and was not affected by lyophilization. The above SLNs show potential for use in delivering hydrophilic and lipophilic drugs

Practicality of 3D Printed Personalized Medicines in Therapeutics

Technological advances in science over the past century have paved the way for remedial treatment outcomes in various diseases. Pharmacogenomic predispositions, the emergence of multidrug resistance, medication and formulation errors contribute significantly to patient mortality. The concept of "personalized" or "precision" medicines provides a window to addressing these issues and hence reducing mortality. The emergence of three-dimensional printing of medicines over the past decades has generated interests in therapeutics and dispensing, whereby the provisions of personalized medicines can be built within the framework of producing medicines at dispensaries or pharmacies. This plan is a good replacement of the fit-for-all modality in conventional therapeutics, where clinicians are constrained to prescribe pre-formulated dose units available on the market. However, three-dimension printing of personalized medicines faces several hurdles, but these are not insurmountable. In this review, we explore the relevance of personalized medicines in therapeutics and how three-dimensional printing makes a good fit in current gaps within conventional therapeutics in order to secure an effective implementation of personalized medicines. We also explore the deployment of three-dimensional printing of personalized medicines based on practical, legal and regulatory provisions. Copyright 2021 Amekyeh, Tarlochan and Billa.Scopu

Correlating gastric emptying of amphotericin B and paracetamol solid lipid nanoparticles with changes in particle surface chemistry

Oral delivery of pharmaceuticals requires that they retain their physical and chemical attributes during transit within the gastrointestinal (GI) tract, for the manifestation of desired therapeutic profiles. Solid lipid nanoparticles (SLNs) are used as carriers to improve the absorption of hydrophobic drugs. In this study, we examine the stability of amphotericin B (AmB) and paracetamol (PAR) SLNs in simulated GI fluids during gastric emptying. On contact with the simulated fluids, the particles increased in size due to ingress of the dissolution media into the particles. Simulated gastric emptying revealed that the formulations had mean sizes <350 nm and neutral surface charges, both of which are optimal for intestinal absorption of SLNs. There was ingress of the fluids into the SLNs, followed by diffusion of the dissolved drug, whose rate depended on the solubility of the loaded-drug in the particular medium. Time-of-flight secondary ion mass spectrometry analyses indicated that drug loading followed the core-shell model and that the AmB SLNs have a more drug-enriched core than the PAR SLNs do. The AmB SLNs are therefore a very suitable carrier of AmB for oral delivery. The stability of the SLNs in the simulated GI media indicates their suitability for oral delivery

Lyophilized Drug-Loaded Solid Lipid Nanoparticles Formulated with Beeswax and Theobroma Oil

Solid lipid nanoparticles (SLNs) have the potential to enhance the systemic availability of an active pharmaceutical ingredient (API) or reduce its toxicity through uptake of the SLNs from the gastrointestinal tract or controlled release of the API, respectively. In both aspects, the responses of the lipid matrix to external challenges is crucial. Here, we evaluate the effects of lyophilization on key responses of 1:1 beeswax–theobroma oil matrix SLNs using three model drugs: amphotericin B (AMB), paracetamol (PAR), and sulfasalazine (SSZ). Fresh SLNs were stable with sizes ranging between 206.5–236.9 nm. Lyophilization and storage for 24 months (4–8 °C) caused a 1.6- and 1.5-fold increase in size, respectively, in all three SLNs. Zeta potential was &gt;60 mV in fresh, stored, and lyophilized SLNs, indicating good colloidal stability. Drug release was not significantly affected by lyophilization up to 8 h. Drug release percentages at end time were 11.8 ± 0.4, 65.9 ± 0.04, and 31.4 ± 1.95% from fresh AMB-SLNs, PAR-SLNs, and SSZ-SLNs, respectively, and 11.4 ± 0.4, 76.04 ± 0.21, and 31.6 ± 0.33% from lyophilized SLNs, respectively. Thus, rate of release is dependent on API solubility (AMB &lt; SSZ &lt; PAR). Drug release from each matrix followed the Higuchi model and was not affected by lyophilization. The above SLNs show potential for use in delivering hydrophilic and lipophilic drugs

Prospects of Curcumin Nanoformulations in Cancer Management

There is increasing interest in the use of natural compounds with beneficial pharmacological effects for managing diseases. Curcumin (CUR) is a phytochemical that is reportedly effective against some cancers through its ability to regulate signaling pathways and protein expression in cancer development and progression. Unfortunately, its use is limited due to its hydrophobicity, low bioavailability, chemical instability, photodegradation, and fast metabolism. Nanoparticles (NPs) are drug delivery systems that can increase the bioavailability of hydrophobic drugs and improve drug targeting to cancer cells via different mechanisms and formulation techniques. In this review, we have discussed various CUR-NPs that have been evaluated for their potential use in treating cancers. Formulations reviewed include lipid, gold, zinc oxide, magnetic, polymeric, and silica NPs, as well as micelles, dendrimers, nanogels, cyclodextrin complexes, and liposomes, with an emphasis on their formulation and characteristics. CUR incorporation into the NPs enhanced its pharmaceutical and therapeutic significance with respect to solubility, absorption, bioavailability, stability, plasma half-life, targeted delivery, and anticancer effect. Our review shows that several CUR-NPs have promising anticancer activity; however, clinical reports on them are limited. We believe that clinical trials must be conducted on CUR-NPs to ensure their effective translation into clinical applications

Prospects of Curcumin Nanoformulations in Cancer Management

There is increasing interest in the use of natural compounds with beneficial pharmacological effects for managing diseases. Curcumin (CUR) is a phytochemical that is reportedly effective against some cancers through its ability to regulate signaling pathways and protein expression in cancer development and progression. Unfortunately, its use is limited due to its hydrophobicity, low bioavailability, chemical instability, photodegradation, and fast metabolism. Nanoparticles (NPs) are drug delivery systems that can increase the bioavailability of hydrophobic drugs and improve drug targeting to cancer cells via different mechanisms and formulation techniques. In this review, we have discussed various CUR-NPs that have been evaluated for their potential use in treating cancers. Formulations reviewed include lipid, gold, zinc oxide, magnetic, polymeric, and silica NPs, as well as micelles, dendrimers, nanogels, cyclodextrin complexes, and liposomes, with an emphasis on their formulation and characteristics. CUR incorporation into the NPs enhanced its pharmaceutical and therapeutic significance with respect to solubility, absorption, bioavailability, stability, plasma half-life, targeted delivery, and anticancer effect. Our review shows that several CUR-NPs have promising anticancer activity; however, clinical reports on them are limited. We believe that clinical trials must be conducted on CUR-NPs to ensure their effective translation into clinical applications

Evaluation of packaging, labels, and some physicochemical properties of herbal antimalarial products on the Ghanaian market

Introduction: Malaria is a parasitic disease that is endemic in tropical areas and can be life-threatening. There has been a decrease in the prevalence of malaria in Ghana but the burden of the disease is still high in the country. Many Ghanaians depend on herbal products for malaria treatment. This study aimed to survey and evaluate commercial herbal antimalarials in the Volta Region of Ghana. Methods: A survey of finished herbal antimalarials was done at herbal shops, pharmacies, and over-the-counter medicine seller shops. Products available on shelves were purchased and their details were recorded, after which they were examined using a visual inspection tool. The density, pH, and extract weight per dose of each sample were also determined. Results: Thirty-four liquid formulations (A-1–34) containing 1–9 different herbs were found. The majority of the product labels had errors in consumer age classifications. Unconventional ways of stating doses were found on two products (A-13, “tot”; A-19, cupful). Six products did not have dosing devices. No duration of treatment was indicated on 24 products. Dose errors were found on A-14 and A-22. Samples A-17 and A-28 did not have registration or batch numbers. Product A-28 did not have its herbs listed on it and was indicated for persons aged 3–8 years at a dose of 45 mL. The relative density range for the products was 0.997–1.015. From the pH investigation, no product was extremely erosive; however, 10 samples were deemed erosive (pH, 3.0–3.99), whereas 24 were minimally erosive (pH, ≥4.0). The extract weight per dose volume (20–90 mL) was 0.048–1.766 g, indicating that unit dose capsules or tablets could be formulated from the products. Conclusion: The findings clearly show that Ghanaian authorities responsible for regulating herbal products must enforce guidelines for the formulation, label details, and sale of antimalarial products. Additionally, the unpleasant taste of liquid herbal mixtures can affect patient compliance and dosing convenience; therefore, it is recommended that oral solid dosage forms of herbal antimalarials are produced as alternatives to the liquid mixtures

Correlates of patient satisfaction with pain management at the Ho Teaching Hospital in Ghana: A cross-sectional study

Pain is a symptom that many people who visit the hospital with various illnesses experience. Inadequate pain management has been regularly shown to have a negative impact on patients' health and reduce patient satisfaction. Patients' satisfaction with pain management is therefore important. The aim of this study was therefore to assess patients’ satisfaction and experience with pain management at the Ho Teaching Hospital, Volta Region, Ghana. The study was a prospective cross-sectional investigation and was carried out among 196 adult patients (older than 18 years) at the emergency, medical, and surgical wards. Data was collected using the 2010 version of the patient outcome and satisfaction survey questionnaire developed by the American Pain Society. Descriptive and inferential statistical analysis were employed in analysing the data obtained from the respondents. p-value less than 0.05 was considered as statistically significant.The results revealed that 96% of the respondents were satisfied with their pain management. Expectations for pain treatment (r = 0.221, p-value=0.002), percentage of pain relief in first 48 h (r = 0.439, p-value<0.001) and how helpful the information was (r = 0.158, p-value=0.027) were positively correlated with satisfaction with pain treatment. In addition, the median satisfaction with pain treatment was higher for those with knowledge on pain medication (p-value=0.043), and patients who were allowed to participate in decision-making indicated a higher level of satisfaction.The majority of patients (95% with acute pain and 100% with chronic pain) were satisfied with their pain management. Aside the effective use of analgesics, it was found that patient satisfaction can also be enhanced by good patient-provider relationships, providing patients with helpful information about their pain treatment, and allowing patients to participate in decisions about their pain management. This research is the first to provide such information for pain management in the Volta Region of Ghana