In-use Test Research Articles

Pilot Clinical Safety and Efficacy Evaluation of a Topical 3% Tranexamic Acid Cream and Serum Protocol for Managing Facial Hyperpigmentation in Caucasian Patients

Facial hyperpigmentation is a highly prevalent dermatological condition, characterized by dark spots on the skin resulting from excess melanin production. Hyperpigmentation significantly impacts patients’ quality of life and self-esteem. Current treatments often present disadvantages linked to poor product tolerability. A topical cosmetic approach combining three lightening active ingredients (tranexamic acid, niacinamide, vitamin C) offers a new option for treating dark spots on the skin. The present in-use test under dermatological control evaluated the clinical safety and efficacy of a cream and serum containing these three ingredients, formulated with hyaluronic acid for enhanced delivery, stability, and efficacy. A total of 22 Caucasian patients with facial hyperpigmentation, both male and female, aged between 45 and 67 years, applied the cream and serum for 8 weeks. Clinical assessments, colorimetric evaluations, standardized photography, and self-assessment questionnaires were used to measure outcomes. No serious adverse effects were recorded, and the incidence of local adverse effects was low, highlighting good tolerability of the investigated test items. In most participants, significant improvements in hyperpigmented areas were recorded. Clinical scoring by the dermatologist investigator indicated a statistically significant 13% reduction in color intensity and a 6% reduction in the size of dark spots after 8 weeks of treatment. Colorimetric evaluation showed a statistically significant 1% increase in luminosity (L* parameter) and an 8% improvement in the Individual Typological Angle (ITA°) in endpoint, indicating lighter skin spots. Subjective assessments reflected high user satisfaction, with 95% of participants noting improvements in skin hydration and luminosity, and 77% reporting a reduced appearance of dark spots. Overall, the present work supports the use of tranexamic acid, niacinamide, and vitamin C as an effective and well-tolerated combined topical management option for hyperpigmentation. This combination offers a viable alternative to classical whiteners for individuals seeking to reduce facial skin coloration imbalance and improve skin tone.

Determination of in-use properties of paper towels

For a hygiene paper such as tissue and towel, strength, softness, and absorbency are known as attributes that a user is looking for. It is proposed here that purchasing decisions are likely to be influenced by in-use experiences, which may be quite different from the physical properties measured with current standardized tests. There have been continuous efforts on developing physical test methods to replace subjective in-use tests because the benefits of the former are too significant to be overlooked. This paper considered some in-use test methods for paper towel products that can be carried out by panel members quickly in the course of sensory panel testing. In addition, laboratory tests were developed in an attempt to quantify such input. The sensory panel testing showed that (wet) strength and absorbency were the key contributions to the performance of paper towels. Softness did not show any significant contribution to it. Wet strength showed a high correlation with absorbency. The (wet) ball burst strength had the highest correlation with the in-use strength. Although both the tensile strength and the ball burst strength had a high correlation with preference, the ball burst tester is preferred because more reproducible and simpler to operate.

Mitigation of retinol-induced skin irritation by physiologic lipids: Evidence from patch testing.

There is a dearth of effective treatments to counter retinol-induced skin irritation. This study aimed to investigate the efficacy of three potential mitigants: (i) phytosteryl/octyldodecyl lauroyl glutamate (PLG), (ii) a physiologic lipid mixture (PLM) comprised of ceramide three and cholesterol, and (iii) niacinamide, in ameliorating irritation instigated by retinol. An occlusive human patch test, spanning 5 days, was undertaken on 18 Chinese participants aged between 23 and 40. It was designed as a randomized, double-blind, and vehicle-controlled study. Clinician erythema assessment (CEA) and instrumental evaluations were employed pre and post-test. Subsequently, a 4-week consumer in-use test, randomized and double-blind in nature, was executed to substantiate the soothing effects of PLG. Data from CEA and bioengineering assessments revealed that, in comparison to the vehicle control, both 2% PLG and 5% PLM notably curbed retinol-induced skin erythema and inflammation. Notably, PLG outperformed PLM. Conversely, 3% niacinamide did not offer relief against retinol-induced discomfort. The subsequent consumer in-use test affirmed that treatments with 2% PLG were better tolerated than those with the vehicle alone. To the best of our knowledge, this study represents the first confirmation that physiologic lipids effectively mitigate retinol-induced irritation. Given their capacity to counter retinol-induced irritation, physiologic lipids, particularly PLG, are recommended for incorporation in retinol regimens. Additionally, the Visia-CR a* value can serve as a robust objective measure for interpreting patch test outcomes.

305 New shampoo targeting dry dandruff: Evaluation program and results

Introduction: Dry dandruff (DD) is in the form of small, whitish flakes, not adherent to the scalp. Shampoo was developed for DD and formulated according to the requirements of 'conscious care' with 85% natural ingredients. Objective: Clinical studies were designed to assess its tolerance, efficacy and sensoriality with clinical, auto-assessment scoring, instrumental, pharmaco clinical methods and an in-use test. Material and methods: The in vivo studies were carried out on a total panel of 121 subjects corresponding to the target of the product. First, in use tolerance under dermatological control was investigated for 3 weeks (W). Efficacy and persistence were evaluated for 8 W to follow anti-dandruff-efficacy, scalp itching and discomfort and to measure hydration (HI), Trans Epidermal Water loss (TEWL) and pH of the scalp. Scalp microflora was analysed by NGS sequencing from swabs sampled after 2 and 4 W. The respect of skin barrier was evaluated on skin explants. Consumer use test of 3W was carried out to assess cosmetic acceptability and efficacy. Results: The results showed a very good tolerance and a decrease of dandruff, itching and discomfort scores. HI increased at W2. PH and TEWL did not change significantly. Regarding scalp microbiome, an increase of mycobiota diversity and significant change from W2 of bacteria population were observed. The respect for the integrity of the skin barrier was also shown. Cosmetic qualities and efficacy were appreciated. Conclusion: The new anti-dandruff shampoo displays a very good tolerance, anti-dandruff and soothing effects that are persistent while respecting skin barrier and a very good acceptability and efficay. The scalp microbiota is rebalanced, reflecting a strong relation between skin disorders and flora. All this evidence provides the consumer with a quality product that is well tolerated, effective and in line with expectations of naturality.

289 High-level stabilized retinol serum balances bioactivity and dermal tolerance

Retinol, an established topical ingredient for improving signs of photo-aging, is often limited in concentration due to the potential for low-level visible and sensory signs of irritation. A new anhydrous, 0.5% stabilized retinol serum was developed, balancing bioactivity and tolerability. This patented formula uses the Relative Polarity Index (RPI) between skin, retinol, and emollient ratios, allowing for controlled bio-delivery of retinol to skin. The product also includes skin-smoothing emollients, and antioxidants to stabilize the retinol. Retinol bioactivity and tolerability were first evaluated through gene and protein expression using human skin explants. Gene expression results indicated significant induction of genes with anti-aging benefits, such as cellular retinoic-acid binding protein-2 (CRABP2), a highly sensitive marker of retinoid bioactivity, Heparin-binding EGF-like growth factor (HBEGF), and hyaluronan synthase-3 (HAS3). Additionally, minimal to non-significant induction of IL-8, an inflammatory irritation marker, was observed compared to untreated controls. Histology results also demonstrated significantly increased collagen production. To further evaluate irritation potential, a clinical modified cumulative patch model was developed to differentiate irritation of retinol products. The new 0.5% retinol serum was found to have significantly less irritation (p<0.05) versus a competitive in-market 0.5% retinol formulation. A 4-week clinical in-use test was performed to assess the facial tolerance and self-perceived efficacy of the serum. Study results concluded daily use was well-tolerated, with no statistically significant increases (p<0.05) in tolerance parameters. Moreover, self-perception questions yielded positive results for improvements on visible aging attributes, confirming our ex vivo results. This new 0.5% retinol serum delivers bioactive retinol to target advanced visible signs of aging, without the increased irritation.

English

Nosocomial infections are enhanced due to a flop in the infection control processes such as disinfection. The aim of this study was to assess long term effectiveness and the stability of disinfectants currently used within healthcare settings in Accra, Ghana against two indicator pathogens. Two locally produced and two imported disinfectants usually used in health care settings were obtained. The efficacy and long-term stability of the disinfectants was done using the in-use method, with identified microbial culture isolates of Pseudomonas aeruginosa and Staphylococcus aureus. Counts of both test organisms (Pseudomonas aeruginosa and Staphylococcus aureus) were over and above the 5 &ge; CFU recommended standard. All the disinfectants failed the test. However, contamination was observed to be higher in local disinfectants as compared to those imported. Furthermore, Enterobacter spp was isolated as contaminant from one imported disinfected and Proteus spp was also isolated from one local disinfectant. Interestingly, one of the imported disinfectants (Disinfectant I) showed more stability and was effective in the long term. All disinfectants did not pass the in-use test. However, disinfectants that are produced locally are more unstable and ineffective. &nbsp; Key words: Infections, disinfectants, drug stability, hospital, pathogens, contamination.

In-use microbiological assessment of caffeine citrate 10 mg/mL oral solution

ObjectivesThis study was conducted to investigate the microbial contamination of caffeine citrate 10 mg/mL oral solution (CCOS) during a simulated in-use test in a clinical environment.MethodsA real-time in-use simulation study...

Design and stability study of an oral solution of amlodipine besylate for pediatric patients

IntroductionAmlodipine is an antihypertensive agent recommended for the management of hypertension in children and adolescents. The commercially available tablets of 5 and 10mg do not provide the necessary flexibility in dosing needed for treating children. Our goal was to develop a pediatric oral solution of amlodipine, using a robust manufacturing process suitable for ex-tempora and larger scale production. MethodsThe parameters API and preservative content, related substances, appearance and pH were studied under four different storage conditions. Samples were analyzed up to 12months. Microbiological quality was studied in an 18-week in-use test based on a two-times daily dosing schedule. ResultsThe stability of the formulation was influenced by storage conditions and composition. A formulation containing amlodipine besylate, sucrose syrup and methyl paraben remained physically stable for 12months at 4°C with no loss of amlodipine content. Related substances increased during the study but remained below 0.5%. In-use stability was proven up to 18weeks. DiscussionStorage under refrigerated conditions was necessary to prevent precipitation and to obtain an acceptable shelf-life. In conclusion, we have developed and validated an amlodipine oral solution, suitable for the pediatric population. This liquid formulation is preferred over manipulated commercial dosage forms or non-standardized extemporaneously compounded formulations.

Developing ways to evaluate in the laboratory how inhalation devices will be used by patients and care-givers: the need for clinically appropriate testing.

The design of methods in the pharmaceutical compendia for the laboratory-based evaluation of orally inhaled product (OIP) performance is intentionally aimed for simplicity and robustness in order to achieve the high degree of accuracy and precision required for the assurance of product quality in a regulated environment. Consequently, performance of the inhaler when used or even misused by the patient or care-giver has often not been assessed. Indeed, patient-use-based methodology has been developed in a somewhat piecemeal basis when a need has been perceived by the developing organization. There is, therefore, a lack of in-use test standardization across OIP platforms, and often important details have remained undisclosed beyond the sponsoring organization. The advent of international standards, such as ISO 20072:2009, that focus specifically on the OIP development process, together with the need to make these drug delivery devices more patient-friendly as an aid to improving compliance, is necessitating that clinically appropriate test procedures be standardized at the OIP class level. It is also important that their capabilities and limitations are well understood by stakeholders involved in the process. This article outlines how this process might take place, drawing on current examples in which significant advances in methodology have been achieved. Ideally, it is hoped that such procedures, once appropriately validated, might eventually become incorporated into the pharmacopeial literature as a resource for future inhaler developers, regulatory agencies, and clinicians seeking to understand how these devices will perform in use to augment ongoing product quality testing which is adequately served by existing methods.

Role of Hand Washing Antiseptics in Open Containers as Source of Pathogens in Nosocomial Infections

Contaminated hand washing antiseptics act as source of multi-drug and disinfectant resistant isolates in nosocomial infections through hands of Health care workers(HCW). Limited data available necessitated the present study. To determine rate of contaminated hand-washing antiseptic solutions in open containers(cHWAOC) by In-use test. To analyze role of cHWAOC in nosocomial infections as source of pathogens.Cross sectional prospective observational study of two months was conducted. 46 of 65 HWAOC from wards, OPDs,Casualty and ICUs were studied for microbial contamination by In-use test. Isolation, identification, antimicrobial susceptibility testing and antibiogram typing of isolates was done by standard laboratory procedures. Questionnaire surveywas used to asses hand washing practices in HWAOC. Correlation of isolates from cHWAOC with nosocomial infections was done by antibiogram typing and temporospatial association. Rate of c HWAOC was 2 8.26% ( 13/46). Distribution of cHWAOC was 21.8%, 50%, 66.67% and 15.38% respectively in wards, ICUs, Casualty and OPDs(P >0.05 NS). With an overall association in 11 nosocomial infections. Pseudomonas aeruginosa(5 antibiogram types) was predominant isolate(29.41%), followed by A. baumannii[3 types ] (17.64%) with association in 5 and 4 nosocomial infections respectively. Questionnaire survey revealed use of savlon in 80.43% of HWAOC with variable concentrations(2.5% to 17%v/v). Changing antiseptics in HWAOC was highly variable. Majority of the containers were washed by soap and water(73.9%). Higher rate of cHWAOC with Pseudomonas aeruginosa and Acinetobacter baumannii as most common isolates was observed. Possible role of cHWAOC as source of nosocomial pathogens could not be ruled out by antibiogram typing of isolates. Use of HWAOC in health care settings should be banned.

Comparison of contamination rates between preserved and preservative-free fluoroquinolone eyedrops

To evaluate the antimicrobial effectiveness of preservative-free fluoroquinolone products compared with benzalkonium chloride containing fluoroquinolones using the challenge test provided by the United States Pharmacopeia (USP) and the in-use test. 1. Challenge test: to compare the growth of microorganisms between different fluoroquinolone preparations, four test organisms, including Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger were chosen among five microorganisms listed by USP 2004. The inoculated products were sampled for microbial survivors at days 7, 14, and 28 following initial inoculation at room temperature. The number of surviving organisms were calculated as a Log10 reduction from the original inocula. 2. In-use test: a total of 100 bottles were collected after instillation of preservative-free fluoroquinolone eyedrops in volunteer patients after 1 week of use. The remaining fluid and tips of the bottles were cultured. Colonies on the plates were counted at the end of the incubation period. All microorganisms were identified by Gram staining and biochemical assays. 1. Challenge test: preservative-free gatifloxacin and levofloxacin demonstrated a lower log reduction against A. niger than preserved fluoroquinolones and preservative-free moxifloxacin at all time points. 2. In-use test: There was no contamination identified on plates inoculated by preservative-free quinolone bottles after 1 week of use in this study. Physicians should be aware of the lower antifungal preservative effectiveness of some preservative-free fluoroquinolone preparations than preserved ones.

Comparative efficacy evaluation of disinfectants routinely used in hospital practice: India

Aim:The aim of this study was to evaluate and compare practically achieved disinfection efficacy of some locally available disinfectants on surfaces and infectious microbiological hospital waste.Materials and Methods:Seven disinfectants were tested at concentrations recommended by manufacturers on rough and smooth surfaces that were contaminated experimentally by locally circulating isolates of methicillin-resistant Staphylococcus aureus, multidrug-resistant Acinetobacter baumannii, Klebsiella pneumoniae, Enterobacter aerogenes, Pseudomonas aeruginosa strains, standard isolate of Salmonella typhi and Candida albicans. Reduction in microbial counts before and after surface disinfection was expressed as log reduction. A very heavy microbial waste load was simulated by immersing culture plates with heavy microbial growth in disinfectants. Daily, a sample of disinfectant was taken and subjected to in-use test.Results:The highest average log reduction of test microbes on the rough surface was given by DesNet (5.05) and Bacillocid special (5.02). A comparable average log reduction of test microbes on a smooth steel surface was noted (5.68, 5.67, 5.50) for Lysol, Bacillocid sp. and DesNet, respectively. In the discard jars, Bacillocid special worked satisfactorily for 4 days, DesNet for 3 days and Hi-giene Germitol for 1 day. The remainder of the disinfectants failed in the in-use test on Day 1. Phenolics, although widely used in our settings, may not be as good surface disinfectants as newer formulations like DesNet and Bacillocid special.Conclusions:Newer quaternary ammonium compounds and aldehyde formulations were found to be the best disinfectants for disinfection of heavy contamination.

동물용의약품의 환경 중 위해성 평가를 위한 토양 잔류성 시험법 가이드라인

최근, 동물 및 인체용 의약품류는 환경 중 새로운 오염물질로 부각되고 있다. 특히, 우리나라는 동물용의약품에 대한 수의사 처방제 미정착, 집약적 축산환경, 최근의 대규모 지속적 동물 전염병의 발생, 단위 육류 생산량 증대를 위한 동물용의 약품의 남용, 축산분뇨의 해양투기 전면 금지 등 축산분야의 위협적 요소와 함께 환경 중 동물용의약품의 잔류성 문제가 향후 식품오염 및 항생제 내성 유발 등의 요인으로 확대 될 우려가 크다. 그러므로 동물용의약품의 주된 환경배출 매개인 분변을 통한 토양 잔류성 검토는 지하수 오염과 지하수 또는 분변 중 잔류량의 흡수, 이행과정을 통한 농경지 작물의 오염 예방을 위해서도 동물용의약품의 인허가 단계 중 토양 잔류성을 환경 위해성 평가자료로 검토하는 것은 중요한 의의를 갖는다. 본 연구는 VICH, OECD 등의 국제적 기구에서 그 동안 제안하였거나, 검토 중인 동물용의약품의 환경위해성 평가 가이드 라인과 오랫동안 우리나라, 미국, 유럽 등지에서 정착되어 온 농약의 토양 중 잔류성 시험법, 그리고 문헌을 토대로 기 수행한 동물용의약품의 토양잔류성 시험 결과를 바탕으로 하여 동물용의약품의 환경 중 위해성 평가를 위한 토양 잔류성 시험법 가이드라인을 제안하였다. 시험법 가이드라인은 크게 실내, 실외 시험 방법과 잔류소실기의 예측으로 구성되어 있으며, 농경지토양 내 분변을 통한 노출 경로를 주안으로 하여 우리나라 환경에 적합토록 구성하였다. BACKGROUND: To assess and prevent the environmental impacts and risks by veterinary pharmaceuticals, Guidance on Estimating Soil Persistence and Degradation Kinetics from Environmental Fate Studies on Veterinary Pharmaceuticals for Environmental Risk Assessment was proposed. METHODS AND RESULTS: Proposed guidance was coined by VICH, EU guideline, OECD guideline and soil dissipation studies for the purpose of international harmonizing. Guidance was also modified from pesticide soil persistence testing guidelines of US, EU, and Korea, with practical approaches adopting in-use test guideline for Korea. CONCLUSION(S): Proposed guidance are consisted of three parts; Laboratory Soil Experiment, Field Soil Dissipation Study, and Estimation of <TEX>$DT_{50}/DT_{90}$</TEX>. Proposed guidance is to be available for the requirement for registration of veterinary pharmaceuticals with fit for purpose in Korea.

Comparison of Three Skin Disinfectant Solutions used for Skin Preparation prior to Spinal and Epidural Anaesthetic Procedures in Parturients at De Soyza Maternity Hospital and Castle Street Hospital for Women

Background Effective skin disinfection before spinal and epidural anaesthesia is essential to avoid bacterial infection. Three disinfectants, Betadine, Cetavlon and a combination of Chlorhexidine, Cetrimide and Isopropyl alcohol are used in hospitals as skin disinfectant solutions. We compared the ability of these disinfectant solutions to reduce the bacterial skin flora prior to anaesthetic procedures. Method 80 Pregnant women admitted to Castle Street Hospital for Women (CSHW) and De Soysa Maternity Hospital (DMH) who received epidural or spinal anaesthesia were studied. They were randomly assigned to receive skin preparation with Betadine, Cetavlon and the combined preparation. Two cultures were obtained from each subject; just prior to skin disinfection and immediately following disinfection. In-use test was performed to determine bacterial contamination of newly opened and multiple used bottles from each group. Results The reduction in bacterial colony forming units (CFU) following application of disinfectant in all three groups were significant (p Conclusion The combined preparation consisting of Chlorhexidine, Cetrimide and Iso propyl alcohol showed the best reduction of skin flora followed by Cetavlon and Betadine. Key words: disinfectants, bacterial flora doi: 10.4038/slja.v17i1.408 Sri Lankan Journal of Anaesthesiology 17(1) : 5 - 10 (2009)

Eye irritation of low-irritant cosmetic formulations: correlation of in vitro results with clinical data and product composition

Alternative methods to the Draize eye irritation test, such as the hen’s egg test-chorioallantoic membrane (HET-CAM) or the bovine corneal opacity and permeability (BCOP) tests, are currently used to evaluate the irritant potential of cosmetic or consumer products. Although, for strong irritants, the results of these tests correlate well with those of the Draize test, they appear to be less suited to identify mild irritants. In order to improve the sensitivity of alternative eye irritation tests, we developed a novel method that uses a human corneal epithelial cell line (CEPI), and the endpoints of cytotoxicity and IL-8 release. Twelve make-up removers were assessed by the HET-CAM, BCOP and CEPI tests, as well as in a clinical in-use test under ophthalmological control after their application to the external eye lid. In addition, we investigated the impact of osmolality and raw material composition on in vitro and clinical results and compared the in vitro results with those of clinical studies. Overall, although HET-CAM results were unrelated to eye discomfort and adverse clinical signs, they correlated mainly with the presence and concentration of surfactants in the test articles. BCOP scores were unrelated to clinical signs, but related mainly to glycol and sodium lactate content and concentration in the test articles. Cytotoxicity in CEPI mainly correlated with presence and concentrations of surfactants, and IL-8 release to clinical signs and/or glycol and sodium lactate concentrations. Overall, IL-8 release appeared to be the most sensitive and reliable endpoint to predict human eye tolerance to mildly irritant products. Although our results suggest that the IL-8 assay appears to be a promising screen for borderline-irritant formulations, further experiments are required to confirm and validate these preliminary results.

Ozone Sterilization: Another Option for Healthcare in the 21st Century

BACKGROUND: Ozone has been recognized as a safe disinfectant for water and food for many years now. It can be safely used in both gaseous and aqueous forms as an antimicrobial agent in the treatment, storage, and processing of foods, including meat and poultry. The company, TSO3. Inc., has developed a unique sterilization process for heat-sensitive materials using ozone as the sterilizing agent. The microbial efficacy of the TSO3 125L Sterilizer was established by demonstrating that the process could achieve a Sterility Assurance Level of 10–6 (SAL-6). METHODS: An overkill approach was used for the demonstration of SAL-6 for viruses, fungi, vegetative bacteria, mycobacteria, and bacterial spores. Paper-strip carriers were inoculated with 106 colony-forming unit (CFU) of the studied microorganisms only, or by a mixture of hard water (400 ppm) or serum (10%). Contaminated carriers were distributed in a validation load and exposed to partial cycle in the TSO3 125L sterilizer. D-values were calculated using the limited Holcomb-Spearman-Karber methods. Inoculated medical devices and narrow lumens were also tested as actual medical devices in hospital loads (in-use test). RESULTS: Resistance of the microorganisms tested to the process is, from less to more resistant, vegetative bacteria < fungi < mycobacteria < bacterial spores. Among the spore-forming bacteria, spores of Geobacillus stearothermophilus are the most resistant. Simulated-use testing demonstrates the efficacy of the process to sterilize lumens devices, hinges, and other instrument challenges. In-use testing confirms these results. CONCLUSION: In September 2003, the company obtained its United States 510K clearance to market. As infection control professionals continue to search for ways to lower the number of nosocomial infections in hospital, this technology can present some significant benefits for the sterilization low-temperature medical devices.

In-use evaluation of Perasafe ® compared with Cidex ® in fibreoptic bronchoscope disinfection

The mycobactericidal activity of Perasafe ® (0.26% peracetic acid) was compared with that of Cidex ® (2% alkaline glutaraldehyde) by an in-use test. Fibreoptic bronchoscopes were artificially contaminated with Mycobacterium tuberculosis or Mycobacterium avium–intracellulare in sputum and, after manual pre-cleaning with a neutral soap, 10 and 20 min disinfection periods were tested. Perasafe ® was as effective as Cidex ®, thus requiring a 10 min disinfection period against M. tuberculosis and 20 min against M. avium–intracellulare. The results demonstrate that Perasafe ® is an effective disinfectant for use in reprocessing fibreoptic bronchoscopes.

Methods to Evaluate Cleaners and Sanitizers

Methods to evaluate germicides can be grouped into three categories: standard laboratory tests, in-use tests and simulated-use tests. Standard laboratory methods, such as the Available Chlorine Germicidal Equivalent test, are specifically defined for reproducibility in any laboratory by any operator, but the test results often lack relevance to actual product-use conditions. In-use test methods are relevant to product-use; however, in-use test procedures do not permit proper controls to be included in the organism recovery methods. Contact plates give an estimate of organism numbers which is only 25% of the theoretical number of organisms present. Organism recovery using a swab, cellulose sponge or tube sampler give estimates of organisms ranging from 91 to 111% of theoretical. The tube sampler is a 1-in. length of flexible tubing having a 1-in. interior diameter and a smooth end, which can make a water-tight seal on a flat surface. Simulated use testing yields data which are relevant to actual product-use. A cafeteria tray is soiled, inoculated and cleaned in a manner to simulate actual product-use. This test method permits the necessary controls to be used. Tray-test reproducibility is as good as that of the other recovery methods tested and organism recovery is quantitative. The tray test provides a means for determining biological cleaning where the effect of both cleaning and germicidal activity are measured together.

Experimental design and statistical analysis of an in-use test of germicidal detergents

Present methodology for the in-use testing of germicidal detergents is too time-consuming for routine use by a hospital environmentalist. A simplified experimental design and statistical analysis, amenable to routine use, is presented for the in-use testing of germicidal detergents against water alone. As an illustration of our methodology we evaluated two germicidal detergents versus water alone. Under our conditions of use, it was found that water alone was equally and significantly as effective (p less than 0.001) as the two germicidal detergents in reducing microbial contamination of floors.

Stabilized compressed nitroglycerin tablets.

A stabilized compressed nitroglycerin tablet, containing microocrystalline cellulose NF and providone NF as stabilizing agents, was formulated. Bioavailability and physical tests were conducted on the compressed tablet and two leading brands of molded tablets. There was no difference in the mean pulse rate between a molded tablet formulation and the compressed tablet in a crossover study using 10 human volunteers and three tablet strengths, 0.3, 0.4, and 0.6 mg. The compressed tablet was most uniform when tested according to the USP method for weight variation and content uniformity. Various tests for nitroglycerin loss due to volatility, i.e., open dish test, thermogravimetric analysis, and simulated in-use test, all indicated that the stabilized compressed tablet was substantially more stable than partially stabilized or unstabilized molded tablets.