[Repurposing of betablockers in dermatology]

Betablockers are used for decades in the treatment of cardiovascular diseases. Recently, the repurposing of the wide spectrum betablocker propranolol revolutionized the infantile hemangioma management. Besides, betablockers have been shown to significantly improve the prognosis of melanoma patients. Blocking the adrenergic receptors blocks the stress-induced tumorigenic pathways. Propranolol inhibits melanoma by downregulating the tumor angiogenesis but also tumor cell proliferation, invasiveness and local immune suppression. These antitumor effects have been observed in other cancers. The repurposing of propranolol has already changed the practice of pediatricians and dermatologists and may soon help oncologists treat various cancers.

Remobilization Dynamics of Caffeine, Ciprofloxacin, and Propranolol following Evaporation-Induced Immobilization in Porous Media

Changing weather conditions can cause cycles of wetting and drying in the unsaturated zone. When porewater evaporates, any nonvolatile solutes present in the pores will be driven to adsorb and ultimately precipitate on solid surfaces. When media are subsequently resaturated through rainfall infiltration, the remobilization of solutes likely depends on both the hydraulics of resaturation and the dynamics of dissolution processes. The focus of this work was to study the dynamics of remobilization of three different emerging contaminants (caffeine, ciprofloxacin, and propranolol) and two model compounds (fluorescein and sulforhodamine B) from porous media following evaporation of porewater. Remobilization column experiments were conducted to study this phenomenon and were evaluated using a finite difference model developed to simulate the adsorption-desorption dynamics during resaturation and elution. Results indicate that dissolution dynamics become increasingly important with increasing adsorption affinity for solid surfaces. Trends in observed elution behavior are not well-predicted from chemical properties, such as solubility. One of the most significant observations of the work is the presence of spikes in elution concentrations well above initial porewater concentration, resulting from the hydraulics of the resaturation process. The effect is most significant in highly mobile compounds that exhibit low adsorption affinity for solid surfaces.

[Chinese expert consensus on the use of topical timolol maleate treatment of infantile hemangiomas]

Non-selective β-blocker propranolol has been proved by FDA as the first-line agent for infantile hemangioma (IH) with dramatic response. To reduce the side effects caused by systemic administration of propranolol, timolol maleate treatment has been increasingly used as an alternative to systemic β-blockers and watchful waiting for many IH patients in recent years. However, the appropriate indications, drug dosage, dosing regimen, time for initiation, optimal duration, monitoring for side effects still remains controversial. To standardize the use of topical timolol in treating IH, avoid overtreatment or under-treatment, as well as minimize complications, a Chinese expert consensus on the use of topical timolol treatment of IH has been approved and written by a multidisciplinary experts group based on an up-to-date literature review and repeated discussion, which can be used to reduce inappropriate variations in clinical practice and to promote the delivery of high quality, evidence-based health care for IH patients.

[Effects 'of β3 adrenoceptors on the contractility of rat thoracic aorta smooth muscle and the mechanism]

OBJECTIVE

To observe the effect of β₃adrenoceptors (β₃-AR) activation on rat thoracic aorta smooth muscle contractility and the possible related mechanism.

METHODS

The endothelium removed thoracic aorta was pre-contracted with 30 mmol/L KCl physiological saline solution (PSS). Then the tension of the thoracic aorta was recorded in presence of BRL37344 (BRL) to determine the action of β₃-AR. The tension of the thoracic aorta was also recorded in the presence of Propranolol (PRA), SR59230A (SR), L-NNA, H-89 and Iberiotoxin (IBTX) respectively to reveal the underling mechanism of β₃-AR activation on rat vascular smooth muscle. Immunohistochemistry was adopted to confirm the existence and the distribution of β₃-AR in rat thoracic aorta.

RESULTS

The results showed that: (1) The thoracic aorta was relaxed by β₃-AR activation, with a relaxation percentage of (10.59 ± 0.79). (2) β₃-AR was expressed in both endothelial and smooth muscle layer in thoracic aorta sections of rats. (3) PRA did not block the effect of BRL on the thoracic aorta. The relaxation actions of BRL could be antagonized by pre-incubating the thoracic aorta with SR. (4) L-NNA (a NOS inhibitor) and H-89 (a PKA inhibitor) reversed the relaxation effect of BRL on vascular smooth muscle. (5) The effect of BRL was decreased after application of Ibriotoxin (IBTX), a large conductance calcium dependent potassium channel blocker.

CONCLUSION

The results confirmed that activation of β₃-AR led to relaxation of thoracic aorta smooth muscle. The relaxation action of β₃-AR on smooth muscle of rat thoracic aorta was related to activation of NOS and PKA signaling pathway. Large conductance Ca²⁺-K⁺ channels were involved in the relaxation action of β₃-AR activation on rat thoracic aorta smooth muscle.

[Diagnostic value of the propranolol-exercise provocative test for growth hormone deficiency in children]

OBJECTIVE

To assess the diagnostic value of the propranolol-exercise provocative test for growth hormone deficiency (GHD) in children.

METHODS

This study included 120 children who received both the insulin provocative test and the propranolol-exercise provocative test due to short stature between January 2009 and March 2013. Growth hormone (GH) levels in venous blood were measured before and after the provocative test. Peak GH <10 ng/mL was defined as negative stimulation, while peak GH ≥10 ng/mL was defined as positive stimulation. The children whose peak GH levels were <10 ng/ mL after both tests were diagnosed with GHD.

RESULTS

Twenty-nine (24.2%) of the 120 children with short stature were diagnosed with GHD. The positive rate in the insulin provocative test was 48.3%, versus 65.8% in the propranolol-exercise provocative test. The overall coincidence rate and positive coincidence rate of the two tests were 62.5% and 79.3%, respectively. The peak GH after the propranolol-exercise provocative test was significantly higher than that after the insulin provocative test (P<0.01). Peak GH occurred mostly at 30-60 minutes after the insulin provocative test, while that occurred mostly at 120 minutes after the propranolol-exercise provocative test. No adverse effects were observed in the propranolol-exercise provocative test.

CONCLUSIONS

Coincidence rates in stimulating the secretion of GH are high between the propranolol-exercise provocative test and the insulin provocative test. Compared with the insulin provocative test, the propranolol-exercise provocative test is more likely to stimulate the secretion of GH. GHD can be clinically diagnosed by the insulin provocative test combined with the propranolol-exercise provocative test.

[Expression of serum and urinary vascular endothelial growth factor-A and epidermal growth factor-like domain 7 in proliferating hemangioma treated with propranolol]

OBJECTIVE

This study aims to investigate the expression levels of serum and urinary vascular endothelial growth factor-A (VEGF-A) and epidermal growth factor-like domain 7 (EGFL7) in proliferating infantile hemangioma patients under propranolol treatment.

METHODS

Propranolol (0.5-2 mg x kg(-1)) was orally administered to 30 infants every day for 4-8 months. The Achauer method was used to measure the tumor radius and thus evaluate the clinical curative effects of the treatment. Enzyme-linked immunosorbent assay was used to measure the serum and urinary concentrations of VEGF-A and EGFL7 at 0, 4, and 12 weeks after the treatment.

RESULTS

The treatment response was excellent in 2 patients, good in 11, moderate in 14, and poor in 3. Serum VEGF-A (335.692 pg x mL(-1) ± 136.146 pg x mL(-1)) was high before the treatment and then significantly decreased after 4 weeks (264.853 pg x mL(-1) ± 122.120 pg x mL(-1)) and 12 weeks (211.345 pg x mL(-1) ± 104.035 pg x mL(-1)) of treatment (P < 0.05). Urinary VEGF-A (76.234 pg x mL(-1) ± 24.169 pg x mL(-1)) was high before the treatment and then significantly decreased after four weeks (56.454 pg x mL(-1) ± l6.111 pg x mL(-1)) and twelve weeks (34.728 pg x mL(-1)) ± 12.656 pg x mL(-1)) of treatment (P < 0.05). Serum and urinary EGFL7 also decreased after the treatment, showing a positive relationship with VEGF-A.

CONCLUSION

Propranolol can be safely and effectively used to treat proliferating infantile hemangiomas. This treatment can reduce the peripheral serum and urinary concentrations of VEGF-A and EGFL7 in affected children.

Beta-blockers in the environment: part II. Ecotoxicity study

The increasing consumption of beta-blockers (BB) has caused their presence in the environment to become more noticeable. Even though BB are safe for human and veterinary usage, ecosystems may be exposed to these substances. In this study, three selected BB: propranolol, metoprolol and nadolol were subjected to ecotoxicity study. Ecotoxicity evaluation was based on a flexible ecotoxicological test battery including organisms, representing different trophic levels and complexity: marine bacteria (Vibrio fischeri), soil/sediment bacteria (Arthrobacter globiformis), green algae (Scenedesmus vacuolatus) and duckweed (Lemna minor). All the ecotoxicological studies were supported by instrumental analysis to measure deviation between nominal and real test concentrations. Based on toxicological data from the green algae test (S. vacuolatus) propranolol and metoprolol can be considered to be harmful to aquatic organisms. However, sorption explicitly inhibits the hazardous effects of BB, therefore the risks posed by these compounds for the environment are of minor importance.

[Clinical analysis for treatment of 1 080 cases of infantile hemangiomas with oral propranolol]

OBJECTIVE

To explore the indications of hemangiomas of different types by observing the clinical efficacy of oral propranolol.

METHODS

For this retrospective study from October 2009 to June 2013, a total of 1 080 cases were classified into 5 types according to their clinical characteristics. There were 338 males and 742 females. Their types were telangiectasis (n = 58), papular (n = 424), plump (n = 106), deep (n = 176) and mixed (n = 306). Propranolol was orally administered at a dose of 1.0 or 1.5 mg/kg daily (1.0 mg/kg for infants aged 2.5 months or under; 1.5 mg/kg for those aged 2.5 months or above). Dynamic observations of hemangioma size, texture or color change and adverse events during treatment were performed. Drug withdrawal was usually made after dosing for 1 year or under when there was a total regression of hemandiomas. The efficacy was evaluated on a 4-level scale.

RESULTS

Rank test results showed no significant differences between 5 types during the changes of lesions (χ² = 1.738, P > 0.05). Changing of lesions occurred 8.0 (3.7, 16.2) hours after dosing in telangiectasis type, whereas 6.5 (4.1, 14.3) hours in papular type, 7.0 (5.5, 12.7) hours in plump type, 7.5 (3.8, 11.3) hours in deep type and 6.5 (4.2, 13.4) hours in mixed type. After a follow-up of 6 months to 2.5 years, there were 378 grade IV case (35.00%), 574 grade III case (53.15%), 120 grade II cases (11.11%) and 8 grade I cases (0.74%). And there were significant differences between patients of different types (P < 0.05). Patients of deep type had the best grade IV curative effect rate of 59.09% (104/176) , then papular type of 51.25% (162/316) and telangiectasis type of 26.41% (112/424).

CONCLUSION

As a first-line treatment for hemangioma, propranolol shows excellent efficacies for patients of deep, mixed, plaque and papular types.

Topical application of a new monoclonal antibody against fibroblast growth factor 10 (FGF 10) mitigates propranolol-induced psoriasis-like lesions in guinea pigs

OBJECTIVES

Psoriasis is a chronic inflammatory skin disease characterized by excessive proliferation of keratinocytes. Fibroblast growth factor 10 (FGF10) acts as a growth factor for keratinocyte proliferation. The aim of this study is to investigate whether FGF10 blockage, a new monoclonal antibody against FGF10 we generated, could mitigate topical propranolol-induced psoriasis-like lesions in guinea pigs.

MATERIALS AND METHODS

The monoclonal anti-FGF10 was generated by a routine method and purified by affinity chromatography. The effect of FGF10 and anti-FGF10 on human keratinocyte HaCaT cell proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The back of the ears of individual guinea pigs was topically exposed to 5% propranolol emulsion to induce psoriasis-like lesions and randomly treated topically with phosphate buffered saline (PBS), hydrocortisone butyrate, or different doses of anti-FGF10. The pathologic changes and the degrees of inflammation in the auricular areas of individual animals were examined histologically.

RESULTS

Characterization revealed that anti-FGF10 had a purity of 90% and a titer of 1:12800. We found that FGF10 stimulated HaCaT cell proliferation while treatment with different doses of anti-FGF10 inhibited FGF10-induced cell proliferation in a dose-dependent manner (100, 200 ng/ml, p < 0.05 vs. control; 400, 800, 1600 ng/ml, p < 0.01 vs. control). Compared to PBS-treated psoriatic animals, treatment with anti-FGF10, like hydrocortisone butyrate, greatly inhibited the severity of psoriasis-like lesions by reducing the Baker's scores, the thickness of epidermis, and the numbers of monocyte infiltrates in the dermis of animals.

CONCLUSIONS

The newly generated anti-FGF10 monoclonal antibody inhibited the proliferation of human keratinocytes in vitro and mitigated inflammation and pathogenic changes in propranolol-induced psoriasis-like lesions in animals. Therefore, these findings may provide a proof of principle that blockage of FGF-10 may inhibit psoriasis-related inflammation.

Pediatric oral solutions with propranolol hydrochloride for extemporaneous compounding: the formulation and stability study

The aim of this study is to formulate an extemporaneous pediatric oral solution of propranolol hydrochloride (PRO) 2 mg/ml for the therapy of infantile haemangioma or hypertension in a target age group of 1 month to school children and to evaluate its stability. A citric acid solution and/or a citrate-phosphate buffer solution, respectively, were used as the vehicles to achieve pH value of about 3, optimal for the stability of PRO. In order to mask the bitter taste of PRO, simple syrup was used as the sweetener. All solutions were stored in tightly closed brown glass bottles at 5 ± 3 °C and/or 25 ± 3 °C, respectively. The validated HPLC method was used to evaluate the concentration of PRO and a preservative, sodium benzoate, at time intervals of 0-180 days. All preparations were stable at both storage temperatures with pH values in the range of 2.8-3.2. According to pharmacopoeial requirements, the efficacy of sodium benzoate 0.05 % w/v was proved (Ph.Eur., 5.1.3). The preparation formulated with the citrate-phosphate buffer, in our experience, had better palatability than that formulated with the citric acid solution.

KEYWORDS

propranolol hydrochloride pediatric preparation extemporaneous preparation solution stability testing HPLC.

Thermal sintering: a novel technique in the design of gastroretentive floating tablets of propranolol HCl and its evaluation

The aim of the present investigation was to formulate thermally sintered floating tablets of propranolol HCl, and to study the effect of sintering conditions on drug release, as well as their in vitro buoyancy properties. A hydrophilic polymer, polyethylene oxide, was selected as a sintered polymer to retard the drug release. The formulations were prepared by a direct compression method and were evaluated by in vitro dissolution studies. The results showed that sintering temperature and time of exposure greatly influenced the buoyancy, as well as the dissolution properties. As the sintering temperature and time of exposure increased, floating lag time was found to be decreased, total floating time was increased and drug release was retarded. An optimized sintered formulation (sintering temperature 50 degrees C and time of exposure 4 h) was selected, based on their drug retarding properties. The optimized formulation was characterized with FTIR and DSC studies and no interaction was found between the drug and the polymer used.

Primary headaches associated with sexual activity respond to topiramate therapy: a case report

Primary headaches are rarely associated with orgasms. Indomethacin at doses of 25-50 mg/day taken 30-60 minutes prior to sexual activity may prevent headaches. Propranolol and metoprolole have been used for headaches that consistently emerge during frequent sexual activity of any type. It is also known that topiramate is useful for treating migraines, but it is rarely used for other primary headaches. The role of topiramate in the treatment of headaches associated with sexual activity is unclear. Indomethacin and propranolol could not be used in our patient who, besides sexual activity-associated headaches, suffered from gastritis and diabetes mellitus. Thus, topiramate (50 mg/day) was used prophylactically, and sexual activity-associated headaches did not recur during 6 months of topiramate therapy. This is the first report of positive response to topiramate as prophylactic treatment against sexual activity-associated headaches when propranolol and indomethacin are contraindicated.

Own experience in the treatment of infantile haemangiomas with propranolol - preliminary results

BACKGROUND

Infantile haemangiomas are the most common vascular tumours in children. Since 2008 the application of propranolol has been a promising therapy in the management of haemangiomas.

AIM OF THE STUDY

Analysis of the patients with infantile haemangiomas treated with propranolol.

MATERIAL AND METHODS

Between June 2009 and December 2010 in Department of Pediatric Surgery and Oncology Medical University of Lodz, 35 children with infantile haemangiomas (29 females and 6 males) were treated with propranolol. Therapy was initiated in age of 2-15 months (mean 4.5). All infantile haemangiomas were in a proliferative phase. In 27 children lesions were located in the head and neck, 2 of them were located in the orbital region and 3 penetrated into the orbit. In 5 children haemangiomas were located in the trunk, with 3 in the perineum and 3 in limbs. In 2 children the PHACE Syndrome was diagnosed. In one of these cases exploratory laparatomy revealed jejunal haemangiomatosis. The indication for propranolol application was impairment of physiological functions in 23 cases, cosmetic defect in 8 and ulceration in 4. The duration of treatment was 4 to 12 months (mean 7.5-months). The change of haemangioma volume, density and colour were evaluated. Reduction of ˝ haemangioma volume was assessed as very good response, 1/3 as good response, and 1/4 as poor.

RESULTS

In 7 patients therapy has been finished. In all cases decrease in density, volume and fading was observed. Very good result was achieved in 27 patients, good in 5, poor in 3. Recurrence of haemangioma appeared in two patients after termination of treatment. A spectacularly good result was achieved in the child with PHACE syndrome and in one with jejunal haemangiomatosis.

CONCLUSIONS

Propranolol therapy is safe and effective in children with infantile proliferating haemangiomas. It can be the treatment of choice in cases with impairment of physiological functions or severe cosmetic defect. Election and therapy of the children should be carried out in highly reference centres.

Intestinal permeability of sesquiterpenes in the caco-2 cell monolayer model

The intestinal permeability of eight sesquiterpenes which are active constituents of some traditional Chinese medicines, were studied by using the Caco-2 cell monolayer; they include tanacetin, artesin, magnolialide, crossostephin, atractylon, isocalamenediol (ICL), bisabolangelone (BSE) and (3 R)-des- O-methyllasiodiplodin (DML). The bidirectional permeability of the eight sesquiterpenes was studied from the apical (AP) side to the basolateral (BL) side or from the BL side to the AP side. The eight compounds were assayed by HPLC. Transport parameters and apparent permeability coefficients ( P(app)) were then calculated. The bidirectional P(app) values of the eight compounds were compared with those of propranolol, a marker of high permeability and transcellular transport. The transport of the eight sesquiterpenes was concentration-dependent in the range of 10-200 microM. Lower recoveries of ICL, BSE and DML than other sesquiterpenes were found during transport. The results indicated that all the sesquiterpenes are well absorbed mainly by the passive diffusion via the transcellular pathway and metabolism may be involved during the absorption of ICL, BSE and DML.

Associated conduction disturbances in patients with symptomatic sinus node disease

Electrophysiological investigations were performed in 30 patients with symptomatic sinus node disease (SND) to assess the extent and distribution of associated functional disturbances in the conduction system. The tests were performed before and after inhibition of autonomous tone with propranolol, 0.1 mg/kg, and atropine, 0.02 mg/kg. Surface ECG had shown bundle branch blocks (BBB) in 5 patients and fascicular blocks in 2. AV block I had been recorded in 4 patients, while none had shown high-degree AV block. Malfunction was most often detected in the AV junction, 17 patients showing a prolonged conduction time or an abnormal effective AV node refractory period. Intraventricular conduction delay was present in 7 patients, with a prolonged HV interval in 3 and a complete permanent BBB in the others. Rate-dependent BBBs were demonstrated in a further 4 patients. Long cardiac arrests following interruption of atrial pacing, suggesting impaired automaticity also of subsidiary escape pacemakers, were seen in 11 patients. Only 6 patients, 20%, showed no signs of associated malfunction of the conduction system. Thus, detailed electrophysiological assessment demonstrated associated conduction abnormalities in the majority of these SND patients. The results agree with histopathological studies and show that sinus node malfunction is often the clinically apparent manifestation of a widespread degenerative process in the cardiac conduction system.

Analytical characterization of chiral drug-protein interactions: comparison between the optical biosensor (surface plasmon resonance) assay and the HPLC perturbation method

Two modern, fundamentally different methods were used for a detailed investigation of enantioselective drug-protein interactions, a surface plasmon resonance (SPR)-based Biacore 2000 biosensor assay and the previously validated HPLC perturbation method (HPLC-PM). This is the first time SPR has been used for this purpose. The fundamental features of the two methods were investigated, and the consequences for operation and data evaluation were addressed. With HPLC-PM, chiral data could be obtained directly from the racemic mixture, whereas a separate analysis of each pure enantiomer was required to obtain chiral data with SPR. It was shown that if chirality is not attributed in the SPR analysis, misleading average racemic binding constants will be obtained. Both drug and protein consumption were considerably higher with HPLC-PM. HPLC-PM was found to be best suited for measurements of weak affinity interactions, whereas the SPR method was best for strong interactions. With both methods, the presence of DMSO in the samples severely affected the interactions, introducing errors. The binding of the beta-blockers alprenolol and propranolol to Cel7a cellulase was used as a model system. These methods gave results that agreed quite well qualitatively, but considerable quantitative deviations were sometimes obtained.

The effect of thyme extract on beta2-receptors and mucociliary clearance

Thyme is a broncholytic und secretomotoric agent. Thus, our aim was to investigate the influence of a thyme extract on beta (2)-receptors in competition binding experiments and relaxation experiments on rat uteri and trachea. Furthermore, the influence of the extract on respiratory clearance was of interest. Binding experiments were performed using purified rat lung membranes with the beta(2)-receptor ligand [(125)I]-CYP {[(125)I]-(+/-)-Iodocyanopindolol}. The transport of the fluorescence dye rhodamin 123 concerning ciliary action in the tracheal area of a mouse was investigated using a microdialysis technique. The thyme extract reduces only slightly [(125)I]-CYP binding and amplifies the displacement of [(125)I]-CYP by propranolol (non-specific beta-receptor antagonist): the displacement curve in the concentration range representing beta (2)-receptors (nM) is shifted to the left. Thyme extract had relaxing effects on organs possessing beta (2)-receptors (uterus and trachea). The propranolol-induced antagonism to isoprenaline is reverted concentration-dependently by the extract. A duplication of the rate of ciliary clearance by the extract was observed.

IN CONCLUSION

1) There is evidence for an influence of a thyme extract on beta (2)-receptors by both binding studies and biological effects: As can be derived from the shift of the propranolol displacement curve (nM), ingredients of the thyme extract slightly interact with beta (2)-receptors in rat lung tissue. This effect is indirect since no full range competition curve was reached. 2) An at least indirect interaction with beta (2)-receptors in rat uteri and trachea is revealed by a decreased antagonism of propranolol on the relaxing effect of isoprenaline by the plant extract. 3) An additional mechanism is presumed because at high extract concentrations isoprenaline-induced relaxation is complete, whereas the displacement of propranolol at beta (2)-receptors is only weak. 4) Thyme extract has an indirect (modulatory) effect on the beta (2)-receptor system. 5) Mucociliary clearance is improved in vivo. Its mechanism has still to be elucidated.

A comparison of ionic liquids to molecular organic solvents as additives for chiral separations in micellar electrokinetic chromatography

In this study, we report the effects of adding ionic liquids (ILs), as compared to adding conventional molecular organic solvents (MOSs), to aqueous buffer solutions containing molecular micelles in the separation of chiral analyte mixtures in micellar EKC (MEKC). The molecular micelle used in this study was polysodium oleyl-L-leucylvalinate (poly-L-SOLV). The ILs were 1-alkyl-3-methylimidazolium tetrafluoroborate, where the alkyl group was ethyl, butyl, hexyl, or octyl. These ILs were chosen due to their hydrophobicity, good solvating, and electrolyte properties. Thus, it was expected that these ILs would have favorable interactions with chiral analytes and not adversely affect the background current. Common CE buffers, mixed with a molecular micelle, and an IL or a MOS, were used for these chiral separations. The buffers containing an IL in the concentration range of 0.02-0.1 v/v were found to support a reasonable current when an electric field strength of 500 V/cm was applied across the capillary. However, a current break down was observed for the buffers containing more than 60% v/v MOS on application of the above-mentioned electric field. The chiral resolution and selectivity of the analytes were dependent on the concentration and type of IL or MOS used.

Uniform molecularly imprinted microspheres and nanoparticles prepared by precipitation polymerization: the control of particle size suitable for different analytical applications

Molecularly imprinted polymers (MIPs) are being increasingly used as selective adsorbents in different analytical applications. To satisfy the different application purposes, MIPs with well controlled physical forms in different size ranges are highly desirable. For examples, MIP nanoparticles are very suitable to be used to develop binding assays and for microfluidic separations, whereas MIP beads with diameter of 1.5-3 microm can be more appropriate to use in new analytical liquid chromatography systems. Previous studies have demonstrated that imprinted microspheres and nanoparticles can be synthesized using a simple precipitation polymerization method. Despite that the synthetic method is straightforward, the final particle size obtained has been difficult to adjust for a given template. In this work, we initiated to study new synthetic conditions to obtain MIP beads with controllable size in the nano- to micro-meter range, using racemic propranolol as a model template. Varying the composition of the cross-linking monomer allowed the particle size of the MIP beads to be altered in the range of 130 nm to 2.4 microm, whereas the favorable binding property of the imprinted beads remained intact. The chiral recognition sites were further characterized with equilibrium binding analysis using tritium-labeled (S)-propranolol as a tracer. In general, the imprinted sites displayed a high chiral selectivity: the apparent affinity of the (S)-imprinted sites for (S)-propranolol was 20 times that of for (R)-propranolol. Compared to previously reported irregular particles, the chiral selectivity of competitive radioligand binding assays developed from the present imprinted beads has been increased by six to seven folds in an optimized aqueous solvent.